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Auflistung nach Autor:in "Schaffer, Stefan"

1 - 8 von 8
  • Workshopbeitrag
    An analysis of the effects of swarm cycling on cyclists’ stress levels
    (Mensch und Computer 2023 - Workshopband, 2023) Schaffer, Stefan; Meng, Linglong; Hemdane, Alaaeddine; Wolf, Katrin; Tsovaltzi, Dimitra; Chehayeb, Lara; Gebhard, Patrick
    Swarm cycling has been proposed in previous researches as a novel concept for urban mobility, by adopting the "safety in number" approach, to enhance the visibility of cyclists in urban traffic and to increase the safety of cyclists. To investigate the effects of swarm cycling on the stress level of bicyclists, we conducted an experiment in an enclosed traffic training field with stressors, such as construction sites, etc. to simulate the stress situations in real traffic. A stress detection system utilizing the Galvanic Skin Response (GSR) sensor and an Android application was developed to monitor participants’ stress responses during cycling. In this research, 21 participants engaged in various cycling scenarios, including cycling alone, cycling within a swarm, and cycling in different positions within the swarm. GSR signal data were collected to quantify the number of stress peaks experienced by each participant during the rides. The data were subjected to statistical analysis to compare stress levels among the different cycling scenarios. The results of the statistical analysis indicate that swarm cycling has a positive impact on individual cyclist stress levels compared to cycling alone. However, there was no statistically significant difference in stress levels observed among different cycling positions within the swarm. This research provides insights into the potential benefits of swarm cycling as an urban mobility solution, emphasizing its positive influence on cyclist stress levels, thus encouraging the adoption of this novel concept to enhance safety and comfort for urban cyclists.
  • Konferenzbeitrag
    Benutzerstudien zur Bewertung multimodaler, interaktiver Anzeigetafeln in unterschiedlichen Entwicklungsstufen
    (Workshop-Proceedings der Tagung Mensch & Computer 2009, 2009) Schaffer, Stefan; Seebode, Julia; Wechsung, Ina; Metze, Florian; Möller, Sebastian
    Gegenstand des Beitrages sind zwei Evaluationsstudien einer interaktiven, digitalen Anzeigetafel. Das ursprünglich unimodale, Touchscreen-basierte System wurde schrittweise erweitert. Dabei wurde zunächst eine Sprachsteuerung implementiert, in einer zweiten Entwicklungsstufe wurde anschließend eine Gesichtserkennung ergänzt. Nach jeder Systemmodifikation erfolgte eine Benutzerstudie zur Bewertung der vom Nutzer wahrgenommenen Qualität der Interaktion mittels subjektiver, direkter Fragebogendaten und technischer, indirekter Performanzdaten. Die Ergebnisse der Fragebogendaten zeigen, dass die multimodalen Systemvarianten hinsichtlich der hedonischen Qualitäten besser beurteilt wurden als die unimodale Variante. Dies war auch dann zu beobachten, wenn sich die Bewertungen bezüglich der Usability nicht erhöhten. Die Analyse der indirekten Daten zeigte eine Verbesserung der Usability, die sich jedoch nicht in den Nutzerurteilen widerspiegelte.
  • Konferenzbeitrag
    “HalloBzar”: A German chatbot for accessing the regional digital marketplace
    (INFORMATIK 2023 - Designing Futures: Zukünfte gestalten, 2023) Bawa, Vanishika; Baroud, Ibrahim; Schaffer, Stefan
    As part of the “Stadt-Land-Fluss” project, we investigate the usage of an AI-powered chatbot to support three key players of the regional food supply chain: producers, food processors, and buyers, in selling or buying their products digitally. A Minimal Viable Prototype was developed with input from domain specialists and includes two scenarios with concrete use cases; namely, “see crop plannings”, “create sales item”, “looking for a food-processor” in the first and, “create delivery series” or “see offers” in the second. Additionally, the chatbot provides personalized follow-up questions in the case where an offer or crop planning is due. We identify 17 intents and 9 entities and evaluate the performance of NLU components using 5-fold cross validation. This work contributes to the field by curating domain-specific use cases and data based on expert insights. We also extend the data using large language models. Additionally, we show that using DIET with spaCy outperforms using DIET with BERT-based tokenizers and featurizers in Intent Detection (ID) and Entity Recognition (ER) on our data when keeping other parts of the chatbot constant.
  • Workshopbeitrag
    Intermodal personalized Travel Assistance and Routing Interface
    (Mensch & Computer 2014 - Tagungsband, 2014) Schaffer, Stefan; Reithinger, Norbert
    An increasing amount of available data sources and intermodal travelling pose a challenge for the design of mobility apps. This paper examines the concept of an interface for intermodal personalized travel assistance and routing. The analysis of two central use cases intermodal routing and personalization revealed pitfalls and gaps for the design of mobility apps.
  • Workshopbeitrag
    Optimization of Swarm Formation in Swarm Cycling
    (Mensch und Computer 2023 - Workshopband, 2023) Meng, Linglong; Parwal, Krutarth; Schaffer, Stefan
    Cycling in groups improves safety by adopting the "safety in numbers" approach, reducing the risk of collisions with other traffic units, and enhancing the visibility of cyclists on the road, with cyclists riding as a more prominent and visible unit. Swarm cycling, a novel urban mobility concept, involves cyclists riding together in a group in a common direction or destination. The swarms are formed automatically via peer-to-peer connection when cyclists come in proximity, and the information of the swarm and individual cyclists will be synchronized within the swarm via a Nearby Mesh Network. In order to improve the existing swarm application, a pre-test with HCI experts was conducted in a low-traffic and enclosed area. The results of the pre-test round revealed that swarm formation could be optimized by adding more real-time information about the swarm to the user. Two distinct processes based on the user state (static, and dynamic) are developed for the optimization of the swarm formation, and integrated into the swarm cycling system to provide cyclists with information such as the reachability of the swarm, estimated arrival time, distance, and recommended speed to help the cyclist to approach the swarm. Online reviews from the same HCI experts confirmed the positive effect of realtime information in bridging the user’s awareness gap regarding whether the swarm is reachable and facilitating seamless swarm joining.
  • Workshopbeitrag
    Piloting vibration induction for synchrony in urban cycling
    (Mensch und Computer 2023 - Workshopband, 2023) Dauer, Louisa; Chehayeb, Lara; Ameli, Mina; Anglet, Manuel; Bhuvaneshwara, Chirag; Schaffer, Stefan; Zahn, Esther; Tsovaltzi, Dimitra
    To reduce stress in traffic situations, we investigate a possible strategy to support bike swarms by inducing interpersonal synchrony, currently a very popular construct. Synchrony may coordinate movements, reduce stress, and increase the feeling of safety during cycling in a group. Synchrony is a promising construct, but its induction in multisensory situations has not been tested. To induce synchrony in multisensory situations like the street traffic, we use tactile feedback in the form of vibrations, the influence of which has not yet been researched. To this end, we simulated a real traffic scenario in the laboratory. We explored to what extent nonintrusive vibrations can be distinctly perceived when competing with audiovisual input from street traffic, without constituting a distractor from street traffic. In the long term we want to explore possibilities of measuring and inducing synchronous leg movements in bike swarms on demand. This involves detecting the need for synchrony, for instance due to stress and lack of synchrony and prompt cyclists to follow vibration rhythms, in order to induce perceived emotional synchrony with the other group members. We present our conceptual work and technological development towards inducing synchrony through social wearables, and results from a first pilot study.
  • Workshopbeitrag
    Usability-Evaluation multimodaler Schnittstellen: Ist das Ganze die Summe seiner Teile?
    (Mensch & Computer 2009: Grenzenlos frei!?, 2009) Wechsung, Ina; Engelbrecht, Klaus-Peter; Schaffer, Stefan; Seebode, Julia; Metze, Florian; Möller, Sebastian
    Multimodale Systeme stellen dem Nutzer mehrere Kommunikationskanäle zur Verfügung. Bei der Evaluation müssen daher sowohl die einzelnen Modalitäten als auch deren Kombination in Betracht gezogen werden. Dieser Beitrag untersucht, ob, und wenn ja, wie Bewertungen für einzelne Modalitäten mit der Bewertung des Gesamtsystems zusammenhängen. Dazu wurde ein Raummanagement- und Informationssystem in zwei unimodalen und einer multimodalen Version getestet. Multiple lineare Regressionen zeigten, dass hinsichtlich Gesamt- und Globalurteilen die Bewertungen einzelner Modalitäten sehr gute Prädiktoren für die Bewertungen des Gesamtsystems sind. Für einzelne Usability-Faktoren waren die Vorhersagen allerdings weniger genau.
  • Workshopbeitrag
    Workshop on Smart Urban Micromobility
    (Mensch und Computer 2023 - Workshopband, 2023) Schneeberger, Tanja; Schaffer, Stefan; Dimitra, Tsovaltzi; Lara, Chehayeb; Patrick, Gebhard
    Urban mobility is evolving towards sustainable transportation as awareness of the environmental impact of transportation increases. In addition, efforts to improve public health, are leading to a greater focus on micromobile means of urban transport, such as bicycles or scooters. Although the number of people using micromobile urban transport is increasing, technologies to improve rider safety have been researched mainly in the context of motorized vehicles. In this workshop, we will present research and discuss ideas for smart urban micromobility. Therefore, we invite scientists and practitioners from different backgrounds to contribute with their latest work. Our goal is to bring together micromobility and technology enthusiasts to discuss and identify opportunities to provide a smart and safer mode of transportation.