Veröffentlichungen

Veröffentlichungen von Autoren des Instituts für Informatik

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2022[ to top ]

Wolf, E., Döllinger, N., Mal, D., Wenninger, S., Bartl, A., Botsch, M., Latoschik, M.E., Wienrich, C.: Does Distance Matter? Embodiment and Perception of Personalized Avatars in Relation to the Self-Observation Distance in Virtual Reality. Frontiers in Virtual Reality. (2022).
- [ Abstract ]
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Virtual reality applications employing avatar embodiment typically use virtual mirrors to allow users to perceive their digital selves not only from a first-person perspective but also from a holistic third-person view. However, due to distance-related biases such as the distance compression effect or a reduced relative rendering resolution, the self-observation distance (SOD) between the user and the virtual mirror might influence how users perceive their embodied avatar. Our article systematically investigates the effects of a short (1 meter), middle (2.5 meter), and far (4 meter) SOD between user and mirror on the perception of personalized and self-embodied avatars. The avatars were photorealistic reconstructed using state-of-the-art photogrammetric methods. Thirty participants were repeatedly exposed to their real-time animated self-embodied avatars in each of the three SOD conditions. In each condition, the personalized avatars were repeatedly altered in their body weight, and participants were asked to judge the (1) sense of embodiment, (2) body weight perception, and (3) affective appraisal towards their avatar. We found that the different SODs are unlikely to influence any of our measures except for the perceived body weight estimation difficulty. Here, the participants judged the difficulty significantly higher for the farthest SOD. We further found that the participants' self-esteem significantly impacted their ability to modify their avatar's body weight to their current body weight and that it positively correlated with the perceived attractiveness of the avatar. Additionally, the participants' concerns about their body shape affected how eerie they perceived their avatars. Both measures influenced the perceived body weight estimation difficulty. For practical application, we conclude that the virtual mirror in embodiment scenarios can be freely placed and varied at a distance of one to four meters from the user without expecting major effects on the perception of the avatar.

@article{wolf2022distance, abstract = {Virtual reality applications employing avatar embodiment typically use virtual mirrors to allow users to perceive their digital selves not only from a first-person perspective but also from a holistic third-person view. However, due to distance-related biases such as the distance compression effect or a reduced relative rendering resolution, the self-observation distance (SOD) between the user and the virtual mirror might influence how users perceive their embodied avatar. Our article systematically investigates the effects of a short (1 meter), middle (2.5 meter), and far (4 meter) SOD between user and mirror on the perception of personalized and self-embodied avatars. The avatars were photorealistic reconstructed using state-of-the-art photogrammetric methods. Thirty participants were repeatedly exposed to their real-time animated self-embodied avatars in each of the three SOD conditions. In each condition, the personalized avatars were repeatedly altered in their body weight, and participants were asked to judge the (1) sense of embodiment, (2) body weight perception, and (3) affective appraisal towards their avatar. We found that the different SODs are unlikely to influence any of our measures except for the perceived body weight estimation difficulty. Here, the participants judged the difficulty significantly higher for the farthest SOD. We further found that the participants' self-esteem significantly impacted their ability to modify their avatar's body weight to their current body weight and that it positively correlated with the perceived attractiveness of the avatar. Additionally, the participants' concerns about their body shape affected how eerie they perceived their avatars. Both measures influenced the perceived body weight estimation difficulty. For practical application, we conclude that the virtual mirror in embodiment scenarios can be freely placed and varied at a distance of one to four meters from the user without expecting major effects on the perception of the avatar.}, author = {Wolf, Erik and Döllinger, Nina and Mal, David and Wenninger, Stephan and Bartl, Andrea and Botsch, Mario and Latoschik, Marc Erich and Wienrich, Carolin}, journal = {Frontiers in Virtual Reality}, keywords = {vitras}, title = {Does Distance Matter? Embodiment and Perception of Personalized Avatars in Relation to the Self-Observation Distance in Virtual Reality}, year = 2022 }
Seufert, A., Schweifler, R., Poignée, F., Seufert, M., Hoßfeld, T.: Waiting along the Path: How Browsing Delays Impact the QoE of Music Streaming Applications. 14th International Conference on Quality of Multimedia Experience (QoMEX) (2022).
- [ Abstract ]
- [ BibTeX ]
Streaming has become the dominant source of media consumption, which not only applies to the widely researched field of video streaming, but also to music streaming. Here, previous studies so far have only researched the impact of streaming aspects, such as stalling events or initial loading times, on the QoE of music streaming. However, when using a music streaming application, users are already facing waiting times along the click path before they can start the actual streaming. These waiting times are caused by browsing delays, e.g., during searching for songs or scrolling through playlists, and can potentially deteriorate the QoE of the music streaming application. In this work, we conduct an online QoE study to quantify the impact of these browsing delays with the support of an emulated mobile music streaming web app. We found that browsing delays have no impact on the music streaming QoE, which shows that users are able to clearly distinguish between the two main functionalities of such apps, namely, browsing and streaming. However, browsing delays significantly reduce the QoE of the entire music streaming application, to a similar extent as if QoE degradations happen during the actual streaming. This shows that both browsing and streaming are equally important and have to be considered when designing music streaming applications.

@inproceedings{info3-inproceedings-2022-13, abstract = {Streaming has become the dominant source of media consumption, which not only applies to the widely researched field of video streaming, but also to music streaming. Here, previous studies so far have only researched the impact of streaming aspects, such as stalling events or initial loading times, on the QoE of music streaming. However, when using a music streaming application, users are already facing waiting times along the click path before they can start the actual streaming. These waiting times are caused by browsing delays, e.g., during searching for songs or scrolling through playlists, and can potentially deteriorate the QoE of the music streaming application. In this work, we conduct an online QoE study to quantify the impact of these browsing delays with the support of an emulated mobile music streaming web app. We found that browsing delays have no impact on the music streaming QoE, which shows that users are able to clearly distinguish between the two main functionalities of such apps, namely, browsing and streaming. However, browsing delays significantly reduce the QoE of the entire music streaming application, to a similar extent as if QoE degradations happen during the actual streaming. This shows that both browsing and streaming are equally important and have to be considered when designing music streaming applications.}, author = {Seufert, Anika and Schweifler, Ralf and Poignée, Fabian and Seufert, Michael and Hoßfeld, Tobias}, booktitle = {14th International Conference on Quality of Multimedia Experience (QoMEX)}, keywords = {myown}, month = 9, title = {Waiting along the Path: How Browsing Delays Impact the QoE of Music Streaming Applications}, year = 2022 }
Müller, S., Brixner, T., Knote, A., Schnepp, W., Truman, S., Vetter, A., von Mammen, S.: {femtoPro}: {Ultrafast} {Phenomena} in {Virtual} {Reality}. The {International} {Conference} on {Ultrafast} {Phenomena} ({UP}) 2022 (2022), paper {W4A}.42. S. W4A.42. Optica Publishing Group (2022).
- [ Abstract ]
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We introduce “femtoPro,” an interactive simulator of an ultrafast laser laboratory in virtual reality (VR). Gaussian beam propagation as well as linear and nonlinear optical phenomena are calculated in real time on consumer-grade VR devices.

@inproceedings{mullerFemtoProUltrafastPhenomena2022, abstract = {We introduce “femtoPro,” an interactive simulator of an ultrafast laser laboratory in virtual reality (VR). Gaussian beam propagation as well as linear and nonlinear optical phenomena are calculated in real time on consumer-grade VR devices.}, author = {Müller, Stefan and Brixner, Tobias and Knote, Andreas and Schnepp, Wilhelm and Truman, Samuel and Vetter, Anne and von Mammen, Sebastian}, booktitle = {The {International} {Conference} on {Ultrafast} {Phenomena} ({UP}) 2022 (2022), paper {W4A}.42}, keywords = {myown}, month = {jul}, pages = {W4A.42}, publisher = {Optica Publishing Group}, title = {{femtoPro}: {Ultrafast} {Phenomena} in {Virtual} {Reality}}, year = 2022 }
Pfister, J., Wankerl, S., Hotho, A.: Point me to your Opinion, {S}en{P}oi. Proceedings of the 16th International Workshop on Semantic Evaluation (SemEval-2022). S. 1313–1323. Association for Computational Linguistics, Seattle, United States (2022).
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Structured Sentiment Analysis is the task of extracting sentiment tuples in a graph structure commonly from review texts. We adapt the Aspect-Based Sentiment Analysis pointer network BARTABSA to model this tuple extraction as a sequence prediction task and extend their output grammar to account for the increased complexity of Structured Sentiment Analysis. To predict structured sentiment tuples in languages other than English we swap BART for a multilingual mT5 and introduce a novel Output Length Regularization to mitigate overfitting to common target sequence lengths, thereby improving the performance of the model by up to 70{\%}. We evaluate our approach on seven datasets in five languages including a zero shot crosslingual setting.

@inproceedings{pfister-etal-2022-senpoi, abstract = {Structured Sentiment Analysis is the task of extracting sentiment tuples in a graph structure commonly from review texts. We adapt the Aspect-Based Sentiment Analysis pointer network BARTABSA to model this tuple extraction as a sequence prediction task and extend their output grammar to account for the increased complexity of Structured Sentiment Analysis. To predict structured sentiment tuples in languages other than English we swap BART for a multilingual mT5 and introduce a novel Output Length Regularization to mitigate overfitting to common target sequence lengths, thereby improving the performance of the model by up to 70{\%}. We evaluate our approach on seven datasets in five languages including a zero shot crosslingual setting.}, address = {Seattle, United States}, author = {Pfister, Jan and Wankerl, Sebastian and Hotho, Andreas}, booktitle = {Proceedings of the 16th International Workshop on Semantic Evaluation (SemEval-2022)}, keywords = {sentiment}, month = {jul}, pages = {1313–1323}, publisher = {Association for Computational Linguistics}, title = {Point me to your Opinion, {S}en{P}oi}, year = 2022 }
Firman, O., Kindermann, P., Klawitter, J., Klemz, B., Klesen, F., Wolff, A.: Outside-Obstacle Representations with All Vertices on the Outer Face. In: Angelini, P. und von Hanxleden, R. (hrsg.) Proc. 30th Int. Symp. Graph Drawing \& Network Vis. (GD’22). Springer-Verlag (2022).
- [ BibTeX ]
@inproceedings{fkkkkw-ooravof-GD22, author = {Firman, Oksana and Kindermann, Philipp and Klawitter, Jonathan and Klemz, Boris and Klesen, Felix and Wolff, Alexander}, booktitle = {Proc. 30th Int. Symp. Graph Drawing \& Network Vis. (GD'22)}, editor = {Angelini, Patrizio and von Hanxleden, Reinhard}, keywords = {myown}, publisher = {Springer-Verlag}, series = {Lecture Notes in Computer Science}, title = {Outside-Obstacle Representations with All Vertices on the Outer Face}, year = 2022 }
Oberdörfer, S., Krop, P., Straka, S., Grafe, S., Latoschik, M.E.: Fly My Little Dragon: Using AR to Learn Geometry. Proceedings of the IEEE Conference on Games (CoG ’22). S. 528–531. IEEE (2022).
- [ BibTeX ]
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@inproceedings{oberdorfer2022little, author = {Oberdörfer, Sebastian and Krop, Philipp and Straka, Samantha and Grafe, Silke and Latoschik, Marc Erich}, booktitle = {Proceedings of the IEEE Conference on Games (CoG '22)}, keywords = {oberdoerfer}, month = {August}, pages = {528-531}, publisher = {IEEE}, title = {Fly My Little Dragon: Using AR to Learn Geometry}, year = 2022 }
Metzger, F., Geißler, S., Grigorjew, A., Loh, F., Moldovan, C., Seufert, M., Hoßfeld, T.: An Introduction to Online Video Game QoS and QoE Influencing Factors. IEEE Communications Surveys & Tutorials. (2022).
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Online video games and cloud gaming are rapidly growing in pervasiveness. Their resource demands can put significant stress on the global communication infrastructure. And network conditions are amongst the chief factors that influence one's enjoyment while playing games. This makes it imperative for video games to be considered for network dimensioning, server placement or protocol development. For that reason, in this work we provide an introduction to the technical aspects of video games in general and of their network aspects in particular. This understanding forms the basis for a rich taxonomy of factors that influence and provide context to a video game's Quality of Service (QoS) and Quality of Experience (QoE). The taxonomy covers influence factors from all aspects involved in a video game, from the subjective player and game influence factors to the system and networking influence factors. Finally, this work gives an overview of conducted and ongoing research as well as future research opportunities while taking into account lessons learned from past approaches.

@article{info3-article-2022-16, abstract = {Online video games and cloud gaming are rapidly growing in pervasiveness. Their resource demands can put significant stress on the global communication infrastructure. And network conditions are amongst the chief factors that influence one's enjoyment while playing games. This makes it imperative for video games to be considered for network dimensioning, server placement or protocol development. For that reason, in this work we provide an introduction to the technical aspects of video games in general and of their network aspects in particular. This understanding forms the basis for a rich taxonomy of factors that influence and provide context to a video game's Quality of Service (QoS) and Quality of Experience (QoE). The taxonomy covers influence factors from all aspects involved in a video game, from the subjective player and game influence factors to the system and networking influence factors. Finally, this work gives an overview of conducted and ongoing research as well as future research opportunities while taking into account lessons learned from past approaches.}, author = {Metzger, Florian and Geißler, Stefan and Grigorjew, Alexej and Loh, Frank and Moldovan, Christian and Seufert, Michael and Hoßfeld, Tobias}, journal = {IEEE Communications Surveys & Tutorials}, keywords = {10.1109/COMST.2022.3177251}, month = 5, title = {An Introduction to Online Video Game QoS and QoE Influencing Factors}, year = 2022 }
Wehner, N., Amir, M., Seufert, M., Schatz, R., Hoßfeld, T.: A Vital Improvement? Relating Google’s Core Web Vitals to Actual Web QoE. 14th International Conference on Quality of Multimedia Experience (QoMEX), Best Paper Award. , Lippstadt, Germany (2022).
- [ Abstract ]
- [ BibTeX ]
Providing sophisticated Web Quality of Experience (QoE) has become paramount for web service providers and network operators alike. Due to advances in Web technologies (HTML5, responsive design, etc.), traditional Web QoE models focusing mainly on loading times have to be refined and improved. In this work, we relate Google's Core Web Vitals, a set of metrics for improving user experience, to the loading time aspects of Web QoE. To this end, we first perform objective measurements in the Web using Google's Lighthouse. To close the gap between metrics and experience, we complement these objective measurements with subjective assessment by performing multiple crowdsourcing QoE studies. In these studies, we use CWeQS, a customized framework to emulate the entire web page loading process, and ask users for their experience while controlling the Core Web Vitals. Our results suggest that the Core Web Vitals have less predictive value for Web QoE than expected and that page loading times remain the main influence factor in this context.

@inproceedings{info3-inproceedings-2022-12, abstract = {Providing sophisticated Web Quality of Experience (QoE) has become paramount for web service providers and network operators alike. Due to advances in Web technologies (HTML5, responsive design, etc.), traditional Web QoE models focusing mainly on loading times have to be refined and improved. In this work, we relate Google's Core Web Vitals, a set of metrics for improving user experience, to the loading time aspects of Web QoE. To this end, we first perform objective measurements in the Web using Google's Lighthouse. To close the gap between metrics and experience, we complement these objective measurements with subjective assessment by performing multiple crowdsourcing QoE studies. In these studies, we use CWeQS, a customized framework to emulate the entire web page loading process, and ask users for their experience while controlling the Core Web Vitals. Our results suggest that the Core Web Vitals have less predictive value for Web QoE than expected and that page loading times remain the main influence factor in this context.}, address = {Lippstadt, Germany}, author = {Wehner, Nikolas and Amir, Monisha and Seufert, Michael and Schatz, Raimund and Hoßfeld, Tobias}, booktitle = {14th International Conference on Quality of Multimedia Experience (QoMEX), Best Paper Award}, keywords = {ucn}, month = 9, title = {A Vital Improvement? Relating Google's Core Web Vitals to Actual Web QoE}, year = 2022 }
Casas, P., Wassermann, S., Seufert, M., Wehner, N., Dinica, O., Hoßfeld, T.: X-Ray Goggles for the ISP: Improving in-Network Web and App QoE Monitoring with Deep Learning. Network Traffic Measurement and Analysis Conference (TMA) (2022).
- [ Abstract ]
- [ BibTeX ]
The wide adoption of end-to-end encryption is drastically limiting the visibility Internet Service Providers (ISPs) have on the performance of the services consumed by their customers. In times of strong competition, where customer experience plays a key role in churn management, ISPs require novel solutions enabling network-wide Quality of Experience (QoE) monitoring. To this end, we present DeepQoE, a deep-learning based approach to infer the QoE of web services and mobile applications from the ISP perspective, relying exclusively on the analysis of encrypted network traffic. Using raw features derived from the encrypted stream of bytes as input to deep Convolutional Neural Networks (CNNs), DeepQoE infers the Speed Index of web browsing sessions and general mobile apps with unprecedented accuracy, improving the state of the art by more than 25%, and reducing the QoE inference error in terms of mean opinion scores by nearly 40%. DeepQoE implements a web fingerprinting solution to identify individual web browsing sessions within concurrent web pages traffic, enabling highly detailed, per web page QoE inference in practical deployments. Extensive evaluations over a large and heterogeneous dataset composed of web and app measurements, using different device types and for top-popular websites and apps, confirm the out-performance of DeepQoE over previously used shallow-learning models, as well as the deep-model generalization to different devices, web pages, apps, and network setups. DeepQoE is the first deployable system providing such a deep, highly-detailed QoE for individual web browsing and mobile apps over encrypted traffic, using deep learning models on heterogeneous measurements.

@inproceedings{info3-inproceedings-2022-11, abstract = {The wide adoption of end-to-end encryption is drastically limiting the visibility Internet Service Providers (ISPs) have on the performance of the services consumed by their customers. In times of strong competition, where customer experience plays a key role in churn management, ISPs require novel solutions enabling network-wide Quality of Experience (QoE) monitoring. To this end, we present DeepQoE, a deep-learning based approach to infer the QoE of web services and mobile applications from the ISP perspective, relying exclusively on the analysis of encrypted network traffic. Using raw features derived from the encrypted stream of bytes as input to deep Convolutional Neural Networks (CNNs), DeepQoE infers the Speed Index of web browsing sessions and general mobile apps with unprecedented accuracy, improving the state of the art by more than 25%, and reducing the QoE inference error in terms of mean opinion scores by nearly 40%. DeepQoE implements a web fingerprinting solution to identify individual web browsing sessions within concurrent web pages traffic, enabling highly detailed, per web page QoE inference in practical deployments. Extensive evaluations over a large and heterogeneous dataset composed of web and app measurements, using different device types and for top-popular websites and apps, confirm the out-performance of DeepQoE over previously used shallow-learning models, as well as the deep-model generalization to different devices, web pages, apps, and network setups. DeepQoE is the first deployable system providing such a deep, highly-detailed QoE for individual web browsing and mobile apps over encrypted traffic, using deep learning models on heterogeneous measurements.}, author = {Casas, Pedro and Wassermann, Sarah and Seufert, Michael and Wehner, Nikolas and Dinica, Olivia and Hoßfeld, Tobias}, booktitle = {Network Traffic Measurement and Analysis Conference (TMA)}, keywords = {myown}, month = 6, title = {X-Ray Goggles for the ISP: Improving in-Network Web and App QoE Monitoring with Deep Learning}, year = 2022 }
Casas, P., Wassermann, S., Wehner, N., Seufert, M., Hoßfeld, T.: Not all Web Pages are Born the Same. Content Tailored Learning for Web QoE Inference. IEEE International Symposium on Measurements & Networking (M&N 2022) (2022).
- [ Abstract ]
- [ BibTeX ]
Web Quality of Experience (QoE) monitoring is a critical task for Internet Service Providers (ISPs), especially due to the key role played by customer experience in churn management. Previously, we have tackled the problem of Web QoE inference from the ISP perspective, relying on passive measurement of encrypted network traffic and machine learning models. In this paper, we exploit the broad heterogeneity of contents embedded in web pages to improve the state of the art performance in Web QoE inference, relying on web-content learning model tailoring. By analyzing the top-500 most popular web pages of the Internet through unsupervised learning, we discover different web page content classes which realize significantly different Web QoE inference performance. We train supervised learning inference models separately for each of these classes, using the well-known Speed Index (SI) metric as proxy to Web QoE. Empirical evaluations on a large corpus of Web QoE measurements for top popular websites demonstrate that our combined content-tailored approach improves the inference performance of the SI by almost 30% with respect to previous single-model approaches, reducing the QoE inference error in terms of mean opinion scores by more than 40%.

@inproceedings{info3-inproceedings-2022-10, abstract = {Web Quality of Experience (QoE) monitoring is a critical task for Internet Service Providers (ISPs), especially due to the key role played by customer experience in churn management. Previously, we have tackled the problem of Web QoE inference from the ISP perspective, relying on passive measurement of encrypted network traffic and machine learning models. In this paper, we exploit the broad heterogeneity of contents embedded in web pages to improve the state of the art performance in Web QoE inference, relying on web-content learning model tailoring. By analyzing the top-500 most popular web pages of the Internet through unsupervised learning, we discover different web page content classes which realize significantly different Web QoE inference performance. We train supervised learning inference models separately for each of these classes, using the well-known Speed Index (SI) metric as proxy to Web QoE. Empirical evaluations on a large corpus of Web QoE measurements for top popular websites demonstrate that our combined content-tailored approach improves the inference performance of the SI by almost 30% with respect to previous single-model approaches, reducing the QoE inference error in terms of mean opinion scores by more than 40%.}, author = {Casas, Pedro and Wassermann, Sarah and Wehner, Nikolas and Seufert, Michael and Hoßfeld, Tobias}, booktitle = {IEEE International Symposium on Measurements & Networking (M&N 2022)}, keywords = {myown}, month = 7, title = {Not all Web Pages are Born the Same. Content Tailored Learning for Web QoE Inference}, year = 2022 }
Casas, P., Seufert, M., Wassermann, S., Gardlo, B., Wehner, N., Schatz, R.: DeepCrypt - Deep Learning for QoE Monitoring and Fingerprinting of User Actions in Adaptive Video Streaming. IEEE Conference on Network Softwarization (IEEE NetSoft 2022) (2022).
- [ Abstract ]
- [ BibTeX ]
We introduce DeepCrypt, a deep-learning based approach to analyze YouTube video streaming Quality of Experience (QoE) from the Internet Service Provider (ISP) perspective, relying exclusively on the analysis of encrypted network traffic. Using raw features derived on-line from the encrypted stream of bytes, DeepCrypt can infer six different video QoE indicators capturing the user-perceived performance of the service, including the initial playback delay, the number and frequency of rebuffering events, the video playback quality, the video encoding bitrate, and the number of quality changes. DeepCrypt offers deep visibility into the behavior of the end-user, enabling the fingerprinting and detection of different user actions on the video player, such as video pauses and playback scrubbing (forward, backward, out-of-buffer), offering a complete visibility on the video streaming process from in-network traffic measurements. Extensive evaluations over a large and heterogeneous dataset composed of mobile and fixed-line measurements, using the YouTube HTML5 player, the native YouTube mobile app, as well as a generic HTML5 video player built on top of open source libraries, and considering measurements collected at different ISPs, confirm the out-performance of DeepCrypt over previously used shallow-learning models, as well as the deep-model generalization to different video players and network setups. To the best of our knowledge, this is the first paper tackling such a combined QoE and user-actions approach for video streaming applications, using deep learning models over heterogeneous measurements.

@inproceedings{info3-inproceedings-2022-9, abstract = {We introduce DeepCrypt, a deep-learning based approach to analyze YouTube video streaming Quality of Experience (QoE) from the Internet Service Provider (ISP) perspective, relying exclusively on the analysis of encrypted network traffic. Using raw features derived on-line from the encrypted stream of bytes, DeepCrypt can infer six different video QoE indicators capturing the user-perceived performance of the service, including the initial playback delay, the number and frequency of rebuffering events, the video playback quality, the video encoding bitrate, and the number of quality changes. DeepCrypt offers deep visibility into the behavior of the end-user, enabling the fingerprinting and detection of different user actions on the video player, such as video pauses and playback scrubbing (forward, backward, out-of-buffer), offering a complete visibility on the video streaming process from in-network traffic measurements. Extensive evaluations over a large and heterogeneous dataset composed of mobile and fixed-line measurements, using the YouTube HTML5 player, the native YouTube mobile app, as well as a generic HTML5 video player built on top of open source libraries, and considering measurements collected at different ISPs, confirm the out-performance of DeepCrypt over previously used shallow-learning models, as well as the deep-model generalization to different video players and network setups. To the best of our knowledge, this is the first paper tackling such a combined QoE and user-actions approach for video streaming applications, using deep learning models over heterogeneous measurements.}, author = {Casas, Pedro and Seufert, Michael and Wassermann, Sarah and Gardlo, Bruno and Wehner, Nikolas and Schatz, Raimund}, booktitle = {IEEE Conference on Network Softwarization (IEEE NetSoft 2022)}, keywords = {myown}, month = 6, title = {DeepCrypt - Deep Learning for QoE Monitoring and Fingerprinting of User Actions in Adaptive Video Streaming}, year = 2022 }
Henrichs, E., Lesch, V., Straesser, M., Kounev, S., Krupitzer, C.: A literature review on optimization techniques for adaptation planning in adaptive systems: State of the art and research directions. Information and Software Technology. 149, 106940 (2022).
- [ Abstract ]
- [ BibTeX ]
- [ URL ]
Context: Recent developments in modern IT systems including internet of things, edge/fog computing, or cyber–physical systems support intelligent and seamless interaction between users and systems. This requires a reaction to changes in their environment or the system. Adaptive systems provide mechanisms for these reactions. Objective: To implement this functionality, several approaches for the planning of adaptations exist that rely on rules, utility functions, or advanced techniques, such as machine learning. As the adaptation space with possible options is often extensively huge, optimization techniques might support efficient determination of the adaptation space and identify the system’s optimal configuration. With this paper, we provide a systematic review of adaptation planning as the optimization target. Method: In this paper, we review which optimization techniques are applied for adaptation planning in adaptive systems using a systematic literature review approach. Results: We reviewed 115 paper in detail out of an initial search set of 9,588 papers. Our analysis reveals that learning techniques and genetic algorithms are by far dominant; in total, heuristics (anytime learning) are more frequently applied as exact algorithms. We observed that around 57% of the approaches target multi-objectiveness and around 30% integrate distributed optimization. As last dimension, we focused on situation-awareness, which is only supported by two approaches. Conclusion: In this paper, we provide an overview of the current state of the art of approaches that rely on optimization techniques for planning adaptations in adaptive systems and further derive open research challenges, in particular regarding the integration of distributed optimization and situation-awareness.

@article{HENRICHS2022106940, abstract = {Context: Recent developments in modern IT systems including internet of things, edge/fog computing, or cyber–physical systems support intelligent and seamless interaction between users and systems. This requires a reaction to changes in their environment or the system. Adaptive systems provide mechanisms for these reactions. Objective: To implement this functionality, several approaches for the planning of adaptations exist that rely on rules, utility functions, or advanced techniques, such as machine learning. As the adaptation space with possible options is often extensively huge, optimization techniques might support efficient determination of the adaptation space and identify the system’s optimal configuration. With this paper, we provide a systematic review of adaptation planning as the optimization target. Method: In this paper, we review which optimization techniques are applied for adaptation planning in adaptive systems using a systematic literature review approach. Results: We reviewed 115 paper in detail out of an initial search set of 9,588 papers. Our analysis reveals that learning techniques and genetic algorithms are by far dominant; in total, heuristics (anytime learning) are more frequently applied as exact algorithms. We observed that around 57% of the approaches target multi-objectiveness and around 30% integrate distributed optimization. As last dimension, we focused on situation-awareness, which is only supported by two approaches. Conclusion: In this paper, we provide an overview of the current state of the art of approaches that rely on optimization techniques for planning adaptations in adaptive systems and further derive open research challenges, in particular regarding the integration of distributed optimization and situation-awareness.}, author = {Henrichs, Elia and Lesch, Veronika and Straesser, Martin and Kounev, Samuel and Krupitzer, Christian}, journal = {Information and Software Technology}, keywords = {myown}, pages = 106940, title = {A literature review on optimization techniques for adaptation planning in adaptive systems: State of the art and research directions}, volume = 149, year = 2022 }
Vomhoff, V., Geißler, S., Hoßfeld, T.: Identification of Signaling Patterns in Mobile IoT Signaling Traffic. WueWoWAS 22 - KuVS Fachgespräch - Würzburg Workshop on Next-Generation Communication Networks (2022).
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@inproceedings{info3-inproceedings-2022-8, author = {Vomhoff, Viktoria and Geißler, Stefan and Hoßfeld, Tobias}, booktitle = {WueWoWAS 22 - KuVS Fachgespräch - Würzburg Workshop on Next-Generation Communication Networks}, keywords = {can}, month = 7, title = {Identification of Signaling Patterns in Mobile IoT Signaling Traffic}, year = 2022 }
Raffeck, S., Geißler, S., Hoßfeld, T.: DBM: Decentralized Burst Mitigation for Self-Organizing LoRa Deployments. KuVS Fachgespräch - Würzburg Workshop on Modeling, Analysis and Simulation of Next-Generation Communication Networks 2022 (2022).
- [ BibTeX ]
@inproceedings{info3-inproceedings-2022-7, author = {Raffeck, Simon and Geißler, Stefan and Hoßfeld, Tobias}, booktitle = {KuVS Fachgespräch - Würzburg Workshop on Modeling, Analysis and Simulation of Next-Generation Communication Networks 2022}, keywords = {can}, month = 7, title = {DBM: Decentralized Burst Mitigation for Self-Organizing LoRa Deployments}, year = 2022 }
Chaplick, S., Felsner, S., Kindermann, P., Klawitter, J., Rutter, I., Wolff, A.: Simple Algorithms for Partial and Simultaneous Rectangular Duals with Given Contact Orientations. Theoretical Computer Science. 919, 66–74 (2022).
- [ Abstract ]
- [ BibTeX ]
- [ DOI ]
A rectangular dual of a graph $G$ is a contact representation of $G$ by axis-aligned rectangles such that (i) no four rectangles share a point and (ii) the union of all rectangles is a rectangle. The \emph{partial representation extension problem} for rectangular duals asks whether a given partial rectangular dual can be extended to a rectangular dual, that is, whether there exists a rectangular dual where some vertices are represented by prescribed rectangles. The \emph{simultaneous representation problem} for rectangular duals asks whether two (or more) given graphs that share a subgraph admit rectangular duals that coincide on the shared subgraph. Combinatorially, a rectangular dual can be described by a regular edge labeling (REL), which determines the orientations of the rectangle contacts. \par We describe linear-time algorithms for the partial representation extension problem and the simultaneous representation problem for rectangular duals when each input graph is given together with a REL. Both algorithms are based on formulations as linear programs, yet they have geometric interpretations and can be seen as extensions of the classic algorithm by Kant and He that computes a rectangular dual for a given graph.

@article{cfkkrw-sapsr-TCS22, abstract = {A rectangular dual of a graph $G$ is a contact representation of $G$ by axis-aligned rectangles such that (i) no four rectangles share a point and (ii) the union of all rectangles is a rectangle. The \emph{partial representation extension problem} for rectangular duals asks whether a given partial rectangular dual can be extended to a rectangular dual, that is, whether there exists a rectangular dual where some vertices are represented by prescribed rectangles. The \emph{simultaneous representation problem} for rectangular duals asks whether two (or more) given graphs that share a subgraph admit rectangular duals that coincide on the shared subgraph. Combinatorially, a rectangular dual can be described by a regular edge labeling (REL), which determines the orientations of the rectangle contacts. \par We describe linear-time algorithms for the partial representation extension problem and the simultaneous representation problem for rectangular duals when each input graph is given together with a REL. Both algorithms are based on formulations as linear programs, yet they have geometric interpretations and can be seen as extensions of the classic algorithm by Kant and He that computes a rectangular dual for a given graph.}, author = {Chaplick, Steven and Felsner, Stefan and Kindermann, Philipp and Klawitter, Jonathan and Rutter, Ignaz and Wolff, Alexander}, journal = {Theoretical Computer Science}, keywords = {simultaneous_representation}, pages = {66–74}, title = {Simple Algorithms for Partial and Simultaneous Rectangular Duals with Given Contact Orientations}, volume = 919, year = 2022 }
Zink, J., Walter, J., Baumeister, J., Wolff, A.: Layered drawing of undirected graphs with generalized port constraints. Computational Geometry: Theory and Applications. 105-106, 101886 (2022).
- [ Abstract ]
- [ BibTeX ]
The aim of this research is a practical method to draw cable plans of complex machines. Such plans consist of electronic components and cables connecting specific ports of the components. Since the machines are configured for each client individually, cable plans need to be drawn automatically. The drawings must be well readable so that technicians can use them to debug the machines. In order to model plug sockets, we introduce port groups; within a group, ports can change their position (which we use to improve the aesthetics of the layout), but together the ports of a group must form a contiguous block. We approach the problem of drawing such cable plans by extending the well-known Sugiyama framework such that it incorporates ports and port groups. Since the framework assumes directed graphs, we propose several ways to orient the edges of the given undirected graph. We compare these methods experimentally, both on real-world data and synthetic data that carefully simulates real-world data. We measure the aesthetics of the resulting drawings by counting bends and crossings. Using these metrics, we experimentally compare our approach to Kieler JVLC 2014, a library for drawing graphs in the presence of port constraints. Our method produced 10--30 \% fewer crossings, while it performed equally well or slightly worse than Kieler with respect to the number of bends and the time used to compute a drawing.

@article{ZINK2022101886, abstract = {The aim of this research is a practical method to draw cable plans of complex machines. Such plans consist of electronic components and cables connecting specific ports of the components. Since the machines are configured for each client individually, cable plans need to be drawn automatically. The drawings must be well readable so that technicians can use them to debug the machines. In order to model plug sockets, we introduce port groups; within a group, ports can change their position (which we use to improve the aesthetics of the layout), but together the ports of a group must form a contiguous block. We approach the problem of drawing such cable plans by extending the well-known Sugiyama framework such that it incorporates ports and port groups. Since the framework assumes directed graphs, we propose several ways to orient the edges of the given undirected graph. We compare these methods experimentally, both on real-world data and synthetic data that carefully simulates real-world data. We measure the aesthetics of the resulting drawings by counting bends and crossings. Using these metrics, we experimentally compare our approach to Kieler JVLC 2014, a library for drawing graphs in the presence of port constraints. Our method produced 10–30 \% fewer crossings, while it performed equally well or slightly worse than Kieler with respect to the number of bends and the time used to compute a drawing.}, author = {Zink, Johannes and Walter, Julian and Baumeister, Joachim and Wolff, Alexander}, journal = {Computational Geometry: Theory and Applications}, keywords = {rokt}, pages = 101886, title = {Layered drawing of undirected graphs with generalized port constraints}, volume = {105-106}, year = 2022 }
Geißler, S.: Performance Evaluation of Next-Generation Data Plane Architectures and their Components, (2022).
- [ Abstract ]
- [ BibTeX ]
In this doctoral thesis we cover the performance evaluation of next generation data plane architectures, comprised of complex software as well as programmable hardware components that allow fine granular configuration. In the scope of the thesis we propose mechanisms to monitor the performance of singular components and model key performance indicators of software based packet processing solutions. We present novel approaches towards network abstraction that allow the integration of heterogeneous data plane technologies into a singular network while maintaining total transparency between control and data plane. Finally, we investigate a full, complex system consisting of multiple software-based solutions and perform a detailed performance analysis. We employ simulative approaches to investigate overload control mechanisms that allow efficient operation under adversary conditions. The contributions of this work build the foundation for future research in the areas of network softwarization and network function virtualization.

@phdthesis{info3-dissertation-2022-1, abstract = {In this doctoral thesis we cover the performance evaluation of next generation data plane architectures, comprised of complex software as well as programmable hardware components that allow fine granular configuration. In the scope of the thesis we propose mechanisms to monitor the performance of singular components and model key performance indicators of software based packet processing solutions. We present novel approaches towards network abstraction that allow the integration of heterogeneous data plane technologies into a singular network while maintaining total transparency between control and data plane. Finally, we investigate a full, complex system consisting of multiple software-based solutions and perform a detailed performance analysis. We employ simulative approaches to investigate overload control mechanisms that allow efficient operation under adversary conditions. The contributions of this work build the foundation for future research in the areas of network softwarization and network function virtualization.}, author = {Geißler, Stefan}, keywords = {ngn}, month = 4, school = {University of Würzburg}, title = {Performance Evaluation of Next-Generation Data Plane Architectures and their Components}, year = 2022 }
Raffeck, S., Geißler, S., Krolikowski, M., Gebert, S., Hoßfeld, T.: Anonymized GTP Tunnel Trace in Mobile IoT, (2022).
- [ Abstract ]
- [ BibTeX ]
Extensive dataset containing one whole month of create and delete events as well as the total, received, and transmitted volume of devices. We obtained data tunnel related events and volume values over 30 days in October 2021. In total the dataset contains a sample of 500000 unique devices that generate 155 million individual data tunnels.

@misc{info3-misc-2022-1, abstract = {Extensive dataset containing one whole month of create and delete events as well as the total, received, and transmitted volume of devices. We obtained data tunnel related events and volume values over 30 days in October 2021. In total the dataset contains a sample of 500000 unique devices that generate 155 million individual data tunnels.}, author = {Raffeck, Simon and Geißler, Stefan and Krolikowski, Michael and Gebert, Steffen and Hoßfeld, Tobias}, howpublished = {https://zenodo.org/record/6045708}, keywords = {can}, month = 2, title = {Anonymized GTP Tunnel Trace in Mobile IoT}, year = 2022 }
Prantl, T., Engel, S., Bauer, A., Ben Yahya, A.E., Herrnleben, S., Iffländer, L., Dmitrienko, A., Kounev, S.: An Experience Report on the Suitability of a Distributed Group Encryption Scheme for an IoT Use Case. 2022 IEEE 95th Vehicular Technology Conference (VTC2022). IEEE (2022).
- [ BibTeX ]
@inproceedings{PrEnBaAlHeIfDmKo2022-IoT/CPS-DistributedGroupEncryption, author = {Prantl, Thomas and Engel, Simon and Bauer, Andre and Ben Yahya, Ala Eddine and Herrnleben, Stefan and Iffländer, Lukas and Dmitrienko, Alexandra and Kounev, Samuel}, booktitle = {2022 IEEE 95th Vehicular Technology Conference (VTC2022)}, keywords = {myown}, organization = {IEEE}, title = {An Experience Report on the Suitability of a Distributed Group Encryption Scheme for an IoT Use Case}, year = 2022 }
Ganal, E., Heimbrock, M., Schaper, P., Lugrin, B.: Don’t Touch This! - Investigating the Potential of Visualizing Touched Surfaces on the Consideration of Behavior Change. In: Baghaei, N., Vassileva, J., Ali, R., und Oyibo, K. (hrsg.) Persuasive Technology 2022. Springer International Publishing (2022).
- [ BibTeX ]
@inproceedings{ganal2022touch, author = {Ganal, E. and Heimbrock, M. and Schaper, P. and Lugrin, B.}, booktitle = {Persuasive Technology 2022}, editor = {Baghaei, N. and Vassileva, J. and Ali, R. and Oyibo, K.}, keywords = {schaper}, publisher = {Springer International Publishing}, title = {Don’t Touch This! - Investigating the Potential of Visualizing Touched Surfaces on the Consideration of Behavior Change}, year = 2022 }
Krop, P., Straka, S., Ullrich, M., Ertl, M., Latoschik, M.E.: IT-Supported Request Management for Clinical Radiology: Contextual Design and Remote Prototype Testing. CHI Conference on Human Factors in Computing Systems Extended Abstracts. S. 1–8. Association for Computing Machinery, New York, NY, USA (2022).
- [ Abstract ]
- [ BibTeX ]
- [ URL ]
- [ DOI ]
Management of radiology requests in larger clinical contexts is characterized by a complex and distributed workflow. In our partner hospital, representing many similar clinics, these processes often still rely on exchanging physical papers and forms, making patient or case data challenging to access. This often leads to phone calls with long waiting queues, which are time-inefficient and result in frequent interrupts. We report on a user-centered design approach based on Rapid Contextual Design with an additional focus group to optimize and iteratively develop a new workflow. Participants found our prototypes fast and intuitive, the design clean and consistent, relevant information easy to access, and the request process fast and easy. Due to the COVID pandemic, we switched to remote prototype testing, which yielded equally good feedback and increased the participation rate. In the end, we propose best practices for remote prototype testing in hospitals with complex and distributed workflows.

@inproceedings{krop2022a, abstract = {Management of radiology requests in larger clinical contexts is characterized by a complex and distributed workflow. In our partner hospital, representing many similar clinics, these processes often still rely on exchanging physical papers and forms, making patient or case data challenging to access. This often leads to phone calls with long waiting queues, which are time-inefficient and result in frequent interrupts. We report on a user-centered design approach based on Rapid Contextual Design with an additional focus group to optimize and iteratively develop a new workflow. Participants found our prototypes fast and intuitive, the design clean and consistent, relevant information easy to access, and the request process fast and easy. Due to the COVID pandemic, we switched to remote prototype testing, which yielded equally good feedback and increased the participation rate. In the end, we propose best practices for remote prototype testing in hospitals with complex and distributed workflows.}, address = {New York, NY, USA}, author = {Krop, Philipp and Straka, Samantha and Ullrich, Melanie and Ertl, Maximilian and Latoschik, Marc Erich}, booktitle = {CHI Conference on Human Factors in Computing Systems Extended Abstracts}, keywords = {straka}, month = {April}, number = 45, pages = {1-8}, publisher = {Association for Computing Machinery}, series = {CHI EA '22}, title = {IT-Supported Request Management for Clinical Radiology: Contextual Design and Remote Prototype Testing}, year = 2022 }
Zimmerer, C., Fischbach, M., Latoschik, M.E.: A Case Study on the Rapid Development of Natural and Synergistic Multimodal Interfaces for XR Use-Cases. CHI Conference on Human Factors in Computing Systems Extended Abstracts. Association for Computing Machinery, New Orleans, LA, USA (2022).
- [ Abstract ]
- [ BibTeX ]
- [ URL ]
- [ DOI ]
Multimodal Interfaces (MMIs) supporting the synergistic use of natural modalities like speech and gesture have been conceived as promising for spatial or 3D interactions, e.g., in Virtual, Augmented, and Mixed Reality (XR for short). Yet, the currently prevailing user interfaces are unimodal. Commercially available software platforms like the Unity or Unreal game engines simplify the complexity of developing XR applications through appropriate tool support. They provide ready-to-use device integration, e.g., for 3D controllers or motion tracking, and according interaction techniques such as menus, (3D) point-and-click, or even simple symbolic gestures to rapidly develop unimodal interfaces. A comparable tool support is yet missing for multimodal solutions in this and similar areas. We believe that this hinders user-centered research based on rapid prototyping of MMIs, the identification and formulation of practical design guidelines, the development of killer applications highlighting the power of MMIs, and ultimately a widespread adoption of MMIs. This article investigates potential reasons for the ongoing uncommonness of MMIs. Our case study illustrates and analyzes lessons learned during the development and application of a toolchain that supports rapid development of natural and synergistic MMIs for XR use-cases. We analyze the toolchain in terms of developer usability, development time, and MMI customization. This analysis is based on the knowledge gained in years of research and academic education. Specifically, it reflects on the development of appropriate MMI tools and their application in various demo use-cases, in user-centered research, and in the lab work of a mandatory MMI course of an HCI master’s program. The derived insights highlight successful choices made as well as potential areas for improvement.

@inproceedings{10.1145/3491101.3503552, abstract = {Multimodal Interfaces (MMIs) supporting the synergistic use of natural modalities like speech and gesture have been conceived as promising for spatial or 3D interactions, e.g., in Virtual, Augmented, and Mixed Reality (XR for short). Yet, the currently prevailing user interfaces are unimodal. Commercially available software platforms like the Unity or Unreal game engines simplify the complexity of developing XR applications through appropriate tool support. They provide ready-to-use device integration, e.g., for 3D controllers or motion tracking, and according interaction techniques such as menus, (3D) point-and-click, or even simple symbolic gestures to rapidly develop unimodal interfaces. A comparable tool support is yet missing for multimodal solutions in this and similar areas. We believe that this hinders user-centered research based on rapid prototyping of MMIs, the identification and formulation of practical design guidelines, the development of killer applications highlighting the power of MMIs, and ultimately a widespread adoption of MMIs. This article investigates potential reasons for the ongoing uncommonness of MMIs. Our case study illustrates and analyzes lessons learned during the development and application of a toolchain that supports rapid development of natural and synergistic MMIs for XR use-cases. We analyze the toolchain in terms of developer usability, development time, and MMI customization. This analysis is based on the knowledge gained in years of research and academic education. Specifically, it reflects on the development of appropriate MMI tools and their application in various demo use-cases, in user-centered research, and in the lab work of a mandatory MMI course of an HCI master’s program. The derived insights highlight successful choices made as well as potential areas for improvement.}, address = {New York, NY, USA}, author = {Zimmerer, Chris and Fischbach, Martin and Latoschik, Marc Erich}, booktitle = {CHI Conference on Human Factors in Computing Systems Extended Abstracts}, keywords = {myown}, publisher = {Association for Computing Machinery}, series = {CHI EA '22}, title = {A Case Study on the Rapid Development of Natural and Synergistic Multimodal Interfaces for XR Use-Cases}, year = 2022 }
Hoßfeld, T., Raffeck, S., Loh, F., Geißler, S.: Analytical Model for the Energy Efficiency in Low Power IoT Deployments. 1st International Workshop on Network Energy Efficiency in the Softwarization Era (2022).
- [ Abstract ]
- [ BibTeX ]
The recent rise of the Internet of Things (IoT) has given way to numerous challenges and research questions. One of the most critical issues in the area of low powered devices is the question of energy efficiency. Here, technologies like LoRa or Zigbee emerged, promising low power consumption while maintaining adequate performance. However, even when using these tailor made technologies, several configuration aspects need to be taken into account to provide high performance, energy efficient operation. To this end, we propose a generic model to compute the energy efficiency of wireless sensors under the assumption of perfect CSMA/CA channel access. We present numerical results for a typical LoRa device and highlight extensions towards other channel access mechanisms. Finally, we apply Kleinrock's power metric to obtain ideal system configurations for varying load parameters.

@inproceedings{info3-inproceedings-2022-6, abstract = {The recent rise of the Internet of Things (IoT) has given way to numerous challenges and research questions. One of the most critical issues in the area of low powered devices is the question of energy efficiency. Here, technologies like LoRa or Zigbee emerged, promising low power consumption while maintaining adequate performance. However, even when using these tailor made technologies, several configuration aspects need to be taken into account to provide high performance, energy efficient operation. To this end, we propose a generic model to compute the energy efficiency of wireless sensors under the assumption of perfect CSMA/CA channel access. We present numerical results for a typical LoRa device and highlight extensions towards other channel access mechanisms. Finally, we apply Kleinrock's power metric to obtain ideal system configurations for varying load parameters.}, author = {Hoßfeld, Tobias and Raffeck, Simon and Loh, Frank and Geißler, Stefan}, booktitle = {1st International Workshop on Network Energy Efficiency in the Softwarization Era}, keywords = {can}, month = 6, title = {Analytical Model for the Energy Efficiency in Low Power IoT Deployments}, year = 2022 }
Zimmerer, C., Krop, P., Fischbach, M., Latoschik, M.E.: Reducing the Cognitive Load of Playing a Digital Tabletop Game with a Multimodal Interface. CHI Conference on Human Factors in Computing Systems. Association for Computing Machinery, New Orleans, LA, USA (2022).
- [ Abstract ]
- [ BibTeX ]
- [ URL ]
- [ DOI ]
Multimodal Interfaces (MMIs) combining speech and spatial input have the potential to elicit minimal cognitive load. Low cognitive load increases effectiveness as well as user satisfaction and is regarded as an important aspect of intuitive use. While this potential has been extensively theorized in the research community, experiments that provide supporting observations based on functional interfaces are still scarce. In particular, there is a lack of studies comparing the commonly used Unimodal Interfaces (UMIs) with theoretically superior synergistic MMI alternatives. Yet, these studies are an essential prerequisite for generalizing results, developing practice-oriented guidelines, and ultimately exploiting the potential of MMIs in a broader range of applications. This work contributes a novel observation towards the resolution of this shortcoming in the context of the following combination of applied interaction techniques, tasks, application domain, and technology: We present a comprehensive evaluation of a synergistic speech & touch MMI and a touch-only menu-based UMI (interaction techniques) for selection and system control tasks in a digital tabletop game (application domain) on an interactive surface (technology). Cognitive load, user experience, and intuitive use are evaluated, with the former being assessed by means of the dual-task paradigm. Our experiment shows that the implemented MMI causes significantly less cognitive load and is perceived significantly more usable and intuitive than the UMI. Based on our results, we derive recommendations for the interface design of digital tabletop games on interactive surfaces. Further, we argue that our results and design recommendations are suitable to be generalized to other application domains on interactive surfaces for selection and system control tasks.

@inproceedings{10.1145/3491102.3502062, abstract = {Multimodal Interfaces (MMIs) combining speech and spatial input have the potential to elicit minimal cognitive load. Low cognitive load increases effectiveness as well as user satisfaction and is regarded as an important aspect of intuitive use. While this potential has been extensively theorized in the research community, experiments that provide supporting observations based on functional interfaces are still scarce. In particular, there is a lack of studies comparing the commonly used Unimodal Interfaces (UMIs) with theoretically superior synergistic MMI alternatives. Yet, these studies are an essential prerequisite for generalizing results, developing practice-oriented guidelines, and ultimately exploiting the potential of MMIs in a broader range of applications. This work contributes a novel observation towards the resolution of this shortcoming in the context of the following combination of applied interaction techniques, tasks, application domain, and technology: We present a comprehensive evaluation of a synergistic speech & touch MMI and a touch-only menu-based UMI (interaction techniques) for selection and system control tasks in a digital tabletop game (application domain) on an interactive surface (technology). Cognitive load, user experience, and intuitive use are evaluated, with the former being assessed by means of the dual-task paradigm. Our experiment shows that the implemented MMI causes significantly less cognitive load and is perceived significantly more usable and intuitive than the UMI. Based on our results, we derive recommendations for the interface design of digital tabletop games on interactive surfaces. Further, we argue that our results and design recommendations are suitable to be generalized to other application domains on interactive surfaces for selection and system control tasks.}, address = {New York, NY, USA}, author = {Zimmerer, Chris and Krop, Philipp and Fischbach, Martin and Latoschik, Marc Erich}, booktitle = {CHI Conference on Human Factors in Computing Systems}, keywords = {myown}, publisher = {Association for Computing Machinery}, series = {CHI '22}, title = {Reducing the Cognitive Load of Playing a Digital Tabletop Game with a Multimodal Interface}, year = 2022 }
Riedmann, A., Schaper, P., Lugrin, B.: Integration of a social robot and gamification in adult learning and effects on motivation, engagement and performance. AI & Society. (2022).
- [ BibTeX ]
- [ DOI ]
@article{Riedmann_2022, author = {Riedmann, Anna and Schaper, Philipp and Lugrin, Birgit}, journal = {AI & Society}, keywords = {schaper}, publisher = {Springer}, title = {Integration of a social robot and gamification in adult learning and effects on motivation, engagement and performance}, year = 2022 }
Riedmann, A., Schaper, P., Donnermann, M., Lein, M., Steinhaeusser, S.C., Karageorgos, P., Müller, B., Richter, T., Lugrin, B.: Iteratively Digitizing an Analogue Syllable-Based Reading Intervention. Interacting with Computers. (2022).
- [ BibTeX ]
- [ DOI ]
@article{2022, author = {Riedmann, Anna and Schaper, Philipp and Donnermann, Melissa and Lein, Martina and Steinhaeusser, Sophia C. and Karageorgos, Panagiotis and Müller, Bettina and Richter, Tobias and Lugrin, Birgit}, journal = {Interacting with Computers}, keywords = {steinhaeusser}, publisher = {Oxford University Press}, title = {Iteratively Digitizing an Analogue Syllable-Based Reading Intervention}, year = 2022 }
Schaper, P., Riedmann, A., Semineth, M., Lugrin, B.: Addressing Motivation in an E-Learning Scenario by applying Narration and Choice. Proceedings of the 35th British Human-Computer Interaction Conference (BCS HCI 22) (2022).
- [ BibTeX ]
@inproceedings{schaper2022addressing, author = {Schaper, Philipp and Riedmann, Anna and Semineth, Miriam and Lugrin, Birgit}, booktitle = {Proceedings of the 35th British Human-Computer Interaction Conference (BCS HCI 22)}, keywords = {schaper}, title = {Addressing Motivation in an E-Learning Scenario by applying Narration and Choice}, year = 2022 }
Evans, W.S., Fleszar, K., Kindermann, P., Saeedi, N., Shin, C.-S., Wolff, A.: Minimum Rectilinear Polygons for Given Angle Sequences. Computational Geometry: Theory and Applications. 100, 1–39 (2022).
- [ Abstract ]
- [ BibTeX ]
- [ DOI ]
A rectilinear polygon is a simple polygon whose edges are axis-aligned. Walking counterclockwise on the boundary of such a polygon yields a sequence of left turns and right turns. The number of left turns always equals the number of right turns plus four. It is known that any such sequence can be realized by a rectilinear polygon. \par In this paper, we consider the problem of finding realizations that minimize the perimeter or the area of the polygon or the area of the bounding box of the polygon. We show that all three problems are NP-hard in general. This answers an open question of Patrignani [CGTA 2001], who showed that it is NP-hard to minimize the area of the bounding box of an orthogonal drawing of a given planar graph. We also show that realizing a polyline within a bounding box of minimum area (or within a fixed given rectangle) is NP-hard. Then we consider the special cases of x-monotone and xy-monotone rectilinear polygons. For these, we can optimize the three objectives efficiently.

@article{efkssw-mrpga-CGTA22, abstract = {A rectilinear polygon is a simple polygon whose edges are axis-aligned. Walking counterclockwise on the boundary of such a polygon yields a sequence of left turns and right turns. The number of left turns always equals the number of right turns plus four. It is known that any such sequence can be realized by a rectilinear polygon. \par In this paper, we consider the problem of finding realizations that minimize the perimeter or the area of the polygon or the area of the bounding box of the polygon. We show that all three problems are NP-hard in general. This answers an open question of Patrignani [CGTA 2001], who showed that it is NP-hard to minimize the area of the bounding box of an orthogonal drawing of a given planar graph. We also show that realizing a polyline within a bounding box of minimum area (or within a fixed given rectangle) is NP-hard. Then we consider the special cases of x-monotone and xy-monotone rectilinear polygons. For these, we can optimize the three objectives efficiently.}, author = {Evans, William S. and Fleszar, Krzysztof and Kindermann, Philipp and Saeedi, Noushin and Shin, Chan-Su and Wolff, Alexander}, journal = {Computational Geometry: Theory and Applications}, keywords = {myown}, number = 101820, pages = {1–39}, title = {Minimum Rectilinear Polygons for Given Angle Sequences}, volume = 100, year = 2022 }
Döllinger, N., Göttfert, C., Wolf, E., Mal, D., Latoschik, M.E., Wienrich, C.: Analyzing Eye Tracking Data in Mirror Exposure. Proceedings of the Conference on Mensch und Computer (2022).
- [ Abstract ]
- [ BibTeX ]
- [ URL ]
Mirror exposure is an important method in the treatment of body image disturbances. Eye tracking can support the unaffected assessment of attention biases during mirror exposure. However, the analysis of eye tracking data in mirror exposure comes with various difficulties and is associated with a high manual workload during data processing. We present an automated data processing framework that enables us to determine any body part as an area of interest without placing markers on the bodies of participants. A short, formative user study proved the quality compared to the gold standard. The automatic processing and openness for different systems allow a broad range of applications.

@inproceedings{dollinger2022eyetracking, abstract = {Mirror exposure is an important method in the treatment of body image disturbances. Eye tracking can support the unaffected assessment of attention biases during mirror exposure. However, the analysis of eye tracking data in mirror exposure comes with various difficulties and is associated with a high manual workload during data processing. We present an automated data processing framework that enables us to determine any body part as an area of interest without placing markers on the bodies of participants. A short, formative user study proved the quality compared to the gold standard. The automatic processing and openness for different systems allow a broad range of applications.}, author = {Döllinger, Nina and Göttfert, Christopher and Wolf, Erik and Mal, David and Latoschik, Marc Erich and Wienrich, Carolin}, booktitle = {Proceedings of the Conference on Mensch und Computer}, keywords = {vitras}, title = {Analyzing Eye Tracking Data in Mirror Exposure}, year = 2022 }
Wienrich, C., Obremski, D., Israel, J.H.: Repeated experience or a virtual nose to reduce simulator sickness? {\textendash} Investigating prediction of the sensorial conflict theory and the rest-frame hypothesis in two virtual games. Entertainment Computing. 43, 100514 (2022).
- [ BibTeX ]
- [ URL ]
- [ DOI ]
@article{Wienrich_2022, author = {Wienrich, Carolin and Obremski, David and Israel, Johann Habakuk}, journal = {Entertainment Computing}, keywords = {obremski}, month = {aug}, pages = 100514, publisher = {Elsevier {BV}}, title = {Repeated experience or a virtual nose to reduce simulator sickness? {\textendash} Investigating prediction of the sensorial conflict theory and the rest-frame hypothesis in two virtual games}, volume = 43, year = 2022 }
Straesser, M., Haas, P.: Leveraging Kubernetes Source Code for Performance Simulation. (2022).
- [ BibTeX ]
- [ URL ]
@presentation{straesser2022leveraging, author = {Straesser, Martin and Haas, Patrick}, keywords = {myown}, title = {Leveraging Kubernetes Source Code for Performance Simulation}, year = 2022 }
Keppler, S., Döllinger, N., Wienrich, C., Latoschik, M.E., Israel, J.H.: Self-Touch: An Immersive Interaction-Technique to Enhance Body Awareness. i-com. 21, 329–337 (2022).
- [ Abstract ]
- [ BibTeX ]
- [ URL ]
- [ DOI ]
Physical well-being depends essentially on how the own body is perceived. A missing correspondence between the perception of one’s own body and reality can be distressing and eventually lead to mental illness. The touch of the own body is a multi-sensory experience to strengthen the feeling of the own body. We have developed an interaction technique that allows the self-touch of the own body in an immersive environment to support therapy procedures. Through additional visual feedback, we want to strengthen the feeling for the own body to achieve a sustainable effect in the own body perception. We conducted an expert evaluation to analyse the potential impact of our application and to localize and fix possible usability problems. The experts noted the ease of understanding and suitability of the interaction technique for increasing body awareness. However, the technical challenges such as stable and accurate body tracking were also mentioned. In addition, new ideas were given that would further support body awareness.

@article{KepplerDöllingerWienrichLatoschikIsrael+2022+329+337, abstract = {Physical well-being depends essentially on how the own body is perceived. A missing correspondence between the perception of one’s own body and reality can be distressing and eventually lead to mental illness. The touch of the own body is a multi-sensory experience to strengthen the feeling of the own body. We have developed an interaction technique that allows the self-touch of the own body in an immersive environment to support therapy procedures. Through additional visual feedback, we want to strengthen the feeling for the own body to achieve a sustainable effect in the own body perception. We conducted an expert evaluation to analyse the potential impact of our application and to localize and fix possible usability problems. The experts noted the ease of understanding and suitability of the interaction technique for increasing body awareness. However, the technical challenges such as stable and accurate body tracking were also mentioned. In addition, new ideas were given that would further support body awareness.}, author = {Keppler, Sebastian and Döllinger, Nina and Wienrich, Carolin and Latoschik, Marc Erich and Israel, Johann Habakuk}, journal = {i-com}, keywords = {vitras}, number = 3, pages = {329–337}, title = {Self-Touch: An Immersive Interaction-Technique to Enhance Body Awareness}, volume = 21, year = 2022 }
Frank, S., Wagner, L., Hakamian, A., Straesser, M., van Hoorn, A.: MiSim: A Simulator for Resilience Assessment of Microservice-based Architectures. Proceedings of the IEEE 22nd International Conference on Software Quality, Reliability, and Security (QRS~2022). IEEE (2022).
- [ BibTeX ]
@inproceedings{FrankWagnerHakamianStraesserVanHoorn2022MiSim, author = {Frank, Sebastian and Wagner, Lion and Hakamian, Alireza and Straesser, Martin and van Hoorn, Andr\’e}, booktitle = {Proceedings of the IEEE 22nd International Conference on Software Quality, Reliability, and Security (QRS 2022)}, keywords = {myown}, note = {In print.}, publisher = {IEEE}, title = {MiSim: A Simulator for Resilience Assessment of Microservice-based Architectures}, year = 2022 }
Menzel, T., Botsch, M., Latoschik, M.E.: Automated Blendshape Personalization for Faithful Face Animations Using Commodity Smartphones. 28th ACM Symposium on Virtual Reality Software and Technology (VRST ’22). (2022).
- [ BibTeX ]
- [ URL ]
@article{menzel2022automated, author = {Menzel, Timo and Botsch, Mario and Latoschik, Marc Erich}, journal = {28th ACM Symposium on Virtual Reality Software and Technology (VRST ’22)}, keywords = {via-vr}, title = {Automated Blendshape Personalization for Faithful Face Animations Using Commodity Smartphones}, year = 2022 }
Lin, J., Latoschik, M.E.: Digital body, identity and privacy in social virtual reality: A systematic review. Frontiers in Virtual Reality. 3, (2022).
- [ Abstract ]
- [ BibTeX ]
- [ URL ]
- [ DOI ]
Social Virtual Reality (social VR or SVR) provides digital spaces for diverse human activities, social interactions, and embodied face-to-face encounters. While our digital bodies in SVR can in general be of almost any conceivable appearance, individualized or even personalized avatars bearing users’ likeness recently became an interesting research topic. Such digital bodies show a great potential to enhance the authenticity of social VR citizens and increase the trustworthiness of interpersonal interaction. However, using such digital bodies might expose users to privacy and identity issues such as identity theft: For instance, how do we know whether the avatars we encounter in the virtual world are who they claim to be? Safeguarding users’ identities and privacy, and preventing harm from identity infringement, are crucial to the future of social VR. This article provides a systematic review on the protection of users’ identity and privacy in social VR, with a specific focus on digital bodies. Based on 814 sources, we identified and analyzed 49 papers that either: 1) discuss or raise concerns about the addressed issues, 2) provide technologies and potential solutions for protecting digital bodies, or 3) examine the relationship between the digital bodies and users of social VR citizens. We notice a severe lack of research and attention on the addressed topic and identify several research gaps that need to be filled. While some legal and ethical concerns about the potential identity issues of the digital bodies have been raised, and despite some progress in specific areas such as user authentication has been made, little research has proposed practical solutions. Finally, we suggest potential future research directions for digital body protection and include relevant research that might provide insights. We hope this work could provide a good overview of the existing discussion, potential solutions, and future directions for researchers with similar concerns. We also wish to draw attention to identity and privacy issues in social VR and call for interdisciplinary collaboration.

@article{lin2022digital, abstract = {Social Virtual Reality (social VR or SVR) provides digital spaces for diverse human activities, social interactions, and embodied face-to-face encounters. While our digital bodies in SVR can in general be of almost any conceivable appearance, individualized or even personalized avatars bearing users’ likeness recently became an interesting research topic. Such digital bodies show a great potential to enhance the authenticity of social VR citizens and increase the trustworthiness of interpersonal interaction. However, using such digital bodies might expose users to privacy and identity issues such as identity theft: For instance, how do we know whether the avatars we encounter in the virtual world are who they claim to be? Safeguarding users’ identities and privacy, and preventing harm from identity infringement, are crucial to the future of social VR. This article provides a systematic review on the protection of users’ identity and privacy in social VR, with a specific focus on digital bodies. Based on 814 sources, we identified and analyzed 49 papers that either: 1) discuss or raise concerns about the addressed issues, 2) provide technologies and potential solutions for protecting digital bodies, or 3) examine the relationship between the digital bodies and users of social VR citizens. We notice a severe lack of research and attention on the addressed topic and identify several research gaps that need to be filled. While some legal and ethical concerns about the potential identity issues of the digital bodies have been raised, and despite some progress in specific areas such as user authentication has been made, little research has proposed practical solutions. Finally, we suggest potential future research directions for digital body protection and include relevant research that might provide insights. We hope this work could provide a good overview of the existing discussion, potential solutions, and future directions for researchers with similar concerns. We also wish to draw attention to identity and privacy issues in social VR and call for interdisciplinary collaboration.}, author = {Lin, Jinghuai and Latoschik, Marc Erich}, journal = {Frontiers in Virtual Reality}, keywords = {prima}, title = {Digital body, identity and privacy in social virtual reality: A systematic review}, volume = 3, year = 2022 }
Obremski, D., Friedrich, P., Haak, N., Schaper, P., Lugrin, B.: The impact of mixed-cultural speech on the stereotypical perception of a virtual robot. Frontiers in Robotics and AI. 9, (2022).
- [ BibTeX ]
- [ URL ]
- [ DOI ]
@article{Obremski_2022, author = {Obremski, David and Friedrich, Paula and Haak, Nora and Schaper, Philipp and Lugrin, Birgit}, journal = {Frontiers in Robotics and AI}, keywords = {schaper}, month = {nov}, publisher = {Frontiers Media SA}, title = {The impact of mixed-cultural speech on the stereotypical perception of a virtual robot}, volume = 9, year = 2022 }
Obremski, D., Hering, H.B., Friedrich, P., Lugrin, B.: Exploratory Study on the Perception of Intelligent Virtual Agents With Non-Native Accents Using Synthetic and Natural Speech in German. INTERNATIONAL CONFERENCE ON MULTIMODAL INTERACTION. ACM (2022).
- [ BibTeX ]
- [ URL ]
- [ DOI ]
@inproceedings{Obremski_2022, author = {Obremski, David and Hering, Helena Babette and Friedrich, Paula and Lugrin, Birgit}, booktitle = {INTERNATIONAL CONFERENCE ON MULTIMODAL INTERACTION}, keywords = {obremski}, month = {nov}, publisher = {ACM}, title = {Exploratory Study on the Perception of Intelligent Virtual Agents With Non-Native Accents Using Synthetic and Natural Speech in German}, year = 2022 }
Kobs, K., Steininger, M., Hotho, A.: InDiReCT: Language-Guided Zero-Shot Deep Metric Learning for Images, http://arxiv.org/abs/2211.12760, (2022).
- [ Abstract ]
- [ BibTeX ]
- [ URL ]
Common Deep Metric Learning (DML) datasets specify only one notion of similarity, e.g., two images in the Cars196 dataset are deemed similar if they show the same car model. We argue that depending on the application, users of image retrieval systems have different and changing similarity notions that should be incorporated as easily as possible. Therefore, we present Language-Guided Zero-Shot Deep Metric Learning (LanZ-DML) as a new DML setting in which users control the properties that should be important for image representations without training data by only using natural language. To this end, we propose InDiReCT (Image representations using Dimensionality Reduction on CLIP embedded Texts), a model for LanZ-DML on images that exclusively uses a few text prompts for training. InDiReCT utilizes CLIP as a fixed feature extractor for images and texts and transfers the variation in text prompt embeddings to the image embedding space. Extensive experiments on five datasets and overall thirteen similarity notions show that, despite not seeing any images during training, InDiReCT performs better than strong baselines and approaches the performance of fully-supervised models. An analysis reveals that InDiReCT learns to focus on regions of the image that correlate with the desired similarity notion, which makes it a fast to train and easy to use method to create custom embedding spaces only using natural language.

@misc{kobs2022indirect, abstract = {Common Deep Metric Learning (DML) datasets specify only one notion of similarity, e.g., two images in the Cars196 dataset are deemed similar if they show the same car model. We argue that depending on the application, users of image retrieval systems have different and changing similarity notions that should be incorporated as easily as possible. Therefore, we present Language-Guided Zero-Shot Deep Metric Learning (LanZ-DML) as a new DML setting in which users control the properties that should be important for image representations without training data by only using natural language. To this end, we propose InDiReCT (Image representations using Dimensionality Reduction on CLIP embedded Texts), a model for LanZ-DML on images that exclusively uses a few text prompts for training. InDiReCT utilizes CLIP as a fixed feature extractor for images and texts and transfers the variation in text prompt embeddings to the image embedding space. Extensive experiments on five datasets and overall thirteen similarity notions show that, despite not seeing any images during training, InDiReCT performs better than strong baselines and approaches the performance of fully-supervised models. An analysis reveals that InDiReCT learns to focus on regions of the image that correlate with the desired similarity notion, which makes it a fast to train and easy to use method to create custom embedding spaces only using natural language.}, author = {Kobs, Konstantin and Steininger, Michael and Hotho, Andreas}, keywords = {zero}, note = {cite arxiv:2211.12760Comment: Accepted to WACV 2023}, title = {InDiReCT: Language-Guided Zero-Shot Deep Metric Learning for Images}, year = 2022 }
Loh, F., Mehling, N., Geißler, S., Hoßfeld, T.: Graph-Based Gateway Placement for Better Performance in LoRaWAN Deployments. 20th Mediterranean Communication and Computer Networking Conference (MedComNet) (2022).
- [ Abstract ]
- [ BibTeX ]
Low Power Wide Area Networks with Long Range Wide Area Networks (LoRaWANs) as one of their most prominent representatives are very promising solutions for future Internet of Things deployments. The technology is characterized by low energy requirements leading to long battery lifetimes. However, the drawback is very limited throughput rates. However, the unreliable nature of the LoRa technology is hindering the adoption. Especially its random channel access approach leads to significant message collisions and thus, data loss in larger deployments. From a network planning point of view, one possibility to deal with collisions is the reduction of potentially colliding messages at the frequency bands in combination with limiting the transmission duration of messages. For that reason, we present a novel graph-based gateway placement approach. The main focus is collision probability reduction, which directly increases reliability in LoRaWAN deployments. We show that our approach performs similar to state-of-the-art related work in the worst case and reduces the required number of gateways by up to 40% while reducing the collision probability by up to 70%. Furthermore, we discuss the scalability of our approach to cover arbitrarily large networks with gateways and only little overhead by splitting the problem into smaller sub-problems.

@inproceedings{info3-inproceedings-2022-19, abstract = {Low Power Wide Area Networks with Long Range Wide Area Networks (LoRaWANs) as one of their most prominent representatives are very promising solutions for future Internet of Things deployments. The technology is characterized by low energy requirements leading to long battery lifetimes. However, the drawback is very limited throughput rates. However, the unreliable nature of the LoRa technology is hindering the adoption. Especially its random channel access approach leads to significant message collisions and thus, data loss in larger deployments. From a network planning point of view, one possibility to deal with collisions is the reduction of potentially colliding messages at the frequency bands in combination with limiting the transmission duration of messages. For that reason, we present a novel graph-based gateway placement approach. The main focus is collision probability reduction, which directly increases reliability in LoRaWAN deployments. We show that our approach performs similar to state-of-the-art related work in the worst case and reduces the required number of gateways by up to 40% while reducing the collision probability by up to 70%. Furthermore, we discuss the scalability of our approach to cover arbitrarily large networks with gateways and only little overhead by splitting the problem into smaller sub-problems.}, author = {Loh, Frank and Mehling, Noah and Geißler, Stefan and Hoßfeld, Tobias}, booktitle = {20th Mediterranean Communication and Computer Networking Conference (MedComNet)}, keywords = {5mart}, month = 6, title = {Graph-Based Gateway Placement for Better Performance in LoRaWAN Deployments}, year = 2022 }
Loh, F., Geißler, S., Hoßfeld, T.: LoRaWAN Network Planning in Smart Environments: Towards Reliability, Scalability, and Cost Reduction. WueWoWAS 22 - KuVS Fachgespräch - Würzburg Workshop on Next-Generation Communication Networks (2022).
- [ Abstract ]
- [ BibTeX ]
The goal in this work is to present a guidance for LoRaWAN planning to improve overall reliability for message transmissions and scalability. At the end, the cost component is discussed. Therefore, a five step approach is presented that helps to plan a LoRaWAN deployment step by step: Based on the device locations, an initial gateway placement is suggested followed by in-depth frequency and channel access planning. After an initial planning phase, updates for channel access and the initial gateway planning is suggested that should also be done periodically during network operation. Since current gateway placement approaches are only studied with random channel access, there is a lot of potential in the cell planning phase. Furthermore, the performance of different channel access approaches is highly related on network load, and thus cell size and sensor density. Last, the influence of different cell planning ideas on expected costs are discussed.

@inproceedings{info3-inproceedings-2022-20, abstract = {The goal in this work is to present a guidance for LoRaWAN planning to improve overall reliability for message transmissions and scalability. At the end, the cost component is discussed. Therefore, a five step approach is presented that helps to plan a LoRaWAN deployment step by step: Based on the device locations, an initial gateway placement is suggested followed by in-depth frequency and channel access planning. After an initial planning phase, updates for channel access and the initial gateway planning is suggested that should also be done periodically during network operation. Since current gateway placement approaches are only studied with random channel access, there is a lot of potential in the cell planning phase. Furthermore, the performance of different channel access approaches is highly related on network load, and thus cell size and sensor density. Last, the influence of different cell planning ideas on expected costs are discussed.}, author = {Loh, Frank and Geißler, Stefan and Hoßfeld, Tobias}, booktitle = {WueWoWAS 22 - KuVS Fachgespräch - Würzburg Workshop on Next-Generation Communication Networks}, keywords = {5mart}, month = 7, title = {LoRaWAN Network Planning in Smart Environments: Towards Reliability, Scalability, and Cost Reduction}, year = 2022 }
Loh, F., Wamser, F., Poignée, F., Geißler, S., Hoßfeld, T.: YouTube Dataset on Mobile Streaming for Internet Traffic Modeling and Streaming Analysis. Nature, Scientific Data. (2022).
- [ Abstract ]
- [ BibTeX ]
Around 4.9 billion Internet users worldwide watch billions of hours of online video every day. As a result, streaming is by far the predominant type of traffic in communication networks. According to Google statistics, three out of five video views come from mobile devices. Thus, in view of the continuous technological advances in end devices and increasing mobile use, datasets for mobile streaming are indispensable in research but only sparsely dealt with in literature so far. With this public dataset, we provide 1,081 hours of time-synchronous video measurements at network, transport, and application layer with the native YouTube streaming client on mobile devices. The dataset includes 80 network scenarios with 171 different individual bandwidth settings measured in 5,181 runs with limited bandwidth, 1,939 runs with emulated 3 G/4 G traces, and 4,022 runs with pre-defined bandwidth changes. This corresponds to 332 GB video payload. We present the most relevant quality indicators for scientific use, i.e., initial playback delay, streaming video quality, adaptive video quality changes, video rebuffering events, and streaming phases.

@article{info3-article-2022-17, abstract = {Around 4.9 billion Internet users worldwide watch billions of hours of online video every day. As a result, streaming is by far the predominant type of traffic in communication networks. According to Google statistics, three out of five video views come from mobile devices. Thus, in view of the continuous technological advances in end devices and increasing mobile use, datasets for mobile streaming are indispensable in research but only sparsely dealt with in literature so far. With this public dataset, we provide 1,081 hours of time-synchronous video measurements at network, transport, and application layer with the native YouTube streaming client on mobile devices. The dataset includes 80 network scenarios with 171 different individual bandwidth settings measured in 5,181 runs with limited bandwidth, 1,939 runs with emulated 3 G/4 G traces, and 4,022 runs with pre-defined bandwidth changes. This corresponds to 332 GB video payload. We present the most relevant quality indicators for scientific use, i.e., initial playback delay, streaming video quality, adaptive video quality changes, video rebuffering events, and streaming phases.}, author = {Loh, Frank and Wamser, Florian and Poignée, Fabian and Geißler, Stefan and Hoßfeld, Tobias}, journal = {Nature, Scientific Data}, keywords = {huawei}, month = 6, title = {YouTube Dataset on Mobile Streaming for Internet Traffic Modeling and Streaming Analysis}, year = 2022 }
Lesch, V., Hadry, M., Kounev, S., Krupitzer, C.: Self-Aware Optimization of Adaptation Planning Strategies. ACM Transactions on Autonomous and Adaptive Systems. (2022).
- [ Abstract ]
- [ BibTeX ]
- [ URL ]
In today’s world, circumstances, processes, and requirements for software systems are becoming increasingly complex. In order to operate properly in such dynamic environments, software systems must adapt to these changes, which has led to the research area of Self-Adaptive Systems (SAS). Platooning is one example of adaptive systems in Intelligent Transportation Systems, which is the ability of vehicles to travel with close inter-vehicle distances. This technology leads to an increase in road throughput and safety, which directly addresses the increased infrastructure needs due to increased traffic on the roads. However, the No-Free-Lunch theorem states that the performance of one adaptation planning strategy is not necessarily transferable to other problems. Moreover, especially in the field of SAS, the selection of the most appropriate strategy depends on the current situation of the system. In this paper, we address the problem of self-aware optimization of adaptation planning strategies by designing a framework that includes situation detection, strategy selection, and parameter optimization of the selected strategies. We apply our approach on the case study platooning coordination and evaluate the performance of the proposed framework.

@article{lesch2022selfaware, abstract = {In today’s world, circumstances, processes, and requirements for software systems are becoming increasingly complex. In order to operate properly in such dynamic environments, software systems must adapt to these changes, which has led to the research area of Self-Adaptive Systems (SAS). Platooning is one example of adaptive systems in Intelligent Transportation Systems, which is the ability of vehicles to travel with close inter-vehicle distances. This technology leads to an increase in road throughput and safety, which directly addresses the increased infrastructure needs due to increased traffic on the roads. However, the No-Free-Lunch theorem states that the performance of one adaptation planning strategy is not necessarily transferable to other problems. Moreover, especially in the field of SAS, the selection of the most appropriate strategy depends on the current situation of the system. In this paper, we address the problem of self-aware optimization of adaptation planning strategies by designing a framework that includes situation detection, strategy selection, and parameter optimization of the selected strategies. We apply our approach on the case study platooning coordination and evaluate the performance of the proposed framework.}, author = {Lesch, Veronika and Hadry, Marius and Kounev, Samuel and Krupitzer, Christian}, journal = {ACM Transactions on Autonomous and Adaptive Systems}, keywords = {myown}, month = {oct}, title = {Self-Aware Optimization of Adaptation Planning Strategies}, year = 2022 }
Firman, O., Kindermann, P., Klawitter, J., Klemz, B., Klesen, F., Wolff, A.: Outside-Obstacle Representations with All Vertices on the Outer Face. In: {Di Giacomo}, E. und Montecchiani, F. (hrsg.) Proc. 38th Europ. Workshop Comput. Geom. (EuroCG’22). S. 54:1–8 (2022).
- [ BibTeX ]
@inproceedings{fkkkkw-ooravof-EuroCG22, author = {Firman, Oksana and Kindermann, Philipp and Klawitter, Jonathan and Klemz, Boris and Klesen, Felix and Wolff, Alexander}, booktitle = {Proc. 38th Europ. Workshop Comput. Geom. (EuroCG'22)}, editor = {{Di Giacomo}, Emilio and Montecchiani, Fabrizio}, keywords = {myown}, pages = {54:1–8}, title = {Outside-Obstacle Representations with All Vertices on the Outer Face}, year = 2022 }
Casas, P., Wehner, N., Wassermann, S., Seufert, M.: Fingerprinting Webpages and Smartphone Apps from Encrypted Network Traffic with WebScanner. Global Internet (GI) Symposium. , Paris, France (2022).
- [ Abstract ]
- [ BibTeX ]
The wide adoption of end-to-end encryption drastically limits the visibility Internet Service Providers (ISPs) have on the services consumed by their customers. This is particularly challenging for monitoring and analysis of web and apps traffic, which is highly complex and heterogeneous. Loading a web page or app today requires tens of flows to download the various resources located in distributed cloud servers from different content providers. We introduce WebScanner, a webpage and app fingerprinting approach capable to identify all the traffic flows corresponding to individual webpage and app loading sessions within concurrent web pages traffic, enabling highly detailed, per webpage analysis in practical deployments. Different from the state of the art in web and app traffic fingerprinting, and as our most relevant contribution, WebScanner automatically performs the parsing of all the traffic generated by a web visit and its isolation from concurrent traffic, instead of assuming that an external oracle system does so. WebScanner also implements a deep fingerprinting approach to detect user action-dependent traffic from apps, relying on simple machine learning models and strong input features as fingerprints. Extensive evaluation across a large measurement dataset of popular webpages and mobile apps confirms the outstanding performance of WebScanner, identifying the top-500 Alexa websites with precision and recall (P/R) above 95%, isolating their full contents with P/R above 80% for up to 15 concurrent webpages, and detecting specific action-dependent apps traffic with average P/R above 92%.

@inproceedings{info3-inproceedings-2022-18, abstract = {The wide adoption of end-to-end encryption drastically limits the visibility Internet Service Providers (ISPs) have on the services consumed by their customers. This is particularly challenging for monitoring and analysis of web and apps traffic, which is highly complex and heterogeneous. Loading a web page or app today requires tens of flows to download the various resources located in distributed cloud servers from different content providers. We introduce WebScanner, a webpage and app fingerprinting approach capable to identify all the traffic flows corresponding to individual webpage and app loading sessions within concurrent web pages traffic, enabling highly detailed, per webpage analysis in practical deployments. Different from the state of the art in web and app traffic fingerprinting, and as our most relevant contribution, WebScanner automatically performs the parsing of all the traffic generated by a web visit and its isolation from concurrent traffic, instead of assuming that an external oracle system does so. WebScanner also implements a deep fingerprinting approach to detect user action-dependent traffic from apps, relying on simple machine learning models and strong input features as fingerprints. Extensive evaluation across a large measurement dataset of popular webpages and mobile apps confirms the outstanding performance of WebScanner, identifying the top-500 Alexa websites with precision and recall (P/R) above 95%, isolating their full contents with P/R above 80% for up to 15 concurrent webpages, and detecting specific action-dependent apps traffic with average P/R above 92%.}, address = {Paris, France}, author = {Casas, Pedro and Wehner, Nikolas and Wassermann, Sarah and Seufert, Michael}, booktitle = {Global Internet (GI) Symposium}, keywords = {ucn}, month = 11, title = {Fingerprinting Webpages and Smartphone Apps from Encrypted Network Traffic with WebScanner}, year = 2022 }
Klawitter, J., Klesen, F., Wolff, A.: Algorithms for Floor Planning with Proximity Requirements. In: Gerber, D.J., Nahmad, A., Bogosian, B., Pantazis, E., und Miltiadis, C. (hrsg.) Proc. CAAD Future 2021. S. 151–171. Springer-Verlag (2022).
- [ BibTeX ]
- [ DOI ]
@inproceedings{kkw-afppr-CAADF21, author = {Klawitter, Jonathan and Klesen, Felix and Wolff, Alexander}, booktitle = {Proc. CAAD Future 2021}, editor = {Gerber, David J. and Nahmad, Alicia and Bogosian, Biayna and Pantazis, Evan and Miltiadis, Constantinos}, keywords = {myown}, pages = {151–171}, publisher = {Springer-Verlag}, series = {CCIS}, title = {Algorithms for Floor Planning with Proximity Requirements}, volume = 1465, year = 2022 }
Schell, C., Hotho, A., Latoschik, M.E.: Comparison of Data Representations and Machine Learning Architectures for User Identification on Arbitrary Motion Sequences. Proceedings of the IEEE International conference on artificial intelligence & Virtual Reality (IEEE AIVR). IEEE (2022).
- [ BibTeX ]
@inproceedings{schell2022comparison, author = {Schell, Christian and Hotho, Andreas and Latoschik, Marc Erich}, booktitle = {Proceedings of the IEEE International conference on artificial intelligence & Virtual Reality (IEEE AIVR)}, keywords = {myown}, note = {to appear}, publisher = {IEEE}, title = {Comparison of Data Representations and Machine Learning Architectures for User Identification on Arbitrary Motion Sequences}, year = 2022 }
Latoschik, M.E., Wienrich, C.: Congruence and Plausibility, not Presence?! Pivotal Conditions for XR Experiences and Effects, a Novel Model. Frontiers in Virtual Reality. 3, (2022).
- [ Abstract ]
- [ BibTeX ]
- [ URL ]
- [ DOI ]
Presence is often considered the most important quale describing the subjective feeling of being in a computer-generated and/or computer-mediated virtual environment. The identification and separation of orthogonal presence components, i.e., the place illusion and the plausibility illusion, has been an accepted theoretical model describing Virtual Reality (VR) experiences for some time. This perspective article challenges this presence-oriented VR theory. First, we argue that a place illusion cannot be the major construct to describe the much wider scope of virtual, augmented, and mixed reality (VR, AR, MR: or XR for short). Second, we argue that there is no plausibility illusion but merely plausibility, and we derive the place illusion caused by the congruent and plausible generation of spatial cues and similarly for all the current model’s so-defined illusions. Finally, we propose congruence and plausibility to become the central essential conditions in a novel theoretical model describing XR experiences and effects.

@article{latoschik2021coherence, abstract = {Presence is often considered the most important quale describing the subjective feeling of being in a computer-generated and/or computer-mediated virtual environment. The identification and separation of orthogonal presence components, i.e., the place illusion and the plausibility illusion, has been an accepted theoretical model describing Virtual Reality (VR) experiences for some time. This perspective article challenges this presence-oriented VR theory. First, we argue that a place illusion cannot be the major construct to describe the much wider scope of virtual, augmented, and mixed reality (VR, AR, MR: or XR for short). Second, we argue that there is no plausibility illusion but merely plausibility, and we derive the place illusion caused by the congruent and plausible generation of spatial cues and similarly for all the current model’s so-defined illusions. Finally, we propose congruence and plausibility to become the central essential conditions in a novel theoretical model describing XR experiences and effects.}, author = {Latoschik, Marc Erich and Wienrich, Carolin}, journal = {Frontiers in Virtual Reality}, keywords = {myown}, month = {jun}, title = {Congruence and Plausibility, not Presence?! Pivotal Conditions for XR Experiences and Effects, a Novel Model}, volume = 3, year = 2022 }
Schaper, P., Riedmann, A., Oberdörfer, S., Lugrin, B.: Addressing Waste Separation With a Persuasive Augmented Reality App. Proceedings of the 24th International Conference on Mobile Human-Computer Interaction (MobileHCI ’22). Association for Computing Machinery, New York, NY, USA (2022).
- [ BibTeX ]
- [ DOI ]
@inproceedings{schaper2022addressing, address = {New York, NY, USA}, author = {Schaper, Philipp and Riedmann, Anna and Oberdörfer, Sebastian and Lugrin, Birgit}, booktitle = {Proceedings of the 24th International Conference on Mobile Human-Computer Interaction (MobileHCI '22)}, keywords = {schaper}, publisher = {Association for Computing Machinery}, title = {Addressing Waste Separation With a Persuasive Augmented Reality App}, year = 2022 }
Steinhaeusser, S.C., Riedmann, A., Schaper, P., Guthmann, E., Pfister, J., Schmitt, K., Wild, T., Lugrin, B.: Second Language Learning through Storytelling with a Social Robot-An Online Case Study. 2022 31st IEEE International Conference on Robot and Human Interactive Communication (RO-MAN). S. 67–74. IEEE (2022).
- [ BibTeX ]
@inproceedings{steinhaeusser2022second, author = {Steinhaeusser, Sophia C. and Riedmann, Anna and Schaper, Philipp and Guthmann, Emily and Pfister, Julia and Schmitt, Katharina and Wild, Theresa and Lugrin, Birgit}, booktitle = {2022 31st IEEE International Conference on Robot and Human Interactive Communication (RO-MAN)}, keywords = {storytelling}, organization = {IEEE}, pages = {67-74}, title = {Second Language Learning through Storytelling with a Social Robot-An Online Case Study}, year = 2022 }
Steinhaeusser, S.C., Lein, M., Donnermann, M., Lugrin, B.: Designing Social Robots’ Speech in the Hotel Context-A Series of Online Studies. 2022 31st IEEE International Conference on Robot and Human Interactive Communication (RO-MAN). S. 163–170. IEEE (2022).
- [ BibTeX ]
@inproceedings{steinhaeusser2022designing, author = {Steinhaeusser, Sophia C. and Lein, Martina and Donnermann, Melissa and Lugrin, Birgit}, booktitle = {2022 31st IEEE International Conference on Robot and Human Interactive Communication (RO-MAN)}, keywords = {storyteller}, organization = {IEEE}, pages = {163-170}, title = {Designing Social Robots' Speech in the Hotel Context-A Series of Online Studies}, year = 2022 }
Donnermann, M., Schaper, P., Lugrin, B.: Investigating Adaptive Robot Tutoring in a Long-Term Interaction in Higher Education. 31st IEEE International Conference on Robot and Human Interactive Communication (RO-MAN 2022). S. 171–178. IEEE (2022).
- [ BibTeX ]
@inproceedings{donnermann2022investigating, author = {Donnermann, Melissa and Schaper, Philipp and Lugrin, Birgit}, booktitle = {31st IEEE International Conference on Robot and Human Interactive Communication (RO-MAN 2022)}, keywords = {schaper}, organization = {IEEE}, pages = {171-178}, title = {Investigating Adaptive Robot Tutoring in a Long-Term Interaction in Higher Education}, year = 2022 }
Geißler, S., Lange, S., Haßllinger, G., Tran-Gia, P., Hoßfeld, T.: Discrete-Time Analysis of Multi-Component Queuing Networks under Renewal Approximation. 34st International Teletraffic Congress (ITC). , Shenzhen, China (2022).
- [ Abstract ]
- [ BibTeX ]
The analytical and numerical performance evaluation of network components and distributed systems has been a staple in the networking community for many years. However, the ever growing complexity of modern systems and the need to gain detailed insights into systems consisting of many, interconnected components emphasizes the need for an extension to the classical single-component approach, and although approaches like Jackson Networks exist, their limited application scope lags behind the complexity of modern environments. To this end, we revisit existing models of the common Gi/Gi/1-oo queue, extend them to allow the concatenation of multiple queueing components, and evaluate the approximation error introduced through renewal approximation. We revisit previously performed parameter studies and evaluate the approximation error for a wide range of parameter combinations that we can solve through the power of modern computing equipment and efficient numerical implementations of our models. We show the main impact factors for the linear concatenation of queueing components as well as the split and superposition of processes. Our evaluations show that the renewal approximation can be applied to a wide range of parameters while still obtaining results within acceptable error margins.

@inproceedings{info3-inproceedings-2022-17, abstract = {The analytical and numerical performance evaluation of network components and distributed systems has been a staple in the networking community for many years. However, the ever growing complexity of modern systems and the need to gain detailed insights into systems consisting of many, interconnected components emphasizes the need for an extension to the classical single-component approach, and although approaches like Jackson Networks exist, their limited application scope lags behind the complexity of modern environments. To this end, we revisit existing models of the common Gi/Gi/1-oo queue, extend them to allow the concatenation of multiple queueing components, and evaluate the approximation error introduced through renewal approximation. We revisit previously performed parameter studies and evaluate the approximation error for a wide range of parameter combinations that we can solve through the power of modern computing equipment and efficient numerical implementations of our models. We show the main impact factors for the linear concatenation of queueing components as well as the split and superposition of processes. Our evaluations show that the renewal approximation can be applied to a wide range of parameters while still obtaining results within acceptable error margins.}, author = {Geißler, Stefan and Lange, Stanislav and Haßllinger, Gerhard and Tran-Gia, Phuoc and Hoßfeld, Tobias}, booktitle = {34st International Teletraffic Congress (ITC). , Shenzhen, China}, keywords = {can}, month = 9, title = {Discrete-Time Analysis of Multi-Component Queuing Networks under Renewal Approximation}, year = 2022 }
Heß, J., Karageorgos, P., Richter, T., Müller, B., Riedmann, A., Schaper, P., Lugrin, B.: Digitale Leseförderung: Effekte eines silbenbasierten digitalen Lesetrainings in Klasse 2. Vortrag auf dem 52. Kongress der Deutschen Gesellschaft für Psychologie (DGPs) (2022).
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@conference{hess2022digitale, author = {Heß, J. and Karageorgos, P. and Richter, T. and Müller, B. and Riedmann, A. and Schaper, P. and Lugrin, B.}, booktitle = {Vortrag auf dem 52. Kongress der Deutschen Gesellschaft für Psychologie (DGPs)}, keywords = {schaper}, title = {Digitale Leseförderung: Effekte eines silbenbasierten digitalen Lesetrainings in Klasse 2}, year = 2022 }
Hein, R., Latoschik, M.E., Wienrich, C.: Usability and User Experience of Virtual Objects Supporting Learning and Communicating in Virtual Reality. In: Pfleging, B., Gerling, K., und Mayer, S. (hrsg.) Mensch und Computer 2022 - Tagungsband. S. 510–514. ACM, New York (2022).
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This study aims to evaluate the usability and user experience of the InteractionSuitecase. This is a collection of virtual objects that have cultural connotations (associated with German or Anglo-American culture). They are intended to promote communication about cultural differences and similarities in English lessons at German schools. They are thus part of a didactic concept for using social VR for trans- and intercultural learning. Future teacher used the virtual objects during a practical seminar and rated them as useful. Further they associates a positive user experience. Since the virtual objects should encourage communication, the sense of connectedness instead of isolation is a very important results. The results proved the readiness of the InteractionSuitcase for further pedagogical applications.

@inproceedings{mci/Hein2022, abstract = {This study aims to evaluate the usability and user experience of the InteractionSuitecase. This is a collection of virtual objects that have cultural connotations (associated with German or Anglo-American culture). They are intended to promote communication about cultural differences and similarities in English lessons at German schools. They are thus part of a didactic concept for using social VR for trans- and intercultural learning. Future teacher used the virtual objects during a practical seminar and rated them as useful. Further they associates a positive user experience. Since the virtual objects should encourage communication, the sense of connectedness instead of isolation is a very important results. The results proved the readiness of the InteractionSuitcase for further pedagogical applications.}, address = {New York}, author = {Hein, Rebecca and Latoschik, Marc Erich and Wienrich, Carolin}, booktitle = {Mensch und Computer 2022 - Tagungsband}, editor = {Pfleging, Bastian and Gerling, Kathrin and Mayer, Sven}, keywords = {rhein}, pages = {510-514}, publisher = {ACM}, title = {Usability and User Experience of Virtual Objects Supporting Learning and Communicating in Virtual Reality}, year = 2022 }
Keller, S., Hoßfeld, T., von Mammen, S.: Edge-Case Integration into Established NAT Traversal Techniques. 2022 IEEE Ninth International Conference on Communications and Electronics (ICCE). S. 75–80 (2022).
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Traversing Network Address Translation (NAT) is often necessary for establishing direct communication between clients. The traversal of NAT with static port translation is solved in many cases by the Session Traversal Utilities for NAT (STUN) protocol. Nevertheless, it does not cover the traversal of progressing symmetric and random symmetric NAT, which make it necessary to correctly predict opened ports. This paper presents a method for predicting (a) progressing symmetric NAT-translated ports based on a network traffic model and the Expected Value Method, and (b) random symmetric NAT-translated ports based on heuristics between monitored and opened ports across numerous traversal attempts. Tests were conducted in German cities using local cellular communication providers. Compared to established approaches, they yielded considerable improvements traversing progressing symmetric NAT and slight improvements traversing random symmetric NAT in real-world environments.

@inproceedings{9852092, abstract = {Traversing Network Address Translation (NAT) is often necessary for establishing direct communication between clients. The traversal of NAT with static port translation is solved in many cases by the Session Traversal Utilities for NAT (STUN) protocol. Nevertheless, it does not cover the traversal of progressing symmetric and random symmetric NAT, which make it necessary to correctly predict opened ports. This paper presents a method for predicting (a) progressing symmetric NAT-translated ports based on a network traffic model and the Expected Value Method, and (b) random symmetric NAT-translated ports based on heuristics between monitored and opened ports across numerous traversal attempts. Tests were conducted in German cities using local cellular communication providers. Compared to established approaches, they yielded considerable improvements traversing progressing symmetric NAT and slight improvements traversing random symmetric NAT in real-world environments.}, author = {Keller, Simon and Hoßfeld, Tobias and von Mammen, Sebastian}, booktitle = {2022 IEEE Ninth International Conference on Communications and Electronics (ICCE)}, keywords = {myown}, month = {July}, pages = {75-80}, title = {Edge-Case Integration into Established NAT Traversal Techniques}, year = 2022 }
Wolf, E., Mal, D., Frohnapfel, V., Döllinger, N., Wenninger, S., Botsch, M., Latoschik, M.E., Wienrich, C.: Plausibility and Perception of Personalized Virtual Humans between Virtual and Augmented Reality. 2022 IEEE International Symposium on Mixed and Augmented Reality (ISMAR). S. 489–498 (2022).
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This article investigates the effects of different XR displays on the perception and plausibility of personalized virtual humans. We compared immersive virtual reality (VR), video see-through augmented reality (VST AR), and optical see-through AR (OST AR). The personalized virtual alter egos were generated by state-of-the-art photogrammetry methods. 42 participants were repeatedly exposed to animated versions of their 3D-reconstructed virtual alter egos in each of the three XR display conditions. The reconstructed virtual alter egos were additionally modified in body weight for each repetition. We show that the display types lead to different degrees of incongruence between the renderings of the virtual humans and the presentation of the respective environmental backgrounds, leading to significant effects of perceived mismatches as part of a plausibility measurement. The device-related effects were further partly confirmed by subjective misestimations of the modified body weight and the measured spatial presence. Here, the exceedingly incongruent OST AR condition leads to the significantly highest weight misestimations as well as to the lowest perceived spatial presence. However, similar effects could not be confirmed for the affective appraisal (i.e., humanness, eeriness, or attractiveness) of the virtual humans, giving rise to the assumption that these factors might be unrelated to each other.

@inproceedings{wolf2022plausibility, abstract = {This article investigates the effects of different XR displays on the perception and plausibility of personalized virtual humans. We compared immersive virtual reality (VR), video see-through augmented reality (VST AR), and optical see-through AR (OST AR). The personalized virtual alter egos were generated by state-of-the-art photogrammetry methods. 42 participants were repeatedly exposed to animated versions of their 3D-reconstructed virtual alter egos in each of the three XR display conditions. The reconstructed virtual alter egos were additionally modified in body weight for each repetition. We show that the display types lead to different degrees of incongruence between the renderings of the virtual humans and the presentation of the respective environmental backgrounds, leading to significant effects of perceived mismatches as part of a plausibility measurement. The device-related effects were further partly confirmed by subjective misestimations of the modified body weight and the measured spatial presence. Here, the exceedingly incongruent OST AR condition leads to the significantly highest weight misestimations as well as to the lowest perceived spatial presence. However, similar effects could not be confirmed for the affective appraisal (i.e., humanness, eeriness, or attractiveness) of the virtual humans, giving rise to the assumption that these factors might be unrelated to each other.}, author = {Wolf, Erik and Mal, David and Frohnapfel, Viktor and Döllinger, Nina and Wenninger, Stephan and Botsch, Mario and Latoschik, Marc Erich and Wienrich, Carolin}, booktitle = {2022 IEEE International Symposium on Mixed and Augmented Reality (ISMAR)}, keywords = {vitras}, pages = {489-498}, title = {Plausibility and Perception of Personalized Virtual Humans between Virtual and Augmented Reality}, year = 2022 }
Gemesi, K., Holzmann, S.L., Hochrein, R., D{\"o}llinger, N., Wienrich, C., Weinberger, N.-A., Luck-Sikorski, C., Holzapfel, C.: Attitude of Nutrition Experts Toward Psychotherapy and Virtual Reality as Part of Obesity Treatment—An Online Survey. Frontiers in Psychiatry. 13, (2022).
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@article{gemesi2022attitude, author = {Gemesi, Kathrin and Holzmann, Sophie Laura and Hochrein, Regine and D{\"o}llinger, Nina and Wienrich, Carolin and Weinberger, Natascha-Alexandra and Luck-Sikorski, Claudia and Holzapfel, Christina}, journal = {Frontiers in Psychiatry}, keywords = {vitras}, publisher = {Frontiers Media SA}, title = {Attitude of Nutrition Experts Toward Psychotherapy and Virtual Reality as Part of Obesity Treatment—An Online Survey}, volume = 13, year = 2022 }
Kindermann, P., Sauer, J., Wolff, A.: The Computational Complexity of the {ChordLink} Model. In: {Di Giacomo}, E. und Montecchiani, F. (hrsg.) Proc. 38th Europ. Workshop Comput. Geom. (EuroCG’22). S. 10:1–7 (2022).
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@inproceedings{ksw-cccm-EuroCG22, author = {Kindermann, Philipp and Sauer, Jan and Wolff, Alexander}, booktitle = {Proc. 38th Europ. Workshop Comput. Geom. (EuroCG'22)}, editor = {{Di Giacomo}, Emilio and Montecchiani, Fabrizio}, keywords = {myown}, pages = {10:1–7}, title = {The Computational Complexity of the {ChordLink} Model}, year = 2022 }
Steinhaeusser, S.C., Lugrin, B.: Effects of Colored LEDs in Robotic Storytelling on Storytelling Experience and Robot Perception. Proceedings of the 2022 ACM/IEEE International Conference on Human-Robot Interaction (HRI2022). IEEE Press (2022).
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@inproceedings{steinhaeusser2022effects, author = {Steinhaeusser, Sophia C. and Lugrin, Birgit}, booktitle = {Proceedings of the 2022 ACM/IEEE International Conference on Human-Robot Interaction (HRI2022)}, keywords = {storyteller}, publisher = {IEEE Press}, title = {Effects of Colored LEDs in Robotic Storytelling on Storytelling Experience and Robot Perception}, year = 2022 }
Wehner, N., Ring, M., Schüler, J., Hotho, A., Hoßfeld, T., Seufert, M.: On Learning Hierarchical Embeddings from Encrypted Network Traffic. 33th IEEE/IFIP Network Operations and Management Symposium (NOMS). , Budapest, Hungary (2022).
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This work presents a novel concept for learning embeddings from encrypted network traffic. In contrast to existing approaches, we evaluate the feasibility of hierarchical embeddings by iteratively aggregating packet embeddings to flow embeddings, and flow embeddings to trace embeddings. The hierarchical embedding concept was designed to especially consider complex dependencies of Internet traffic on different time scales. We describe this novel embedding concept for the domain of network traffic in full detail, and evaluate its performance for the downstream task of website fingerprinting, i.e., identifying websites from encrypted traffic, which is relevant for network management, e.g., as a prerequisite for QoE monitoring or for intrusion detection. Our evaluation reveals that embeddings are a promising solution for website fingerprinting as our model correctly labels up to 99.8\% of traces from 500 target websites.

@inproceedings{info3-inproceedings-2022-1, abstract = {This work presents a novel concept for learning embeddings from encrypted network traffic. In contrast to existing approaches, we evaluate the feasibility of hierarchical embeddings by iteratively aggregating packet embeddings to flow embeddings, and flow embeddings to trace embeddings. The hierarchical embedding concept was designed to especially consider complex dependencies of Internet traffic on different time scales. We describe this novel embedding concept for the domain of network traffic in full detail, and evaluate its performance for the downstream task of website fingerprinting, i.e., identifying websites from encrypted traffic, which is relevant for network management, e.g., as a prerequisite for QoE monitoring or for intrusion detection. Our evaluation reveals that embeddings are a promising solution for website fingerprinting as our model correctly labels up to 99.8\% of traces from 500 target websites.}, address = {Budapest, Hungary}, author = {Wehner, Nikolas and Ring, Markus and Schüler, Joshua and Hotho, Andreas and Hoßfeld, Tobias and Seufert, Michael}, booktitle = {33th IEEE/IFIP Network Operations and Management Symposium (NOMS)}, keywords = {myown}, month = 4, title = {On Learning Hierarchical Embeddings from Encrypted Network Traffic}, year = 2022 }
Zink, J., Walter, J., Baumeister, J., Wolff, A.: Layered Drawing of Undirected Graphs with Generalized Port Constraints. Computational Geometry: Theory and Applications. 105--106, 1–29 (2022).
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The aim of this research is a practical method to draw cable plans of complex machines. Such plans consist of electronic components and cables connecting specific ports of the components. Since the machines are configured for each client individually, cable plans need to be drawn automatically. The drawings must be well readable so that technicians can use them to debug the machines. In order to model plug sockets, we introduce port groups; within a group, ports can change their position (which we use to improve the aesthetics of the layout), but together the ports of a group must form a contiguous block. \par We approach the problem of drawing such cable plans by extending the well-known Sugiyama framework such that it incorporates ports and port groups. Since the framework assumes directed graphs, we propose several ways to orient the edges of the given undirected graph. We compare these methods experimentally, both on real-world data and synthetic data that carefully simulates real-world data. We measure the aesthetics of the resulting drawings by counting bends and crossings. Using these metrics, we experimentally compare our approach to Kieler [JVLC 2014], a library for drawing graphs in the presence of port constraints. Our method produced 10--30 \% fewer crossings, while it performed equally well or slightly worse than Kieler with respect to the number of bends and the time used to compute a drawing.

@article{zwbw-ldugg-CGTA22, abstract = {The aim of this research is a practical method to draw cable plans of complex machines. Such plans consist of electronic components and cables connecting specific ports of the components. Since the machines are configured for each client individually, cable plans need to be drawn automatically. The drawings must be well readable so that technicians can use them to debug the machines. In order to model plug sockets, we introduce port groups; within a group, ports can change their position (which we use to improve the aesthetics of the layout), but together the ports of a group must form a contiguous block. \par We approach the problem of drawing such cable plans by extending the well-known Sugiyama framework such that it incorporates ports and port groups. Since the framework assumes directed graphs, we propose several ways to orient the edges of the given undirected graph. We compare these methods experimentally, both on real-world data and synthetic data that carefully simulates real-world data. We measure the aesthetics of the resulting drawings by counting bends and crossings. Using these metrics, we experimentally compare our approach to Kieler [JVLC 2014], a library for drawing graphs in the presence of port constraints. Our method produced 10–30 \% fewer crossings, while it performed equally well or slightly worse than Kieler with respect to the number of bends and the time used to compute a drawing.}, author = {Zink, Johannes and Walter, Julian and Baumeister, Joachim and Wolff, Alexander}, journal = {Computational Geometry: Theory and Applications}, keywords = {port_constraints}, number = 101886, pages = {1–29}, title = {Layered Drawing of Undirected Graphs with Generalized Port Constraints}, volume = {105–106}, year = 2022 }
Wangsadirdja, D., Heinickel, F., Trapp, S., Zehe, A., Kobs, K., Hotho, A.: {W}ue{D}evils at {S}em{E}val-2022 Task 8: Multilingual News Article Similarity via Pair-Wise Sentence Similarity Matrices. Proceedings of the 16th International Workshop on Semantic Evaluation (SemEval-2022). S. 1235–1243. Association for Computational Linguistics, Seattle, United States (2022).
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We present a system that creates pair-wise cosine and arccosine sentence similarity matrices using multilingual sentence embeddings obtained from pre-trained SBERT and Universal Sentence Encoder (USE) models respectively. For each news article sentence, it searches the most similar sentence from the other article and computes an average score. Further, a convolutional neural network calculates a total similarity score for the article pairs on these matrices. Finally, a random forest regressor merges the previous results to a final score that can optionally be extended with a publishing date score.

@inproceedings{wangsadirdja2022wuedevils, abstract = {We present a system that creates pair-wise cosine and arccosine sentence similarity matrices using multilingual sentence embeddings obtained from pre-trained SBERT and Universal Sentence Encoder (USE) models respectively. For each news article sentence, it searches the most similar sentence from the other article and computes an average score. Further, a convolutional neural network calculates a total similarity score for the article pairs on these matrices. Finally, a random forest regressor merges the previous results to a final score that can optionally be extended with a publishing date score.}, address = {Seattle, United States}, author = {Wangsadirdja, Dirk and Heinickel, Felix and Trapp, Simon and Zehe, Albin and Kobs, Konstantin and Hotho, Andreas}, booktitle = {Proceedings of the 16th International Workshop on Semantic Evaluation (SemEval-2022)}, keywords = {similarity}, month = {jul}, pages = {1235–1243}, publisher = {Association for Computational Linguistics}, title = {{W}ue{D}evils at {S}em{E}val-2022 Task 8: Multilingual News Article Similarity via Pair-Wise Sentence Similarity Matrices}, year = 2022 }
Goe{\ss}mann, I., Klawitter, J., Klemz, B., Klesen, F., Kobourov, S.G., Kryven, M., Wolff, A., Zink, J.: The Segment Number: Algorithms and Universal Lower Bounds for Some Classes of Planar Graphs. In: Bekos, M. und Kaufmann, M. (hrsg.) Proc. 48th Int. Workshop Graph-Theoretic Concepts Comput. Sci. (WG’22). S. 16 pages. Springer-Verlag (2022).
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@inproceedings{gkkkkkwz-snaul-WG22, author = {Goe{\ss}mann, Ina and Klawitter, Jonathan and Klemz, Boris and Klesen, Felix and Kobourov, Stephen G. and Kryven, Myroslav and Wolff, Alexander and Zink, Johannes}, booktitle = {Proc. 48th Int. Workshop Graph-Theoretic Concepts Comput. Sci. (WG'22)}, editor = {Bekos, Michael and Kaufmann, Michael}, keywords = {visual_complexity}, pages = {16 pages}, publisher = {Springer-Verlag}, series = {Lecture Notes in Computer Science}, title = {The Segment Number: Algorithms and Universal Lower Bounds for Some Classes of Planar Graphs}, volume = 13453, year = 2022 }
Loh, F., Raffeck, S., Geißler, S., Hoßfeld, T.: Generic Model to Quantify Energy Consumption for Different LoRaWAN Channel Access Methods. 18th International Conference on Wireless and Mobile Computing, Networking and Communications (WiMob) (2022).
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LoRaWAN is one of the most promising Internet of Things technologies with regard to low energy consumption. However, the currently used random channel access has much potential for improvement. Thus, current literature studies alternative channel access approaches, but the energy consumption is often not taken into consideration. For that reason, we present a generic model to quantify energy consumption in LoRaWAN for different channel access mechanisms based on a state machine. With our model, we can describe the energy consumption for specific access mechanisms or for the complete network. Our model shows that random access only performs best if no additional receive windows are opened. A simple improvement is Listen before Talk. For networks with high load, improvements are achieved by a more complex scheduled MAC. Our model serves as a basis for future energy consumption studies, conducted through measurements or simulations.

@inproceedings{info3-inproceedings-2022-21, abstract = {LoRaWAN is one of the most promising Internet of Things technologies with regard to low energy consumption. However, the currently used random channel access has much potential for improvement. Thus, current literature studies alternative channel access approaches, but the energy consumption is often not taken into consideration. For that reason, we present a generic model to quantify energy consumption in LoRaWAN for different channel access mechanisms based on a state machine. With our model, we can describe the energy consumption for specific access mechanisms or for the complete network. Our model shows that random access only performs best if no additional receive windows are opened. A simple improvement is Listen before Talk. For networks with high load, improvements are achieved by a more complex scheduled MAC. Our model serves as a basis for future energy consumption studies, conducted through measurements or simulations.}, author = {Loh, Frank and Raffeck, Simon and Geißler, Stefan and Hoßfeld, Tobias}, booktitle = {18th International Conference on Wireless and Mobile Computing, Networking and Communications (WiMob)}, keywords = {5mart}, month = 10, title = {Generic Model to Quantify Energy Consumption for Different LoRaWAN Channel Access Methods}, year = 2022 }
Oberdörfer, S., Schraudt, D., Latoschik, M.E.: Embodied Gambling–Investigating the Influence of Level of Embodiment, Avatar Appearance, and Virtual Environment Design on an Online VR Slot Machine. Frontiers in Virtual Reality. 3, (2022).
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Slot machines are one of the most played games by players suffering from gambling disorder. New technologies like immersive Virtual Reality (VR) offer more possibilities to exploit erroneous beliefs in the context of gambling. Recent research indicates a higher risk potential when playing a slot machine in VR than on desktop. To continue this investigation, we evaluate the effects of providing different degrees of embodiment, i.e., minimal and full embodiment. The avatars used for the full embodiment further differ in their appearance, i.e., they elicit a high or a low socio-economic status. The virtual environment (VE) design can cause a potential influence on the overall gambling behavior. Thus, we also embed the slot machine in two different VEs that differ in their emotional design: a colorful underwater playground environment and a virtual counterpart of our lab. These design considerations resulted in four different versions of the same VR slot machine: 1) full embodiment with high socio-economic status, 2) full embodiment with low socio-economic status, 3) minimal embodiment playground VE, and 4) minimal embodiment laboratory VE. Both full embodiment versions also used the playground VE. We determine the risk potential by logging gambling frequency as well as stake size, and measuring harm-inducing factors, i.e., dissociation, urge to gamble, dark flow, and illusion of control, using questionnaires. Following a between groups experimental design, 82 participants played for 20 game rounds one of the four versions. We recruited our sample from the students enrolled at the University of Würzburg. Our safety protocol ensured that only participants without any recent gambling activity took part in the experiment. In this comparative user study, we found no effect of the embodiment nor VE design on neither the gambling frequency, stake sizes, nor risk potential. However, our results provide further support for the hypothesis of the higher visual angle on gambling stimuli and hence the increased emotional response being the true cause for the higher risk potential.

@article{oberdorfer2022embodied, abstract = {Slot machines are one of the most played games by players suffering from gambling disorder. New technologies like immersive Virtual Reality (VR) offer more possibilities to exploit erroneous beliefs in the context of gambling. Recent research indicates a higher risk potential when playing a slot machine in VR than on desktop. To continue this investigation, we evaluate the effects of providing different degrees of embodiment, i.e., minimal and full embodiment. The avatars used for the full embodiment further differ in their appearance, i.e., they elicit a high or a low socio-economic status. The virtual environment (VE) design can cause a potential influence on the overall gambling behavior. Thus, we also embed the slot machine in two different VEs that differ in their emotional design: a colorful underwater playground environment and a virtual counterpart of our lab. These design considerations resulted in four different versions of the same VR slot machine: 1) full embodiment with high socio-economic status, 2) full embodiment with low socio-economic status, 3) minimal embodiment playground VE, and 4) minimal embodiment laboratory VE. Both full embodiment versions also used the playground VE. We determine the risk potential by logging gambling frequency as well as stake size, and measuring harm-inducing factors, i.e., dissociation, urge to gamble, dark flow, and illusion of control, using questionnaires. Following a between groups experimental design, 82 participants played for 20 game rounds one of the four versions. We recruited our sample from the students enrolled at the University of Würzburg. Our safety protocol ensured that only participants without any recent gambling activity took part in the experiment. In this comparative user study, we found no effect of the embodiment nor VE design on neither the gambling frequency, stake sizes, nor risk potential. However, our results provide further support for the hypothesis of the higher visual angle on gambling stimuli and hence the increased emotional response being the true cause for the higher risk potential.}, author = {Oberdörfer, Sebastian and Schraudt, David and Latoschik, Marc Erich}, journal = {Frontiers in Virtual Reality}, keywords = {oberdoerfer}, title = {Embodied Gambling–Investigating the Influence of Level of Embodiment, Avatar Appearance, and Virtual Environment Design on an Online VR Slot Machine}, volume = 3, year = 2022 }
Seufert, A., Poignée, F., Hoßfeld, T., Seufert, M.: Pandemic in the Digital Age: Analyzing WhatsApp Communication Behavior before, during, and after the COVID-19 Lockdown. Humanities and Social Sciences Communications. 9, 140 (1–9) (2022).
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The strict restrictions introduced by the COVID-19 lockdowns, which started from March 2020, changed people’s daily lives and habits on many different levels. In this work, we investigate the impact of the lockdown on the communication behavior in the mobile instant messaging application WhatsApp. Our evaluations are based on a large dataset of 2577 private chat histories with 25,378,093 messages from 51,973 users. The analysis of the one-to-one and group conversations confirms that the lockdown severely altered the communication in WhatsApp chats compared to pre-pandemic time ranges. In particular, we observe short-term effects, which caused an increased message frequency in the first lockdown months and a shifted communication activity during the day in March and April 2020. Moreover, we also see long-term effects of the ongoing pandemic situation until February 2021, which indicate a change of communication behavior towards more regular messaging, as well as a persisting change in activity during the day. The results of our work show that even anonymized chat histories can tell us a lot about people’s behavior and especially behavioral changes during the COVID-19 pandemic and thus are of great relevance for behavioral researchers. Furthermore, looking at the pandemic from an Internet provider perspective, these insights can be used during the next pandemic, or if the current COVID-19 situation worsens, to adapt communication networks to the changed usage behavior early on and thus avoid network congestion.

@article{info3-article-2022-14, abstract = {The strict restrictions introduced by the COVID-19 lockdowns, which started from March 2020, changed people’s daily lives and habits on many different levels. In this work, we investigate the impact of the lockdown on the communication behavior in the mobile instant messaging application WhatsApp. Our evaluations are based on a large dataset of 2577 private chat histories with 25,378,093 messages from 51,973 users. The analysis of the one-to-one and group conversations confirms that the lockdown severely altered the communication in WhatsApp chats compared to pre-pandemic time ranges. In particular, we observe short-term effects, which caused an increased message frequency in the first lockdown months and a shifted communication activity during the day in March and April 2020. Moreover, we also see long-term effects of the ongoing pandemic situation until February 2021, which indicate a change of communication behavior towards more regular messaging, as well as a persisting change in activity during the day. The results of our work show that even anonymized chat histories can tell us a lot about people’s behavior and especially behavioral changes during the COVID-19 pandemic and thus are of great relevance for behavioral researchers. Furthermore, looking at the pandemic from an Internet provider perspective, these insights can be used during the next pandemic, or if the current COVID-19 situation worsens, to adapt communication networks to the changed usage behavior early on and thus avoid network congestion.}, author = {Seufert, Anika and Poignée, Fabian and Hoßfeld, Tobias and Seufert, Michael}, journal = {Humanities and Social Sciences Communications}, keywords = {ucn}, month = 4, number = 1, pages = {140 (1-9)}, title = {Pandemic in the Digital Age: Analyzing WhatsApp Communication Behavior before, during, and after the COVID-19 Lockdown}, volume = 9, year = 2022 }
Halbig, A., Babu, S.K., Gatter, S., Latoschik, M.E., Brukamp, K., von Mammen, S.: Opportunities and Challenges of Virtual Reality in Healthcare – A Domain Experts Inquiry. Frontiers in Virtual Reality. 3, (2022).
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- [ DOI ]
In recent years, the applications and accessibility of Virtual Reality (VR) for the healthcare sector have continued to grow. However, so far, most VR applications are only relevant in research settings. Information about what healthcare professionals would need to independently integrate VR applications into their daily working routines is missing. The actual needs and concerns of the people who work in the healthcare sector are often disregarded in the development of VR applications, even though they are the ones who are supposed to use them in practice. By means of this study, we systematically involve health professionals in the development process of VR applications. In particular, we conducted an online survey with 102 healthcare professionals based on a video prototype which demonstrates a software platform that allows them to create and utilise VR experiences on their own. For this study, we adapted and extended the Technology Acceptance Model (TAM). The survey focused on the perceived usefulness and the ease of use of such a platform, as well as the attitude and ethical concerns the users might have. The results show a generally positive attitude toward such a software platform. The users can imagine various use cases in different health domains. However, the perceived usefulness is tied to the actual ease of use of the platform and sufficient support for learning and working with the platform. In the discussion, we explain how these results can be generalized to facilitate the integration of VR in healthcare practice.

@article{halbig:2022q, abstract = {In recent years, the applications and accessibility of Virtual Reality (VR) for the healthcare sector have continued to grow. However, so far, most VR applications are only relevant in research settings. Information about what healthcare professionals would need to independently integrate VR applications into their daily working routines is missing. The actual needs and concerns of the people who work in the healthcare sector are often disregarded in the development of VR applications, even though they are the ones who are supposed to use them in practice. By means of this study, we systematically involve health professionals in the development process of VR applications. In particular, we conducted an online survey with 102 healthcare professionals based on a video prototype which demonstrates a software platform that allows them to create and utilise VR experiences on their own. For this study, we adapted and extended the Technology Acceptance Model (TAM). The survey focused on the perceived usefulness and the ease of use of such a platform, as well as the attitude and ethical concerns the users might have. The results show a generally positive attitude toward such a software platform. The users can imagine various use cases in different health domains. However, the perceived usefulness is tied to the actual ease of use of the platform and sufficient support for learning and working with the platform. In the discussion, we explain how these results can be generalized to facilitate the integration of VR in healthcare practice.}, author = {Halbig, Andreas and Babu, Sooraj K. and Gatter, Shirin and Latoschik, Marc Erich and Brukamp, Kirsten and von Mammen, Sebastian}, journal = {Frontiers in Virtual Reality}, keywords = {via-vr}, title = {Opportunities and Challenges of Virtual Reality in Healthcare – A Domain Experts Inquiry}, volume = 3, year = 2022 }
Loh, F., Mehling, N., Hoßfeld, T.: Towards LoRaWAN without Data Loss: Studying the Performance of Different Channel Access Approaches. Sensors. (2022).
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The Long Range Wide Area Network (LoRaWAN) is one of the fastest growing Internet of Things (IoT) access protocols. It operates in the license free 868 MHz band and gives everyone the possibility to create their own small sensor networks. The drawback of this technology is often unscheduled or random channel access, which leads to message collisions and potential data loss. For that reason, recent literature studies alternative approaches for LoRaWAN channel access. In this work, state-of-the-art random channel access is compared with alternative approaches from the litera- ture by means of collision probability. Furthermore, a time scheduled channel access methodology is presented to completely avoid collisions in LoRaWAN. For this approach, an exhaustive simulation study was conducted and the performance was evaluated with random access cross-traffic. In a general theoretical analysis the limits of the time scheduled approach are discussed to comply with duty cycle regulations in LoRaWAN.

@article{info3-inproceedings-2022-3, abstract = {The Long Range Wide Area Network (LoRaWAN) is one of the fastest growing Internet of Things (IoT) access protocols. It operates in the license free 868 MHz band and gives everyone the possibility to create their own small sensor networks. The drawback of this technology is often unscheduled or random channel access, which leads to message collisions and potential data loss. For that reason, recent literature studies alternative approaches for LoRaWAN channel access. In this work, state-of-the-art random channel access is compared with alternative approaches from the litera- ture by means of collision probability. Furthermore, a time scheduled channel access methodology is presented to completely avoid collisions in LoRaWAN. For this approach, an exhaustive simulation study was conducted and the performance was evaluated with random access cross-traffic. In a general theoretical analysis the limits of the time scheduled approach are discussed to comply with duty cycle regulations in LoRaWAN.}, author = {Loh, Frank and Mehling, Noah and Hoßfeld, Tobias}, journal = {Sensors}, keywords = {5mart}, month = 1, title = {Towards LoRaWAN without Data Loss: Studying the Performance of Different Channel Access Approaches}, year = 2022 }
Schell, C., Sieper, F., Latoschik, M.E.: Who is Alyx?, https://github.com/cschell/who-is-alyx, (2022).
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This dataset contains over 57 hours of motion and eye-tracking data from 37 players of the virtual reality game "Half-Life: Alyx". Each player played the game on two separate days for about 45 minutes using a HTC Vive Pro.

@dataset{who_is_alyx_2022, abstract = {This dataset contains over 57 hours of motion and eye-tracking data from 37 players of the virtual reality game "Half-Life: Alyx". Each player played the game on two separate days for about 45 minutes using a HTC Vive Pro.}, author = {Schell, Christian and Sieper, Fabian and Latoschik, Marc E.}, keywords = {myown}, month = {April}, title = {Who is Alyx?}, year = 2022 }
Hein, R., Steinbock, J., Eisenmann, M., Wienrich, C., Latoschik, M.E.: Virtual Reality im modernen Englischunterricht und das Potenzial für Inter- und Transkulturelles Lernen. MedienPädagogik Zeitschrift für Theorie und Praxis der Medienbildung. 47, 246–266 (2022).
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@article{hein2021medienpaed, author = {Hein, Rebecca and Steinbock, Jeanine and Eisenmann, Maria and Wienrich, Carolin and Latoschik, Marc Erich}, journal = {MedienPädagogik Zeitschrift für Theorie und Praxis der Medienbildung}, keywords = {rhein}, pages = {246-266}, title = {Virtual Reality im modernen Englischunterricht und das Potenzial für Inter- und Transkulturelles Lernen}, volume = 47, year = 2022 }
Hadry, M., Lesch, V., Kounev, S.: FADE: Towards Flexible and Adaptive Distance Estimation Considering Obstacles. Companion of the 13th ACM/SPEC International Conference on Performance Engineering (ICPE 2022). ACM (2022).
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@inproceedings{hadry2022towards, author = {Hadry, Marius and Lesch, Veronika and Kounev, Samuel}, booktitle = {Companion of the 13th ACM/SPEC International Conference on Performance Engineering (ICPE 2022)}, keywords = {cyber-physical_systems}, month = {April}, publisher = {ACM}, title = {FADE: Towards Flexible and Adaptive Distance Estimation Considering Obstacles}, year = 2022 }
Wolf, E., Fiedler, M.L., Döllinger, N., Wienrich, C., Latoschik, M.E.: Exploring Presence, Avatar Embodiment, and Body Perception with a Holographic Augmented Reality Mirror. 2022 IEEE Conference on Virtual Reality and 3D User Interfaces (VR). S. 350–359 (2022).
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The embodiment of avatars in virtual reality (VR) is a promising tool for enhancing the user's mental health. A great example is the treatment of body image disturbances, where eliciting a full-body illusion can help identify, visualize, and modulate persisting misperceptions. Augmented reality (AR) could complement recent advances in the field by incorporating real elements, such as the therapist or the user's real body, into therapeutic scenarios. However, research on the use of AR in this context is very sparse. Therefore, we present a holographic AR mirror system based on an optical see-through (OST) device and markerless body tracking, collect valuable qualitative feedback regarding its user experience, and compare quantitative results regarding presence, embodiment, and body weight perception to similar systems using video see-through (VST) AR and VR. For our OST AR system, a total of 27 normal-weight female participants provided predominantly positive feedback on display properties (field of view, luminosity, and transparency of virtual objects), body tracking, and the perception of the avatar’s appearance and movements. In the quantitative comparison to the VST AR and VR systems, participants reported significantly lower feelings of presence, while they estimated the body weight of the generic avatar significantly higher when using our OST AR system. For virtual body ownership and agency, we found only partially significant differences. In summary, our study shows the general applicability of OST AR in the given context offering huge potential in future therapeutic scenarios. However, the comparative evaluation between OST AR, VST AR, and VR also revealed significant differences in relevant measures. Future work is mandatory to corroborate our findings and to classify the significance in a therapeutic context.

@inproceedings{wolf2022holographic, abstract = {The embodiment of avatars in virtual reality (VR) is a promising tool for enhancing the user's mental health. A great example is the treatment of body image disturbances, where eliciting a full-body illusion can help identify, visualize, and modulate persisting misperceptions. Augmented reality (AR) could complement recent advances in the field by incorporating real elements, such as the therapist or the user's real body, into therapeutic scenarios. However, research on the use of AR in this context is very sparse. Therefore, we present a holographic AR mirror system based on an optical see-through (OST) device and markerless body tracking, collect valuable qualitative feedback regarding its user experience, and compare quantitative results regarding presence, embodiment, and body weight perception to similar systems using video see-through (VST) AR and VR. For our OST AR system, a total of 27 normal-weight female participants provided predominantly positive feedback on display properties (field of view, luminosity, and transparency of virtual objects), body tracking, and the perception of the avatar’s appearance and movements. In the quantitative comparison to the VST AR and VR systems, participants reported significantly lower feelings of presence, while they estimated the body weight of the generic avatar significantly higher when using our OST AR system. For virtual body ownership and agency, we found only partially significant differences. In summary, our study shows the general applicability of OST AR in the given context offering huge potential in future therapeutic scenarios. However, the comparative evaluation between OST AR, VST AR, and VR also revealed significant differences in relevant measures. Future work is mandatory to corroborate our findings and to classify the significance in a therapeutic context.}, author = {Wolf, Erik and Fiedler, Marie Luisa and Döllinger, Nina and Wienrich, Carolin and Latoschik, Marc Erich}, booktitle = {2022 IEEE Conference on Virtual Reality and 3D User Interfaces (VR)}, keywords = {vitras}, pages = {350-359}, title = {Exploring Presence, Avatar Embodiment, and Body Perception with a Holographic Augmented Reality Mirror}, year = 2022 }
Bauer, A., Straesser, M., Beierlieb, L., Meissner, M., Kounev, S.: Automated Triage of Performance Change Points Using Time Series Analysis and Machine Learning. Proceedings of the 2022 ACM/SPEC on International Conference on Performance Engineering. ACM (2022).
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@conference{bauer2022automated, author = {Bauer, André and Straesser, Martin and Beierlieb, Lukas and Meissner, Maximilian and Kounev, Samuel}, booktitle = {Proceedings of the 2022 ACM/SPEC on International Conference on Performance Engineering}, keywords = {timeseries}, month = 4, publisher = {ACM}, title = {Automated Triage of Performance Change Points Using Time Series Analysis and Machine Learning}, year = 2022 }
Leznik, M., Grohmann, J., Kliche, N., Bauer, A., Seybold, D., Eismann, S., Kounev, S., Domaschka, J.: Same, Same, but Dissimilar: Exploring Measurements for Workload Time-Series Similarity. Proceedings of the 2022 ACM/SPEC on International Conference on Performance Engineering. S. 89–96. Association for Computing Machinery, New York, NY, USA (2022).
- [ Abstract ]
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Benchmarking is a core element in the toolbox of most systems researchers and is used for analyzing, comparing, and validating complex systems. In the quest for reliable benchmark results, a consensus has formed that a significant experiment must be based on multiple runs. To interpret these runs, mean and standard deviation are often used. In case of experiments where each run produces a time series, applying and comparing the mean is not easily applicable and not necessarily statistically sound. Such an approach ignores the possibility of significant differences between runs with a similar average. In order to verify this hypothesis, we conducted a survey of 1,112 publications of selected performance engineering and systems conferences canvassing open data sets from performance experiments. The identified 3 data sets purely rely on average and standard deviation. Therefore, we propose a novel analysis approach based on similarity analysis to enhance the reliability of performance evaluations. Our approach evaluates 12 (dis-)similarity measures with respect to their applicability in analysing performance measurements and identifies four suitable similarity measures. We validate our approach by demonstrating the increase in reliability for the data sets found in the survey.

@inproceedings{leznik2022dissimilar, abstract = {Benchmarking is a core element in the toolbox of most systems researchers and is used for analyzing, comparing, and validating complex systems. In the quest for reliable benchmark results, a consensus has formed that a significant experiment must be based on multiple runs. To interpret these runs, mean and standard deviation are often used. In case of experiments where each run produces a time series, applying and comparing the mean is not easily applicable and not necessarily statistically sound. Such an approach ignores the possibility of significant differences between runs with a similar average. In order to verify this hypothesis, we conducted a survey of 1,112 publications of selected performance engineering and systems conferences canvassing open data sets from performance experiments. The identified 3 data sets purely rely on average and standard deviation. Therefore, we propose a novel analysis approach based on similarity analysis to enhance the reliability of performance evaluations. Our approach evaluates 12 (dis-)similarity measures with respect to their applicability in analysing performance measurements and identifies four suitable similarity measures. We validate our approach by demonstrating the increase in reliability for the data sets found in the survey.}, address = {New York, NY, USA}, author = {Leznik, Mark and Grohmann, Johannes and Kliche, Nina and Bauer, Andr\'{e} and Seybold, Daniel and Eismann, Simon and Kounev, Samuel and Domaschka, J\"{o}rg}, booktitle = {Proceedings of the 2022 ACM/SPEC on International Conference on Performance Engineering}, keywords = {myown}, pages = {89–96}, publisher = {Association for Computing Machinery}, series = {ICPE '22}, title = {Same, Same, but Dissimilar: Exploring Measurements for Workload Time-Series Similarity}, year = 2022 }
Straesser, M., Grohmann, J., von Kistowski, J., Eismann, S., Bauer, A., Kounev, S.: Why Is It Not Solved Yet? Challenges for Production-Ready Autoscaling. Proceedings of the 2022 ACM/SPEC on International Conference on Performance Engineering. S. 105–115. Association for Computing Machinery, New York, NY, USA (2022).
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Autoscaling is a task of major importance in the cloud computing domain as it directly affects both operating costs and customer experience. Although there has been active research in this area for over ten years now, there is still a significant gap between the proposed methods in the literature and the deployed autoscalers in practice. Hence, many research autoscalers do not find their way into production deployments. This paper describes six core challenges that arise in production systems that are still not solved by most research autoscalers. We illustrate these problems through experiments in a realistic cloud environment with a real-world multi-service business application and show that commonly used autoscalers have various shortcomings. In addition, we analyze the behavior of overloaded services and show that these can be problematic for existing autoscalers. Generally, we analyze that these challenges are only insufficiently addressed in the literature and conclude that future scaling approaches should focus on the needs of production systems.

@inproceedings{10.1145/3489525.3511680, abstract = {Autoscaling is a task of major importance in the cloud computing domain as it directly affects both operating costs and customer experience. Although there has been active research in this area for over ten years now, there is still a significant gap between the proposed methods in the literature and the deployed autoscalers in practice. Hence, many research autoscalers do not find their way into production deployments. This paper describes six core challenges that arise in production systems that are still not solved by most research autoscalers. We illustrate these problems through experiments in a realistic cloud environment with a real-world multi-service business application and show that commonly used autoscalers have various shortcomings. In addition, we analyze the behavior of overloaded services and show that these can be problematic for existing autoscalers. Generally, we analyze that these challenges are only insufficiently addressed in the literature and conclude that future scaling approaches should focus on the needs of production systems.}, address = {New York, NY, USA}, author = {Straesser, Martin and Grohmann, Johannes and von Kistowski, J\'{o}akim and Eismann, Simon and Bauer, Andr\'{e} and Kounev, Samuel}, booktitle = {Proceedings of the 2022 ACM/SPEC on International Conference on Performance Engineering}, keywords = {myown}, pages = {105–115}, publisher = {Association for Computing Machinery}, series = {ICPE '22}, title = {Why Is It Not Solved Yet? Challenges for Production-Ready Autoscaling}, year = 2022 }
Palmisano, C., Kullmann, P., Hanafi, I., Verrecchia, M., Latoschik, M.E., Canessa, A., Fischbach, M., Isaias, I.U.: A Fully-Immersive Virtual Reality Setup to Study Gait Modulation. Frontiers in Human Neuroscience. 16, (2022).
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Objective: Gait adaptation to environmental challenges is fundamental for independent and safe community ambulation. The possibility of precisely studying gait modulation using standardized protocols of gait analysis closely resembling everyday life scenarios is still an unmet need.Methods: We have developed a fully-immersive virtual reality (VR) environment where subjects have to adjust their walking pattern to avoid collision with a virtual agent (VA) crossing their gait trajectory. We collected kinematic data of 12 healthy young subjects walking in real world (RW) and in the VR environment, both with (VR/A+) and without (VR/A-) the VA perturbation. The VR environment closely resembled the RW scenario of the gait laboratory. To ensure standardization of the obstacle presentation the starting time speed and trajectory of the VA were defined using the kinematics of the participant as detected online during each walking trial.Results: We did not observe kinematic differences between walking in RW and VR/A-, suggesting that our VR environment per se might not induce significant changes in the locomotor pattern. When facing the VA all subjects consistently reduced stride length and velocity while increasing stride duration. Trunk inclination and mediolateral trajectory deviation also facilitated avoidance of the obstacle.Conclusions: This proof-of-concept study shows that our VR/A+ paradigm effectively induced a timely gait modulation in a standardized immersive and realistic scenario. This protocol could be a powerful research tool to study gait modulation and its derangements in relation to aging and clinical conditions.

@article{10.3389/fnhum.2022.783452, abstract = {Objective: Gait adaptation to environmental challenges is fundamental for independent and safe community ambulation. The possibility of precisely studying gait modulation using standardized protocols of gait analysis closely resembling everyday life scenarios is still an unmet need.Methods: We have developed a fully-immersive virtual reality (VR) environment where subjects have to adjust their walking pattern to avoid collision with a virtual agent (VA) crossing their gait trajectory. We collected kinematic data of 12 healthy young subjects walking in real world (RW) and in the VR environment, both with (VR/A+) and without (VR/A-) the VA perturbation. The VR environment closely resembled the RW scenario of the gait laboratory. To ensure standardization of the obstacle presentation the starting time speed and trajectory of the VA were defined using the kinematics of the participant as detected online during each walking trial.Results: We did not observe kinematic differences between walking in RW and VR/A-, suggesting that our VR environment per se might not induce significant changes in the locomotor pattern. When facing the VA all subjects consistently reduced stride length and velocity while increasing stride duration. Trunk inclination and mediolateral trajectory deviation also facilitated avoidance of the obstacle.Conclusions: This proof-of-concept study shows that our VR/A+ paradigm effectively induced a timely gait modulation in a standardized immersive and realistic scenario. This protocol could be a powerful research tool to study gait modulation and its derangements in relation to aging and clinical conditions.}, author = {Palmisano, Chiara and Kullmann, Peter and Hanafi, Ibrahem and Verrecchia, Marta and Latoschik, Marc Erich and Canessa, Andrea and Fischbach, Martin and Isaias, Ioannis Ugo}, journal = {Frontiers in Human Neuroscience}, keywords = {myown}, title = {A Fully-Immersive Virtual Reality Setup to Study Gait Modulation}, volume = 16, year = 2022 }
Kounev, S., van Hoorn, A., Straesser, M., Bauer, A.: SPEC Research Group Newsletter, Issue 11, (2022).
- [ BibTeX ]
@misc{SPEC-RG-NEWSLETTER-11, author = {Kounev, Samuel and van Hoorn, Andre and Straesser, Martin and Bauer, Andr{é}}, keywords = {myown}, month = {April}, note = {Published by Standard Performance Evaluation Corporation (SPEC)}, title = {SPEC Research Group Newsletter, Issue 11}, year = 2022 }
Straesser, M., Grohmann, J., von Kistowski, J., Eismann, S., Bauer, A., Kounev, S.: Why Is It Not Solved Yet? Challenges for Production-Ready Autoscaling. Proceedings of the 2022 ACM/SPEC on International Conference on Performance Engineering. S. 105–115. Association for Computing Machinery, New York, NY, USA (2022).
- [ Abstract ]
- [ BibTeX ]
- [ URL ]
Autoscaling is a task of major importance in the cloud computing domain as it directly affects both operating costs and customer experience. Although there has been active research in this area for over ten years now, there is still a significant gap between the proposed methods in the literature and the deployed autoscalers in practice. Hence, many research autoscalers do not find their way into production deployments. This paper describes six core challenges that arise in production systems that are still not solved by most research autoscalers. We illustrate these problems through experiments in a realistic cloud environment with a real-world multi-service business application and show that commonly used autoscalers have various shortcomings. In addition, we analyze the behavior of overloaded services and show that these can be problematic for existing autoscalers. Generally, we analyze that these challenges are only insufficiently addressed in the literature and conclude that future scaling approaches should focus on the needs of production systems.

@inproceedings{10.1145/3489525.3511680, abstract = {Autoscaling is a task of major importance in the cloud computing domain as it directly affects both operating costs and customer experience. Although there has been active research in this area for over ten years now, there is still a significant gap between the proposed methods in the literature and the deployed autoscalers in practice. Hence, many research autoscalers do not find their way into production deployments. This paper describes six core challenges that arise in production systems that are still not solved by most research autoscalers. We illustrate these problems through experiments in a realistic cloud environment with a real-world multi-service business application and show that commonly used autoscalers have various shortcomings. In addition, we analyze the behavior of overloaded services and show that these can be problematic for existing autoscalers. Generally, we analyze that these challenges are only insufficiently addressed in the literature and conclude that future scaling approaches should focus on the needs of production systems.}, address = {New York, NY, USA}, author = {Straesser, Martin and Grohmann, Johannes and von Kistowski, J\'{o}akim and Eismann, Simon and Bauer, Andr\'{e} and Kounev, Samuel}, booktitle = {Proceedings of the 2022 ACM/SPEC on International Conference on Performance Engineering}, keywords = {myown}, pages = {105–115}, publisher = {Association for Computing Machinery}, series = {ICPE '22}, title = {Why Is It Not Solved Yet? Challenges for Production-Ready Autoscaling}, year = 2022 }
und David Schantz und Julian Gröh und Andreas Knote und Prof. Dr. Sebastian von Mammen und Prof. Dr. Juliano Cabral, A.L.: bioDIVERsity. Ein Computerspiel gegen das Imageproblem von Wasserpflanzen. Mitteilungen der Fränkischen Geographischen Gesellschaft. 29–36 (2022).
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Wasserpflanzen haben ein Imageproblem: Sie stören vermeintlich beim Baden in Seen, was zu panikartigenReaktionen führen kann. Begriffe wie „Schlingpflanzen“ und „Veralgung“ werden falsch verwendet odersind negativ konnotiert. Zudem sieht man Wasserpflanzen kaum, da sie überwiegend unter der Wasseroberflächewachsen. Ihre vielen wertvollen Funktionen im Ökosystem See bleiben daher oft unerkannt undsind durch die schlechte Erreichbarkeit und Erfahrbarkeit nur schwer zu vermitteln.Virtuelle Medien eröffnen eine neue Möglichkeit, schwierig erreichbare Orte erfahrbar zu machen. Fürdie Vermittlung von Umweltthemen – gerade an eine jüngere Zielgruppe – wird ein großes Potential indigitalen Spielen und Simulationen (Computerspiele, Apps, Virtual Reality-Spiele), speziell sogenanntenSerious Games, gesehen.Ein Prototyp für das Serious Game bioDIVERsity wurde im Rahmen eines interdisziplinären Kurses derArbeitsgruppe Games Engineering am Institut für Informatik in Zusammenarbeit mit dem Center for Computationaland Theoretical Biology an der Universität Würzburg entwickelt. Ziel des Spiels ist es, KindernKenntnisse über das Ökosystem See und die Auswirkungen der Wasserqualität und der Klimabedingungenauf Wasserpflanzen zu vermitteln. Darüber hinaus soll ein Bewusstsein für dieses Ökosystem und die Auswirkungenmenschlicher Eingriffe entstehen.

@article{Lewerentz:2022aa, abstract = {Wasserpflanzen haben ein Imageproblem: Sie stören vermeintlich beim Baden in Seen, was zu panikartigenReaktionen führen kann. Begriffe wie „Schlingpflanzen“ und „Veralgung“ werden falsch verwendet odersind negativ konnotiert. Zudem sieht man Wasserpflanzen kaum, da sie überwiegend unter der Wasseroberflächewachsen. Ihre vielen wertvollen Funktionen im Ökosystem See bleiben daher oft unerkannt undsind durch die schlechte Erreichbarkeit und Erfahrbarkeit nur schwer zu vermitteln.Virtuelle Medien eröffnen eine neue Möglichkeit, schwierig erreichbare Orte erfahrbar zu machen. Fürdie Vermittlung von Umweltthemen – gerade an eine jüngere Zielgruppe – wird ein großes Potential indigitalen Spielen und Simulationen (Computerspiele, Apps, Virtual Reality-Spiele), speziell sogenanntenSerious Games, gesehen.Ein Prototyp für das Serious Game bioDIVERsity wurde im Rahmen eines interdisziplinären Kurses derArbeitsgruppe Games Engineering am Institut für Informatik in Zusammenarbeit mit dem Center for Computationaland Theoretical Biology an der Universität Würzburg entwickelt. Ziel des Spiels ist es, KindernKenntnisse über das Ökosystem See und die Auswirkungen der Wasserqualität und der Klimabedingungenauf Wasserpflanzen zu vermitteln. Darüber hinaus soll ein Bewusstsein für dieses Ökosystem und die Auswirkungenmenschlicher Eingriffe entstehen.}, author = {und David Schantz und Julian Gröh und Andreas Knote und Prof. Dr. Sebastian von Mammen und Prof. Dr. Juliano Cabral, Anne Lewerentz}, journal = {Mitteilungen der Fränkischen Geographischen Gesellschaft}, keywords = {myown}, number = 67, pages = {29–36}, title = {bioDIVERsity. Ein Computerspiel gegen das Imageproblem von Wasserpflanzen}, year = 2022 }
Eismann, S., Costa, D., Liao, L., Bezemer, C.-P., Shang, W., van Hoorn, A., Kounev, S.: A case study on the stability of performance tests for serverless applications. Journal of Systems and Software (JSS). 189, (2022).
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Context: While in serverless computing, application resource management and operational concerns are generally delegated to the cloud provider, ensuring that serverless applications meet their performance requirements is still a responsibility of the developers. Performance testing is a commonly used performance assessment practice; however, it traditionally requires visibility of the resource environment. Objective: In this study, we investigate whether performance tests of serverless applications are stable, that is, if their results are reproducible, and what implications the serverless paradigm has for performance tests. Method: We conduct a case study where we collect two datasets of performance test results: (a) repetitions of performance tests for varying memory size and load intensities and (b) three repetitions of the same performance test every day for ten months. Results: We find that performance tests of serverless applications are comparatively stable if conducted on the same day. However, we also observe short-term performance variations and frequent long-term performance changes. Conclusion: Performance tests for serverless applications can be stable; however, the serverless model impacts the planning, execution, and analysis of performance tests.

@article{eismann2022study, abstract = {Context: While in serverless computing, application resource management and operational concerns are generally delegated to the cloud provider, ensuring that serverless applications meet their performance requirements is still a responsibility of the developers. Performance testing is a commonly used performance assessment practice; however, it traditionally requires visibility of the resource environment. Objective: In this study, we investigate whether performance tests of serverless applications are stable, that is, if their results are reproducible, and what implications the serverless paradigm has for performance tests. Method: We conduct a case study where we collect two datasets of performance test results: (a) repetitions of performance tests for varying memory size and load intensities and (b) three repetitions of the same performance test every day for ten months. Results: We find that performance tests of serverless applications are comparatively stable if conducted on the same day. However, we also observe short-term performance variations and frequent long-term performance changes. Conclusion: Performance tests for serverless applications can be stable; however, the serverless model impacts the planning, execution, and analysis of performance tests.}, author = {Eismann, Simon and Costa, Diego and Liao, Lizhi and Bezemer, Cor-Paul and Shang, Weiyi and van Hoorn, André and Kounev, Samuel}, journal = {Journal of Systems and Software (JSS)}, keywords = {myown}, title = {A case study on the stability of performance tests for serverless applications}, volume = 189, year = 2022 }
Döllinger, N., Wolf, E., Mal, D., Erdmannsdörfer, N., Botsch, M., Latoschik, M.E., Wienrich, C.: Virtual Reality for Mind and Body: Does the Sense of Embodiment Towards a Virtual Body Affect Physical Body Awareness?. CHI 22 Conference on Human Factors in Computing Systems Extended Abstracts. S. 7 (2022).
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- [ DOI ]
Mind-body therapies aim to improve health by combining physical and mental exercises. Recent developments tend to incorporate virtual reality (VR) into their design and execution, but there is a lack of research concerning the inclusion of virtual bodies and their effect on body awareness in these designs. In this study, 24 participants performed in-VR body awareness movement tasks in front of a virtual mirror while embodying a photorealistic, personalized avatar. Subsequently, they performed a heartbeat counting task and rated their perceived body awareness and sense of embodiment towards the avatar. We found a significant relationship between sense of embodiment and self-reported body awareness but not between sense of embodiment and heartbeat counting. Future work can build on these findings and further explore the relationship between avatar embodiment and body awareness.

@inproceedings{dollinger2022virtual, abstract = {Mind-body therapies aim to improve health by combining physical and mental exercises. Recent developments tend to incorporate virtual reality (VR) into their design and execution, but there is a lack of research concerning the inclusion of virtual bodies and their effect on body awareness in these designs. In this study, 24 participants performed in-VR body awareness movement tasks in front of a virtual mirror while embodying a photorealistic, personalized avatar. Subsequently, they performed a heartbeat counting task and rated their perceived body awareness and sense of embodiment towards the avatar. We found a significant relationship between sense of embodiment and self-reported body awareness but not between sense of embodiment and heartbeat counting. Future work can build on these findings and further explore the relationship between avatar embodiment and body awareness.}, author = {Döllinger, Nina and Wolf, Erik and Mal, David and Erdmannsdörfer, Nico and Botsch, Mario and Latoschik, Marc Erich and Wienrich, Carolin}, journal = {CHI 22 Conference on Human Factors in Computing Systems Extended Abstracts}, keywords = {vitras}, month = {April}, pages = 7, title = {Virtual Reality for Mind and Body: Does the Sense of Embodiment Towards a Virtual Body Affect Physical Body Awareness?}, year = 2022 }
Raffeck, S., Geißler, S., Krolikowski, M., Gebert, S., Hoßfeld, T.: Data Usage in IoT: A Characterization of GTP Tunnels in M2M Mobile Networks. 2nd IFIP/IEEE International workshop on Fully-Flexible Internet Architectures and Protocols for the Next-Generation Tactile Internet (FlexNGIA) (2022).
- [ Abstract ]
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IoT and M2M devices have seen a significant growth in usage and deployment over the last years. Gaining insight into device and data usage behavior exhibited by the participants of mobile networks is elementary for MNO and MVNO to scale their networks and provide a reliable service. This work aims to make use of its first of a kind dataset, spanning multiple countries and MNO, to provide a detailed characterization of GTP tunnels and devices. To this end, general statistics are used to describe the observed data traffic focusing on the distribution of the tunnel duration and volume as well as periodic device behavior. An approximate metric is introduced to analyze the periodicity and synchronicity of IoT devices. Lastly, we publish the data investigated in this work and provide a large scale dataset on the data usage behavior of IoT devices to interested researchers.

@inproceedings{info3-inproceedings-2022-5, abstract = {IoT and M2M devices have seen a significant growth in usage and deployment over the last years. Gaining insight into device and data usage behavior exhibited by the participants of mobile networks is elementary for MNO and MVNO to scale their networks and provide a reliable service. This work aims to make use of its first of a kind dataset, spanning multiple countries and MNO, to provide a detailed characterization of GTP tunnels and devices. To this end, general statistics are used to describe the observed data traffic focusing on the distribution of the tunnel duration and volume as well as periodic device behavior. An approximate metric is introduced to analyze the periodicity and synchronicity of IoT devices. Lastly, we publish the data investigated in this work and provide a large scale dataset on the data usage behavior of IoT devices to interested researchers.}, author = {Raffeck, Simon and Geißler, Stefan and Krolikowski, Michael and Gebert, Steffen and Hoßfeld, Tobias}, booktitle = {2nd IFIP/IEEE International workshop on Fully-Flexible Internet Architectures and Protocols for the Next-Generation Tactile Internet (FlexNGIA)}, keywords = {can}, month = 4, title = {Data Usage in IoT: A Characterization of GTP Tunnels in M2M Mobile Networks}, year = 2022 }
Vomhoff, V., Geißler, S., Loh, F., Bauer, W., Hoßfeld, T.: Characterizing Mobile Signaling Anomalies in the Internet-of-Things. 2nd IFIP/IEEE International workshop on Fully-Flexible Internet Architectures and Protocols for the Next-Generation Tactile Internet (FlexNGIA) (2022).
- [ Abstract ]
- [ BibTeX ]
The development and adoption speed of new Internet of Things (IoT) devices and applications is constantly increasing. In particular in mobile networks, however, constant connectivity for all newly developed, globally spread, and occasionally geographically mobile devices is challenging. While the main business of current network operators is in particular, not to roam these new device generation between different networks, whereas new so-called Mobile Virtual Network Operators (MVNOs) arise with exactly this business case. They use already available Radio Access Networks and deploy SIM cards that are able to establish data connection everywhere on the basis of international roaming agreements. However, because of the complex interconnection of different systems, additional challenges arise. Outages in one network component might impact the whole system. In this work, we study these signaling anomalies called incidents based on a dataset received from a global MVNO. The goal of this work is to determine traffic characteristics during these incidents towards a better understanding of signaling traffic in IoT networks. Thus, this work can be seen as a fundamental basis to help operators in a characterization, and in particular prediction and avoidance of signaling incidents.

@inproceedings{info3-inproceedings-2022-4, abstract = {The development and adoption speed of new Internet of Things (IoT) devices and applications is constantly increasing. In particular in mobile networks, however, constant connectivity for all newly developed, globally spread, and occasionally geographically mobile devices is challenging. While the main business of current network operators is in particular, not to roam these new device generation between different networks, whereas new so-called Mobile Virtual Network Operators (MVNOs) arise with exactly this business case. They use already available Radio Access Networks and deploy SIM cards that are able to establish data connection everywhere on the basis of international roaming agreements. However, because of the complex interconnection of different systems, additional challenges arise. Outages in one network component might impact the whole system. In this work, we study these signaling anomalies called incidents based on a dataset received from a global MVNO. The goal of this work is to determine traffic characteristics during these incidents towards a better understanding of signaling traffic in IoT networks. Thus, this work can be seen as a fundamental basis to help operators in a characterization, and in particular prediction and avoidance of signaling incidents.}, author = {Vomhoff, Viktoria and Geißler, Stefan and Loh, Frank and Bauer, Wolfgang and Hoßfeld, Tobias}, booktitle = {2nd IFIP/IEEE International workshop on Fully-Flexible Internet Architectures and Protocols for the Next-Generation Tactile Internet (FlexNGIA)}, keywords = {can}, month = 4, title = {Characterizing Mobile Signaling Anomalies in the Internet-of-Things}, year = 2022 }
Loh, F., Mehling, N., Geißler, S., Hoßfeld, T.: Simulative Performance Study of Slotted Aloha for LoRaWAN Channel Access. IEEE/IFIP Network Operations and Management Symposium (2022).
- [ Abstract ]
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Future Internet of Things deployments generate a multitude of new challenges and opportunities. While 5G networks promise massive throughput rates with ultra low delays, many verticals in the areas of Industry 4.0, Smart City, or Smart Agriculture only transmit tiny amounts of data and instead demand high energy efficiency. This is addressed by access technologies like Low Power Wide Area Networks being com- plementary to high performance 5G networks. Especially Long Range Wide Area Network (LoRaWAN) promises transmissions across long distances with low energy requirements with the drawback of unreliable transmission due to potential message collisions through random channel access. For that reason, a broad parameter study simulation for LoRaWAN channel access with slotted Aloha is presented for real world scenarios and influences like clock drifts or cross traffic. The key impact factors of this channel access approach are studied with focus on the collision probability in various scenarios and simulation results are compared to the current state of the art. The contribution of this work are guidelines for parameter settings in a LoRaWAN with slotted Aloha channel access and performance comparisons for different settings. This information is crucial to scale and operate future LoRaWANs.

@inproceedings{info3-article-2022-13, abstract = {Future Internet of Things deployments generate a multitude of new challenges and opportunities. While 5G networks promise massive throughput rates with ultra low delays, many verticals in the areas of Industry 4.0, Smart City, or Smart Agriculture only transmit tiny amounts of data and instead demand high energy efficiency. This is addressed by access technologies like Low Power Wide Area Networks being com- plementary to high performance 5G networks. Especially Long Range Wide Area Network (LoRaWAN) promises transmissions across long distances with low energy requirements with the drawback of unreliable transmission due to potential message collisions through random channel access. For that reason, a broad parameter study simulation for LoRaWAN channel access with slotted Aloha is presented for real world scenarios and influences like clock drifts or cross traffic. The key impact factors of this channel access approach are studied with focus on the collision probability in various scenarios and simulation results are compared to the current state of the art. The contribution of this work are guidelines for parameter settings in a LoRaWAN with slotted Aloha channel access and performance comparisons for different settings. This information is crucial to scale and operate future LoRaWANs.}, author = {Loh, Frank and Mehling, Noah and Geißler, Stefan and Hoßfeld, Tobias}, booktitle = {IEEE/IFIP Network Operations and Management Symposium}, keywords = {can}, month = 4, title = {Simulative Performance Study of Slotted Aloha for LoRaWAN Channel Access}, year = 2022 }
Dietz, K., Gray, N., Seufert, M., Hoßfeld, T.: ML-based Performance Prediction of SDN using Simulated Data from Real and Synthetic Networks. 33th IEEE/IFIP Network Operations and Management Symposium (NOMS). , Budapest, Hungary (2022).
- [ BibTeX ]
@inproceedings{info3-inproceedings-2022-2, address = {Budapest, Hungary}, author = {Dietz, Katharina and Gray, Nicholas and Seufert, Michael and Hoßfeld, Tobias}, booktitle = {33th IEEE/IFIP Network Operations and Management Symposium (NOMS)}, keywords = {ucn}, month = 4, title = {ML-based Performance Prediction of SDN using Simulated Data from Real and Synthetic Networks}, year = 2022 }
Gutowski, G., Mittelst{\"a}dt, F., Rutter, I., Spoerhase, J., Wolff, A., Zink, J.: Coloring Mixed and Directional Interval Graphs. In: Angelini, P. und von Hanxleden, R. (hrsg.) Proc. 30th Int. Symp. Graph Drawing \& Network Vis. (GD’22). Springer-Verlag (2022).
- [ BibTeX ]
@inproceedings{gmrswz-cmdig-GD22, author = {Gutowski, Grzegorz and Mittelst{\"a}dt, Florian and Rutter, Ignaz and Spoerhase, Joachim and Wolff, Alexander and Zink, Johannes}, booktitle = {Proc. 30th Int. Symp. Graph Drawing \& Network Vis. (GD'22)}, editor = {Angelini, Patrizio and von Hanxleden, Reinhard}, keywords = {myown}, publisher = {Springer-Verlag}, series = {Lecture Notes in Computer Science}, title = {Coloring Mixed and Directional Interval Graphs}, year = 2022 }
Dietz, K., Seufert, M., Hoßfeld, T.: Comparing Traditional and GAN-based Approaches for the Synthesis of Wide Area Network Topologies. 18th International Conference on Network and Service Management (CNSM). , Thessaloniki, Greece (2022).
- [ BibTeX ]
@inproceedings{info3-inproceedings-2022-16, address = {Thessaloniki, Greece}, author = {Dietz, Katharina and Seufert, Michael and Hoßfeld, Tobias}, booktitle = {18th International Conference on Network and Service Management (CNSM)}, keywords = {ucn}, month = 10, title = {Comparing Traditional and GAN-based Approaches for the Synthesis of Wide Area Network Topologies}, year = 2022 }
Steinhaeusser, S.C., Oberdörfer, S., von Mammen, S., Latoschik, M.E., Lugrin, B.: Joyful Adventures and Frightening Places - Designing Emotion-Inducing Virtual Environments. Frontiers in Virtual Reality. (2022).
- [ BibTeX ]
- [ URL ]
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@article{steinhaeusser2022joyful, author = {Steinhaeusser, Sophia C and Oberdörfer, Sebastian and von Mammen, Sebastian and Latoschik, Marc Erich and Lugrin, Birgit}, journal = {Frontiers in Virtual Reality}, keywords = {oberdoerfer}, title = {Joyful Adventures and Frightening Places - Designing Emotion-Inducing Virtual Environments}, year = 2022 }
Krupitzer, C., Naber, J., Stauffert, J.-P., Mayer, J., Spielmann, J., Ehmann, P., Boci, N., Bürkle, M., Ho, A., Komorek, C., others: CortexVR: Immersive analysis and training of cognitive executive functions of soccer players using virtual reality and machine learning. Frontiers in Psychology. 13:754732, (2022).
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- [ URL ]
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Goal: This paper presents an immersive Virtual Reality (VR) system to analyze and train Executive Functions (EFs) of soccer players. EFs are important cognitive functions for athletes. They are a relevant quality that distinguishes amateurs from professionals. Method: The system is based on immersive technology, hence, the user interacts naturally and experiences a training session in a virtual world. The proposed system has a modular design supporting the extension of various so-called game modes. Game modes combine selected game mechanics with specific simulation content to target particular training aspects. The system architecture decouples selection/parameterization and analysis of training sessions via a coaching app from an Unity3D-based VR simulation core. Monitoring of user performance and progress is recorded by a database that sends the necessary feedback to the coaching app for analysis. Results: The system is tested for VR-critical performance criteria to reveal the usefulness of a new interaction paradigm in the cognitive training and analysis of EFs. Subjective ratings for overall usability show that the design as VR application enhances the user experience compared to a traditional desktop app; whereas the new, unfamiliar interaction paradigm does not negatively impact the effort for using the application. Conclusion: The system can provide immersive training of EF in a fully virtual environment, eliminating potential distraction. It further provides an easy-to-use analyzes tool to compare user but also an automatic, adaptive training mode.

@article{krupitzer2022cortexvr, abstract = {Goal: This paper presents an immersive Virtual Reality (VR) system to analyze and train Executive Functions (EFs) of soccer players. EFs are important cognitive functions for athletes. They are a relevant quality that distinguishes amateurs from professionals. Method: The system is based on immersive technology, hence, the user interacts naturally and experiences a training session in a virtual world. The proposed system has a modular design supporting the extension of various so-called game modes. Game modes combine selected game mechanics with specific simulation content to target particular training aspects. The system architecture decouples selection/parameterization and analysis of training sessions via a coaching app from an Unity3D-based VR simulation core. Monitoring of user performance and progress is recorded by a database that sends the necessary feedback to the coaching app for analysis. Results: The system is tested for VR-critical performance criteria to reveal the usefulness of a new interaction paradigm in the cognitive training and analysis of EFs. Subjective ratings for overall usability show that the design as VR application enhances the user experience compared to a traditional desktop app; whereas the new, unfamiliar interaction paradigm does not negatively impact the effort for using the application. Conclusion: The system can provide immersive training of EF in a fully virtual environment, eliminating potential distraction. It further provides an easy-to-use analyzes tool to compare user but also an automatic, adaptive training mode.}, author = {Krupitzer, Christian and Naber, Jens and Stauffert, Jan-Philipp and Mayer, Jan and Spielmann, Jan and Ehmann, Paul and Boci, Noel and Bürkle, Maurice and Ho, André and Komorek, Clemens and others}, journal = {Frontiers in Psychology}, keywords = {own}, publisher = {Frontiers}, title = {CortexVR: Immersive analysis and training of cognitive executive functions of soccer players using virtual reality and machine learning}, volume = {13:754732}, year = 2022 }
Bartl, A., Merz, C., Roth, D., Latoschik, M.E.: The Effects of Avatar and Environment Design on Embodiment, Presence, Activation, and Task Load in a Virtual Reality Exercise Application. IEEE International Symposium on Mixed and Augmented Reality (ISMAR) (2022).
- [ Abstract ]
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- [ URL ]
ABSTRACT The development of embodied Virtual Reality (VR) systems involves multiple central design choices. These design choices affect the user perception and therefore require thorough consideration. This article reports on two user studies investigating the influence of common design choices on relevant intermediate factors (sense of embodiment, presence, motivation, activation, and task load) in a VR application for physical exercises. The first study manipulated the avatar fidelity (abstract, partial body vs. anthropomorphic, full-body) and the environment (with vs. without mirror). The second study manipulated the avatar type (healthy vs. injured) and the environment type (beach vs. hospital) and, hence, the avatar-environment congruence. The full-body avatar significantly increased the sense of embodiment and decreased mental demand. Interestingly, the mirror did not influence the dependent variables. The injured avatar significantly increased the temporal demand. The beach environment significantly reduced the tense activation. On the beach, participants felt more present in the incongruent condition embodying the injured avatar.

@inproceedings{bartl2022effects, abstract = {ABSTRACT The development of embodied Virtual Reality (VR) systems involves multiple central design choices. These design choices affect the user perception and therefore require thorough consideration. This article reports on two user studies investigating the influence of common design choices on relevant intermediate factors (sense of embodiment, presence, motivation, activation, and task load) in a VR application for physical exercises. The first study manipulated the avatar fidelity (abstract, partial body vs. anthropomorphic, full-body) and the environment (with vs. without mirror). The second study manipulated the avatar type (healthy vs. injured) and the environment type (beach vs. hospital) and, hence, the avatar-environment congruence. The full-body avatar significantly increased the sense of embodiment and decreased mental demand. Interestingly, the mirror did not influence the dependent variables. The injured avatar significantly increased the temporal demand. The beach environment significantly reduced the tense activation. On the beach, participants felt more present in the incongruent condition embodying the injured avatar.}, author = {Bartl, Andrea and Merz, Christian and Roth, Daniel and Latoschik, Marc Erich}, booktitle = {IEEE International Symposium on Mixed and Augmented Reality (ISMAR)}, keywords = {myown}, title = {The Effects of Avatar and Environment Design on Embodiment, Presence, Activation, and Task Load in a Virtual Reality Exercise Application}, year = 2022 }
Herud, K., Baumeister, J., Sabuncu, O., Schaub, T.: Conflict Handling in Product Configuration using Answer Set Programming. ICLP Workshop Answer Set Programming and Other Computing Paradigms (2022).
- [ BibTeX ]
- [ URL ]
@inproceedings{hbs:22, author = {Herud, Konstantin and Baumeister, Joachim and Sabuncu, Orkunt and Schaub, Torsten}, booktitle = {ICLP Workshop Answer Set Programming and Other Computing Paradigms}, keywords = {myown}, title = {Conflict Handling in Product Configuration using Answer Set Programming}, year = 2022 }
Heil, S., Kopp, K., Zehe, A., Kobs, K., Hotho, A.: {LSX} team5 at {S}em{E}val-2022 Task 8: Multilingual News Article Similarity Assessment based on Word- and Sentence Mover{’}s Distance. Proceedings of the 16th International Workshop on Semantic Evaluation (SemEval-2022). S. 1190–1195. Association for Computational Linguistics, Seattle, United States (2022).
- [ Abstract ]
- [ BibTeX ]
- [ URL ]
This paper introduces our submission for the SemEval 2022 Task 8: Multilingual News Article Similarity. The task of the competition consisted of the development of a model, capable of determining the similarity between pairs of multilingual news articles. To address this challenge, we evaluated the Word Mover{'}s Distance in conjunction with word embeddings from ConceptNet Numberbatch and term frequencies of WorldLex, as well the Sentence Mover{'}s Distance based on sentence embeddings generated by pretrained transformer models of Sentence-BERT. To facilitate the comparison of multilingual articles with Sentence-BERT models, we deployed a Neural Machine Translation system. All our models achieve stable results in multilingual similarity estimation without learning parameters.

@inproceedings{heil2022lsxteam5, abstract = {This paper introduces our submission for the SemEval 2022 Task 8: Multilingual News Article Similarity. The task of the competition consisted of the development of a model, capable of determining the similarity between pairs of multilingual news articles. To address this challenge, we evaluated the Word Mover{'}s Distance in conjunction with word embeddings from ConceptNet Numberbatch and term frequencies of WorldLex, as well the Sentence Mover{'}s Distance based on sentence embeddings generated by pretrained transformer models of Sentence-BERT. To facilitate the comparison of multilingual articles with Sentence-BERT models, we deployed a Neural Machine Translation system. All our models achieve stable results in multilingual similarity estimation without learning parameters.}, address = {Seattle, United States}, author = {Heil, Stefan and Kopp, Karina and Zehe, Albin and Kobs, Konstantin and Hotho, Andreas}, booktitle = {Proceedings of the 16th International Workshop on Semantic Evaluation (SemEval-2022)}, keywords = {similarity}, month = {jul}, pages = {1190–1195}, publisher = {Association for Computational Linguistics}, title = {{LSX} team5 at {S}em{E}val-2022 Task 8: Multilingual News Article Similarity Assessment based on Word- and Sentence Mover{'}s Distance}, year = 2022 }
Riedmann, A., Schaper, P., Jakob, B., Lugrin, B.: A Theory Based Adaptive Pedagogical Agent in a Reading App for Primary Students - A User Study. In: Crossley, S. und Popescu, E. (hrsg.) Intelligent Tutoring Systems. ITS 2022. Lecture Notes in Computer Science. Springer (2022).
- [ BibTeX ]
- [ DOI ]
@inproceedings{riedmann2022theory, author = {Riedmann, Anna and Schaper, Philipp and Jakob, Benedikt and Lugrin, Birgit}, booktitle = {Intelligent Tutoring Systems. ITS 2022. Lecture Notes in Computer Science}, editor = {Crossley, S. and Popescu, E.}, keywords = {schaper}, publisher = {Springer}, title = {A Theory Based Adaptive Pedagogical Agent in a Reading App for Primary Students - A User Study}, volume = 13284, year = 2022 }
Tritscher, J., Gwinner, F., Schlör, D., Krause, A., Hotho, A.: Open ERP System Data For Occupational Fraud Detection. arxiv. (2022).
- [ BibTeX ]
- [ URL ]
@article{tritscher2022erpData, author = {Tritscher, Julian and Gwinner, Fabian and Schlör, Daniel and Krause, Anna and Hotho, Andreas}, journal = {arxiv}, keywords = {myown}, title = {Open ERP System Data For Occupational Fraud Detection}, year = 2022 }
Babu, S.K., von Mammen, S.: Learning Classifier Systems as Recommender Systems. Lifelike Computing Systems Workshop LIFELIKE 2022 (2022).
- [ Abstract ]
- [ BibTeX ]
- [ URL ]
A multitude of software domains, ranging from e-commerce services to personal digital assistants, rely on recommender systems (RS) to enhance their performance and customer experience. There are several established approaches to RS, including algorithms, namely, collaborative filtering, content based filtering, and various hybrid systems that use different verticals of data, such as the user’s preferences, the metadata of items to be suggested, etc., to generate recommendations. Contrary to those, we adopt a classifier system to benefit from its rule-based knowledge representation and interwoven learning mechanisms. In this paper, we present our approach and elaborate on its potential use to flexibly and effectively guide a user through the application of an authoring platform.

@inproceedings{babu2022learning, abstract = {A multitude of software domains, ranging from e-commerce services to personal digital assistants, rely on recommender systems (RS) to enhance their performance and customer experience. There are several established approaches to RS, including algorithms, namely, collaborative filtering, content based filtering, and various hybrid systems that use different verticals of data, such as the user’s preferences, the metadata of items to be suggested, etc., to generate recommendations. Contrary to those, we adopt a classifier system to benefit from its rule-based knowledge representation and interwoven learning mechanisms. In this paper, we present our approach and elaborate on its potential use to flexibly and effectively guide a user through the application of an authoring platform.}, author = {Babu, Sooraj K and von Mammen, Sebastian}, booktitle = {Lifelike Computing Systems Workshop LIFELIKE 2022}, keywords = {via-vr}, title = {Learning Classifier Systems as Recommender Systems}, year = 2022 }
Hofmann, S., M{\"u}ller, A., von Mammen, S.: Interactive Hemodynamic Simulation Model of a Cross-scale Cardiovascular System. ANNSIM 22. Society for Modeling & Simulation International (SCS) (2022).
- [ BibTeX ]
- [ URL ]
@inproceedings{Hofmann2022INTERACTIVEHS, author = {Hofmann, Sarah and M{\"u}ller, Andreas and von Mammen, Sebastian}, booktitle = {ANNSIM 22}, keywords = {myown}, publisher = {Society for Modeling & Simulation International (SCS)}, title = {Interactive Hemodynamic Simulation Model of a Cross-scale Cardiovascular System}, year = 2022 }
Hofmann, S., Seeger, M., Rogge-Pott, H., Mammen, S. von: {Real-Time Music-Driven Movie Design Framework}. In: Ronfard, R. und Wu, H.-Y. (hrsg.) Workshop on Intelligent Cinematography and Editing. The Eurographics Association (2022).
- [ BibTeX ]
- [ URL ]
- [ DOI ]
@inproceedings{10.2312:wiced.20221052, author = {Hofmann, Sarah and Seeger, Maximilian and Rogge-Pott, Henning and Mammen, Sebastian von}, booktitle = {Workshop on Intelligent Cinematography and Editing}, editor = {Ronfard, Rémi and Wu, Hui-Yin}, keywords = {myown}, publisher = {The Eurographics Association}, title = {{Real-Time Music-Driven Movie Design Framework}}, year = 2022 }
Grigorjew, A., Metzger, F., Hoßfeld, T., Specht, J., Götz, F.-J., Chen, F., Schmitt, J.: Constant Delay Switching: Asynchronous Traffic Shaping with Jitter Control. 2022 IFIP Networking Conference (IFIP Networking) (2022).
- [ Abstract ]
- [ BibTeX ]
Recent developments in the Time Sensitive Networking (TSN) group have put forth a number of mechanisms to improve deterministic latency in layer 2 switches. Their shaping approaches differ with respect to prerequisites, flexibility, maximum latency, and latency variation (jitter). Asynchronous solutions provide flexibility in dynamic scenarios, but Credit-Based Shaping (CBS) and Asynchronous Traffic Shaping (ATS) come with a high latency variance, as the minimum latency is not affected by them. Some applications in industrial and automotive use cases require low jitter while trying to avoid a dependency on time synchronization, and even TSN's redundancy mechanism benefits from a lower latency variance. This work is bridging the gap between low-jitter transmission requirements and asynchronous shaping mechanisms. In this paper, the application of a stateless Asynchronous Constant Delay Shaper (ACDS) is discussed. It collects the queuing duration from the previous bridge to delay each frame for the remaining time such that a constant per-hop delay for each frame is achieved. The discussion includes the prerequisites, the mechanism itself, and its technical complexity, as well as a formal analysis of its guaranteed latency by proving its relation to a token-bucket based ATS. Further, two extensions are discussed, and an evaluation shows the applicability of ACDS by comparing its jitter to ATS in a frame-level simulation.

@inproceedings{info3-inproceedings-2022-15, abstract = {Recent developments in the Time Sensitive Networking (TSN) group have put forth a number of mechanisms to improve deterministic latency in layer 2 switches. Their shaping approaches differ with respect to prerequisites, flexibility, maximum latency, and latency variation (jitter). Asynchronous solutions provide flexibility in dynamic scenarios, but Credit-Based Shaping (CBS) and Asynchronous Traffic Shaping (ATS) come with a high latency variance, as the minimum latency is not affected by them. Some applications in industrial and automotive use cases require low jitter while trying to avoid a dependency on time synchronization, and even TSN's redundancy mechanism benefits from a lower latency variance. This work is bridging the gap between low-jitter transmission requirements and asynchronous shaping mechanisms. In this paper, the application of a stateless Asynchronous Constant Delay Shaper (ACDS) is discussed. It collects the queuing duration from the previous bridge to delay each frame for the remaining time such that a constant per-hop delay for each frame is achieved. The discussion includes the prerequisites, the mechanism itself, and its technical complexity, as well as a formal analysis of its guaranteed latency by proving its relation to a token-bucket based ATS. Further, two extensions are discussed, and an evaluation shows the applicability of ACDS by comparing its jitter to ATS in a frame-level simulation.}, author = {Grigorjew, Alexej and Metzger, Florian and Hoßfeld, Tobias and Specht, Johannes and Götz, Franz-Josef and Chen, Feng and Schmitt, Jürgen}, booktitle = {2022 IFIP Networking Conference (IFIP Networking)}, keywords = {kosinu5}, month = 6, title = {Constant Delay Switching: Asynchronous Traffic Shaping with Jitter Control}, year = 2022 }
Grigorjew, A., Diederich, P., Hoßfeld, T., Kellerer, W.: Affordable Measurement Setups for Networking Device Latency with Sub-Microsecond Accuracy. WueWoWAS’22 KuVS Fachgespraech - Wuerzburg Workshop on Next-Generation Communication Networks (2022).
- [ Abstract ]
- [ BibTeX ]
This document presents a networking latency measurement setup that focuses on affordability and universal applicability, and can provide sub-microsecond accuracy. It explains the prerequisites, hardware choices, and considerations to respect during measurement. In addition, it discusses the necessity for exhaustive latency measurements when dealing with high availability and low latency requirements. Preliminary results show that the accuracy is within 0.02 microseconds when used with the Intel I350-T2 network adapter.

@inproceedings{info3-inproceedings-2022-14, abstract = {This document presents a networking latency measurement setup that focuses on affordability and universal applicability, and can provide sub-microsecond accuracy. It explains the prerequisites, hardware choices, and considerations to respect during measurement. In addition, it discusses the necessity for exhaustive latency measurements when dealing with high availability and low latency requirements. Preliminary results show that the accuracy is within 0.02 microseconds when used with the Intel I350-T2 network adapter.}, author = {Grigorjew, Alexej and Diederich, Philip and Hoßfeld, Tobias and Kellerer, Wolfgang}, booktitle = {WueWoWAS'22 KuVS Fachgespraech - Wuerzburg Workshop on Next-Generation Communication Networks}, keywords = {appaware2}, month = 7, title = {Affordable Measurement Setups for Networking Device Latency with Sub-Microsecond Accuracy}, year = 2022 }
Hein, R.M., Latoschik, M.E., Wienrich, C.: Inter- and Transcultural Learning in Social Virtual Reality: A Proposal for an Inter- and Transcultural Virtual Object Database to be Used in the Implementation, Reflection, and Evaluation of Virtual Encounters. Multimodal Technologies and Interaction. 6, 50 (2022).
- [ Abstract ]
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- [ URL ]
- [ DOI ]
Visual stimuli are frequently used to improve memory, language learning or perception, and understanding of metacognitive processes. However, in virtual reality (VR), there are few systematically and empirically derived databases. This paper proposes the first collection of virtual objects based on empirical evaluation for inter-and transcultural encounters between English- and German-speaking learners. We used explicit and implicit measurement methods to identify cultural associations and the degree of stereotypical perception for each virtual stimuli (n = 293) through two online studies, including native German and English-speaking participants. The analysis resulted in a final well-describable database of 128 objects (called InteractionSuitcase). In future applications, the objects can be used as a great interaction or conversation asset and behavioral measurement tool in social VR applications, especially in the field of foreign language education. For example, encounters can use the objects to describe their culture, or teachers can intuitively assess stereotyped attitudes of the encounters.

@article{mti6070050, abstract = {Visual stimuli are frequently used to improve memory, language learning or perception, and understanding of metacognitive processes. However, in virtual reality (VR), there are few systematically and empirically derived databases. This paper proposes the first collection of virtual objects based on empirical evaluation for inter-and transcultural encounters between English- and German-speaking learners. We used explicit and implicit measurement methods to identify cultural associations and the degree of stereotypical perception for each virtual stimuli (n = 293) through two online studies, including native German and English-speaking participants. The analysis resulted in a final well-describable database of 128 objects (called InteractionSuitcase). In future applications, the objects can be used as a great interaction or conversation asset and behavioral measurement tool in social VR applications, especially in the field of foreign language education. For example, encounters can use the objects to describe their culture, or teachers can intuitively assess stereotyped attitudes of the encounters.}, author = {Hein, Rebecca M. and Latoschik, Marc Erich and Wienrich, Carolin}, editor = {{Mark Billinghurst, Fotis Liarokapis}, Lars Erik Holmquist and Su, Mu-Chun}, journal = {Multimodal Technologies and Interaction}, keywords = {rhein}, number = 7, pages = 50, title = {Inter- and Transcultural Learning in Social Virtual Reality: A Proposal for an Inter- and Transcultural Virtual Object Database to be Used in the Implementation, Reflection, and Evaluation of Virtual Encounters}, volume = 6, year = 2022 }
Donnermann, M., Schaper, P., Lugrin, B.: Social Robots in Applied Settings: A Long-Term Study on Adaptive Robotic Tutors in Higher Education. Frontiers in Robotics and AI. 9, (2022).
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@article{Donnermann_2022, author = {Donnermann, Melissa and Schaper, Philipp and Lugrin, Birgit}, journal = {Frontiers in Robotics and AI}, keywords = {schaper}, publisher = {Frontiers Media SA}, title = {Social Robots in Applied Settings: A Long-Term Study on Adaptive Robotic Tutors in Higher Education}, volume = 9, year = 2022 }
Davidson, P., Steininger, M., Huhn, A., Krause, A., Hotho, A.: Semi-unsupervised Learning for Time Series Classification. Milets@KDD. (2022).
- [ Abstract ]
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Time series are ubiquitous and therefore inherently hard to analyze and ultimately to label or cluster. With the rise of the Internet of Things (IoT) and its smart devices, data is collected in large amounts any given second. The collected data is rich in information, as one can detect accidents (e.g. cars) in real time, or assess injury/sickness over a given time span (e.g. health devices). Due to its chaotic nature and massive amounts of datapoints, timeseries are hard to label manually. Furthermore new classes within the data could emerge over time (contrary to e.g. handwritten digits), which would require relabeling the data. In this paper we present SuSL4TS, a deep generative Gaussian mixture model for semi-unsupervised learning, to classify time series data. With our approach we can alleviate manual labeling steps, since we can detect sparsely labeled classes (semi-supervised) and identify emerging classes hidden in the data (unsupervised). We demonstrate the efficacy of our approach with established time series classification datasets from different domains.

@article{davidson2022semiunsupervised, abstract = {Time series are ubiquitous and therefore inherently hard to analyze and ultimately to label or cluster. With the rise of the Internet of Things (IoT) and its smart devices, data is collected in large amounts any given second. The collected data is rich in information, as one can detect accidents (e.g. cars) in real time, or assess injury/sickness over a given time span (e.g. health devices). Due to its chaotic nature and massive amounts of datapoints, timeseries are hard to label manually. Furthermore new classes within the data could emerge over time (contrary to e.g. handwritten digits), which would require relabeling the data. In this paper we present SuSL4TS, a deep generative Gaussian mixture model for semi-unsupervised learning, to classify time series data. With our approach we can alleviate manual labeling steps, since we can detect sparsely labeled classes (semi-supervised) and identify emerging classes hidden in the data (unsupervised). We demonstrate the efficacy of our approach with established time series classification datasets from different domains.}, author = {Davidson, Padraig and Steininger, Michael and Huhn, André and Krause, Anna and Hotho, Andreas}, journal = {Milets@KDD}, keywords = {timeseries}, publisher = {arXiv}, title = {Semi-unsupervised Learning for Time Series Classification}, year = 2022 }
Chaplick, S., Kindermann, P., Klawitter, J., Rutter, I., Wolff, A.: Morphing Rectangular Duals. In: Angelini, P. und von Hanxleden, R. (hrsg.) Proc. 30th Int. Symp. Graph Drawing \& Network Vis. (GD’22). Springer-Verlag (2022).
- [ BibTeX ]
@inproceedings{ckkrw-mrd-GD22, author = {Chaplick, Steven and Kindermann, Philipp and Klawitter, Jonathan and Rutter, Ignaz and Wolff, Alexander}, booktitle = {Proc. 30th Int. Symp. Graph Drawing \& Network Vis. (GD'22)}, editor = {Angelini, Patrizio and von Hanxleden, Reinhard}, keywords = {myown}, publisher = {Springer-Verlag}, series = {Lecture Notes in Computer Science}, title = {Morphing Rectangular Duals}, year = 2022 }
Glémarec, Y., Lugrin, J.-L., Bosser, A.-G., Buche, C., Latoschik, M.E.: Controlling the STAGE: A High-Level Control System for Virtual Audiences In Virtual Reality. Frontiers in Virtual Reality – Virtual Reality and Human Behaviour. (2022).
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This article presents a novel method for controlling a virtual audience system (VAS) in Virtual Reality (VR) application, called STAGE, which has been originally designed for supervised public speaking training in university seminars dedicated to the preparation and delivery of scientific talks. We are interested in creating pedagogical \emph{narratives}: narratives encompass affective phenomena and rather than organizing events changing the course of a training scenario, pedagogical plans using our system focus on organizing the affects it arouses for the trainees. Efficiently controlling a virtual audience towards a specific training objective while evaluating the speaker's performance presents a challenge for a seminar instructor: the high level of cognitive and physical demands required to be able to control the virtual audience, whilst evaluating speaker's performance, adjusting and allowing it to quickly react to the user’s behaviors and interactions. It is indeed a critical limitation of a number of existing systems that they rely on a Wizard of Oz approach, where the tutor drives the audience in reaction to the user’s performance. We address this problem by integrating with a VAS a high-level control component for tutors, which allows using predefined audience behavior rules, defining custom ones, as well as intervening during run-time for finer control of the unfolding of the pedagogical plan. At its core, this component offers a tool to program, select, modify and monitor interactive training narratives using a high-level representation. The STAGE offers the following features: i) a high-level API to program pedagogical narratives focusing on a specific public speaking situation and training objectives, ii) an interactive visualization interface iii) computation and visualization of user metrics, iv) a semi-autonomous virtual audience composed of virtual spectators with automatic reactions to the speaker and surrounding spectators while following the pedagogical plan V) and the possibility for the instructor to embody a virtual spectator to ask questions or guide the speaker from within the Virtual Environment. We present here the design, implementation of the tutoring system and its integration in STAGE, and discuss its reception by end-users.

@article{glemarec2022controlling, abstract = {This article presents a novel method for controlling a virtual audience system (VAS) in Virtual Reality (VR) application, called STAGE, which has been originally designed for supervised public speaking training in university seminars dedicated to the preparation and delivery of scientific talks. We are interested in creating pedagogical \emph{narratives}: narratives encompass affective phenomena and rather than organizing events changing the course of a training scenario, pedagogical plans using our system focus on organizing the affects it arouses for the trainees. Efficiently controlling a virtual audience towards a specific training objective while evaluating the speaker's performance presents a challenge for a seminar instructor: the high level of cognitive and physical demands required to be able to control the virtual audience, whilst evaluating speaker's performance, adjusting and allowing it to quickly react to the user’s behaviors and interactions. It is indeed a critical limitation of a number of existing systems that they rely on a Wizard of Oz approach, where the tutor drives the audience in reaction to the user’s performance. We address this problem by integrating with a VAS a high-level control component for tutors, which allows using predefined audience behavior rules, defining custom ones, as well as intervening during run-time for finer control of the unfolding of the pedagogical plan. At its core, this component offers a tool to program, select, modify and monitor interactive training narratives using a high-level representation. The STAGE offers the following features: i) a high-level API to program pedagogical narratives focusing on a specific public speaking situation and training objectives, ii) an interactive visualization interface iii) computation and visualization of user metrics, iv) a semi-autonomous virtual audience composed of virtual spectators with automatic reactions to the speaker and surrounding spectators while following the pedagogical plan V) and the possibility for the instructor to embody a virtual spectator to ask questions or guide the speaker from within the Virtual Environment. We present here the design, implementation of the tutoring system and its integration in STAGE, and discuss its reception by end-users.}, author = {Glémarec, Yann and Lugrin, Jean-Luc and Bosser, Anne-Gwenn and Buche, Cedric and Latoschik, Marc Erich}, journal = {Frontiers in Virtual Reality – Virtual Reality and Human Behaviour}, keywords = {myown}, title = {Controlling the STAGE: A High-Level Control System for Virtual Audiences In Virtual Reality}, year = 2022 }
Klawitter, J., Klemz, B., Klesen, F., Kobourov, S., Kryven, M., Wolff, A., Zink, J.: Universal Lower Bounds on the Segment Number of Some Classes of Planar Graphs. In: {Di Giacomo}, E. und Montecchiani, F. (hrsg.) Proc. 38th Europ. Workshop Comput. Geom. (EuroCG’22). S. 53:1–7 (2022).
- [ BibTeX ]
@inproceedings{kkkkkwz-ulbsn-EuroCG22, author = {Klawitter, Jonathan and Klemz, Boris and Klesen, Felix and Kobourov, Stephen and Kryven, Myroslav and Wolff, Alexander and Zink, Johannes}, booktitle = {Proc. 38th Europ. Workshop Comput. Geom. (EuroCG'22)}, editor = {{Di Giacomo}, Emilio and Montecchiani, Fabrizio}, keywords = {myown}, pages = {53:1–7}, title = {Universal Lower Bounds on the Segment Number of Some Classes of Planar Graphs}, year = 2022 }
Döllinger, N., Wolf, E., Mal, D., Wenninger, S., Botsch, M., Latoschik, M.E., Wienrich, C.: Resize Me! Exploring the User Experience of Embodied Realistic Modulatable Avatars for Body Image Intervention in Virtual Reality. Frontiers in Virtual Reality. 3, (2022).
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Obesity is a serious disease that can affect both physical and psychological well-being. Due to weight stigmatization, many affected individuals suffer from body image disturbances whereby they perceive their body in a distorted way, evaluate it negatively, or neglect it. Beyond established interventions such as mirror exposure, recent advancements aim to complement body image treatments by the embodiment of visually altered virtual bodies in virtual reality (VR). We present a high-fidelity prototype of an advanced VR system that allows users to embody a rapidly generated personalized, photorealistic avatar and to realistically modulate its body weight in real-time within a carefully designed virtual environment. In a formative multi-method approach, a total of 12 participants rated the general user experience (UX) of our system during body scan and VR experience using semi-structured qualitative interviews and multiple quantitative UX measures. Using body weight modification tasks, we further compared three different interaction methods for real-time body weight modification and measured our system's impact on the body image relevant measures body awareness and body weight perception. From the feedback received, demonstrating an already solid UX of our overall system and providing constructive input for further improvement, we derived a set of design guidelines to guide future development and evaluation processes of systems supporting body image interventions.

@article{dollinger2022resizeme, abstract = {Obesity is a serious disease that can affect both physical and psychological well-being. Due to weight stigmatization, many affected individuals suffer from body image disturbances whereby they perceive their body in a distorted way, evaluate it negatively, or neglect it. Beyond established interventions such as mirror exposure, recent advancements aim to complement body image treatments by the embodiment of visually altered virtual bodies in virtual reality (VR). We present a high-fidelity prototype of an advanced VR system that allows users to embody a rapidly generated personalized, photorealistic avatar and to realistically modulate its body weight in real-time within a carefully designed virtual environment. In a formative multi-method approach, a total of 12 participants rated the general user experience (UX) of our system during body scan and VR experience using semi-structured qualitative interviews and multiple quantitative UX measures. Using body weight modification tasks, we further compared three different interaction methods for real-time body weight modification and measured our system's impact on the body image relevant measures body awareness and body weight perception. From the feedback received, demonstrating an already solid UX of our overall system and providing constructive input for further improvement, we derived a set of design guidelines to guide future development and evaluation processes of systems supporting body image interventions.}, author = {Döllinger, Nina and Wolf, Erik and Mal, David and Wenninger, Stephan and Botsch, Mario and Latoschik, Marc Erich and Wienrich, Carolin}, journal = {Frontiers in Virtual Reality}, keywords = {vitras}, title = {Resize Me! Exploring the User Experience of Embodied Realistic Modulatable Avatars for Body Image Intervention in Virtual Reality}, volume = 3, year = 2022 }
Wienrich, C., Fries, L., Latoschik, M.E.: Remote at Court – Challenges and Solutions of Video Conferencing in the Judicial System. Proceedings 25th HCI International Conference. S. 82–106. Springer (2022).
- [ BibTeX ]
@inproceedings{wienrich2022remote, author = {Wienrich, Carolin and Fries, Lennart and Latoschik, Marc Erich}, booktitle = {Proceedings 25th HCI International Conference}, keywords = {myown}, pages = {82-106}, publisher = {Springer}, title = {Remote at Court – Challenges and Solutions of Video Conferencing in the Judicial System}, volume = {Design, Operation and Evaluation of Mobile Communications}, year = 2022 }
Brübach, L., Westermeier, F., Wienrich, C., Latoschik, M.E.: Breaking Plausibility Without Breaking Presence - Evidence For The Multi-Layer Nature Of Plausibility. IEEE Transactions on Visualization and Computer Graphics. 1–1 (2022).
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A novel theoretical model recently introduced coherence and plausibility as the essential conditions of XR experiences, challenging contemporary presence-oriented concepts. This article reports on two experiments validating this model, which assumes coherence activation on three layers (cognition, perception, and sensation) as the potential sources leading to a condition of plausibility and from there to other XR qualia such as presence or body ownership. The experiments introduce and utilize breaks in plausibility (in analogy to breaks in presence): We induce incoherence on the perceptual and the cognitive layer simultaneously by a simulation of object behaviors that do not conform to the laws of physics, i.e., gravity. We show that this manipulation breaks plausibility and hence confirm that it results in the desired effects in the theorized condition space but that the breaks in plausibility did not affect presence. In addition, we show that a cognitive manipulation by a storyline framing is too weak to successfully counteract the strong bottom-up inconsistencies. Both results are in line with the predictions of the recently introduced three-layer model of coherence and plausibility, which incorporates well-known top-down and bottom-up rivalries and its theorized increased independence between plausibility and presence.

@article{9714117, abstract = {A novel theoretical model recently introduced coherence and plausibility as the essential conditions of XR experiences, challenging contemporary presence-oriented concepts. This article reports on two experiments validating this model, which assumes coherence activation on three layers (cognition, perception, and sensation) as the potential sources leading to a condition of plausibility and from there to other XR qualia such as presence or body ownership. The experiments introduce and utilize breaks in plausibility (in analogy to breaks in presence): We induce incoherence on the perceptual and the cognitive layer simultaneously by a simulation of object behaviors that do not conform to the laws of physics, i.e., gravity. We show that this manipulation breaks plausibility and hence confirm that it results in the desired effects in the theorized condition space but that the breaks in plausibility did not affect presence. In addition, we show that a cognitive manipulation by a storyline framing is too weak to successfully counteract the strong bottom-up inconsistencies. Both results are in line with the predictions of the recently introduced three-layer model of coherence and plausibility, which incorporates well-known top-down and bottom-up rivalries and its theorized increased independence between plausibility and presence.}, author = {Brübach, Larissa and Westermeier, Franziska and Wienrich, Carolin and Latoschik, Marc Erich}, journal = {IEEE Transactions on Visualization and Computer Graphics}, keywords = {myown}, note = {IEEE VR Best Journal Paper Nominee 🏆}, pages = {1-1}, title = {Breaking Plausibility Without Breaking Presence - Evidence For The Multi-Layer Nature Of Plausibility}, year = 2022 }
Seibt, S., von Ramon Lipinski, B., Latoschik, M.E.: Dense Feature Matching based on Homographic Decomposition. IEEE Access. X, 1–1 (2022).
- [ Abstract ]
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- [ URL ]
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Finding robust and accurate feature matches is a fundamental problem in computer vision. However, incorrect correspondences and suboptimal matching accuracies lead to significant challenges for many real-world applications. In conventional feature matching, corresponding features in an image pair are greedily searched using their descriptor distance. The resulting matching set is then typically used as input for geometric model fitting methods to find an appropriate fundamental matrix and filter out incorrect matches. Unfortunately, this basic approach cannot solve all practical problems, such as fundamental matrix degeneration, matching ambiguities caused by repeated patterns and rejection of initially mismatched features without further reconsideration. In this paper we introduce a novel matching pipeline, which addresses all of the aforementioned challenges at once: First, we perform iterative rematching to give mismatched feature points a further chance for being considered in later processing steps. Thereby, we are searching for inliers that exhibit the same homographic transformation per iteration. The resulting homographic decomposition is used for refining matches, occlusion detection (e.g. due to parallaxes) and extrapolation of additional features in critical image areas. Furthermore, Delaunay triangulation of the matching set is utilized to minimize the repeated pattern problem and to implement focused matching. Doing so, enables us to further increase matching quality by concentrating on local image areas, defined by the triangular mesh. We present and discuss experimental results with multiple real-world matching datasets. Our contributions, besides improving matching recall and precision for image processing applications in general, also relate to use cases in image-based computer graphics.

@article{seibt2022dense, abstract = {Finding robust and accurate feature matches is a fundamental problem in computer vision. However, incorrect correspondences and suboptimal matching accuracies lead to significant challenges for many real-world applications. In conventional feature matching, corresponding features in an image pair are greedily searched using their descriptor distance. The resulting matching set is then typically used as input for geometric model fitting methods to find an appropriate fundamental matrix and filter out incorrect matches. Unfortunately, this basic approach cannot solve all practical problems, such as fundamental matrix degeneration, matching ambiguities caused by repeated patterns and rejection of initially mismatched features without further reconsideration. In this paper we introduce a novel matching pipeline, which addresses all of the aforementioned challenges at once: First, we perform iterative rematching to give mismatched feature points a further chance for being considered in later processing steps. Thereby, we are searching for inliers that exhibit the same homographic transformation per iteration. The resulting homographic decomposition is used for refining matches, occlusion detection (e.g. due to parallaxes) and extrapolation of additional features in critical image areas. Furthermore, Delaunay triangulation of the matching set is utilized to minimize the repeated pattern problem and to implement focused matching. Doing so, enables us to further increase matching quality by concentrating on local image areas, defined by the triangular mesh. We present and discuss experimental results with multiple real-world matching datasets. Our contributions, besides improving matching recall and precision for image processing applications in general, also relate to use cases in image-based computer graphics.}, author = {Seibt, Simon and von Ramon Lipinski, Bartosz and Latoschik, March Erich}, journal = {IEEE Access}, keywords = {myown}, pages = {1-1}, title = {Dense Feature Matching based on Homographic Decomposition}, volume = {X}, year = 2022 }
Birnstiel, S., Oberdörfer, S., Latoschik, M.E.: Stay Safe! Safety Precautions for Walking on a Conventional Treadmill in VR. Proceedings of the 29th IEEE Conference on Virtual Reality and 3D User Interfaces Abstracts and Workshops (VR ’22). 732–733 (2022).
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@article{birnstiel2022safety, author = {Birnstiel, Sandra and Oberdörfer, Sebastian and Latoschik, Marc Erich}, journal = {Proceedings of the 29th IEEE Conference on Virtual Reality and 3D User Interfaces Abstracts and Workshops (VR '22)}, keywords = {oberdoerfer}, pages = {732-733}, title = {Stay Safe! Safety Precautions for Walking on a Conventional Treadmill in VR}, year = 2022 }
Mal, D., Wolf, E., Döllinger, N., Botsch, M., Wienrich, C., Latoschik, M.E.: Virtual Human Coherence and Plausibility – Towards a Validated Scale. Proceedings of the 29th IEEE Conference on Virtual Reality and 3D User Interfaces Abstracts and Workshops (VR ’22). S. 788–789 (2022).
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- [ BibTeX ]
- [ URL ]
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Virtual humans contribute to users’ state of plausibility in various XR applications. We present the development and preliminary evaluation of a self-assessment questionnaire to quantify virtual human’s plausibility in virtual environments based on eleven concise items. A principal component analysis of 650 appraisals collected in an online survey revealed two highly reliable components within the items. We interpret the components as possible factors, i.e., appearance and behavior plausibility and match to the virtual environment, and propose future work aiming towards a standardized virtual human plausibility scale by validating the structure and sensitivity of both sub-components in XR environments.

@inproceedings{mal2022virtual, abstract = {Virtual humans contribute to users’ state of plausibility in various XR applications. We present the development and preliminary evaluation of a self-assessment questionnaire to quantify virtual human’s plausibility in virtual environments based on eleven concise items. A principal component analysis of 650 appraisals collected in an online survey revealed two highly reliable components within the items. We interpret the components as possible factors, i.e., appearance and behavior plausibility and match to the virtual environment, and propose future work aiming towards a standardized virtual human plausibility scale by validating the structure and sensitivity of both sub-components in XR environments.}, author = {Mal, David and Wolf, Erik and Döllinger, Nina and Botsch, Mario and Wienrich, Carolin and Latoschik, Marc Erich}, booktitle = {Proceedings of the 29th IEEE Conference on Virtual Reality and 3D User Interfaces Abstracts and Workshops (VR '22)}, keywords = {vitras}, pages = {788-789}, title = {Virtual Human Coherence and Plausibility – Towards a Validated Scale}, year = 2022 }
Balko, M., Chaplick, S., Gupta, S., Hoffmann, M., Valtr, P., Wolff, A.: Bounding and Computing Obstacle Numbers of Graphs. In: Chechik, S., Navarro, G., Rotenberg, E., und Herman, G. (hrsg.) Proc. 30th Europ. Symp. Algorithms (ESA’22). S. 11:1–11:13. Schloss Dagstuhl~-- Leibniz-Zentrum f{\"u}r Informatik (2022).
- [ BibTeX ]
- [ DOI ]
@inproceedings{bcghvw-bcong-ESA22, author = {Balko, Martin and Chaplick, Steven and Gupta, Siddharth and Hoffmann, Michael and Valtr, Pavel and Wolff, Alexander}, booktitle = {Proc. 30th Europ. Symp. Algorithms (ESA'22)}, editor = {Chechik, Shiri and Navarro, Gonzalo and Rotenberg, Eva and Herman, Grzegorz}, keywords = {myown}, pages = {11:1–11:13}, publisher = {Schloss Dagstuhl – Leibniz-Zentrum f{\"u}r Informatik}, series = {LIPIcs}, title = {Bounding and Computing Obstacle Numbers of Graphs}, volume = 244, year = 2022 }
Schmid, K., Knote, A., Mück, A., Pfeiffer, K., von Mammen, S., Fischer, S.C.: Interactive, Visual Simulation of a Spatio-Temporal Model of Gas Exchange in the Human Alveolus. Frontiers in Bioinformatics. 1, (2022).
- [ Abstract ]
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In interdisciplinary fields such as systems biology, good communication between experimentalists and theorists is crucial for the success of a project. Theoretical modeling in physiology usually describes complex systems with many interdependencies. On one hand, these models have to be grounded on experimental data. On the other hand, experimenters must be able to understand the interdependent complexities of the theoretical model in order to interpret the model’s results in the physiological context. We promote interactive, visual simulations as an engaging way to present theoretical models in physiology and to make complex processes tangible. Based on a requirements analysis, we developed a new model for gas exchange in the human alveolus in combination with an interactive simulation software named Alvin. Alvin exceeds the current standard with its spatio-temporal resolution and a combination of visual and quantitative feedback. In Alvin, the course of the simulation can be traced in a three-dimensional rendering of an alveolus and dynamic plots. The user can interact by configuring essential model parameters. Alvin allows to run and compare multiple simulation instances simultaneously. We exemplified the use of Alvin for research by identifying unknown dependencies in published experimental data. Employing a detailed questionnaire, we showed the benefits of Alvin for education. We postulate that interactive, visual simulation of theoretical models, as we have implemented with Alvin on respiratory processes in the alveolus, can be of great help for communication between specialists and thereby advancing research.

@article{10.3389/fbinf.2021.774300, abstract = {In interdisciplinary fields such as systems biology, good communication between experimentalists and theorists is crucial for the success of a project. Theoretical modeling in physiology usually describes complex systems with many interdependencies. On one hand, these models have to be grounded on experimental data. On the other hand, experimenters must be able to understand the interdependent complexities of the theoretical model in order to interpret the model’s results in the physiological context. We promote interactive, visual simulations as an engaging way to present theoretical models in physiology and to make complex processes tangible. Based on a requirements analysis, we developed a new model for gas exchange in the human alveolus in combination with an interactive simulation software named Alvin. Alvin exceeds the current standard with its spatio-temporal resolution and a combination of visual and quantitative feedback. In Alvin, the course of the simulation can be traced in a three-dimensional rendering of an alveolus and dynamic plots. The user can interact by configuring essential model parameters. Alvin allows to run and compare multiple simulation instances simultaneously. We exemplified the use of Alvin for research by identifying unknown dependencies in published experimental data. Employing a detailed questionnaire, we showed the benefits of Alvin for education. We postulate that interactive, visual simulation of theoretical models, as we have implemented with Alvin on respiratory processes in the alveolus, can be of great help for communication between specialists and thereby advancing research.}, author = {Schmid, Kerstin and Knote, Andreas and Mück, Alexander and Pfeiffer, Keram and von Mammen, Sebastian and Fischer, Sabine C.}, journal = {Frontiers in Bioinformatics}, keywords = {myown}, title = {Interactive, Visual Simulation of a Spatio-Temporal Model of Gas Exchange in the Human Alveolus}, volume = 1, year = 2022 }
Schott, C., Hofmann, S., von Mammen, S.: Parametric Skin Wound Generation for Medical Simulations. 2022 International Conference on Interactive Media, Smart Systems and Emerging Technologies (IMET). S. 1–8 (2022).
- [ Abstract ]
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- [ URL ]
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Medical simulations offer various opportunities to improve treatment training in different areas of medicine. The realism and thus effectiveness of wound care training goes hand in hand with the realism of the wounds themselves. In this paper, we propose a novel approach to (a) procedurally generate convincing-looking wound textures and (b) to dynamically project them onto animated, skinned meshes. Our method allows for creating dermal wounds of different types including abrasions, lacerations and puncture wounds. We analyzed the outcome by recreating visualization instances of these types, demonstrating the applicability of our system.

@inproceedings{9929659, abstract = {Medical simulations offer various opportunities to improve treatment training in different areas of medicine. The realism and thus effectiveness of wound care training goes hand in hand with the realism of the wounds themselves. In this paper, we propose a novel approach to (a) procedurally generate convincing-looking wound textures and (b) to dynamically project them onto animated, skinned meshes. Our method allows for creating dermal wounds of different types including abrasions, lacerations and puncture wounds. We analyzed the outcome by recreating visualization instances of these types, demonstrating the applicability of our system.}, author = {Schott, Christian and Hofmann, Sarah and von Mammen, Sebastian}, booktitle = {2022 International Conference on Interactive Media, Smart Systems and Emerging Technologies (IMET)}, keywords = {via-vr}, month = {oct}, pages = {1-8}, title = {Parametric Skin Wound Generation for Medical Simulations}, year = 2022 }

2021[ to top ]

Steinhaeusser, S.C., Schaper, P., Akuffo, O.B., Friedrich, P., Ön, J., Lugrin, B.: Anthropomorphize me! - Effects of Robot Gender on Listeners’ Perception of the Social Robot NAO in a Storytelling Use Case. In: Bethel, C., Paiva, A., Broadbent, E., Feil-Seifer, D., und Szafir, D. (hrsg.) Companion of the 2021 ACM/IEEE International Conference on Human-Robot Interaction (HRI 2021). ACM (2021).
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@inproceedings{Steinhaeusser_2021, author = {Steinhaeusser, Sophia C. and Schaper, Philipp and Akuffo, Ohenewa Bediako and Friedrich, Paula and Ön, Jülide and Lugrin, Birgit}, booktitle = {Companion of the 2021 ACM/IEEE International Conference on Human-Robot Interaction (HRI 2021)}, editor = {Bethel, Cindy and Paiva, Ana and Broadbent, Elizabeth and Feil-Seifer, David and Szafir, Daniel}, keywords = {storyteller}, publisher = {ACM}, title = {Anthropomorphize me! - Effects of Robot Gender on Listeners' Perception of the Social Robot NAO in a Storytelling Use Case}, year = 2021 }
Geissler, S., Lange, S., Linguaglossa, L., Rossi, D., Zinner, T., Hoßfeld, T.: Discrete-Time Modeling of NFV Accelerators that Exploit Batched Processing. ACM Transactions on Modeling and Performance Evaluation of Computing Systems. 6, 1–27 (2021).
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@article{info3-article-2021-12, author = {Geissler, Stefan and Lange, Stanislav and Linguaglossa, Leonardo and Rossi, Dario and Zinner, Thomas and Hoßfeld, Tobias}, journal = {ACM Transactions on Modeling and Performance Evaluation of Computing Systems}, keywords = {can}, month = 9, number = 3, pages = {1-27}, title = {Discrete-Time Modeling of NFV Accelerators that Exploit Batched Processing}, volume = 6, year = 2021 }
Lugrin, B., Pelachaud, C., Traum, D.: The Handbook on Socially Interactive Agents – 20 Years of Research on Embodied Conversational Agents, Intelligent Virtual Agents, and Social Robotics, Volume 1: Methods, Behavior, Cognition. ACM (2021).
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- [ URL ]
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@book{2021, author = {Lugrin, Birgit and Pelachaud, Catherine and Traum, David}, keywords = {myown}, publisher = {ACM}, title = {The Handbook on Socially Interactive Agents – 20 Years of Research on Embodied Conversational Agents, Intelligent Virtual Agents, and Social Robotics, Volume 1: Methods, Behavior, Cognition}, year = 2021 }
Glémarec, Y., Lugrin, J.-L., Bosser, A.-G., Collins Jackson, A., Buche, C., Latoschik, M.E.: Indifferent or Enthusiastic? Virtual Audiences Animation and Perception in Virtual Reality. Frontiers in Virtual Reality. 2, 72 (2021).
- [ Abstract ]
- [ BibTeX ]
- [ URL ]
- [ DOI ]
In this paper, we present a virtual audience simulation system for Virtual Reality (VR). The system implements an audience perception model controlling the nonverbal behaviors of virtual spectators, such as facial expressions or postures. Groups of virtual spectators are animated by a set of nonverbal behavior rules representing a particular audience attitude (e.g., indifferent or enthusiastic). Each rule specifies a nonverbal behavior category: posture, head movement, facial expression and gaze direction as well as three parameters: type, frequency and proportion. In a first user-study, we asked participants to pretend to be a speaker in VR and then create sets of nonverbal behaviour parameters to simulate different attitudes. Participants manipulated the nonverbal behaviours of single virtual spectator to match a specific levels of engagement and opinion toward them. In a second user-study, we used these parameters to design different types of virtual audiences with our nonverbal behavior rules and evaluated their perceptions. Our results demonstrate our system’s ability to create virtual audiences with three types of different perceived attitudes: indifferent, critical, enthusiastic. The analysis of the results also lead to a set of recommendations and guidelines regarding attitudes and expressions for future design of audiences for VR therapy and training applications.

@article{10.3389/frvir.2021.666232, abstract = {In this paper, we present a virtual audience simulation system for Virtual Reality (VR). The system implements an audience perception model controlling the nonverbal behaviors of virtual spectators, such as facial expressions or postures. Groups of virtual spectators are animated by a set of nonverbal behavior rules representing a particular audience attitude (e.g., indifferent or enthusiastic). Each rule specifies a nonverbal behavior category: posture, head movement, facial expression and gaze direction as well as three parameters: type, frequency and proportion. In a first user-study, we asked participants to pretend to be a speaker in VR and then create sets of nonverbal behaviour parameters to simulate different attitudes. Participants manipulated the nonverbal behaviours of single virtual spectator to match a specific levels of engagement and opinion toward them. In a second user-study, we used these parameters to design different types of virtual audiences with our nonverbal behavior rules and evaluated their perceptions. Our results demonstrate our system’s ability to create virtual audiences with three types of different perceived attitudes: indifferent, critical, enthusiastic. The analysis of the results also lead to a set of recommendations and guidelines regarding attitudes and expressions for future design of audiences for VR therapy and training applications.}, author = {Glémarec, Yann and Lugrin, Jean-Luc and Bosser, Anne-Gwenn and Collins Jackson, Aryana and Buche, Cédric and Latoschik, Marc Erich}, journal = {Frontiers in Virtual Reality}, keywords = {vraudi}, pages = 72, title = {Indifferent or Enthusiastic? Virtual Audiences Animation and Perception in Virtual Reality}, volume = 2, year = 2021 }
Metzger, F., Stulier, N., Borchert, K., Hirth, M.: Relationship Status: It’s Complicated. Using APM as a QoE-qualifying Tempo Metric. Proceedings of the 13th International Conference on Quality of Multimedia Experience (QoMEX 2021) (2021).
- [ BibTeX ]
@inproceedings{info3-inproceedings-2021-13, author = {Metzger, Florian and Stulier, Norman and Borchert, Kathrin and Hirth, Matthias}, booktitle = {Proceedings of the 13th International Conference on Quality of Multimedia Experience (QoMEX 2021)}, keywords = {myown}, month = 6, title = {Relationship Status: It's Complicated. Using APM as a QoE-qualifying Tempo Metric}, year = 2021 }
Kern, F., Kullmann, P., Ganal, E., Korwisi, K., Stingl, R., Niebling, F., Latoschik, M.E.: Off-The-Shelf Stylus: Using XR Devices for Handwriting and Sketching on Physically Aligned Virtual Surfaces. Frontiers in Virtual Reality. 2, 69 (2021).
- [ Abstract ]
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This article introduces the Off-The-Shelf Stylus (OTSS), a framework for 2D interaction (in 3D) as well as for handwriting and sketching with digital pen, ink, and paper on physically aligned virtual surfaces in Virtual, Augmented, and Mixed Reality (VR, AR, MR: XR for short). OTSS supports self-made XR styluses based on consumer-grade six-degrees-of-freedom XR controllers and commercially available styluses. The framework provides separate modules for three basic but vital features: 1) The stylus module provides stylus construction and calibration features. 2) The surface module provides surface calibration and visual feedback features for virtual-physical 2D surface alignment using our so-called 3ViSuAl procedure, and surface interaction features. 3) The evaluation suite provides a comprehensive test bed combining technical measurements for precision, accuracy, and latency with extensive usability evaluations including handwriting and sketching tasks based on established visuomotor, graphomotor, and handwriting research. The framework’s development is accompanied by an extensive open source reference implementation targeting the Unity game engine using an Oculus Rift S headset and Oculus Touch controllers. The development compares three low-cost and low-tech options to equip controllers with a tip and includes a web browser-based surface providing support for interacting, handwriting, and sketching. The evaluation of the reference implementation based on the OTSS framework identified an average stylus precision of 0.98 mm (SD = 0.54 mm) and an average surface accuracy of 0.60 mm (SD = 0.32 mm) in a seated VR environment. The time for displaying the stylus movement as digital ink on the web browser surface in VR was 79.40 ms on average (SD = 23.26 ms), including the physical controller’s motion-to-photon latency visualized by its virtual representation (M = 42.57 ms, SD = 15.70 ms). The usability evaluation (N = 10) revealed a low task load, high usability, and high user experience. Participants successfully reproduced given shapes and created legible handwriting, indicating that the OTSS and it’s reference implementation is ready for everyday use. We provide source code access to our implementation, including stylus and surface calibration and surface interaction features, making it easy to reuse, extend, adapt and/or replicate previous results (https://go.uniwue.de/hci-otss).

@article{kern2021offtheshelf, abstract = {This article introduces the Off-The-Shelf Stylus (OTSS), a framework for 2D interaction (in 3D) as well as for handwriting and sketching with digital pen, ink, and paper on physically aligned virtual surfaces in Virtual, Augmented, and Mixed Reality (VR, AR, MR: XR for short). OTSS supports self-made XR styluses based on consumer-grade six-degrees-of-freedom XR controllers and commercially available styluses. The framework provides separate modules for three basic but vital features: 1) The stylus module provides stylus construction and calibration features. 2) The surface module provides surface calibration and visual feedback features for virtual-physical 2D surface alignment using our so-called 3ViSuAl procedure, and surface interaction features. 3) The evaluation suite provides a comprehensive test bed combining technical measurements for precision, accuracy, and latency with extensive usability evaluations including handwriting and sketching tasks based on established visuomotor, graphomotor, and handwriting research. The framework’s development is accompanied by an extensive open source reference implementation targeting the Unity game engine using an Oculus Rift S headset and Oculus Touch controllers. The development compares three low-cost and low-tech options to equip controllers with a tip and includes a web browser-based surface providing support for interacting, handwriting, and sketching. The evaluation of the reference implementation based on the OTSS framework identified an average stylus precision of 0.98 mm (SD = 0.54 mm) and an average surface accuracy of 0.60 mm (SD = 0.32 mm) in a seated VR environment. The time for displaying the stylus movement as digital ink on the web browser surface in VR was 79.40 ms on average (SD = 23.26 ms), including the physical controller’s motion-to-photon latency visualized by its virtual representation (M = 42.57 ms, SD = 15.70 ms). The usability evaluation (N = 10) revealed a low task load, high usability, and high user experience. Participants successfully reproduced given shapes and created legible handwriting, indicating that the OTSS and it’s reference implementation is ready for everyday use. We provide source code access to our implementation, including stylus and surface calibration and surface interaction features, making it easy to reuse, extend, adapt and/or replicate previous results (https://go.uniwue.de/hci-otss).}, author = {Kern, Florian and Kullmann, Peter and Ganal, Elisabeth and Korwisi, Kristof and Stingl, Rene and Niebling, Florian and Latoschik, Marc Erich}, editor = {Zielasko, Daniel}, journal = {Frontiers in Virtual Reality}, keywords = {vilearn}, pages = 69, title = {Off-The-Shelf Stylus: Using XR Devices for Handwriting and Sketching on Physically Aligned Virtual Surfaces}, volume = 2, year = 2021 }
Gray, N., Dietz, K., Seufert, M., Hoßfeld, T.: High Performance Network Metadata Extraction Using P4 for ML-Based Intrusion Detection Systems. 22nd International Conference on High Performance Switching and Routing (HPSR). , Paris, France (Virtual Conference) (2021).
- [ BibTeX ]
@inproceedings{info3-inproceedings-2021-8, address = {Paris, France (Virtual Conference)}, author = {Gray, Nicholas and Dietz, Katharina and Seufert, Michael and Hoßfeld, Tobias}, booktitle = {22nd International Conference on High Performance Switching and Routing (HPSR)}, keywords = {ucn}, month = 6, title = {High Performance Network Metadata Extraction Using P4 for ML-Based Intrusion Detection Systems}, year = 2021 }
Tran, H.T., Pham Ngoc, N., Hoßfeld, T., Seufert, M., Thang, T.C.: Cumulative Quality Modeling for HTTP Adaptive Streaming. ACM Transactions on Multimedia Computing, Communications, and Applications. 17, 22 (1–24) (2021).
- [ BibTeX ]
@article{info3-article-2021-1, author = {Tran, Huyen TT and Pham Ngoc, Nam and Hoßfeld, Tobias and Seufert, Michael and Thang, Truong Cong}, journal = {ACM Transactions on Multimedia Computing, Communications, and Applications}, keywords = {ucn}, month = 4, number = 1, pages = {22 (1-24)}, title = {Cumulative Quality Modeling for HTTP Adaptive Streaming}, volume = 17, year = 2021 }
Grigorjew, A., Gray, N., Hoßfeld, T.: Dynamic Real-Time Stream Reservation with TAS and Shared Time Windows. 2nd International Workshop on Time-Sensitive and Deterministic Networking (TENSOR) (2021).
- [ Abstract ]
- [ BibTeX ]
Motivated by new use cases such as industrial automation and in-vehicle communication, Time-Sensitive Networking is further improving the layer~2 standards for real-time communication in Ethernet networks. As periodic traffic is a common requirement in such scenarios, the Time Aware Shaper (TAS) is a highly popular mechanism that allows the realization of real-time guarantees in synchronized networks. Most applications in literature suggest to configure the TAS for full stream isolation such that the lowest delays can be achieved. However, this ``zero-queuing'' strategy requires a high amount of computational resources and time, as the configuration of the gate control lists of each port is a complex task, which is not suitable for scenarios with dynamically changing requirements. This paper presents a novel approach with shared time windows. In combination with stream reservation techniques that are commonly applied for asynchronous mechanisms, the network is able to accept new streams during operation without complex reconfiguration, while still benefiting from some degree of isolation compared to conventional asynchronous shapers. The evaluation shows that, given the right circumstances, the number of accepted real-time streams can be improved significantly.

@inproceedings{info3-inproceedings-2021-7, abstract = {Motivated by new use cases such as industrial automation and in-vehicle communication, Time-Sensitive Networking is further improving the layer 2 standards for real-time communication in Ethernet networks. As periodic traffic is a common requirement in such scenarios, the Time Aware Shaper (TAS) is a highly popular mechanism that allows the realization of real-time guarantees in synchronized networks. Most applications in literature suggest to configure the TAS for full stream isolation such that the lowest delays can be achieved. However, this ``zero-queuing'' strategy requires a high amount of computational resources and time, as the configuration of the gate control lists of each port is a complex task, which is not suitable for scenarios with dynamically changing requirements. This paper presents a novel approach with shared time windows. In combination with stream reservation techniques that are commonly applied for asynchronous mechanisms, the network is able to accept new streams during operation without complex reconfiguration, while still benefiting from some degree of isolation compared to conventional asynchronous shapers. The evaluation shows that, given the right circumstances, the number of accepted real-time streams can be improved significantly.}, author = {Grigorjew, Alexej and Gray, Nicholas and Hoßfeld, Tobias}, booktitle = {2nd International Workshop on Time-Sensitive and Deterministic Networking (TENSOR)}, keywords = {ngn}, month = 6, title = {Dynamic Real-Time Stream Reservation with TAS and Shared Time Windows}, year = 2021 }
Korger, A., Baumeister, J.: Rule-based Semantic Relation Extraction in Regulatory Documents. Learning. Knowledge. Data. Analytics. , Munich, Germany (2021).
- [ BibTeX ]
@inproceedings{Korger2021, address = {Munich, Germany}, author = {Korger, Andreas and Baumeister, Joachim}, booktitle = {Learning. Knowledge. Data. Analytics}, keywords = {rokt}, month = {September}, title = {Rule-based Semantic Relation Extraction in Regulatory Documents}, year = 2021 }
Grigorjew, A., Baier, C., Metzger, F., Hoßfeld, T.: Distributed Implementation of Deterministic Networking in Existing Non-TSN Ethernet Switches. Workshop on Time-sensitive and Deterministic Networking (TsDN) (2021).
- [ Abstract ]
- [ BibTeX ]
Deterministic networking is quickly gaining importance, as several domains previously dominated by bus systems are now switching to Ethernet. While standardization efforts, especially from the Time-Sensitive Networking (TSN) group, are ongoing, practical deployments are still far off until configuration guidelines and resource management are able to use these tools to their full potential. As an alternative, this work presents a working implementation of bounded latency with an off-the-shelf non-TSN Ethernet switch. The solution is based on a distributed reservation protocol and admission control. It proves that bounded latency is already possible with simple priority-based transmission, and it provides valuable insights for the development and operation of future real-time networking solutions.

@inproceedings{info3-inproceedings-2021-6, abstract = {Deterministic networking is quickly gaining importance, as several domains previously dominated by bus systems are now switching to Ethernet. While standardization efforts, especially from the Time-Sensitive Networking (TSN) group, are ongoing, practical deployments are still far off until configuration guidelines and resource management are able to use these tools to their full potential. As an alternative, this work presents a working implementation of bounded latency with an off-the-shelf non-TSN Ethernet switch. The solution is based on a distributed reservation protocol and admission control. It proves that bounded latency is already possible with simple priority-based transmission, and it provides valuable insights for the development and operation of future real-time networking solutions.}, author = {Grigorjew, Alexej and Baier, Christian and Metzger, Florian and Hoßfeld, Tobias}, booktitle = {Workshop on Time-sensitive and Deterministic Networking (TsDN)}, keywords = {ngn}, month = 6, title = {Distributed Implementation of Deterministic Networking in Existing Non-TSN Ethernet Switches}, year = 2021 }
Hein, R., Steinbock, J., Eisenmann, M., Latoschik, M.E., Wienrich, C.: Development of the InteractionSuitcase in virtual reality to support inter- and transcultural learning processes in English as Foreign Language education. In: Kienle, A., Harrer, A., Haake, J.M., und Lingnau, A. (hrsg.) DELFI 2021. S. 91–96. Gesellschaft für Informatik e.V., Bonn (2021).
- [ BibTeX ]
@inproceedings{hein2021development, address = {Bonn}, author = {Hein, Rebecca and Steinbock, Jeanine and Eisenmann, Maria and Latoschik, Marc Erich and Wienrich, Carolin}, booktitle = {DELFI 2021}, editor = {Kienle, Andrea and Harrer, Andreas and Haake, Joerg M. and Lingnau, Andreas}, keywords = {rhein}, pages = {91-96}, publisher = {Gesellschaft für Informatik e.V.}, title = {Development of the InteractionSuitcase in virtual reality to support inter- and transcultural learning processes in English as Foreign Language education}, year = 2021 }
Hein, R.M., Wienrich, C., Latoschik, M.E.: A Systematic Review of Foreign Language Learning with Immersive Technologies (2001-2020). AIMS Electronics and Electrical Engineering. 5, 117–145 (2021).
- [ Abstract ]
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This study provides a systematic literature review of research (2001–2020) in the field of teaching and learning a foreign language and intercultural learning using immersive technologies. Based on 2507 sources, 54 articles were selected according to a predefined selection criteria. The review is aimed at providing information about which immersive interventions are being used for foreign language learning and teaching and where potential research gaps exist. The papers were analyzed and coded according to the following categories: (1) investigation form and education level, (2) degree of immersion, and technology used, (3) predictors, and (4) criterions. The review identified key research findings relating the use of immersive technologies for learning and teaching a foreign language and intercultural learning at cognitive, affective, and conative levels. The findings revealed research gaps in the area of teachers as a target group, and virtual reality (VR) as a fully immersive intervention form. Furthermore, the studies reviewed rarely examined behavior, and implicit measurements related to inter- and trans-cultural learning and teaching. Inter- and transcultural learning and teaching especially is an underrepresented investigation subject. Finally, concrete suggestions for future research are given. The systematic review contributes to the challenge of interdisciplinary cooperation between pedagogy, foreign language didactics, and Human-Computer Interaction to achieve innovative teaching-learning formats and a successful digital transformation.

@article{noauthororeditor, abstract = {This study provides a systematic literature review of research (2001–2020) in the field of teaching and learning a foreign language and intercultural learning using immersive technologies. Based on 2507 sources, 54 articles were selected according to a predefined selection criteria. The review is aimed at providing information about which immersive interventions are being used for foreign language learning and teaching and where potential research gaps exist. The papers were analyzed and coded according to the following categories: (1) investigation form and education level, (2) degree of immersion, and technology used, (3) predictors, and (4) criterions. The review identified key research findings relating the use of immersive technologies for learning and teaching a foreign language and intercultural learning at cognitive, affective, and conative levels. The findings revealed research gaps in the area of teachers as a target group, and virtual reality (VR) as a fully immersive intervention form. Furthermore, the studies reviewed rarely examined behavior, and implicit measurements related to inter- and trans-cultural learning and teaching. Inter- and transcultural learning and teaching especially is an underrepresented investigation subject. Finally, concrete suggestions for future research are given. The systematic review contributes to the challenge of interdisciplinary cooperation between pedagogy, foreign language didactics, and Human-Computer Interaction to achieve innovative teaching-learning formats and a successful digital transformation.}, author = {Hein, Rebecca Magdalena and Wienrich, Carolin and Latoschik, Marc Erich}, journal = {AIMS Electronics and Electrical Engineering}, keywords = {rhein}, number = 2, pages = {117-145}, title = {A Systematic Review of Foreign Language Learning with Immersive Technologies (2001-2020)}, volume = 5, year = 2021 }
Tritscher, J., Krause, A., Schl{\"o}r, D., Gwinner, F., von Mammen, S., Hotho, A.: A financial game with opportunities for fraud. IEE COG 2021. 2021, (2021).
- [ Abstract ]
- [ BibTeX ]
- [ URL ]
Even though companies store large amounts of business data in enterprise resource planning (ERP) systems, obtaining data for financial fraud detection is prohibitively difficult due to privacy concerns and companies protecting trade secrets. One possible solution is game-based generation of synthetic ERP data, which poses the challenge of designing an environment that generates realistic ERP data and allows players to commit many different types of fraud. In this work, we design a multiplayer game that allows players to cooperatively run a fictional company, while simultaneously challenging them to maximize their personal gain. We introduce an approach for letting players explore fraud scenarios through emergent gameplay and present a prototype that may be primed with information from real world ERP systems to generate realistic data.

@article{tritscherfinancial, abstract = {Even though companies store large amounts of business data in enterprise resource planning (ERP) systems, obtaining data for financial fraud detection is prohibitively difficult due to privacy concerns and companies protecting trade secrets. One possible solution is game-based generation of synthetic ERP data, which poses the challenge of designing an environment that generates realistic ERP data and allows players to commit many different types of fraud. In this work, we design a multiplayer game that allows players to cooperatively run a fictional company, while simultaneously challenging them to maximize their personal gain. We introduce an approach for letting players explore fraud scenarios through emergent gameplay and present a prototype that may be primed with information from real world ERP systems to generate realistic data.}, author = {Tritscher, Julian and Krause, Anna and Schl{\"o}r, Daniel and Gwinner, Fabian and von Mammen, Sebastian and Hotho, Andreas}, journal = {IEE COG 2021}, keywords = {myown}, title = {A financial game with opportunities for fraud}, volume = 2021, year = 2021 }
Seufert, C., Oberd{\"o}rfer, S., Roth, A., Grafe, S., Lugrin, J.-L., Latoschik, M.E.: Classroom management competency enhancement for student teachers using a fully immersive virtual classroom. Computers & Education. 104410 (2021).
- [ Abstract ]
- [ BibTeX ]
- [ URL ]
- [ DOI ]
The purpose of this study is to examine whether pre-service teachers studying classroom management (CM) in a virtual reality (VR)-supported setting enhance their CM competencies more than students do in a setting using conventional methods. With this aim in mind and to address a lack of available situations of practicing and reflecting CM competencies besides simply gaining theoretical knowledge about CM in education, we integrated a novel fully immersive VR application in selected CM courses. We evaluated the development of self-assessed and instructor-rated CM competencies and the learning quality in the different learning conditions. Additionally, we evaluated the presence, social presence, believability and utility of the VR application and the VR-assisted and video-assisted course. Participants were pre-service teachers (n = 55) of the university of XXX who participated in a quasi-experimental pre-test/post-test intervention. The students were randomly assigned to one of two intervention groups: the test group used ProjectName during the term (n = 39), and the comparison group's learning was video-assisted (n = 16). The instructor rating shows significant differences between the VR group and the video group, the two points of measurement and for the interaction between the condition and time of measurement. It demonstrates a highly significant improvement in CM competencies in the VR setting between the pre-test and post-test (p < 0.001, Cohen's d = 1.06) as compared to the video-based setting. The participants of the VR setting themselves rated their CM competencies in the post-test significantly higher than in the pre-test (p = 0.02, Cohen's d = 0.39). Interestingly, the video group also rated themselves better in the post-test (p = 0.02, Cohen's d = 0.67), which reveals that self-assessment and external assessment show different results. In addition, we observed that even if both groups gained similar theoretical knowledge, the CM competencies developed to a greater degree in the VR-based settings. The participants rated the CM training system a useful tool to evaluate and reflect on individual teacher actions. Its immersion contributes to a high presence and the simulation of realistic scenarios in a CM course. These findings suggest that VR-based settings can lead to a higher benefit in the enhancement of pre-service teachers' CM competencies.

@article{SEUFERT2021104410, abstract = {The purpose of this study is to examine whether pre-service teachers studying classroom management (CM) in a virtual reality (VR)-supported setting enhance their CM competencies more than students do in a setting using conventional methods. With this aim in mind and to address a lack of available situations of practicing and reflecting CM competencies besides simply gaining theoretical knowledge about CM in education, we integrated a novel fully immersive VR application in selected CM courses. We evaluated the development of self-assessed and instructor-rated CM competencies and the learning quality in the different learning conditions. Additionally, we evaluated the presence, social presence, believability and utility of the VR application and the VR-assisted and video-assisted course. Participants were pre-service teachers (n = 55) of the university of XXX who participated in a quasi-experimental pre-test/post-test intervention. The students were randomly assigned to one of two intervention groups: the test group used ProjectName during the term (n = 39), and the comparison group's learning was video-assisted (n = 16). The instructor rating shows significant differences between the VR group and the video group, the two points of measurement and for the interaction between the condition and time of measurement. It demonstrates a highly significant improvement in CM competencies in the VR setting between the pre-test and post-test (p < 0.001, Cohen's d = 1.06) as compared to the video-based setting. The participants of the VR setting themselves rated their CM competencies in the post-test significantly higher than in the pre-test (p = 0.02, Cohen's d = 0.39). Interestingly, the video group also rated themselves better in the post-test (p = 0.02, Cohen's d = 0.67), which reveals that self-assessment and external assessment show different results. In addition, we observed that even if both groups gained similar theoretical knowledge, the CM competencies developed to a greater degree in the VR-based settings. The participants rated the CM training system a useful tool to evaluate and reflect on individual teacher actions. Its immersion contributes to a high presence and the simulation of realistic scenarios in a CM course. These findings suggest that VR-based settings can lead to a higher benefit in the enhancement of pre-service teachers' CM competencies.}, author = {Seufert, Christian and Oberd{\"o}rfer, Sebastian and Roth, Alice and Grafe, Silke and Lugrin, Jean-Luc and Latoschik, Marc Erich}, journal = {Computers & Education}, keywords = {myown}, pages = 104410, title = {Classroom management competency enhancement for student teachers using a fully immersive virtual classroom}, year = 2021 }
Sales, A., Zehe, A., Marinho, L.B., Veloso, A., Hotho, A., Omeliyanenko, J.: Assessing Media Bias in Cross-Linguistic and Cross-National Populations. Proceedings of the International AAAI Conference on Web and Social Media. 15, 561–572 (2021).
- [ BibTeX ]
- [ URL ]
@article{sales2021assessing, author = {Sales, Allan and Zehe, Albin and Marinho, Leandro Balby and Veloso, Adriano and Hotho, Andreas and Omeliyanenko, Janna}, journal = {Proceedings of the International AAAI Conference on Web and Social Media}, keywords = {sentiment}, month = {may}, number = 1, pages = {561-572}, title = {Assessing Media Bias in Cross-Linguistic and Cross-National Populations}, volume = 15, year = 2021 }
Hirth, M., Seufert, M., Lange, S., Meixner, M., Tran-Gia, P.: Performance Evaluation of Hybrid Crowdsensing and Fixed Sensor Systems for Event Detection in Urban Environments. Sensors. 21, 5880 (1–19) (2021).
- [ Abstract ]
- [ BibTeX ]
Crowdsensing offers a cost-effective way to collect large amounts of environmental sensor data. However, the spatial distribution of crowdsensing sensors can hardly be influenced, as the participants carry the sensors, and, additionally, the quality of the crowdsensed data can vary significantly. Hybrid systems that use mobile users in conjunction with fixed sensors might help to overcome these limitations, as such system allow assessing the quality of the submitted crowdsensed data and provide sensor values where no crowdsensing data is available. In this work, we use a simulation study to first analyze a simple crowdsensing system concerning the detection performance of spatial events to highlight the potential and limitations of a pure crowdsourcing system. The results indicate that even if only a small share of inhabitants participates in crowdsensing, events that have locations correlated with the population density can be easily and quickly detected using such a system. On the contrary, events with uniformly randomly distributed locations are much harder to detect using a simple crowdsensing-based approach. A second evaluation shows that hybrid systems improve the detection probability and time. Finally, we illustrate how to compute the minimum number of fixed sensors for given detection time thresholds in our exemplary scenario.

@article{info3-article-2021-4, abstract = {Crowdsensing offers a cost-effective way to collect large amounts of environmental sensor data. However, the spatial distribution of crowdsensing sensors can hardly be influenced, as the participants carry the sensors, and, additionally, the quality of the crowdsensed data can vary significantly. Hybrid systems that use mobile users in conjunction with fixed sensors might help to overcome these limitations, as such system allow assessing the quality of the submitted crowdsensed data and provide sensor values where no crowdsensing data is available. In this work, we use a simulation study to first analyze a simple crowdsensing system concerning the detection performance of spatial events to highlight the potential and limitations of a pure crowdsourcing system. The results indicate that even if only a small share of inhabitants participates in crowdsensing, events that have locations correlated with the population density can be easily and quickly detected using such a system. On the contrary, events with uniformly randomly distributed locations are much harder to detect using a simple crowdsensing-based approach. A second evaluation shows that hybrid systems improve the detection probability and time. Finally, we illustrate how to compute the minimum number of fixed sensors for given detection time thresholds in our exemplary scenario.}, author = {Hirth, Matthias and Seufert, Michael and Lange, Stanislav and Meixner, Markus and Tran-Gia, Phuoc}, journal = {Sensors}, keywords = {ucn}, month = 8, number = 17, pages = {5880 (1-19)}, title = {Performance Evaluation of Hybrid Crowdsensing and Fixed Sensor Systems for Event Detection in Urban Environments}, volume = 21, year = 2021 }
Nguyen Huu, T., TrungKien, N., Van Hoa, N., Thu Huong, T., Wamser, F., Hoßfeld, T.: Energy-Aware Service Function Chain Embedding in Edge-Cloud Environments for IoT Applications. IEEE Internet of Things Journal. (2021).
- [ Abstract ]
- [ BibTeX ]
The implementation of IoT applications faces several challenges in practice, such as compliance with QoS requirements, resource constraints and energy consumption. In this context, the joint paradigm for IoT applications can resolve some of the issues arising in pure cloud computing scenarios, such as those related to latency, energy or privacy. Therefore, an environment could be promising for resource and energy-efficient IoT applications that implement VNF bound together into SFC. However, a resource and energy efficient SFC placement requires smart SFC embedding mechanisms in the environment, as several challenges arise, such as IoT service chain modeling and evaluation, the trade-off between resource allocation, energy efficiency and performance, and the resource dynamics. In this article, we address issues in modeling resource and energy utilization for IoT applications in environments. A smart traffic monitoring IP camera system is deployed as a use case for a realistic modeling of a service chain. The system is implemented in our testbed, which is designed and developed specifically to model and investigate the resource and energy utilization of SFC embedding strategies. A resource and energy-aware SFC strategy in the environment for IoT applications is then proposed. Our algorithm is able to cope with dynamic load and resource situations emerging from dynamic SFC requests. The strategy is evaluated systematically in terms of acceptance ratio of SFC requests, resource efficiency and utilization, power consumption, and VNF migrations depending on the offered system load. Results show that our strategy outperforms some existing approaches in terms of resource and energy efficiency, thus it overcomes the relevant challenges from practice and meets the demands of IoT applications.

@article{info3-article-2021-2, abstract = {The implementation of IoT applications faces several challenges in practice, such as compliance with QoS requirements, resource constraints and energy consumption. In this context, the joint paradigm for IoT applications can resolve some of the issues arising in pure cloud computing scenarios, such as those related to latency, energy or privacy. Therefore, an environment could be promising for resource and energy-efficient IoT applications that implement VNF bound together into SFC. However, a resource and energy efficient SFC placement requires smart SFC embedding mechanisms in the environment, as several challenges arise, such as IoT service chain modeling and evaluation, the trade-off between resource allocation, energy efficiency and performance, and the resource dynamics. In this article, we address issues in modeling resource and energy utilization for IoT applications in environments. A smart traffic monitoring IP camera system is deployed as a use case for a realistic modeling of a service chain. The system is implemented in our testbed, which is designed and developed specifically to model and investigate the resource and energy utilization of SFC embedding strategies. A resource and energy-aware SFC strategy in the environment for IoT applications is then proposed. Our algorithm is able to cope with dynamic load and resource situations emerging from dynamic SFC requests. The strategy is evaluated systematically in terms of acceptance ratio of SFC requests, resource efficiency and utilization, power consumption, and VNF migrations depending on the offered system load. Results show that our strategy outperforms some existing approaches in terms of resource and energy efficiency, thus it overcomes the relevant challenges from practice and meets the demands of IoT applications.}, author = {Nguyen Huu, Thanh and TrungKien, Nguyen and Van Hoa, Ngo and Thu Huong, Truong and Wamser, Florian and Hoßfeld, Tobias}, journal = {IEEE Internet of Things Journal}, keywords = {ecodane}, month = 3, title = {Energy-Aware Service Function Chain Embedding in Edge-Cloud Environments for IoT Applications}, year = 2021 }
Pfister, J., Kobs, K., Hotho, A.: Self-Supervised Multi-Task Pretraining Improves Image Aesthetic Assessment. Proceedings of the IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR) Workshops. S. 816–825 (2021).
- [ BibTeX ]
@inproceedings{Pfister_2021_CVPR, author = {Pfister, Jan and Kobs, Konstantin and Hotho, Andreas}, booktitle = {Proceedings of the IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR) Workshops}, keywords = {myown}, month = {June}, pages = {816-825}, title = {Self-Supervised Multi-Task Pretraining Improves Image Aesthetic Assessment}, year = 2021 }
Unruh, F., Landeck, M., Oberd{\"o}rfer, S., Lugrin, J.-L., Latoschik, M.E.: The Influence of Avatar Embodiment on Time Perception - Towards VR for Time-Based Therapy. Frontiers in Virtual Reality. 2, 71 (2021).
- [ Abstract ]
- [ BibTeX ]
- [ URL ]
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Psycho-pathological conditions, such as depression or schizophrenia, are often accompanied by a distorted perception of time. People suffering from this conditions often report that the passage of time slows down considerably and that they are ``stuck in time.'' Virtual Reality (VR) could potentially help to diagnose and maybe treat such mental conditions. However, the conditions in which a VR simulation could correctly diagnose a time perception deviation are still unknown. In this paper, we present an experiment investigating the difference in time experience with and without a virtual body in VR, also known as avatar. The process of substituting a person's body with a virtual body is called avatar embodiment. Numerous studies demonstrated interesting perceptual, emotional, behavioral, and psychological effects caused by avatar embodiment. However, the relations between time perception and avatar embodiment are still unclear. Whether or not the presence or absence of an avatar is already influencing time perception is still open to question. Therefore, we conducted a between-subjects design with and without avatar embodiment as well as a real condition (avatar vs. no-avatar vs. real). A group of 105 healthy subjects had to wait for seven and a half minutes in a room without any distractors (e.g., no window, magazine, people, decoration) or time indicators (e.g., clocks, sunlight). The virtual environment replicates the real physical environment. Participants were unaware that they will be asked to estimate their waiting time duration as well as describing their experience of the passage of time at a later stage. Our main finding shows that the presence of an avatar is leading to a significantly faster perceived passage of time. It seems to be promising to integrate avatar embodiment in future VR time-based therapy applications as they potentially could modulate a user's perception of the passage of time. We also found no significant difference in time perception between the real and the VR conditions (avatar, no-avatar), but further research is needed to better understand this outcome.

@article{10.3389/frvir.2021.658509, abstract = {Psycho-pathological conditions, such as depression or schizophrenia, are often accompanied by a distorted perception of time. People suffering from this conditions often report that the passage of time slows down considerably and that they are ``stuck in time.'' Virtual Reality (VR) could potentially help to diagnose and maybe treat such mental conditions. However, the conditions in which a VR simulation could correctly diagnose a time perception deviation are still unknown. In this paper, we present an experiment investigating the difference in time experience with and without a virtual body in VR, also known as avatar. The process of substituting a person's body with a virtual body is called avatar embodiment. Numerous studies demonstrated interesting perceptual, emotional, behavioral, and psychological effects caused by avatar embodiment. However, the relations between time perception and avatar embodiment are still unclear. Whether or not the presence or absence of an avatar is already influencing time perception is still open to question. Therefore, we conducted a between-subjects design with and without avatar embodiment as well as a real condition (avatar vs. no-avatar vs. real). A group of 105 healthy subjects had to wait for seven and a half minutes in a room without any distractors (e.g., no window, magazine, people, decoration) or time indicators (e.g., clocks, sunlight). The virtual environment replicates the real physical environment. Participants were unaware that they will be asked to estimate their waiting time duration as well as describing their experience of the passage of time at a later stage. Our main finding shows that the presence of an avatar is leading to a significantly faster perceived passage of time. It seems to be promising to integrate avatar embodiment in future VR time-based therapy applications as they potentially could modulate a user's perception of the passage of time. We also found no significant difference in time perception between the real and the VR conditions (avatar, no-avatar), but further research is needed to better understand this outcome.}, author = {Unruh, Fabian and Landeck, Maximilian and Oberd{\"o}rfer, Sebastian and Lugrin, Jean-Luc and Latoschik, Marc Erich}, journal = {Frontiers in Virtual Reality}, keywords = {vtimes}, pages = 71, title = {The Influence of Avatar Embodiment on Time Perception - Towards VR for Time-Based Therapy}, volume = 2, year = 2021 }
Steininger, M., Kobs, K., Davidson, P., Krause, A., Hotho, A.: Density-based weighting for imbalanced regression. Machine Learning. (2021).
- [ Abstract ]
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- [ URL ]
- [ DOI ]
In many real world settings,imbalanced data impedes model performance of learning algorithms, like neural networks, mostly for rare cases. This is especially problematic for tasks focusing on these rare occurrences. For example, when estimating precipitation, extreme rainfall events are scarce but important considering their potential consequences. While there are numerous well studied solutions for classification settings, most of them cannot be applied to regression easily. Of the few solutions for regression tasks, barely any have explored cost-sensitive learning which is known to have advantages compared to sampling-based methods in classification tasks. In this work, we propose a sample weighting approach for imbalanced regression datasets called DenseWeight and a cost-sensitive learning approach for neural network regression with imbalanced data called DenseLoss based on our weighting scheme. DenseWeight weights data points according to their target value rarities through kernel density estimation (KDE). DenseLoss adjusts each data point’s influence on the loss according to DenseWeight, giving rare data points more influence on modeltraining compared to common data points. We show on multiple differently distributed datasets that DenseLoss significantly improves model performance for rare data points through its density-based weighting scheme. Additionally, we compare DenseLoss to the state-of-the-art method SMOGN, finding that our method mostly yields better performance. Our approach provides more control over model training as it enables us to actively decide on the trade-off between focusing on common or rare cases through a single hyperparameter, allowing the training of better models for rare data points.

@article{steininger2021densitybased, abstract = {In many real world settings,imbalanced data impedes model performance of learning algorithms, like neural networks, mostly for rare cases. This is especially problematic for tasks focusing on these rare occurrences. For example, when estimating precipitation, extreme rainfall events are scarce but important considering their potential consequences. While there are numerous well studied solutions for classification settings, most of them cannot be applied to regression easily. Of the few solutions for regression tasks, barely any have explored cost-sensitive learning which is known to have advantages compared to sampling-based methods in classification tasks. In this work, we propose a sample weighting approach for imbalanced regression datasets called DenseWeight and a cost-sensitive learning approach for neural network regression with imbalanced data called DenseLoss based on our weighting scheme. DenseWeight weights data points according to their target value rarities through kernel density estimation (KDE). DenseLoss adjusts each data point’s influence on the loss according to DenseWeight, giving rare data points more influence on modeltraining compared to common data points. We show on multiple differently distributed datasets that DenseLoss significantly improves model performance for rare data points through its density-based weighting scheme. Additionally, we compare DenseLoss to the state-of-the-art method SMOGN, finding that our method mostly yields better performance. Our approach provides more control over model training as it enables us to actively decide on the trade-off between focusing on common or rare cases through a single hyperparameter, allowing the training of better models for rare data points.}, author = {Steininger, Michael and Kobs, Konstantin and Davidson, Padraig and Krause, Anna and Hotho, Andreas}, editor = {Appice, Annalisa and Escalera, Sergio and Gamez, Jose A. and Trautmann, Heike}, journal = {Machine Learning}, keywords = {regression}, title = {Density-based weighting for imbalanced regression}, year = 2021 }
Oberdörfer, S., Elsässer, A., Grafe, S., Latoschik, M.E.: Grab the Frog: Comparing Intuitive Use and User Experience of a Smartphone-only, AR-only, and Tangible AR Learning Environment. Proceedings of the 23rd International Conference on Mobile Human-Computer Interaction (MobileHCI ’21). (2021).
- [ BibTeX ]
- [ URL ]
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@article{oberdorfer2021comparing, author = {Oberdörfer, Sebastian and Elsässer, Anne and Grafe, Silke and Latoschik, Marc Erich}, journal = {Proceedings of the 23rd International Conference on Mobile Human-Computer Interaction (MobileHCI '21)}, keywords = {oberdoerfer}, month = {September}, title = {Grab the Frog: Comparing Intuitive Use and User Experience of a Smartphone-only, AR-only, and Tangible AR Learning Environment}, year = 2021 }
Loh, F., Poignée, F., Wamser, F., Leidinger, F., Hoßfeld, T.: Uplink vs. Downlink: Machine Learning-Based Quality Prediction for HTTP Adaptive Video Streaming. Sensors. 21, 4172 (2021).
- [ Abstract ]
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Streaming video is responsible for the bulk of Internet traffic these days. For this reason, Internet providers and network operators try to make predictions and assessments about the streaming quality for an end user. Current monitoring solutions are based on a variety of different machine learning approaches. The challenge for providers and operators nowadays is that existing approaches require large amounts of data. In this work, the most relevant quality of experience metrics, i.e., the initial playback delay, the video streaming quality, video quality changes, and video rebuffering events, are examined using a voluminous data set of more than 13,000 YouTube video streaming runs that were collected with the native YouTube mobile app. Three Machine Learning models are developed and compared to estimate playback behavior based on uplink request information. The main focus has been on developing a lightweight approach using as few features and as little data as possible, while maintaining state-of-the-art performance.

@article{info3-article-2021-3, abstract = {Streaming video is responsible for the bulk of Internet traffic these days. For this reason, Internet providers and network operators try to make predictions and assessments about the streaming quality for an end user. Current monitoring solutions are based on a variety of different machine learning approaches. The challenge for providers and operators nowadays is that existing approaches require large amounts of data. In this work, the most relevant quality of experience metrics, i.e., the initial playback delay, the video streaming quality, video quality changes, and video rebuffering events, are examined using a voluminous data set of more than 13,000 YouTube video streaming runs that were collected with the native YouTube mobile app. Three Machine Learning models are developed and compared to estimate playback behavior based on uplink request information. The main focus has been on developing a lightweight approach using as few features and as little data as possible, while maintaining state-of-the-art performance.}, author = {Loh, Frank and Poignée, Fabian and Wamser, Florian and Leidinger, Ferdinand and Hoßfeld, Tobias}, journal = {Sensors}, keywords = {can}, number = 12, pages = 4172, title = {Uplink vs. Downlink: Machine Learning-Based Quality Prediction for HTTP Adaptive Video Streaming}, volume = 21, year = 2021 }
Oberdörfer, S., Birnstiel, S., Latoschik, M.E., Grafe, S.: Mutual Benefits: Interdisciplinary Education of Pre-Service Teachers and HCI Students in VR/AR Learning Environment Design. Frontiers in Education. 6, 233 (2021).
- [ BibTeX ]
- [ URL ]
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@article{oberdorfer2021mutual, author = {Oberdörfer, Sebastian and Birnstiel, Sandra and Latoschik, Marc Erich and Grafe, Silke}, journal = {Frontiers in Education}, keywords = {varyfast}, pages = 233, title = {Mutual Benefits: Interdisciplinary Education of Pre-Service Teachers and HCI Students in VR/AR Learning Environment Design}, volume = 6, year = 2021 }
G{\"u}der, G., Wilkesmann, J., Scholz, N., Leppich, R., D{\"u}king, P., Sperlich, B., Rost, C., Frantz, S., Morbach, C., Sahiti, F., others: Establishing a cardiac training group for patients with heart failure: the “HIP-in-W{\"u}rzburg” study. Clinical Research in Cardiology. 1–10 (2021).
- [ BibTeX ]
@article{guder2021establishing, author = {G{\"u}der, G{\"u}lmisal and Wilkesmann, Joana and Scholz, Nina and Leppich, Robert and D{\"u}king, Peter and Sperlich, Billy and Rost, Christian and Frantz, Stefan and Morbach, Caroline and Sahiti, Floran and others}, journal = {Clinical Research in Cardiology}, keywords = {myown}, pages = {1–10}, publisher = {Springer}, title = {Establishing a cardiac training group for patients with heart failure: the “HIP-in-W{\"u}rzburg” study}, year = 2021 }
Halbig, A., Latoschik, M.E.: A Systematic Review of Physiological Measurements, Factors, Methods, and Applications in Virtual Reality. Frontiers in Virtual Reality. 2, 89 (2021).
- [ Abstract ]
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- [ URL ]
- [ DOI ]
Measurements of physiological parameters provide an objective, often non-intrusive, and (at least semi-)automatic evaluation and utilization of user behavior. In addition, specific hardware devices of Virtual Reality (VR) often ship with built-in sensors, i.e. eye-tracking and movements sensors. Hence, the combination of physiological measurements and VR applications seems promising. Several approaches have investigated the applicability and benefits of this combination for various fields of applications. However, the range of possible application fields, coupled with potentially useful and beneficial physiological parameters, types of sensor, target variables and factors, and analysis approaches and techniques is manifold. This article provides a systematic overview and an extensive state-of-the-art review of the usage of physiological measurements in VR. We identified 1,119 works that make use of physiological measurements in VR. Within these, we identified 32 approaches that focus on the classification of characteristics of experience, common in VR applications. The first part of this review categorizes the 1,119 works by field of application, i.e. therapy, training, entertainment, and communication and interaction, as well as by the specific target factors and variables measured by the physiological parameters. An additional category summarizes general VR approaches applicable to all specific fields of application since they target typical VR qualities. In the second part of this review, we analyze the target factors and variables regarding the respective methods used for an automatic analysis and, potentially, classification. For example, we highlight which measurement setups have been proven to be sensitive enough to distinguish different levels of arousal, valence, anxiety, stress, or cognitive workload in the virtual realm. This work may prove useful for all researchers wanting to use physiological data in VR and who want to have a good overview of prior approaches taken, their benefits and potential drawbacks.

@article{10.3389/frvir.2021.694567, abstract = {Measurements of physiological parameters provide an objective, often non-intrusive, and (at least semi-)automatic evaluation and utilization of user behavior. In addition, specific hardware devices of Virtual Reality (VR) often ship with built-in sensors, i.e. eye-tracking and movements sensors. Hence, the combination of physiological measurements and VR applications seems promising. Several approaches have investigated the applicability and benefits of this combination for various fields of applications. However, the range of possible application fields, coupled with potentially useful and beneficial physiological parameters, types of sensor, target variables and factors, and analysis approaches and techniques is manifold. This article provides a systematic overview and an extensive state-of-the-art review of the usage of physiological measurements in VR. We identified 1,119 works that make use of physiological measurements in VR. Within these, we identified 32 approaches that focus on the classification of characteristics of experience, common in VR applications. The first part of this review categorizes the 1,119 works by field of application, i.e. therapy, training, entertainment, and communication and interaction, as well as by the specific target factors and variables measured by the physiological parameters. An additional category summarizes general VR approaches applicable to all specific fields of application since they target typical VR qualities. In the second part of this review, we analyze the target factors and variables regarding the respective methods used for an automatic analysis and, potentially, classification. For example, we highlight which measurement setups have been proven to be sensitive enough to distinguish different levels of arousal, valence, anxiety, stress, or cognitive workload in the virtual realm. This work may prove useful for all researchers wanting to use physiological data in VR and who want to have a good overview of prior approaches taken, their benefits and potential drawbacks.}, author = {Halbig, Andreas and Latoschik, Marc Erich}, journal = {Frontiers in Virtual Reality}, keywords = {via-vr}, pages = 89, title = {A Systematic Review of Physiological Measurements, Factors, Methods, and Applications in Virtual Reality}, volume = 2, year = 2021 }
Dallmann, A., Zoller, D., Hotho, A.: A Case Study on Sampling Strategies for Evaluating Neural Sequential Item Recommendation Models. Fifteenth {ACM} Conference on Recommender Systems. {ACM} (2021).
- [ BibTeX ]
- [ DOI ]
@inproceedings{dallmann2021study, author = {Dallmann, Alexander and Zoller, Daniel and Hotho, Andreas}, booktitle = {Fifteenth {ACM} Conference on Recommender Systems}, keywords = {systems}, month = {sep}, publisher = {{ACM}}, title = {A Case Study on Sampling Strategies for Evaluating Neural Sequential Item Recommendation Models}, year = 2021 }
Ripka, G., Grafe, S., Latoschik, M.E.: Peer group supervision in Zoom and social VR-Preparing preservice teachers for planning and designing digital media integrated classes. EdMedia+ Innovate Learning. S. 602–616. Association for the Advancement of Computing in Education (AACE) (2021).
- [ Abstract ]
- [ BibTeX ]
21-century challenges demand a change towards collaborative and constructive seminar designs in initial teacher education regarding preservice teachers acquiring meta-conceptual awareness (TPACK) about how to implement emerging technologies in their future profession. Against this background the paper addresses the following research questions: 1) How should a pedagogical concept for remote initial teacher education be designed to promote metacognitive learning processes of preservice teachers? 2) How do preservice teachers perceive these learning processes in video-based communication and social VR? Regarding the pedagogical concept, peer group supervision and an action-and development-oriented approach using Zoom and social VR were identified as relevant for an instructional design that provides collaborative and constructive learning processes for students. In this exploratory study, 17 students participated in two iterative cycles of peer group supervision performing design tasks in groups. A content analysis of reflective video statements and qualitative group interviews was carried out using a qualitative research design. Results indicate the successful implementation of peer group supervision. Regarding media's implementation, Zoom's screen-sharing option and breakout session benefitted the consultation process as well as social VR's "realistic" experience of creating a "sense of community".

@inproceedings{ripka2021peer, abstract = {21-century challenges demand a change towards collaborative and constructive seminar designs in initial teacher education regarding preservice teachers acquiring meta-conceptual awareness (TPACK) about how to implement emerging technologies in their future profession. Against this background the paper addresses the following research questions: 1) How should a pedagogical concept for remote initial teacher education be designed to promote metacognitive learning processes of preservice teachers? 2) How do preservice teachers perceive these learning processes in video-based communication and social VR? Regarding the pedagogical concept, peer group supervision and an action-and development-oriented approach using Zoom and social VR were identified as relevant for an instructional design that provides collaborative and constructive learning processes for students. In this exploratory study, 17 students participated in two iterative cycles of peer group supervision performing design tasks in groups. A content analysis of reflective video statements and qualitative group interviews was carried out using a qualitative research design. Results indicate the successful implementation of peer group supervision. Regarding media's implementation, Zoom's screen-sharing option and breakout session benefitted the consultation process as well as social VR's "realistic" experience of creating a "sense of community".}, author = {Ripka, Gabriela and Grafe, Silke and Latoschik, Marc Erich}, booktitle = {EdMedia+ Innovate Learning}, keywords = {myown}, organization = {Association for the Advancement of Computing in Education (AACE)}, pages = {602-616}, title = {Peer group supervision in Zoom and social VR-Preparing preservice teachers for planning and designing digital media integrated classes}, year = 2021 }
Fischer, E., Zoller, D., Hotho, A.: Comparison of Transformer-Based Sequential Product Recommendation Models for the Coveo Data Challenge. SIGIR Workshop On eCommerce. (2021).
- [ BibTeX ]
@article{fischer2021comparison, author = {Fischer, Elisabeth and Zoller, Daniel and Hotho, Andreas}, journal = {SIGIR Workshop On eCommerce}, keywords = {transformer}, month = {July}, title = {Comparison of Transformer-Based Sequential Product Recommendation Models for the Coveo Data Challenge}, year = 2021 }
Wehner, N., Seufert, M., Schüler, J., Casas, P., Hoßfeld, T.: How are your Apps Doing? QoE Inference and Analysis in Mobile Devices. 17th International Conference on Network and Service Management (CNSM). , Izmir, Turkey (Virtual Conference) (2021).
- [ Abstract ]
- [ BibTeX ]
Web browsing has become the most important application of the Internet for the end user. When it comes to mobile devices, web services are mainly accessed through apps. This paper tackles the problem of Web Quality of Experience (QoE) in mobile devices, with a specific focus on apps QoE monitoring and analysis, using in-network (encrypted) traffic measurements. Measuring apps QoE is complex, not only from an instrumentation point of view, but also from the heterogeneity of user interactions which might realize substantially different user experience. To this end, we conduct a feasibility study on four specific and popular Android apps and their corresponding web services. Our test automation framework emulates and measures different user interactions commonly executed during an app session, including the app startup, clicking, scrolling, and searching. The resulting traffic is characterized on different dimensions, and machine learning models are trained to identify web services, apps, and user interactions, and to infer their QoE. The proposed models can correctly identify the specific web service and app in 86% of the cases and accurately estimate the associated QoE with small errors. Our preliminary study represents a first step towards an in-network, web QoE monitoring solution for mobile-device apps.

@inproceedings{info3-inproceedings-2021-15, abstract = {Web browsing has become the most important application of the Internet for the end user. When it comes to mobile devices, web services are mainly accessed through apps. This paper tackles the problem of Web Quality of Experience (QoE) in mobile devices, with a specific focus on apps QoE monitoring and analysis, using in-network (encrypted) traffic measurements. Measuring apps QoE is complex, not only from an instrumentation point of view, but also from the heterogeneity of user interactions which might realize substantially different user experience. To this end, we conduct a feasibility study on four specific and popular Android apps and their corresponding web services. Our test automation framework emulates and measures different user interactions commonly executed during an app session, including the app startup, clicking, scrolling, and searching. The resulting traffic is characterized on different dimensions, and machine learning models are trained to identify web services, apps, and user interactions, and to infer their QoE. The proposed models can correctly identify the specific web service and app in 86% of the cases and accurately estimate the associated QoE with small errors. Our preliminary study represents a first step towards an in-network, web QoE monitoring solution for mobile-device apps.}, address = {Izmir, Turkey (Virtual Conference)}, author = {Wehner, Nikolas and Seufert, Michael and Schüler, Joshua and Casas, Pedro and Hoßfeld, Tobias}, booktitle = {17th International Conference on Network and Service Management (CNSM)}, keywords = {ucn}, month = 10, title = {How are your Apps Doing? QoE Inference and Analysis in Mobile Devices}, year = 2021 }
Seufert, A., Wamser, F., Yarish, D., Macdonald, H., Hoßfeld, T.: QoE Models in the Wild: Comparing Video QoE Models Using a Crowdsourced Data Set. 2021 13th International Conference on Quality of Multimedia Experience (QoMEX). , Montreal, Canada (virtual conference) (2021).
- [ Abstract ]
- [ BibTeX ]
Crowdsourced measurements solve the problem of being able to assess the performance of a communication network from an end-user perspective, but the new characteristics of the data pose new challenges for QoE modeling. In contrast to existing laboratory or network measurements, this type of measurement at the end-user device primarily involves taking a large number of short sample measurements, which, however, are rich in measured parameters, including many user-, application-, and device-related parameters. To test the applicability and to facilitate the integration of such data, we applied four QoE models from the literature to 290k worldwide video streaming measurements from a commercial data set from August to October 2020. In this work, we will therefore first describe the crowdsourcing video streaming data set to provide insights into the properties of video streaming KPIs in the real-world. Second, we run four popular QoE models using this data set, compare the resulting QoE scores, and derive the impact of individual KPIs for each model. We show that the models assess the QoE at least differently, but sometimes with contradicting statements. Reading this paper, it becomes evident that more work and subjective studies, based on real-world data like the one we have shown, are needed to extend the current QoE models.

@inproceedings{info3-inproceedings-2021-12, abstract = {Crowdsourced measurements solve the problem of being able to assess the performance of a communication network from an end-user perspective, but the new characteristics of the data pose new challenges for QoE modeling. In contrast to existing laboratory or network measurements, this type of measurement at the end-user device primarily involves taking a large number of short sample measurements, which, however, are rich in measured parameters, including many user-, application-, and device-related parameters. To test the applicability and to facilitate the integration of such data, we applied four QoE models from the literature to 290k worldwide video streaming measurements from a commercial data set from August to October 2020. In this work, we will therefore first describe the crowdsourcing video streaming data set to provide insights into the properties of video streaming KPIs in the real-world. Second, we run four popular QoE models using this data set, compare the resulting QoE scores, and derive the impact of individual KPIs for each model. We show that the models assess the QoE at least differently, but sometimes with contradicting statements. Reading this paper, it becomes evident that more work and subjective studies, based on real-world data like the one we have shown, are needed to extend the current QoE models.}, address = {Montreal, Canada (virtual conference)}, author = {Seufert, Anika and Wamser, Florian and Yarish, David and Macdonald, Hunter and Hoßfeld, Tobias}, booktitle = {2021 13th International Conference on Quality of Multimedia Experience (QoMEX)}, keywords = {can}, month = 6, title = {QoE Models in the Wild: Comparing Video QoE Models Using a Crowdsourced Data Set}, year = 2021 }
Metzger, F., Schröder, S., Ratetseder, A.: Subjective And Objective Assessment Of Video Game Context Factors, (2021).
- [ BibTeX ]
@misc{info3-misc-2021-1, author = {Metzger, Florian and Schröder, Svenja and Ratetseder, Albert}, howpublished = {https://nbn-resolving.org/urn:nbn:de:bvb:20-opus-242471}, keywords = {myown}, month = 8, title = {Subjective And Objective Assessment Of Video Game Context Factors}, year = 2021 }
Metzger, F., Rafetseder, A., Schröder, S., Zwickl, P.: The Prospects of Cloud Gaming: Do the Benefits Outweigh the Costs?, (2021).
- [ BibTeX ]
@misc{info3-misc-2021-2, author = {Metzger, Florian and Rafetseder, Albert and Schröder, Svenja and Zwickl, Patrick}, howpublished = {https://nbn-resolving.org/urn:nbn:de:bvb:20-opus-242452}, keywords = {myown}, month = 8, title = {The Prospects of Cloud Gaming: Do the Benefits Outweigh the Costs?}, year = 2021 }
Oberdörfer, S., Heidrich, D., Birnstiel, S., Latoschik, M.E.: Enchanted by Your Surrounding? Measuring the Effects of Immersion and Design of Virtual Environments on Decision-Making. Frontiers in Virtual Reality. 2, 101 (2021).
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- [ URL ]
- [ DOI ]
@article{oberdorfer2021enchanted, author = {Oberdörfer, Sebastian and Heidrich, David and Birnstiel, Sandra and Latoschik, Marc Erich}, journal = {Frontiers in Virtual Reality}, keywords = {oberdoerfer}, pages = 101, title = {Enchanted by Your Surrounding? Measuring the Effects of Immersion and Design of Virtual Environments on Decision-Making}, volume = 2, year = 2021 }
Gall, D., Roth, D., Stauffert, J.-P., Zarges, J., Latoschik, M.E.: Virtual Body Ownership Intensifies Emotional Responses to Virtual Stimuli. Frontiers in Psychology - Cognitive Science. 12, 3833 (2021).
- [ Abstract ]
- [ BibTeX ]
- [ URL ]
- [ DOI ]
Modulating emotional responses to virtual stimuli is a fundamental goal of many immersive interactive applications. In this study, we leverage the illusion of illusory embodiment and show that owning a virtual body provides means to modulate emotional responses. In a single-factor repeated-measures experiment, we manipulated the degree of illusory embodiment and assessed the emotional responses to virtual stimuli. We presented emotional stimuli in the same environment as the virtual body. Participants experienced higher arousal, dominance, and more intense valence in the high embodiment condition compared to the low embodiment condition. The illusion of embodiment thus intensifies the emotional processing of the virtual environment. This result suggests that artificial bodies can increase the effectiveness of immersive applications psychotherapy, entertainment, computer-mediated social interactions, or health applications.

@article{gall2021virtual, abstract = {Modulating emotional responses to virtual stimuli is a fundamental goal of many immersive interactive applications. In this study, we leverage the illusion of illusory embodiment and show that owning a virtual body provides means to modulate emotional responses. In a single-factor repeated-measures experiment, we manipulated the degree of illusory embodiment and assessed the emotional responses to virtual stimuli. We presented emotional stimuli in the same environment as the virtual body. Participants experienced higher arousal, dominance, and more intense valence in the high embodiment condition compared to the low embodiment condition. The illusion of embodiment thus intensifies the emotional processing of the virtual environment. This result suggests that artificial bodies can increase the effectiveness of immersive applications psychotherapy, entertainment, computer-mediated social interactions, or health applications.}, author = {Gall, Dominik and Roth, Daniel and Stauffert, Jan-Philipp and Zarges, Julian and Latoschik, Marc Erich}, editor = {DiPaola, Steve Richard and Bernardet, Ulysses and Gratch, Jonathan}, journal = {Frontiers in Psychology - Cognitive Science}, keywords = {myown}, pages = 3833, title = {Virtual Body Ownership Intensifies Emotional Responses to Virtual Stimuli}, volume = 12, year = 2021 }
Kobs, K., Schäfer, C., Steininger, M., Krause, A., Baumhauer, R., Paeth, H., Hotho, A.: Semi-Supervised Learning for Grain Size Distribution Interpolation. Pattern Recognition. ICPR International Workshops and Challenges: Virtual Event, January 10--15, 2021, Proceedings, Part VI. S. 34–44. Springer International Publishing (2021).
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@inproceedings{kobs2021semi, author = {Kobs, Konstantin and Schäfer, Christian and Steininger, Michael and Krause, Anna and Baumhauer, Roland and Paeth, Heiko and Hotho, Andreas}, booktitle = {Pattern Recognition. ICPR International Workshops and Challenges: Virtual Event, January 10–15, 2021, Proceedings, Part VI}, keywords = {myown}, organization = {Springer International Publishing}, pages = {34–44}, title = {Semi-Supervised Learning for Grain Size Distribution Interpolation}, year = 2021 }
Kobs, K., Steininger, M., Dulny, A., Hotho, A.: Do Different Deep Metric Learning Losses Lead to Similar Learned Features?. Proceedings of the IEEE/CVF International Conference on Computer Vision (ICCV). 10644–10654 (2021).
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@article{noauthororeditor, author = {Kobs, Konstantin and Steininger, Michael and Dulny, Andrzej and Hotho, Andreas}, journal = {Proceedings of the IEEE/CVF International Conference on Computer Vision (ICCV)}, keywords = {myown}, month = {October}, pages = {10644-10654}, title = {Do Different Deep Metric Learning Losses Lead to Similar Learned Features?}, year = 2021 }
Krop, P., Straka, S., Ullrich, M., Ertl, M., Latoschik, M.E.: IT-Supported request management for clinical radiology: Analyzing the Radiological Order Workflow through Contextual Interviews. Mensch und Computer 2021 (MuC ’21), September 5-8, 2021, Ingolstadt, Germany. S. 1–7. Association for Computing Machinery, New York, NY, USA (2021).
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Requests for radiological examinations in large medical facilities are a distributed and complex process with potential health-related risks for patients. A user-centered qualitative analysis with contextual interviews uncovered nine core problems, which hinder work efficiency and patient care: (1) Difficulties to access patient data & requests, (2) the large number of phone calls, (3) restricted & abused access rights, (4) request status difficult to track, (5) paper notes used for patient data, (6) lack of assistance for data entry, (7) frustration through documentation, (8) IT-systems not self-explanatory, and (9) conflict between physicians and radiologists.Contextual interviews were found to be a well fitting method to analyze and understand this complex process with multiple user roles. This analysis showed that there is room for improvement in the underlying IT systems, workflows and infrastructure. Our data gave useful insight into solutions to these problems and how we can use technology to improve all aspects of the request management. We are currently addressing those issues with a user-centered design process to design and implement a mobile application, which we will present in future work.

@inproceedings{kropstraka21, abstract = {Requests for radiological examinations in large medical facilities are a distributed and complex process with potential health-related risks for patients. A user-centered qualitative analysis with contextual interviews uncovered nine core problems, which hinder work efficiency and patient care: (1) Difficulties to access patient data & requests, (2) the large number of phone calls, (3) restricted & abused access rights, (4) request status difficult to track, (5) paper notes used for patient data, (6) lack of assistance for data entry, (7) frustration through documentation, (8) IT-systems not self-explanatory, and (9) conflict between physicians and radiologists.Contextual interviews were found to be a well fitting method to analyze and understand this complex process with multiple user roles. This analysis showed that there is room for improvement in the underlying IT systems, workflows and infrastructure. Our data gave useful insight into solutions to these problems and how we can use technology to improve all aspects of the request management. We are currently addressing those issues with a user-centered design process to design and implement a mobile application, which we will present in future work.}, address = {New York, NY, USA}, author = {Krop, Philipp and Straka, Samantha and Ullrich, Melanie and Ertl, Maximilian and Latoschik, Marc Erich}, booktitle = {Mensch und Computer 2021 (MuC '21), September 5-8, 2021, Ingolstadt, Germany}, keywords = {straka}, pages = {1-7}, publisher = {Association for Computing Machinery}, title = {IT-Supported request management for clinical radiology: Analyzing the Radiological Order Workflow through Contextual Interviews}, year = 2021 }
Lugrin, B.: Introduction to Socially Interactive Agents. In: Lugrin, B., Pelachaud, C., und Traum, D. (hrsg.) The Handbook on Socially Interactive Agents – 20 Years of Research on Embodied Conversational Agents, Intelligent Virtual Agents, and Social Robotics, Volume 1: Methods, Behavior, Cognition. S. 1–20. ACM (2021).
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@incollection{Lugrin_2021, author = {Lugrin, Birgit}, booktitle = {The Handbook on Socially Interactive Agents – 20 Years of Research on Embodied Conversational Agents, Intelligent Virtual Agents, and Social Robotics, Volume 1: Methods, Behavior, Cognition}, editor = {Lugrin, Birgit and Pelachaud, Catherine and Traum, David}, keywords = {myown}, pages = {1-20}, publisher = {ACM}, title = {Introduction to Socially Interactive Agents}, year = 2021 }
von Mammen, S.: Motivating Interactive Self-Organisation. Lifelike Computing Systems Workshop 2020 and 2021. (2021).
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@article{von2021motivating, author = {von Mammen, Sebastian}, journal = {Lifelike Computing Systems Workshop 2020 and 2021}, keywords = {myown}, title = {Motivating Interactive Self-Organisation}, year = 2021 }
Lesch, V., Hadry, M., Kounev, S., Krupitzer, C.: A Case Study on Optimization of Platooning Coordination. Universit{ä}t W{ü}rzburg and Universit{ä}t Hohenheim (2021).
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@techreport{lesch2021studyplatooning, author = {Lesch, Veronika and Hadry, Marius and Kounev, Samuel and Krupitzer, Christian}, institution = {Universit{ä}t W{ü}rzburg and Universit{ä}t Hohenheim}, keywords = {myown}, title = {A Case Study on Optimization of Platooning Coordination}, year = 2021 }
Schröter, T., Tiede, J., Latoschik, M.E.: Fostering Teacher Educator Technology Competencies (TETCs) in and with Virtual Reality. A Case Study. In: Bastiaens, T. (hrsg.) Proceedings of EdMedia + Innovate Learning. S. 617–629. Association for the Advancement of Computing in Education (AACE) (2021).
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@conference{schroter2021fostering, author = {Schröter, Thomas and Tiede, Jennifer and Latoschik, Marc Erich}, booktitle = {Proceedings of EdMedia + Innovate Learning}, editor = {Bastiaens, T.}, keywords = {myown}, organization = {Association for the Advancement of Computing in Education (AACE)}, pages = {617-629}, publisher = {Association for the Advancement of Computing in Education (AACE)}, title = {Fostering Teacher Educator Technology Competencies (TETCs) in and with Virtual Reality. A Case Study}, year = 2021 }
Schröter, T., Tiede, J., Grafe, S., Latoschik, M.E.: Fostering Teacher Educator Technology Competencies (TETCs) in and with Virtual Reality. Results from an Exploratory Study. In: Bastiaens, T. (hrsg.) Proceedings of Innovate Learning Summit 2021. S. 160–170. Association for the Advancement of Computing in Education (AACE), Online, United States (2021).
- [ Abstract ]
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This exploratory study presents the findings and implications of a three-hour further development workshop implemented with a convenience sample of six teacher educators from a German university. The workshop aimed at fostering the Teacher Educator Technology Competencies (TETCs)—with a special focus on virtual reality (VR)—while reverting to the didactic principle of action orientation. To test whether this didactic principle is suitable for fostering the media pedagogical competencies of the target group in and with VR and to identify further design principles, a mixed-methods approach was utilized. The data collection consisted of focus group interviews, which were analyzed via qualitative content analysis, and Teacher Educator Technology Surveys (TETS). The analysis revealed that action orientation is a valuable addition to established didactical models in higher education (HE). Also...

@inproceedings{SchrTiedGraf2021yx, abstract = {This exploratory study presents the findings and implications of a three-hour further development workshop implemented with a convenience sample of six teacher educators from a German university. The workshop aimed at fostering the Teacher Educator Technology Competencies (TETCs)—with a special focus on virtual reality (VR)—while reverting to the didactic principle of action orientation. To test whether this didactic principle is suitable for fostering the media pedagogical competencies of the target group in and with VR and to identify further design principles, a mixed-methods approach was utilized. The data collection consisted of focus group interviews, which were analyzed via qualitative content analysis, and Teacher Educator Technology Surveys (TETS). The analysis revealed that action orientation is a valuable addition to established didactical models in higher education (HE). Also...}, address = {Online, United States}, author = {Schröter, Thomas and Tiede, Jennifer and Grafe, Silke and Latoschik, Marc Erich}, booktitle = {Proceedings of Innovate Learning Summit 2021}, editor = {Bastiaens, Theo}, keywords = {myown}, month = {November}, pages = {160–170}, publisher = {Association for the Advancement of Computing in Education (AACE)}, title = {Fostering Teacher Educator Technology Competencies (TETCs) in and with Virtual Reality. Results from an Exploratory Study.}, year = 2021 }
Weber, D., Hertweck, S., Alwanni, H., Fiederer, L.D.J., Wang, X., Unruh, F., Fischbach, M., Latoschik, M.E., Ball, T.: A Structured Approach to Test the Signal Quality of Electroencephalography Measurements During Use of Head-Mounted Displays for Virtual Reality Applications. Frontiers in Neuroscience. 15, 1527 (2021).
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Joint applications of virtual reality (VR) systems and electroencephalography (EEG) offer numerous new possibilities ranging from behavioral science to therapy. VR systems allow for highly controlled experimental environments, while EEG offers a non-invasive window to brain activity with a millisecond-ranged temporal resolution. However, EEG measurements are highly susceptible to electromagnetic (EM) noise and the influence of EM noise of head-mounted-displays (HMDs) on EEG signal quality has not been conclusively investigated. In this paper, we propose a structured approach to test HMDs for EM noise potentially harmful to EEG measures. The approach verifies the impact of HMDs on the frequency- and time-domain of the EEG signal recorded in healthy subjects. The verification task includes a comparison of conditions with and without an HMD during (i) an eyes-open vs. eyes-closed task, and (ii) with respect to the sensory- evoked brain activity. The approach is developed and tested to derive potential effects of two commercial HMDs, the Oculus Rift and the HTC Vive Pro, on the quality of 64-channel EEG measurements. The results show that the HMDs consistently introduce artifacts, especially at the line hum of 50 Hz and the HMD refresh rate of 90 Hz, respectively, and their harmonics. The frequency range that is typically most important in non-invasive EEG research and applications (<50 Hz) however, remained largely unaffected. Hence, our findings demonstrate that high-quality EEG recordings, at least in the frequency range up to 50 Hz, can be obtained with the two tested HMDs. However, the number of commercially available HMDs is constantly rising. We strongly suggest to thoroughly test such devices upfront since each HMD will most likely have its own EM footprint and this article provides a structured approach to implement such tests with arbitrary devices.

@article{weber2021structured, abstract = {Joint applications of virtual reality (VR) systems and electroencephalography (EEG) offer numerous new possibilities ranging from behavioral science to therapy. VR systems allow for highly controlled experimental environments, while EEG offers a non-invasive window to brain activity with a millisecond-ranged temporal resolution. However, EEG measurements are highly susceptible to electromagnetic (EM) noise and the influence of EM noise of head-mounted-displays (HMDs) on EEG signal quality has not been conclusively investigated. In this paper, we propose a structured approach to test HMDs for EM noise potentially harmful to EEG measures. The approach verifies the impact of HMDs on the frequency- and time-domain of the EEG signal recorded in healthy subjects. The verification task includes a comparison of conditions with and without an HMD during (i) an eyes-open vs. eyes-closed task, and (ii) with respect to the sensory- evoked brain activity. The approach is developed and tested to derive potential effects of two commercial HMDs, the Oculus Rift and the HTC Vive Pro, on the quality of 64-channel EEG measurements. The results show that the HMDs consistently introduce artifacts, especially at the line hum of 50 Hz and the HMD refresh rate of 90 Hz, respectively, and their harmonics. The frequency range that is typically most important in non-invasive EEG research and applications (<50 Hz) however, remained largely unaffected. Hence, our findings demonstrate that high-quality EEG recordings, at least in the frequency range up to 50 Hz, can be obtained with the two tested HMDs. However, the number of commercially available HMDs is constantly rising. We strongly suggest to thoroughly test such devices upfront since each HMD will most likely have its own EM footprint and this article provides a structured approach to implement such tests with arbitrary devices.}, author = {Weber, Desirée and Hertweck, Stephan and Alwanni, Hisham and Fiederer, Lukas D. J. and Wang, Xi and Unruh, Fabian and Fischbach, Martin and Latoschik, Marc Erich and Ball, Tonio}, journal = {Frontiers in Neuroscience}, keywords = {myown}, pages = 1527, title = {A Structured Approach to Test the Signal Quality of Electroencephalography Measurements During Use of Head-Mounted Displays for Virtual Reality Applications}, volume = 15, year = 2021 }
Herrnleben, S., Leidinger, M., Lesch, V., Prantl, T., Grohmann, J., Krupitzer, C., Kounev, S.: ComBench: A Benchmarking Framework for Publish/Subscribe Communication Protocols Under Network Limitations. In: Zhao, Q. und Xia, L. (hrsg.) Performance Evaluation Methodologies and Tools. S. 72–92. Springer International Publishing, Cham (2021).
- [ Abstract ]
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Efficient and dependable communication is a highly relevant aspect for Internet of Things (IoT) systems in which tiny sensors, actuators, wearables, or other smart devices exchange messages. Various publish/subscribe protocols address the challenges of communication in IoT systems. The selection process of a suitable protocol should consider the communication behavior of the application, the protocol's performance, the resource requirements on the end device, and the network connection quality, as IoT environments often rely on wireless networks. Benchmarking is a common approach to evaluate and compare systems, considering the performance and aspects like dependability or security. In this paper, we present our IoT communication benchmarking framework ComBench for publish/subscribe protocols focusing on constrained networks with varying quality conditions. The benchmarking framework supports system designers, software engineers, and application developers to select and investigate the behavior of communication protocols. Our benchmarking framework contributes to (i) show the impact of fluctuating network quality on communication, (ii) compare multiple protocols, protocol features, and protocol implementations, and (iii) analyze scalability, robustness, and dependability of clients, networks, and brokers in different scenarios. Our case study demonstrates the applicability of our framework to support the decision for the best-suited protocol in various scenarios.

@inproceedings{10.1007/978-3-030-92511-6_5, abstract = {Efficient and dependable communication is a highly relevant aspect for Internet of Things (IoT) systems in which tiny sensors, actuators, wearables, or other smart devices exchange messages. Various publish/subscribe protocols address the challenges of communication in IoT systems. The selection process of a suitable protocol should consider the communication behavior of the application, the protocol's performance, the resource requirements on the end device, and the network connection quality, as IoT environments often rely on wireless networks. Benchmarking is a common approach to evaluate and compare systems, considering the performance and aspects like dependability or security. In this paper, we present our IoT communication benchmarking framework ComBench for publish/subscribe protocols focusing on constrained networks with varying quality conditions. The benchmarking framework supports system designers, software engineers, and application developers to select and investigate the behavior of communication protocols. Our benchmarking framework contributes to (i) show the impact of fluctuating network quality on communication, (ii) compare multiple protocols, protocol features, and protocol implementations, and (iii) analyze scalability, robustness, and dependability of clients, networks, and brokers in different scenarios. Our case study demonstrates the applicability of our framework to support the decision for the best-suited protocol in various scenarios.}, address = {Cham}, author = {Herrnleben, Stefan and Leidinger, Maximilian and Lesch, Veronika and Prantl, Thomas and Grohmann, Johannes and Krupitzer, Christian and Kounev, Samuel}, booktitle = {Performance Evaluation Methodologies and Tools}, editor = {Zhao, Qianchuan and Xia, Li}, keywords = {myown}, pages = {72–92}, publisher = {Springer International Publishing}, title = {ComBench: A Benchmarking Framework for Publish/Subscribe Communication Protocols Under Network Limitations}, year = 2021 }
Dietz, K., Mühlhauser, M., Seufert, M., Gray, N., Hoßfeld, T., Herrmann, D.: Browser Fingerprinting: How to Protect Machine Learning Models and Data with Differential Privacy?. 1st International Workshop on Machine Learning in Networking (MaLeNe). , Lübeck, Germany (Virtual Conference) (2021).
- [ BibTeX ]
@inproceedings{info3-inproceedings-2021-16, address = {Lübeck, Germany (Virtual Conference)}, author = {Dietz, Katharina and Mühlhauser, Michael and Seufert, Michael and Gray, Nicholas and Hoßfeld, Tobias and Herrmann, Dominik}, booktitle = {1st International Workshop on Machine Learning in Networking (MaLeNe)}, keywords = {ucn}, month = 9, title = {Browser Fingerprinting: How to Protect Machine Learning Models and Data with Differential Privacy?}, year = 2021 }
Straesser, M.: Container Start Times: Empirical Analysis and Predictability. (2021).
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@presentation{straesser2021container, author = {Straesser, Martin}, keywords = {myown}, title = {Container Start Times: Empirical Analysis and Predictability}, year = 2021 }
Geiger, J., Cornelsen, S., Haunert, J.-H., Kindermann, P., Mchedlidze, T., N{\"o}llenburg, M., Okamoto, Y., Wolff, A.: ClusterSets: Optimizing Planar Clusters in Categorical Point Data. Comput. Graphics Forum. 40, 471–481 (2021).
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- [ DOI ]
@article{gchkmnow-coplc-EuroVis21, author = {Geiger, Jakob and Cornelsen, Sabine and Haunert, Jan-Henrik and Kindermann, Philipp and Mchedlidze, Tamara and N{\"o}llenburg, Martin and Okamoto, Yoshio and Wolff, Alexander}, journal = {Comput. Graphics Forum}, keywords = {myown}, number = 3, pages = {471–481}, title = {ClusterSets: Optimizing Planar Clusters in Categorical Point Data}, volume = 40, year = 2021 }
Chaplick, S., Kindermann, P., Klawitter, J., Rutter, I., Wolff, A.: Extending Partial Representations of Rectangular Duals with Given Contact Orientations. In: Calamoneri, T. und Cor{\’o}, F. (hrsg.) Proc. 12th International Conference on Algorithms and Complexity (CIAC’21). S. 340–353. Springer-Verlag (2021).
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@inproceedings{ckkrw-eprrd-CIAC21, author = {Chaplick, Steven and Kindermann, Philipp and Klawitter, Jonathan and Rutter, Ignaz and Wolff, Alexander}, booktitle = {Proc. 12th International Conference on Algorithms and Complexity (CIAC'21)}, editor = {Calamoneri, Tiziana and Cor{\'o}, Federico}, keywords = {myown}, pages = {340–353}, publisher = {Springer-Verlag}, series = {Lecture Notes in Computer Science}, title = {Extending Partial Representations of Rectangular Duals with Given Contact Orientations}, volume = 12701, year = 2021 }
Evans, W., Gethner, E., Spalding-Jamieson, J., Wolff, A.: Angle Covers: Algorithms and Complexity. Journal of Graph Algorithms \& Applications. 25, 643–661 (2021).
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@article{egsw-acac-JGAA21, author = {Evans, William and Gethner, Ellen and Spalding-Jamieson, Jack and Wolff, Alexander}, journal = {Journal of Graph Algorithms \& Applications}, keywords = {myown}, number = 2, pages = {643–661}, title = {Angle Covers: Algorithms and Complexity}, volume = 25, year = 2021 }
TrungKien, N., Hoang Anh, V., Dinh Phong, V., Ngoc Minh, N., Huu Thanh, N.: Machine Learning-based Service Function Chain over UAVs: Resource Profiling and Framework. 2021 31st International Telecommunication Networks and Applications Conference (ITNAC). , Sydney, Australia (2021).
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@inproceedings{info3-inproceedings-2021-21, address = {Sydney, Australia}, author = {TrungKien, Nguyen and Hoang Anh, Vu and Dinh Phong, Vu and Ngoc Minh, Nguyen and Huu Thanh, Nguyen}, booktitle = {2021 31st International Telecommunication Networks and Applications Conference (ITNAC)}, keywords = {myown}, month = 11, title = {Machine Learning-based Service Function Chain over UAVs: Resource Profiling and Framework}, year = 2021 }
Büttner, J.: Utilizing the Observer/Controller Architecture for a General Game AI. In: Tomforde, S. und Krupitzer, C. (hrsg.) Organic Computing: Doctoral Dissertation Colloquium 2021. S. 74–85. kassel university press (2021).
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@inbook{buttner2021utilizing, author = {Büttner, Johannes}, booktitle = {Organic Computing: Doctoral Dissertation Colloquium 2021}, editor = {Tomforde, Sven and Krupitzer, Christian}, keywords = {myown}, pages = {74–85}, publisher = {kassel university press}, title = {Utilizing the Observer/Controller Architecture for a General Game AI}, year = 2021 }
Arseneva, E., Kleist, L., Klemz, B., L{\"o}ffler, M., Schulz, A., Vogtenhuber, B., Wolff, A.: Adjacency Graphs of Polyhedral Surfaces. In: Buchin, K. und \’{E}ric {Colin de Verdi{\`e}re} (hrsg.) Proc. 37th Annu. Sympos. Comput. Geom. (SoCG’21). S. 11:1–11:17. Schloss Dagstuhl~-- Leibniz-Zentrum f{\"u}r Informatik (2021).
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@inproceedings{akklsvw-dgps-SoCG21, author = {Arseneva, Elena and Kleist, Linda and Klemz, Boris and L{\"o}ffler, Maarten and Schulz, Andr{\'e} and Vogtenhuber, Birgit and Wolff, Alexander}, booktitle = {Proc. 37th Annu. Sympos. Comput. Geom. (SoCG'21)}, editor = {Buchin, Kevin and \'{E}ric {Colin de Verdi{\`e}re}}, keywords = {realizability}, pages = {11:1–11:17}, publisher = {Schloss Dagstuhl – Leibniz-Zentrum f{\"u}r Informatik}, series = {LIPIcs}, title = {Adjacency Graphs of Polyhedral Surfaces}, volume = 189, year = 2021 }
Frank, F., Kaufmann, M., Kobourov, S., Mchedlidze, T., Pupyrev, S., Ueckerdt, T., Wolff, A.: Using the Metro-Map Metaphor for Drawing Hypergraphs. In: Bure\v{s}, T., Dondi, R., Gamper, J., Guerrini, G., Jurdzi{\’n}ski, T., Pahl, C., Sikora, F., und Wong, P. (hrsg.) Proc. 47th Int. Conf. Current Trends Theory \& Practice Comput. Sci. (SOFSEM’21). S. 361–372. Springer-Verlag (2021).
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@inproceedings{fkkmpuw-ummmdh-SOFSEM21, author = {Frank, Fabian and Kaufmann, Michael and Kobourov, Stephen and Mchedlidze, Tamara and Pupyrev, Sergey and Ueckerdt, Torsten and Wolff, Alexander}, booktitle = {Proc. 47th Int. Conf. Current Trends Theory \& Practice Comput. Sci. (SOFSEM'21)}, editor = {Bure\v{s}, Tom{\'a}\v{s} and Dondi, Riccardo and Gamper, Johann and Guerrini, Giovanna and Jurdzi{\'n}ski, Tomasz and Pahl, Claus and Sikora, Florian and Wong, Prudence}, keywords = {myown}, pages = {361–372}, publisher = {Springer-Verlag}, series = {Lecture Notes in Computer Science}, title = {Using the Metro-Map Metaphor for Drawing Hypergraphs}, volume = 12607, year = 2021 }
Foerster, K., Hein, R., Grafe, S., Latoschik, M.E., Wienrich, C.: Fostering Intercultural Competencies in Initial Teacher Education. Implementation of Educational Design Prototypes using a Social VR Environment. In: Bastiaens, T. (hrsg.) Proceedings of Innovate Learning Summit 2020 2021. S. 73–86. Association for the Advancement of Computing in Education (AACE), Online, United States (2021).
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The combination of globalization and digitalization emphasizes the importance of media-related and intercultural competencies of teacher educators and pre-service teachers. This article reports on the initial prototypical implementation of a pedagogical concept to foster such competencies of pre-service teachers. The proposed pedagogical concept utilizes a social VR framework since related work on the characteristics of VR indicate that this medium is particularly well suited for intercultural professional development processes. The development is integrated into a larger design-based-research approach that develops a theory-guided and empirically grounded professional development concept for teacher educators with a special focus on TETC 8. TETC provide a suitable competence framework capable of aligning both requirements for media-related as well as intercultural competencies. In an exploratory study with student teachers we designed...

@inproceedings{FoerHeinGraf2021ys, abstract = {The combination of globalization and digitalization emphasizes the importance of media-related and intercultural competencies of teacher educators and pre-service teachers. This article reports on the initial prototypical implementation of a pedagogical concept to foster such competencies of pre-service teachers. The proposed pedagogical concept utilizes a social VR framework since related work on the characteristics of VR indicate that this medium is particularly well suited for intercultural professional development processes. The development is integrated into a larger design-based-research approach that develops a theory-guided and empirically grounded professional development concept for teacher educators with a special focus on TETC 8. TETC provide a suitable competence framework capable of aligning both requirements for media-related as well as intercultural competencies. In an exploratory study with student teachers we designed...}, address = {Online, United States}, author = {Foerster, Kristina and Hein, Rebecca and Grafe, Silke and Latoschik, Marc Erich and Wienrich, Carolin}, booktitle = {Proceedings of Innovate Learning Summit 2020 2021}, editor = {Bastiaens, Theo}, keywords = {rhein}, month = {November}, pages = {73–86}, publisher = {Association for the Advancement of Computing in Education (AACE)}, title = {Fostering Intercultural Competencies in Initial Teacher Education. Implementation of Educational Design Prototypes using a Social VR Environment}, year = 2021 }
Davidson, P., Buckermann, F., Steininger, M., Krause, A., Hotho, A.: Semi-unsupervised Learning: An In-depth Parameter Analysis. In: Edelkamp, S., M{\"o}ller, R., und Rueckert, E. (hrsg.) KI 2021: Advances in Artificial Intelligence. S. 51–66. Springer International Publishing, Cham (2021).
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Creating datasets for supervised learning is a very challenging and expensive task, in which each input example has to be annotated with its expected output (e.g. object class). By combining unsupervised and semi-supervised learning, semi-unsupervised learning proposes a new paradigm for partially labeled datasets with additional unknown classes. In this paper we focus on a better understanding of this new learning paradigm and analyze the impact of the amount of labeled data, the number of augmented classes and the selection of hidden classes on the quality of prediction. Especially the number of augmented classes highly influences classification accuracy, which needs tuning for each dataset, since too few and too many augmented classes are detrimental to classifier performance. We also show that we can improve results on a large variety of datasets when using convolutional networks as feature extractors while applying output driven entropy regularization instead of a simple weight based L2 norm.

@inproceedings{10.1007/978-3-030-87626-5_5, abstract = {Creating datasets for supervised learning is a very challenging and expensive task, in which each input example has to be annotated with its expected output (e.g. object class). By combining unsupervised and semi-supervised learning, semi-unsupervised learning proposes a new paradigm for partially labeled datasets with additional unknown classes. In this paper we focus on a better understanding of this new learning paradigm and analyze the impact of the amount of labeled data, the number of augmented classes and the selection of hidden classes on the quality of prediction. Especially the number of augmented classes highly influences classification accuracy, which needs tuning for each dataset, since too few and too many augmented classes are detrimental to classifier performance. We also show that we can improve results on a large variety of datasets when using convolutional networks as feature extractors while applying output driven entropy regularization instead of a simple weight based L2 norm.}, address = {Cham}, author = {Davidson, Padraig and Buckermann, Florian and Steininger, Michael and Krause, Anna and Hotho, Andreas}, booktitle = {KI 2021: Advances in Artificial Intelligence}, editor = {Edelkamp, Stefan and M{\"o}ller, Ralf and Rueckert, Elmar}, keywords = {unsupervised}, pages = {51–66}, publisher = {Springer International Publishing}, title = {Semi-unsupervised Learning: An In-depth Parameter Analysis}, year = 2021 }
Dulny, A., Steininger, M., Lautenschlager, F., Krause, A., Hotho, A.: Evaluating the multi-task learning approach for land use regression modelling of air pollution. Journal of Physics: Conference Series. 1834, 012004 (2021).
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Air pollution has been linked to several health problems including heart disease, stroke and lung cancer. Modelling and analyzing this dependency requires reliable and accurate air pollutant measurements collected by stationary air monitoring stations. However, usually only a low number of such stations are present within a single city. To retrieve pollution concentrations for unmeasured locations, researchers rely on land use regression (LUR) models. Those models are typically developed for one pollutant only. However, as results in different areas have shown, modelling several related output variables through multi-task learning can improve the prediction results of the models significantly. In this work, we compared prediction results from single-task and multi-task learning multilayer perceptron models on measurements taken from the OpenSense dataset and the London Atmospheric Emissions Inventory dataset. LUR features were generated from OpenStreetMap using OpenLUR and used to train hard parameter sharing multilayer perceptron models. The results show multi-task learning with sufficient data significantly improves the performance of a LUR model.

@article{dulny2021evaluating, abstract = {Air pollution has been linked to several health problems including heart disease, stroke and lung cancer. Modelling and analyzing this dependency requires reliable and accurate air pollutant measurements collected by stationary air monitoring stations. However, usually only a low number of such stations are present within a single city. To retrieve pollution concentrations for unmeasured locations, researchers rely on land use regression (LUR) models. Those models are typically developed for one pollutant only. However, as results in different areas have shown, modelling several related output variables through multi-task learning can improve the prediction results of the models significantly. In this work, we compared prediction results from single-task and multi-task learning multilayer perceptron models on measurements taken from the OpenSense dataset and the London Atmospheric Emissions Inventory dataset. LUR features were generated from OpenStreetMap using OpenLUR and used to train hard parameter sharing multilayer perceptron models. The results show multi-task learning with sufficient data significantly improves the performance of a LUR model.}, author = {Dulny, Andrzej and Steininger, Michael and Lautenschlager, Florian and Krause, Anna and Hotho, Andreas}, journal = {Journal of Physics: Conference Series}, keywords = {myown}, month = {mar}, number = 1, organization = {IOP Publishing}, pages = {012004}, publisher = {{IOP} Publishing}, title = {Evaluating the multi-task learning approach for land use regression modelling of air pollution}, volume = 1834, year = 2021 }
Kern, F., Keser, T., Niebling, F., Latoschik, M.E.: Using Hand Tracking and Voice Commands to Physically Align Virtual Surfaces in AR for Handwriting and Sketching with HoloLens 2. 27th ACM Symposium on Virtual Reality Software and Technology. S. 1–3. Association for Computing Machinery, Osaka, Japan (2021).
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In this paper, we adapt an existing VR framework for handwriting and sketching on physically aligned virtual surfaces to AR environments using the Microsoft HoloLens 2. We demonstrate a multimodal input metaphor to control the framework’s calibration features using hand tracking and voice commands. Our technical evaluation of fingertip/surface accuracy and precision on physical tables and walls is in line with existing measurements on comparable hardware, albeit considerably lower compared to previous work using controller-based VR devices. We discuss design considerations and the benefits of our unified input metaphor suitable for controller tracking and hand tracking systems. We encourage extensions and replication by providing a publicly available reference implementation (https://go.uniwue.de/hci-otss-hololens).

@inproceedings{kern2021using, abstract = {In this paper, we adapt an existing VR framework for handwriting and sketching on physically aligned virtual surfaces to AR environments using the Microsoft HoloLens 2. We demonstrate a multimodal input metaphor to control the framework’s calibration features using hand tracking and voice commands. Our technical evaluation of fingertip/surface accuracy and precision on physical tables and walls is in line with existing measurements on comparable hardware, albeit considerably lower compared to previous work using controller-based VR devices. We discuss design considerations and the benefits of our unified input metaphor suitable for controller tracking and hand tracking systems. We encourage extensions and replication by providing a publicly available reference implementation (https://go.uniwue.de/hci-otss-hololens).}, address = {Osaka, Japan}, author = {Kern, Florian and Keser, Thore and Niebling, Florian and Latoschik, Marc Erich}, booktitle = {27th ACM Symposium on Virtual Reality Software and Technology}, keywords = {vilearn}, note = {Best poster award. 🏆}, pages = {1-3}, publisher = {Association for Computing Machinery}, series = {VRST '21}, title = {Using Hand Tracking and Voice Commands to Physically Align Virtual Surfaces in AR for Handwriting and Sketching with HoloLens 2}, year = 2021 }
Davidson, P., Steininger, M., Lautenschlager, F., Krause, A., Hotho, A.: Anomaly Detection in Beehives: An Algorithm Comparison, (2021).
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@misc{davidson2021anomaly, author = {Davidson, Padraig and Steininger, Michael and Lautenschlager, Florian and Krause, Anna and Hotho, Andreas}, keywords = {we4bee}, title = {Anomaly Detection in Beehives: An Algorithm Comparison}, year = 2021 }
Zehe, A., Konle, L., Guhr, S., Dümpelmann, L., Gius, E., Hotho, A., Jannidis, F., Kaufmann, L., Krug, M., Puppe, F., Reiter, N., Schreiber, A.: Shared Task on Scene Segmentation @ KONVENS 2021. Shared Task on Scene Segmentation @ KONVENS 2021. S. 1–21 (2021).
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@inproceedings{zehe2021shared, author = {Zehe, Albin and Konle, Leonard and Guhr, Svenja and Dümpelmann, Lea and Gius, Evelyn and Hotho, Andreas and Jannidis, Fotis and Kaufmann, Lucas and Krug, Markus and Puppe, Frank and Reiter, Nils and Schreiber, Annekea}, booktitle = {Shared Task on Scene Segmentation @ KONVENS 2021}, keywords = {stss}, pages = {1-21}, title = {Shared Task on Scene Segmentation @ KONVENS 2021}, year = 2021 }
Zehe, A., Konle, L., Dümpelmann, L., Gius, E., Hotho, A., Jannidis, F., Kaufmann, L., Krug, M., Puppe, F., Reiter, N., Schreiber, A., Wiedmer, N.: Detecting Scenes in Fiction: A new Segmentation Task. Proceedings of the 16th Conference of the {E}uropean Chapter of the Association for Computational Linguistics: Volume 1, Long Papers. ACL (2021).
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@inproceedings{zehe2021detecting, author = {Zehe, Albin and Konle, Leonard and Dümpelmann, Lea and Gius, Evelyn and Hotho, Andreas and Jannidis, Fotis and Kaufmann, Lucas and Krug, Markus and Puppe, Frank and Reiter, Nils and Schreiber, Annekea and Wiedmer, Nathalie}, booktitle = {Proceedings of the 16th Conference of the {E}uropean Chapter of the Association for Computational Linguistics: Volume 1, Long Papers}, keywords = {task}, publisher = {ACL}, title = {Detecting Scenes in Fiction: A new Segmentation Task}, year = 2021 }
Hoßfeld, T., Seufert, M., Naderi, B.: On Inter-Rater Reliability for Crowdsourced QoE. 13th International Conference on Quality of Multimedia Experience (QoMEX). , Montreal, Canada (Virtual Conference) (2021).
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@inproceedings{info3-inproceedings-2021-9, address = {Montreal, Canada (Virtual Conference)}, author = {Hoßfeld, Tobias and Seufert, Michael and Naderi, Babak}, booktitle = {13th International Conference on Quality of Multimedia Experience (QoMEX)}, keywords = {ucn}, month = 6, title = {On Inter-Rater Reliability for Crowdsourced QoE}, year = 2021 }
Heß, J., Karageorgos, P., Richter, T., Müller, B., Riedmann, A., Schaper, P., Lugrin, B.: Digitale Leseförderung: Konzeption und Evaluation der "Mobilen Leseförderung". Round Table-Session präsentiert auf der Online-Tagung der Fachgruppe Pädagogische Psychologie der Deutschen Gesellschaft für Psychologie (DGPs) (2021).
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@conference{hess2021digitale, author = {Heß, J. and Karageorgos, P. and Richter, T. and Müller, B. and Riedmann, A. and Schaper, P. and Lugrin, B.}, booktitle = {Round Table-Session präsentiert auf der Online-Tagung der Fachgruppe Pädagogische Psychologie der Deutschen Gesellschaft für Psychologie (DGPs)}, keywords = {schaper}, title = {Digitale Leseförderung: Konzeption und Evaluation der "Mobilen Leseförderung"}, year = 2021 }
Lugrin, B., Rehm, M.: Culture for Socially Interactive Agents. In: Lugrin, B., Pelachaud, C., und Traum, D. (hrsg.) The Handbook on Socially Interactive Agents – 20 Years of Research on Embodied Conversational Agents, Intelligent Virtual Agents, and Social Robotics, Volume 1: Methods, Behavior, Cognition. S. 463–494. ACM (2021).
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@incollection{Lugrin_2021, author = {Lugrin, Birgit and Rehm, Matthias}, booktitle = {The Handbook on Socially Interactive Agents – 20 Years of Research on Embodied Conversational Agents, Intelligent Virtual Agents, and Social Robotics, Volume 1: Methods, Behavior, Cognition}, editor = {Lugrin, Birgit and Pelachaud, Catherine and Traum, David}, keywords = {myown}, pages = {463-494}, publisher = {ACM}, title = {Culture for Socially Interactive Agents}, year = 2021 }
Fernes, D., Oberdörfer, S., Latoschik, M.E.: Recreating a Medieval Mill as a Virtual Learning Environment. 27th ACM Symposium on Virtual Reality Software and Technology (VRST ’21). ACM, Osaka, Japan (2021).
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@inproceedings{fernes2021recreating, address = {Osaka, Japan}, author = {Fernes, David and Oberdörfer, Sebastian and Latoschik, Marc Erich}, booktitle = {27th ACM Symposium on Virtual Reality Software and Technology (VRST ’21)}, keywords = {oberdoerfer}, month = {December}, publisher = {ACM}, title = {Recreating a Medieval Mill as a Virtual Learning Environment}, year = 2021 }
Orsolic, I., Seufert, M.: On Machine Learning based Video QoE Estimation Across Different Networks. 16th International Conference on Telecommunications (ConTEL), Best Paper Award. , Zagreb, Croatia (Virtual Conference) (2021).
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@inproceedings{info3-inproceedings-2021-10, address = {Zagreb, Croatia (Virtual Conference)}, author = {Orsolic, Irena and Seufert, Michael}, booktitle = {16th International Conference on Telecommunications (ConTEL), Best Paper Award}, keywords = {ucn}, month = 7, title = {On Machine Learning based Video QoE Estimation Across Different Networks}, year = 2021 }
Eismann, S., Bui, L., Grohmann, J., Abad, C., Herbst, N., Kounev, S.: Sizeless: Predicting the Optimal Size of Serverless Functions. Proceedings of the 22nd International MIDDLEWARE Conference. S. 248–259 (2021).
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Serverless functions are an emerging cloud computing paradigm that is being rapidly adopted by both industry and academia. In this cloud computing model, the provider opaquely handles resource management tasks such as resource provisioning, deployment, and auto-scaling. The only resource management task that developers are still in charge of is selecting how much resources are allocated to each worker instance. However, selecting the optimal size of serverless functions is quite challenging, so developers often neglect it despite its significant cost and performance benefits. Existing approaches aiming to automate serverless functions resource sizing require dedicated performance tests, which are time-consuming to implement and maintain. In this paper, we introduce an approach to predict the optimal resource size of a serverless function using monitoring data from a single resource size. As our approach does not require dedicated performance tests, it enables cloud providers to implement resource sizing on a platform level and automate the last resource management task associated with serverless functions. We evaluate our approach on four different serverless applications on AWS, where it predicts the execution time of the other memory sizes based on monitoring data for a single memory size with an average prediction error of 15.3%. Based on these predictions, it selects the optimal memory size for 79.0% of the serverless functions and the secondbest memory size for 12.3% of the serverless functions, which results in an average speedup of 39.7% while also decreasing average costs by 2.6%.

@inproceedings{eismann2021sizeless, abstract = {Serverless functions are an emerging cloud computing paradigm that is being rapidly adopted by both industry and academia. In this cloud computing model, the provider opaquely handles resource management tasks such as resource provisioning, deployment, and auto-scaling. The only resource management task that developers are still in charge of is selecting how much resources are allocated to each worker instance. However, selecting the optimal size of serverless functions is quite challenging, so developers often neglect it despite its significant cost and performance benefits. Existing approaches aiming to automate serverless functions resource sizing require dedicated performance tests, which are time-consuming to implement and maintain. In this paper, we introduce an approach to predict the optimal resource size of a serverless function using monitoring data from a single resource size. As our approach does not require dedicated performance tests, it enables cloud providers to implement resource sizing on a platform level and automate the last resource management task associated with serverless functions. We evaluate our approach on four different serverless applications on AWS, where it predicts the execution time of the other memory sizes based on monitoring data for a single memory size with an average prediction error of 15.3%. Based on these predictions, it selects the optimal memory size for 79.0% of the serverless functions and the secondbest memory size for 12.3% of the serverless functions, which results in an average speedup of 39.7% while also decreasing average costs by 2.6%.}, author = {Eismann, Simon and Bui, Long and Grohmann, Johannes and Abad, Cristina and Herbst, Nikolas and Kounev, Samuel}, booktitle = {Proceedings of the 22nd International MIDDLEWARE Conference}, keywords = {descartes}, note = {Best Student Paper Award, ACM Artifacts Evaluated — Functional}, pages = {248–259}, title = {Sizeless: Predicting the Optimal Size of Serverless Functions}, year = 2021 }
Wienrich, C., Komma, P., Vogt, S., Latoschik, M.E.: Spatial Presence in Mixed Realities--Considerations about the Concept, Measures, Design, and Experiments. Frontiers in Virtual Reality. 2, 141 (2021).
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Plenty of theories, models, measures, and investigations target the understanding of virtual presence, i.e., the sense of presence in immersive Virtual Reality (VR). Other varieties of the so-called eXtended Realities (XR), e.g., Augmented and Mixed Reality (AR and MR) incorporate immersive features to a lesser degree and continuously combine spatial cues from the real physical space and the simulated virtual space. This blurred separation questions the applicability of the accumulated knowledge about the similarities of virtual presence and presence occurring in other varieties of XR, and corresponding outcomes. The present work bridges this gap by analyzing the construct of presence in mixed realities (MR). To achieve this, the following presents (1) a short review of definitions, dimensions, and measurements of presence in VR, and (2) the state of the art views on MR. Additionally, we (3) derived a working definition of MR, extending the Milgram continuum. This definition is based on entities reaching from real to virtual manifestations at one time point. Entities possess different degrees of referential power, determining the selection of the frame of reference. Furthermore, we (4) identified three research desiderata, including research questions about the frame of reference, the corresponding dimension of transportation, and the dimension of realism in MR. Mainly the relationship between the main aspects of virtual presence of immersive VR, i.e., the place-illusion, and the plausibility-illusion, and of the referential power of MR entities are discussed regarding the concept, measures, and design of presence in MR. Finally, (5) we suggested an experimental setup to reveal the research heuristic behind experiments investigating presence in MR. The present work contributes to the theories and the meaning of and approaches to simulate and measure presence in MR. We hypothesize that research about essential underlying factors determining user experience (UX) in MR simulations and experiences is still in its infancy and hopes this article provides an encouraging starting point to tackle related questions.

@article{wienrichspatial, abstract = {Plenty of theories, models, measures, and investigations target the understanding of virtual presence, i.e., the sense of presence in immersive Virtual Reality (VR). Other varieties of the so-called eXtended Realities (XR), e.g., Augmented and Mixed Reality (AR and MR) incorporate immersive features to a lesser degree and continuously combine spatial cues from the real physical space and the simulated virtual space. This blurred separation questions the applicability of the accumulated knowledge about the similarities of virtual presence and presence occurring in other varieties of XR, and corresponding outcomes. The present work bridges this gap by analyzing the construct of presence in mixed realities (MR). To achieve this, the following presents (1) a short review of definitions, dimensions, and measurements of presence in VR, and (2) the state of the art views on MR. Additionally, we (3) derived a working definition of MR, extending the Milgram continuum. This definition is based on entities reaching from real to virtual manifestations at one time point. Entities possess different degrees of referential power, determining the selection of the frame of reference. Furthermore, we (4) identified three research desiderata, including research questions about the frame of reference, the corresponding dimension of transportation, and the dimension of realism in MR. Mainly the relationship between the main aspects of virtual presence of immersive VR, i.e., the place-illusion, and the plausibility-illusion, and of the referential power of MR entities are discussed regarding the concept, measures, and design of presence in MR. Finally, (5) we suggested an experimental setup to reveal the research heuristic behind experiments investigating presence in MR. The present work contributes to the theories and the meaning of and approaches to simulate and measure presence in MR. We hypothesize that research about essential underlying factors determining user experience (UX) in MR simulations and experiences is still in its infancy and hopes this article provides an encouraging starting point to tackle related questions.}, author = {Wienrich, Carolin and Komma, Philipp and Vogt, Stephanie and Latoschik, Marc Erich}, editor = {Skarbez, Richard}, journal = {Frontiers in Virtual Reality}, keywords = {myown}, pages = 141, publisher = {Frontiers}, title = {Spatial Presence in Mixed Realities–Considerations about the Concept, Measures, Design, and Experiments}, volume = 2, year = 2021 }
Qi, Y., Bruch, D., Krop, P., Herrmann, M.J., Latoschik, M.E., Deckert, J., Hein, G.: Social buffering of human fear is shaped by gender, social concern and the presence of real vs virtual agents. Translational psychiatry. 11, 1–10 (2021).
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The presence of a partner can attenuate physiological fear responses, a phenomenon known as social buffering. However, not all individuals are equally sociable. Here we investigated whether social buffering of fear is shaped by sensitivity to social anxiety (social concern) and whether these effects are different in females and males. We collected skin conductance responses (SCRs) and affect ratings of female and male participants when they experienced aversive and neutral sounds alone (alone treatment) or in the presence of an unknown person of the same gender (social treatment). Individual differences in social concern were assessed based on a well-established questionnaire. Our results showed that social concern had a stronger effect on social buffering in females than in males. The lower females scored on social concern, the stronger the SCRs reduction in the social compared to the alone treatment. The effect of social concern on social buffering of fear in females disappeared if participants were paired with a virtual agent instead of a real person. Together, these results showed that social buffering of human fear is shaped by gender and social concern. In females, the presence of virtual agents can buffer fear, irrespective of individual differences in social concern. These findings specify factors that shape the social modulation of human fear, and thus might be relevant for the treatment of anxiety disorders.

@article{qi2021social, abstract = {The presence of a partner can attenuate physiological fear responses, a phenomenon known as social buffering. However, not all individuals are equally sociable. Here we investigated whether social buffering of fear is shaped by sensitivity to social anxiety (social concern) and whether these effects are different in females and males. We collected skin conductance responses (SCRs) and affect ratings of female and male participants when they experienced aversive and neutral sounds alone (alone treatment) or in the presence of an unknown person of the same gender (social treatment). Individual differences in social concern were assessed based on a well-established questionnaire. Our results showed that social concern had a stronger effect on social buffering in females than in males. The lower females scored on social concern, the stronger the SCRs reduction in the social compared to the alone treatment. The effect of social concern on social buffering of fear in females disappeared if participants were paired with a virtual agent instead of a real person. Together, these results showed that social buffering of human fear is shaped by gender and social concern. In females, the presence of virtual agents can buffer fear, irrespective of individual differences in social concern. These findings specify factors that shape the social modulation of human fear, and thus might be relevant for the treatment of anxiety disorders.}, author = {Qi, Yanyan and Bruch, Doroth{\'e}e and Krop, Philipp and Herrmann, Martin J and Latoschik, Marc Erich and Deckert, J{\"u}rgen and Hein, Grit}, journal = {Translational psychiatry}, keywords = {myown}, number = 1, pages = {1–10}, publisher = {Nature Publishing Group}, title = {Social buffering of human fear is shaped by gender, social concern and the presence of real vs virtual agents}, volume = 11, year = 2021 }
Mußmann, M., Truman, S., von Mammen, S.: Game-Ready Inventory Systems for Virtual Reality. IEEE COG 2021. 2021, (2021).
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@article{mussmann2021gameready, author = {Mußmann, Marc and Truman, Samuel and von Mammen, Sebastian}, journal = {IEEE COG 2021}, keywords = {via-vr}, note = {Best student paper award 🏆}, title = {Game-Ready Inventory Systems for Virtual Reality}, volume = 2021, year = 2021 }
Schreiner, L., von Mammen, S.: Modding Support of Game Engines. The 16th International Conference on the Foundations of Digital Games (FDG) 2021. Association for Computing Machinery, Montreal, QC, Canada (2021).
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This paper aims at showing how different game engines support modding. To this end, the concepts of modding and game engines alongside their historical evolution are introduced first. Additionally, some well-known game engines and mods are presented, and their unique features are described. Further, the effects of using game engines and those that modding has on games, developers, and players are laid out. Particular focus is placed on the effects on competitive games. These effects include an enhanced lifespan for games and the requirement for more development effort. Finally, the modding-support of selected game engines is illustrated and compared with each other. These engines are the id Tech engine(s), Unreal Engine, the Source engine, and Unity. The paper is then concluded with an outlook on future research possibilities and recommendations to developers.

@inproceedings{10.1145/3472538.3472574, abstract = {This paper aims at showing how different game engines support modding. To this end, the concepts of modding and game engines alongside their historical evolution are introduced first. Additionally, some well-known game engines and mods are presented, and their unique features are described. Further, the effects of using game engines and those that modding has on games, developers, and players are laid out. Particular focus is placed on the effects on competitive games. These effects include an enhanced lifespan for games and the requirement for more development effort. Finally, the modding-support of selected game engines is illustrated and compared with each other. These engines are the id Tech engine(s), Unreal Engine, the Source engine, and Unity. The paper is then concluded with an outlook on future research possibilities and recommendations to developers.}, address = {New York, NY, USA}, author = {Schreiner, Lukas and von Mammen, Sebastian}, booktitle = {The 16th International Conference on the Foundations of Digital Games (FDG) 2021}, keywords = {myown}, publisher = {Association for Computing Machinery}, series = {FDG'21}, title = {Modding Support of Game Engines}, year = 2021 }
BenSiSaid, K., Ababou, N., Ababou, A., Roth, D., von Mammen, S.: Tracking rower motion without on-body sensors using an instrumented machine and an artificial neural network. Proceedings of the Institution of Mechanical Engineers, Part P: Journal of Sports Engineering and Technology. (2021).
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- [ URL ]
@article{bensisaid2021tracking, author = {BenSiSaid, Karim and Ababou, Noureddine and Ababou, Amina and Roth, Daniel and von Mammen, Sebastian}, journal = {Proceedings of the Institution of Mechanical Engineers, Part P: Journal of Sports Engineering and Technology}, keywords = {myown}, publisher = {SAGE Publications Sage UK: London, England}, title = {Tracking rower motion without on-body sensors using an instrumented machine and an artificial neural network}, year = 2021 }
Kern, F., Popp, M., Kullmann, P., Ganal, E., Latoschik, M.E.: 3D Printing an Accessory Dock for XR Controllers and its Exemplary Use as XR Stylus. 27th ACM Symposium on Virtual Reality Software and Technology. S. 1–3. Association for Computing Machinery, Osaka, Japan (2021).
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- [ URL ]
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This article introduces the accessory dock, a 3D printed multipurpose extension for consumer-grade XR controllers that enables flexible mounting of self-made and commercial accessories. The uniform design of our concept opens new opportunities for XR systems being used for more diverse purposes, e.g., researchers and practitioners could use and compare arbitrary XR controllers within their experiments while ensuring access to buttons and battery housing. As a first example, we present a stylus tip accessory to build an XR Stylus, which can be directly used with frameworks for handwriting, sketching, and UI interaction on physically aligned virtual surfaces. For new XR controllers, we provide instructions on how to adjust the accessory dock to the controller’s form factor. A video tutorial for the construction and the source files for 3D printing are publicly available for reuse, replication, and extension (https://go.uniwue.de/hci-otss-accessory-dock).

@inproceedings{kern2021printing, abstract = {This article introduces the accessory dock, a 3D printed multipurpose extension for consumer-grade XR controllers that enables flexible mounting of self-made and commercial accessories. The uniform design of our concept opens new opportunities for XR systems being used for more diverse purposes, e.g., researchers and practitioners could use and compare arbitrary XR controllers within their experiments while ensuring access to buttons and battery housing. As a first example, we present a stylus tip accessory to build an XR Stylus, which can be directly used with frameworks for handwriting, sketching, and UI interaction on physically aligned virtual surfaces. For new XR controllers, we provide instructions on how to adjust the accessory dock to the controller’s form factor. A video tutorial for the construction and the source files for 3D printing are publicly available for reuse, replication, and extension (https://go.uniwue.de/hci-otss-accessory-dock).}, address = {Osaka, Japan}, author = {Kern, Florian and Popp, Matthias and Kullmann, Peter and Ganal, Elisabeth and Latoschik, Marc Erich}, booktitle = {27th ACM Symposium on Virtual Reality Software and Technology}, keywords = {vilearn}, pages = {1-3}, publisher = {Association for Computing Machinery}, series = {VRST '21}, title = {3D Printing an Accessory Dock for XR Controllers and its Exemplary Use as XR Stylus}, year = 2021 }
Seufert, A., Wamser, F., Wunderer, S., Hall, A., Hoßfeld, T.: Trust but Verify: Crowdsourced Mobile Network Measurements and Statistical Validity Measures. 2021 Joint European Conference on Networks and Communications & 6G Summit (EuCNC/6G Summit). , Porto, Portugal (virtual conference) (2021).
- [ Abstract ]
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Network operators, regulators, and big data companies use crowdsourced measurements to study the performance of mobile networks on a large scale. Such a type of measurement is defined as the collection and processing of data measured by the crowd, here the crowd of mobile subscribers. Crowdsourced network measurements make it relatively easy and inexpensive to obtain large amounts of network data that also reflect the quality actually received by the end user. However, this measurement method also involves some uncertainties, since, for example, it is not possible to precisely control when, where and with which devices measurements are taken. Thus, there is a trade-off between the reliability of the individual measurement and the scope of the measurements. Therefore, how data of this type is analyzed is particularly important in order to obtain valid results. To address this issue, our paper defines concepts and guidelines for analyzing the validity of crowdsourced mobile network measurements. In particular, we address precision, for example the number of measurements needed to make valid statements, and also representativeness, for example the spatial and temporal distribution of the data. In addition to the formal definition of these two aspects, we illustrate the issue and possible evaluation approaches with the help of an extensive example data set. This data set consists of more than 11.7M crowdsourced mobile measurements from all over France, measured by a commercial mobile data provider. In the end, we provide an evaluation guideline and two possible use cases.

@inproceedings{info3-inproceedings-2021-11, abstract = {Network operators, regulators, and big data companies use crowdsourced measurements to study the performance of mobile networks on a large scale. Such a type of measurement is defined as the collection and processing of data measured by the crowd, here the crowd of mobile subscribers. Crowdsourced network measurements make it relatively easy and inexpensive to obtain large amounts of network data that also reflect the quality actually received by the end user. However, this measurement method also involves some uncertainties, since, for example, it is not possible to precisely control when, where and with which devices measurements are taken. Thus, there is a trade-off between the reliability of the individual measurement and the scope of the measurements. Therefore, how data of this type is analyzed is particularly important in order to obtain valid results. To address this issue, our paper defines concepts and guidelines for analyzing the validity of crowdsourced mobile network measurements. In particular, we address precision, for example the number of measurements needed to make valid statements, and also representativeness, for example the spatial and temporal distribution of the data. In addition to the formal definition of these two aspects, we illustrate the issue and possible evaluation approaches with the help of an extensive example data set. This data set consists of more than 11.7M crowdsourced mobile measurements from all over France, measured by a commercial mobile data provider. In the end, we provide an evaluation guideline and two possible use cases.}, address = {Porto, Portugal (virtual conference)}, author = {Seufert, Anika and Wamser, Florian and Wunderer, Stefan and Hall, Andrew and Hoßfeld, Tobias}, booktitle = {2021 Joint European Conference on Networks and Communications & 6G Summit (EuCNC/6G Summit)}, keywords = {can}, month = 6, title = {Trust but Verify: Crowdsourced Mobile Network Measurements and Statistical Validity Measures}, year = 2021 }
Casas, P., Wassermann, S., Wehner, N., Seufert, M., Schüler, J., Hoßfeld, T.: Mobile Web and App QoE Monitoring for ISPs - from Encrypted Traffic to Speed Index through Machine Learning. 13th Wireless and Mobile Networking Conference (WMNC), Best Paper Award. , Montreal, Canada (Virtual Conference) (2021).
- [ BibTeX ]
@inproceedings{info3-inproceedings-2021-17, address = {Montreal, Canada (Virtual Conference)}, author = {Casas, Pedro and Wassermann, Sarah and Wehner, Nikolas and Seufert, Michael and Schüler, Joshua and Hoßfeld, Tobias}, booktitle = {13th Wireless and Mobile Networking Conference (WMNC), Best Paper Award}, keywords = {ucn}, month = 10, title = {Mobile Web and App QoE Monitoring for ISPs - from Encrypted Traffic to Speed Index through Machine Learning}, year = 2021 }
Steinhaeusser, S.C., Schaper, P., Lugrin, B.: Comparing a Robotic Storyteller versus Audio Book with Integration of Sound Effects and Background Music. In: Bethel, C., Paiva, A., Broadbent, E., Feil-Seifer, D., und Szafir, D. (hrsg.) Companion of the 2021 ACM/IEEE International Conference on Human-Robot Interaction (HRI 2021). ACM (2021).
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- [ URL ]
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@inproceedings{Steinhaeusser_2021, author = {Steinhaeusser, Sophia C. and Schaper, Philipp and Lugrin, Birgit}, booktitle = {Companion of the 2021 ACM/IEEE International Conference on Human-Robot Interaction (HRI 2021)}, editor = {Bethel, Cindy and Paiva, Ana and Broadbent, Elizabeth and Feil-Seifer, David and Szafir, Daniel}, keywords = {storyteller}, publisher = {ACM}, title = {Comparing a Robotic Storyteller versus Audio Book with Integration of Sound Effects and Background Music}, year = 2021 }
Grigorjew, A., Seufert, M., Wehner, N., Hofmann, J., Hoßfeld, T.: ML-Assisted Latency Assignments in Time-Sensitive Networking. IFIP/IEEE International Symposium on Integrated Network Management (IM 2021). , Bordeaux, France (Virtual Conference) (2021).
- [ Abstract ]
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Recent developments in industrial automation and invehicle communication have raised the requirements of real-time networking. Bus systems that were traditionally deployed in these fields cannot provide sufficient bandwidth and are now shifting towards Ethernet for their real-time communication needs. In this field, standardization efforts from the IEEE and the IETF have developed new data plane mechanisms such as shapers and schedulers, as well as control plane mechanisms such as reservation protocols to support their new requirements. However, their implementation and their optimal configuration remain an important factor for their efficiency. This work presents a machine learning framework that takes on the configuration task. Four different models are trained for the configuration of per-hop latency guarantees in a distributed resource reservation process and compared with respect to their real-time traffic capacity. The evaluation shows that all models provide good configurations for the provided scenarios, but more importantly, they represent a first step for a semi-automated configuration of parameters in Time-Sensitive Networking.

@inproceedings{info3-inproceedings-2021-2, abstract = {Recent developments in industrial automation and invehicle communication have raised the requirements of real-time networking. Bus systems that were traditionally deployed in these fields cannot provide sufficient bandwidth and are now shifting towards Ethernet for their real-time communication needs. In this field, standardization efforts from the IEEE and the IETF have developed new data plane mechanisms such as shapers and schedulers, as well as control plane mechanisms such as reservation protocols to support their new requirements. However, their implementation and their optimal configuration remain an important factor for their efficiency. This work presents a machine learning framework that takes on the configuration task. Four different models are trained for the configuration of per-hop latency guarantees in a distributed resource reservation process and compared with respect to their real-time traffic capacity. The evaluation shows that all models provide good configurations for the provided scenarios, but more importantly, they represent a first step for a semi-automated configuration of parameters in Time-Sensitive Networking.}, address = {Bordeaux, France (Virtual Conference)}, author = {Grigorjew, Alexej and Seufert, Michael and Wehner, Nikolas and Hofmann, Jan and Hoßfeld, Tobias}, booktitle = {IFIP/IEEE International Symposium on Integrated Network Management (IM 2021)}, keywords = {kikdin}, month = 5, title = {ML-Assisted Latency Assignments in Time-Sensitive Networking}, year = 2021 }
Hotho, A., Blomqvist, E., Dietze, S., Fokoue, A., Ding, Y., Barnaghi, P.M., Haller, A., Dragoni, M., Alani, H. hrsg.: The Semantic Web - {ISWC} 2021 - 20th International Semantic Web Conference, {ISWC} 2021, Virtual Event, October 24-28, 2021, Proceedings. Springer (2021).
- [ BibTeX ]
- [ URL ]
- [ DOI ]
@proceedings{DBLP:conf/semweb/2021, editor = {Hotho, Andreas and Blomqvist, Eva and Dietze, Stefan and Fokoue, Achille and Ding, Ying and Barnaghi, Payam M. and Haller, Armin and Dragoni, Mauro and Alani, Harith}, keywords = {web}, publisher = {Springer}, series = {Lecture Notes in Computer Science}, title = {The Semantic Web - {ISWC} 2021 - 20th International Semantic Web Conference, {ISWC} 2021, Virtual Event, October 24-28, 2021, Proceedings}, volume = 12922, year = 2021 }
Ring, M., Schlör, D., Wunderlich, S., Landes, D., Hotho, A.: Malware detection on windows audit logs using LSTMs. Computers & Security. 109, 102389 (2021).
- [ Abstract ]
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Malware is a constant threat and is continuously evolving. Security systems try to keep up with the constant change. One challenge that arises is the large amount of logs generated on an operating system and the need to clarify which information contributes to the detection of possible malware. This work aims at the detection of malware using neural networks based on Windows audit log events. Neural networks can only process continuous data, but Windows audit logs are sequential and textual data. To address these challenges, we extract features out of the audit log events and use LSTMs to capture sequential effects. We create different subsets of features and analyze the effects of additional information. Features describe for example the action-type of windows audit log events, process names or target files that are accessed. Textual features are represented either as one-hot encoding or embedding representation, for which we compare three different approaches for representation learning. Effects of different feature subsets and representations are evaluated on a publicly available data set. Results indicate that using additional information improves the performance of the LSTM-model. While different representations lead to similar classification results, analysis of the latent space shows differences more precisely where FastText seems to be the most promising representation.

@article{RING2021102389, abstract = {Malware is a constant threat and is continuously evolving. Security systems try to keep up with the constant change. One challenge that arises is the large amount of logs generated on an operating system and the need to clarify which information contributes to the detection of possible malware. This work aims at the detection of malware using neural networks based on Windows audit log events. Neural networks can only process continuous data, but Windows audit logs are sequential and textual data. To address these challenges, we extract features out of the audit log events and use LSTMs to capture sequential effects. We create different subsets of features and analyze the effects of additional information. Features describe for example the action-type of windows audit log events, process names or target files that are accessed. Textual features are represented either as one-hot encoding or embedding representation, for which we compare three different approaches for representation learning. Effects of different feature subsets and representations are evaluated on a publicly available data set. Results indicate that using additional information improves the performance of the LSTM-model. While different representations lead to similar classification results, analysis of the latent space shows differences more precisely where FastText seems to be the most promising representation.}, author = {Ring, Markus and Schlör, Daniel and Wunderlich, Sarah and Landes, Dieter and Hotho, Andreas}, journal = {Computers & Security}, keywords = {myown}, pages = 102389, title = {Malware detection on windows audit logs using LSTMs}, volume = 109, year = 2021 }
Dulny, A., Hotho, A., Krause, A.: NeuralPDE: Modelling Dynamical Systems from Data, http://arxiv.org/abs/2111.07671, (2021).
- [ Abstract ]
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Many physical processes such as weather phenomena or fluid mechanics are governed by partial differential equations (PDEs). Modelling such dynamical systems using Neural Networks is an emerging research field. However, current methods are restricted in various ways: they require prior knowledge about the governing equations, and are limited to linear or first-order equations. In this work we propose NeuralPDE, a model which combines convolutional neural networks (CNNs) with differentiable ODE solvers to model dynamical systems. We show that the Method of Lines used in standard PDE solvers can be represented using convolutions which makes CNNs the natural choice to parametrize arbitrary PDE dynamics. Our model can be applied to any data without requiring any prior knowledge about the governing PDE. We evaluate NeuralPDE on datasets generated by solving a wide variety of PDEs, covering higher orders, non-linear equations and multiple spatial dimensions.

@misc{dulny2021neuralpde, abstract = {Many physical processes such as weather phenomena or fluid mechanics are governed by partial differential equations (PDEs). Modelling such dynamical systems using Neural Networks is an emerging research field. However, current methods are restricted in various ways: they require prior knowledge about the governing equations, and are limited to linear or first-order equations. In this work we propose NeuralPDE, a model which combines convolutional neural networks (CNNs) with differentiable ODE solvers to model dynamical systems. We show that the Method of Lines used in standard PDE solvers can be represented using convolutions which makes CNNs the natural choice to parametrize arbitrary PDE dynamics. Our model can be applied to any data without requiring any prior knowledge about the governing PDE. We evaluate NeuralPDE on datasets generated by solving a wide variety of PDEs, covering higher orders, non-linear equations and multiple spatial dimensions.}, author = {Dulny, Andrzej and Hotho, Andreas and Krause, Anna}, keywords = {pde}, note = {cite arxiv:2111.07671}, title = {NeuralPDE: Modelling Dynamical Systems from Data}, year = 2021 }
Büttner, J., Von Mammen, S.: Training a Reinforcement Learning Agent based on XCS in a Competitive Snake Environment. 2021 IEEE Conference on Games (CoG). S. 1–5 (2021).
- [ BibTeX ]
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@inproceedings{Buttner:2021aa, author = {Büttner, Johannes and Von Mammen, Sebastian}, booktitle = {2021 IEEE Conference on Games (CoG)}, keywords = {myown}, pages = {1-5}, title = {Training a Reinforcement Learning Agent based on XCS in a Competitive Snake Environment}, year = 2021 }
Ripka, G., Grafe, S., Latoschik, M.E.: Mapping pre-service teachers’ TPACK development using a social virtual reality and a video-conferencing system. In: Bastiaens, T. (hrsg.) Proceedings of Innovate Learning Summit 2021. S. 145–159. Association for the Advancement of Computing in Education (AACE) (2021).
- [ Abstract ]
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Social VR's characteristics, by offering authentic learning environments that enable interaction remotely and synchronously and permit learning experiences that affect learners in a multi-sensory way, offer great potential for teaching and learning processes. However, concerning its use to promote pre-service teachers' TPACK in initial teacher education, there remains a research desideratum. In this context, this exploratory study addressed the following research question: How did pre-service teachers' TPACK develop using a social VR learning environment prototype in comparison to a video conferencing platform throughout a semester? Following a design-based research approach, an action-oriented pedagogical concept for teaching and learning in social VR was designed and implemented for initial teacher education at a German university with a convenience sample of 14 participants. The lesson plans were collected and analyzed with the help of Epistemic Network Analysis (Shaffer, 2017) at three points of time during the semester and the GATI reflection process (Krauskopf et al., 2018). Further, 14 GATI diagrams gave insights into pre-service teachers' self-estimated TPACK. As the results indicate, pre-service students constructed more complex mental models of TPACK in social VR compared to the video conferencing platform, indicating that more interrelations between knowledge domains could be constructed by planning and designing VR-integrated lesson plans.

@inproceedings{gabrielaripka, abstract = {Social VR's characteristics, by offering authentic learning environments that enable interaction remotely and synchronously and permit learning experiences that affect learners in a multi-sensory way, offer great potential for teaching and learning processes. However, concerning its use to promote pre-service teachers' TPACK in initial teacher education, there remains a research desideratum. In this context, this exploratory study addressed the following research question: How did pre-service teachers' TPACK develop using a social VR learning environment prototype in comparison to a video conferencing platform throughout a semester? Following a design-based research approach, an action-oriented pedagogical concept for teaching and learning in social VR was designed and implemented for initial teacher education at a German university with a convenience sample of 14 participants. The lesson plans were collected and analyzed with the help of Epistemic Network Analysis (Shaffer, 2017) at three points of time during the semester and the GATI reflection process (Krauskopf et al., 2018). Further, 14 GATI diagrams gave insights into pre-service teachers' self-estimated TPACK. As the results indicate, pre-service students constructed more complex mental models of TPACK in social VR compared to the video conferencing platform, indicating that more interrelations between knowledge domains could be constructed by planning and designing VR-integrated lesson plans.}, author = {Ripka, Gabriela and Grafe, Silke and Latoschik, Marc Erich}, booktitle = {Proceedings of Innovate Learning Summit 2021}, editor = {Bastiaens, T.}, keywords = {myown}, organization = {Association for the Advancement of Computing in Education (AACE)}, pages = {145-159}, title = {Mapping pre-service teachers' TPACK development using a social virtual reality and a video-conferencing system}, year = 2021 }
Grohmann, J., Straesser, M., Chalbani, A., Eismann, S., Arian, Y., Herbst, N., Peretz, N., Kounev, S.: SuanMing: Explainable Prediction of Performance Degradations in Microservice Applications. Proceedings of the 12th ACM/SPEC International Conference on Performance Engineering (ICPE). ACM, New York, NY, USA (2021).
- [ Abstract ]
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- [ URL ]
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Application performance management (APM) tools are useful to observe the performance properties of an application during production. However, APM is normally purely reactive, that is, it can only report about current or past performance degradation. Although some approaches capable of predictive application monitoring have been proposed, they can only report a predicted degradation but cannot explain its root-cause, making it hard to prevent the expected degradation. In this paper, we present SuanMing---a framework for predicting performance degradation of microservice applications running in cloud environments. SuanMing is able to predict future root causes for anticipated performance degradations and therefore aims at preventing performance degradations before they actually occur. We evaluate SuanMing on two realistic microservice applications, TeaStore and TrainTicket, and we show that our approach is able to predict and pinpoint performance degradations with an accuracy of over 90\%.

@inproceedings{GrStChEiArHePeKo2021-ICPE, abstract = {Application performance management (APM) tools are useful to observe the performance properties of an application during production. However, APM is normally purely reactive, that is, it can only report about current or past performance degradation. Although some approaches capable of predictive application monitoring have been proposed, they can only report a predicted degradation but cannot explain its root-cause, making it hard to prevent the expected degradation. In this paper, we present SuanMing—a framework for predicting performance degradation of microservice applications running in cloud environments. SuanMing is able to predict future root causes for anticipated performance degradations and therefore aims at preventing performance degradations before they actually occur. We evaluate SuanMing on two realistic microservice applications, TeaStore and TrainTicket, and we show that our approach is able to predict and pinpoint performance degradations with an accuracy of over 90\%.}, address = {New York, NY, USA}, author = {Grohmann, Johannes and Straesser, Martin and Chalbani, Avi and Eismann, Simon and Arian, Yair and Herbst, Nikolas and Peretz, Noam and Kounev, Samuel}, booktitle = {Proceedings of the 12th ACM/SPEC International Conference on Performance Engineering (ICPE)}, keywords = {myown}, month = {April}, note = {Acceptance Rate: 29%}, organization = {ACM}, title = {SuanMing: Explainable Prediction of Performance Degradations in Microservice Applications}, year = 2021 }
Wankerl, S., Dulny, A., Götz, G., Hotho, A.: Learning Mathematical Relations Using Deep Tree Models. 2021 20th IEEE International Conference on Machine Learning and Applications (ICMLA). S. 1681–1687 (2021).