Taiwoo Park

BeUpright: Posture Correction Using Relational Norm Intervention

Research shows the critical role of social relationships in behavior change, and the advancement of mobile technologies brings new opportunities of using online social support for persuasive applications. In this paper, we propose Relational Norm Intervention (RNI) model for behavior change, which involves two individuals as a target user and a helper respectively. RNI model uses Negative Reinforcement and Other-Regarding Preferences as motivating factors for behavior change. The model features the passive participation of a helper who will undergo artificially generated discomforts (e.g., limited access to a mobile device) when a target user performs against a target behavior. Based on in-depth discussions from a two-phase design workshop, we designed and implemented BeUpright, a mobile application employing RNI model to correct sitting posture of a target user. Also, we conducted a two-week study to evaluate the effectiveness and user experience of BeUpright. The study showed that the RNI model has a potential to increase efficacy, in terms of behavior change, compared to conventional notification approaches. The most influential factor of RNI model in the changing the behavior of target users was the intention to avoid discomforting their helpers. RNI model also showed a potential to help unmotivated individuals in behavior change. We discuss the mechanism of the RNI model in relation to prior literature on behavior change and implications of exploiting discomfort in mobile behavior change services.

AirSense: an intelligent home-based sensing system for indoor air quality analytics

In the U.S., people spend approximately 90 percent of their time indoors. Unfortunately, indoor air quality (IAQ) may be two to five times worse than the air outdoors, and is often overlooked. Existing IAQ monitoring technologies focus on IAQ measurements and visualization. However, the lack of information about the pollution sources as well as the seriousness of the pollution makes people feel powerless and frustrated, resulting in the ignorance of the polluted air at their homes. In this work, we fill this critical gap by presenting AirSense, an intelligent home-based IAQ sensing system that is able to automatically detect pollution events, identify pollution sources, estimate personal exposure to indoor air pollution, and provide actionable suggestions to help people improve IAQ. We have deployed AirSense at five homes to evaluate its performance and investigate how users interact with it. We demonstrate that AirSense can accurately detect pollution events, identify pollution sources, and forecast IAQ information within five minutes in both controlled and real-world settings. We further show the great potential of AirSense in increasing users awareness of IAQ and helping them better manage IAQ at their homes.

The Psychological Effects of Playing Exergames: A Systematic Review

Successful exergames should lead players not only to achieve enough level of energy expenditure but also to engage in the play itself. The aim of this study is to review studies that explored the psychological effects of playing exergames, from the viewpoint of player engagement. Peer-reviewed journal articles in English collected via database search (Science Direct, Web of Science, ACM Digital Library) from 2011 to 2015 were considered, and 45 experimental studies were selected out of 911 studies. The results show that a variety of psychological effects of engagement including enjoyment, immersion, and flow were measured in the exergame studies. In addition, physiological variables (e.g., energy expenditure), feedback modality (e.g., auditory and tactile), and play modes (e.g., solitary or group play mode) are related to psychological effects of playing exergames. Finally, salient methodological issues (e.g., validated measurement, sample size calculation) in the studies are identified and discussed.

Jasper: Sensing Gamers' Emotions Using Physiological Sensors

This paper aims to develop a system that evaluates the emotional experience of gamers based on physiological changes. A within-subject experiment with 22 participants has been designed to investigate the effects of difficulty level and social playing mode on player emotions and to examine the correlation between each emotion and the physiological changes. We demonstrate the feasibility of using commodity wearable physiological sensing devices to recognize mobile gamers emotion. Specifically, our system performs 3-level excitement classification at an accuracy of 77.38% and binary classification of happiness state at an accuracy of 73.21%. These classification results show the potential of using commodity wearable sensing devices as a valuable evaluation tool for game designers to gauge user emotions and develop personalized gaming experience.

An Exploratory Study on the Köhler Effect and Flow in Long-term Exergaming

Background. One way to motivate people to exercise is to create a motivating social context, such as group exercise, due to social comparison opportunities. However, typical group exercise is not always easy for those who have problems in scheduling or social physique anxiety. Software-generated partners (SGPs) could offer a solution because they have advantages over human partners. Aim. This exploratory study examined the psychological state of flow under Köhler paradigm over a 24-week exergame with different types of SGPs: Individual Control (IC), Always Superior Partner (AWS), and Not Always Superior Partner (NAS). Method. The experiment was a 3 (Type of the partner) × 3 (Time blocks) factorial design. Fifteen participants engaged in the experiment. A multivariate multiple regression with type of SGPs predicting flow state at the second and third block was conducted. Results. Participants with an NAS partner had significantly higher flow state, as compared to participants under IC, at both blocks. Participants with an AWS partner had approximately equal flow state, as compared to participants under IC, at both blocks. Conclusions. Possible reasons for flow perceptions with different types of SGPs over time were discussed in terms of programming SGPs and flow theory.

WHEN MIXED REALITY MEETS INTERNET OF THINGS:: Toward the Realization of Ubiquitous Mixed Reality

From panoramic paintings and stereoscopic photos in the early 19th century, there has been a centurylong effort to realize mixed reality, interweaving real and virtual worlds that interact with each other. Recently, over the past few years, we have witnessed the first wave of affordable mixed reality platforms, such as Oculus Rift and Microsoft HoloLens hitting the market. In particular, 2017 was the showcase year of mixed reality technologies: The Academy awarded its first Oscar to virtual reality storytelling1; AAA caliber virtual reality games started to hit the market with impacts2. Furthermore, major mobile operating systems, including Android and iOS, began to support augmented reality at the platform level (e.g., Android ARCore, Apple ARKit). Looking down the road, a recent forecast by Orbis Research projects over

Exploring the potential of modifying visual stimuli in virtual reality to reduce hand tremor in micromanipulation tasks

40 billion mixed reality market worldwide by 20203.

When Virtual Reality Meets Internet of Things in the Gym: Enabling Immersive Interactive Machine Exercises

Involuntary hand tremor has been a serious challenge in micromanipulation tasks and thus draws a significant amount of attention from related fields. To minimize the effect of the hand tremor, a variety of mechanically assistive solutions have been proposed. However, approaches increasing human awareness of their own hand tremor have not been extensively studied. In this paper, a head mount display based virtual reality (VR) system to increase human self-awareness of hand tremor is proposed. It shows a user a virtual image of a handheld device with emphasized hand tremor information. Provided with this emphasized tremor information, we hypothesize that subjects will control their hand tremor more effectively. Two methods of emphasizing hand tremor information are demonstrated: (1) direct amplification of tremor and (2) magnification of virtual object, in comparison to the controlled condition without emphasized tremor information. A human-subject study with twelve trials was conducted, with four healthy participants who performed a task of holding a handheld gripper device in a specific direction. The results showed that the proposed methods achieved a reduced level of hand tremor compared with the control condition.

Factors Leading to Viral Intention on Exercise Posts

With the advent of immersive virtual reality (VR) head-mounted displays (HMD), we envision that immersive VR will revolutionize the personal fitness experience in our daily lives. Toward this vision, we present JARVIS, a virtual exercise assistant that is able to provide an immersive and interactive gym exercise experience to a user. JARVIS is enabled by the synergy between Internet of Things (IoT) and immersive VR. JARVIS employs miniature IoT sensing devices removably attachable to exercise machines to track a multitude of exercise information including exercise types, repetition counts, and progress within each repetition in real time. Based on the tracked exercise information, JARVIS shows the user the proper way of doing the exercise in the virtual exercise environment, thereby helping the user to better focus on the target muscle group. We have conducted both in-lab experiments and a pilot user study to evaluate the performance and effectiveness of JARVIS, respectively. Our in-lab experiments with fifteen participants show that JARVIS is able to segment exercise repetitions with an average accuracy of 97.96% and recognize exercise types with an average accuracy of 99.08%. Our pilot user study with ten participants shows statistically significant improvements in perceived enjoyment, competence, and usefulness with JARVIS compared to a traditional machine exercise setting (p < 0.05). Finally, our surface electromyography (sEMG) signal analysis conducted during the pilot user study shows statistically significant improvement in terms of muscle activation (p < 0.01), indicating the potential of JARVIS in providing an engaging and effective guidance for machine exercises.

Demo: Towards Immersive and Interactive Gym Exercises

Exercise report posts generated by mobile exercise apps (i.e., Nike Plus and Endomondo) have shown potential to encourage exercisers (e.g., runners) by providing them a sense of social support from others. From the perspective of support-givers, the motivational factors for engaging in such exercise-related posts are largely underexplored. Under the framework of Self-Determination Theory, this study investigates associations among need satisfaction for relatedness, autonomy, tie-strength, exercise intention and viewers’ viral behaviors for exercise posts in social media. Study findings highlight the importance of increasing viewers’ relatedness through engaging exercise posts.