Hi there!

I’m a second year PhD Student in Computer Science at the University of St. Gallen in Switzerland in the lab for Interactions- and Communication-based Systems.

My research combines the following areas:

  • Mixed Reality
  • Ubiquitous Computing
  • Personalization
  • Privacy
  • Algorithms and Society
  • Computer Vision
  • Technology Acceptance

For updates on what I’m doing, have a look at the Publications of my colleagues and me, follow me on the Fediverse: https://hci.social/@jannis, or contact me via email: jannisrene.strecker@unisg.ch. 😀

📑 Recent Publications

NeighboAR: Efficient Object Retrieval using Proximity-and Gaze-based Object Grouping with an AR System

In

Proceedings of the ACM on Human-Computer Interaction (ETRA)

Date

June 04, 2024

Authors

Aleksandar Slavuljica, Kenan Bektaş, Jannis Strecker, and Simon Mayer

Abstract

Humans only recognize a few items in a scene at once and memorize three to seven items in the short term. Such limitations can be mitigated using cognitive offloading (e.g., sticky notes, digital reminders). We studied whether a gaze-enabled Augmented Reality (AR) system could facilitate cognitive offloading and improve object retrieval performance. To this end, we developed NeighboAR, which detects objects in a user's surroundings and generates a graph that stores object proximity relationships and user's gaze dwell times for each object. In a controlled experiment, we asked N=17 participants to inspect randomly distributed objects and later recall the position of a given target object. Our results show that displaying the target together with the proximity object with the longest user gaze dwell time helps recalling the position of the target. Specifically, NeighboAR significantly reduces the retrieval time by 33%, number of errors by 71%, and perceived workload by 10%.

Text Reference

Aleksandar Slavuljica, Kenan Bektaş, Jannis Strecker, and Simon Mayer. 2024. NeighboAR: Efficient Object Retrieval using Proximity- and Gaze-based Object Grouping with an AR System. Proc. ACM Hum.-Comput. Interact. 8, ETRA, Article 225 (May 2024), 19 pages. https://doi.org/10.1145/3655599

BibTex Reference
@inproceedings{slavuljica2024,
author = {Slavuljica, Aleksandar and Bekta\c{s}, Kenan and Strecker, Jannis and Mayer, Simon},
title = {NeighboAR: Efficient Object Retrieval using Proximity-and Gaze-based Object Grouping with an AR System},
year = {2024},
publisher = {Association for Computing Machinery},
address = {New York, NY, USA},
url = {https://doi.org/10.1145/3655599},
doi = {10.1145/3655599},
abstract = {Humans only recognize a few items in a scene at once and memorize three to seven items in the short term. Such limitations can be mitigated using cognitive offloading (e.g., sticky notes, digital reminders). We studied whether a gaze-enabled Augmented Reality (AR) system could facilitate cognitive offloading and improve object retrieval performance. To this end, we developed NeighboAR, which detects objects in a user's surroundings and generates a graph that stores object proximity relationships and user's gaze dwell times for each object. In a controlled experiment, we asked N=17 participants to inspect randomly distributed objects and later recall the position of a given target object. Our results show that displaying the target together with the proximity object with the longest user gaze dwell time helps recalling the position of the target. Specifically, NeighboAR significantly reduces the retrieval time by 33%, number of errors by 71%, and perceived workload by 10%.},
booktitle = {Proc. ACM Hum.-Comput. Interact.},
volume = {8}
issue = {ETRA},
articleno = {225},
numpages = {19},
keywords = {augmented reality, cognitive offloading, eye tracking, object detection,human augmentation, mixed reality, working memory, visual search},
}

Link to Published Paper Download Paper Link to Code

ShoppingCoach: Using Diminished Reality to Prevent Unhealthy Food Choices in an Offline Supermarket Scenario

In

Extended Abstracts of the CHI Conference on Human Factors in Computing Systems (CHI EA ’24)

Date

May 11, 2024

Authors

Jannis Strecker, Jing Wu, Kenan Bektaş, Conrad Vaslin, and Simon Mayer

Abstract

Non-communicable diseases, such as obesity and diabetes, have a significant global impact on health outcomes. While governments worldwide focus on promoting healthy eating, individuals still struggle to follow dietary recommendations. Augmented Reality (AR) might be a useful tool to emphasize specific food products at the point of purchase. However, AR may also add visual clutter to an already complex supermarket environment. Instead, reducing the visual prevalence of unhealthy food products through Diminished Reality (DR) could be a viable alternative: We present Shopping-Coach, a DR prototype that identifies supermarket food products and visually diminishes them dependent on the deviation of the target product’s composition from dietary recommendations. In a study with 12 participants, we found that ShoppingCoach increased compliance with dietary recommendations from 75% to 100% and reduced decision time by 41%. These results demonstrate the promising potential of DR in promoting healthier food choices and thus enhancing public health.

Text Reference

Jannis Strecker, Jing Wu, Kenan Bektaş, Conrad Vaslin, and Simon Mayer. 2024. ShoppingCoach: Using Diminished Reality to Prevent Unhealthy Food Choices in an Offline Supermarket Scenario. In Extended Abstracts of the CHI Conference on Human Factors in Computing Systems (CHI EA ’24), May 11–16, 2024, Honolulu, HI, USA. ACM, New York, NY, USA, 8 pages. https://doi.org/10.1145/3613905.3650795

BibTex Reference
@inproceedings{10.1145/3613905.3650795,
author = {Strecker, Jannis and Wu, Jing and Bekta\c{s}, Kenan and Vaslin, Conrad and Mayer, Simon},
title = {ShoppingCoach: Using Diminished Reality to Prevent Unhealthy Food Choices in an Offline Supermarket Scenario},
year = {2024},
isbn = {9798400703317},
publisher = {Association for Computing Machinery},
address = {New York, NY, USA},
url = {https://doi.org/10.1145/3613905.3650795},
doi = {10.1145/3613905.3650795},
abstract = {Non-communicable diseases, such as obesity and diabetes, have a significant global impact on health outcomes. While governments worldwide focus on promoting healthy eating, individuals still struggle to follow dietary recommendations. Augmented Reality (AR) might be a useful tool to emphasize specific food products at the point of purchase. However, AR may also add visual clutter to an already complex supermarket environment. Instead, reducing the visual prevalence of unhealthy food products through Diminished Reality (DR) could be a viable alternative: We present ShoppingCoach, a DR prototype that identifies supermarket food products and visually diminishes them dependent on the deviation of the target product’s composition from dietary recommendations. In a study with 12 participants, we found that ShoppingCoach increased compliance with dietary recommendations from 75\% to 100\% and reduced decision time by 41\%. These results demonstrate the promising potential of DR in promoting healthier food choices and thus enhancing public health.},
booktitle = {Extended Abstracts of the 2024 CHI Conference on Human Factors in Computing Systems},
articleno = {288},
numpages = {8},
keywords = {diminished reality, extended reality, food choices, health informatics, nutrition and health},
location = {Honolulu, HI, USA},
series = {CHI EA '24}
}

Teaser Video

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QR Code Integrity by Design

In

Extended Abstracts of the CHI Conference on Human Factors in Computing Systems (CHI EA ’24)

Date

May 11, 2024

Authors

Luka Bekavac, Simon Mayer, and Jannis Strecker

Abstract

As QR codes become ubiquitous in various applications and places, their susceptibility to tampering, known as quishing, poses a significant threat to user security. In this paper we introduce SafeQR codes that address this challenge by introducing innovative design strategies to enhance QR code security. Leveraging visual elements and secure design principles, the project aims to make tampering more noticeable, thereby empowering users to recognize and avoid potential phishing threats. Further, we highlight the limitations of current user-education methods in combating quishing and propose different attacker models tailored to address quishing attacks. In addition, we introduce a multi-faceted defense strategy that merges design innovation with user vigilance. Through a user study, we demonstrate the efficacy of ’Integrity by Design’ QR codes. These innovatively designed QR codes significantly raise user suspicion in case of tampering and effectively reduce the likelihood of successful quishing attacks.

Text Reference

Luka Bekavac, Simon Mayer, and Jannis Strecker. 2024. QR Code Integrity by Design. In Extended Abstracts of the CHI Conference on Human Factors in Computing Systems (CHI EA ’24), May 11–16, 2024, Honolulu, HI, USA. ACM, New York, NY, USA, 9 pages. https://doi.org/10.1145/3613905.3651006

BibTex Reference
@inproceedings{10.1145/3613905.3651006,
author = {Bekavac, Luka Jure Lars and Mayer, Simon and Strecker, Jannis},
title = {QR-Code Integrity by Design},
year = {2024},
isbn = {9798400703317},
publisher = {Association for Computing Machinery},
address = {New York, NY, USA},
url = {https://doi.org/10.1145/3613905.3651006},
doi = {10.1145/3613905.3651006},
abstract = {As QR codes become ubiquitous in various applications and places, their susceptibility to tampering, known as quishing, poses a significant threat to user security. In this paper we introduce SafeQR codes that address this challenge by introducing innovative design strategies to enhance QR code security. Leveraging visual elements and secure design principles, the project aims to make tampering more noticeable, thereby empowering users to recognize and avoid potential phishing threats. Further, we highlight the limitations of current user-education methods in combating quishing and propose different attacker models tailored to address quishing attacks. In addition, we introduce a multi-faceted defense strategy that merges design innovation with user vigilance. Through a user study, we demonstrate the efficacy of ’Integrity by Design’ QR codes. These innovatively designed QR codes significantly raise user suspicion in case of tampering and effectively reduce the likelihood of successful quishing attacks.},
booktitle = {Extended Abstracts of the 2024 CHI Conference on Human Factors in Computing Systems},
articleno = {274},
numpages = {9},
keywords = {QR code based phishing, QR codes, phishing susceptibility, privacy, quishing},
location = {Honolulu,HI,USA},
series = {CHI EA '24}
}
}

Teaser Video

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