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Browsing by Author "Esakia, Andrey"

Now showing 1 - 4 of 4
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    Development and Exploratory Findings of a Smartwatch Interface to Facilitate Group Cohesion in a Statewide Health Promotion Program
    Esakia, Andrey (Virginia Tech, 2017-05-25)
    Background: Physical inactivity of the general population is a major public health concern in the US and around the world. Community-based interventions that include evidence-based principles of group dynamics are effective at improving individual-level physical activity behaviors as well as changing social norms for health behaviors. The use of technologies such as smartwatches has a potential to channel and amplify underlying group dynamics principles in such interventions. In order to explore the use of smartwatches for group dynamics-based physical activity interventions, a smartwatch centered system was designed and deployed as part of an eight-week pilot study. Objectives: The primary goal of this study was to explore the degree to which smartwatches effectively channel group dynamics strategies in the context of an eight-week community based physical activity intervention. Methods: In this explanatory mixed-methods study, system usage data were analyzed (e.g., frequency of interaction with smartwatch and smartphone) and participant physical activity (e.g., participant steps tracked by the system). To provide a richer picture of the user experience, use of features, and impact of group dynamics, participants were invited to participate in one-on-one interviews after the pilot program. The group dynamics-based questions centered on the individual’s attraction to the group task and socially as well as the individual’s perception of group integration around the task and as a social unit (i.e., the four dimensions of cohesion). The interview recordings were transcribed verbatim and analyzed via an abbreviated grounded theory approach. The system usage data was visually and numerically summarized. Results: Five of the seven participants completed interviews. The interview analysis resulted in 365 meaning units representing 2 themes (related to user experience with devices and manifestations of group dynamic principles), 4 sub-themes and 23 categories. The participants completed 31.3 (SD=2.91) miles per week and engaged with the smartwatch and the Android app 2.6 and 1.5 times a day, respectively. Analysis of interviews and the system usage logs from five participants, reveal sustained engagement with the smartwatch and the smartphone app. The system facilitated self-reflection and awareness in terms of physical activity levels, encouraged interactions with the team members and helped them to stay aware of the daily goals. Additionally, the participants reported habit formation in terms of wearing and using the smartwatch on the daily basis. Implications: This study provides preliminary support that accessible information via the custom smartwatch watchface can be a viable solution for retaining higher participant engagement during group dynamics-based community interventions. Such devices can help expand group-dynamics interventions by making them less depended on in-person delivery methods.
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    Experiments on the Random Packing of Tetrahedral Dice
    Jaoshvili, A.; Esakia, Andrey; Porrati, M.; Chaikin, P. M. (American Physical Society, 2010-05-07)
    Tetrahedra may be the ultimate frustrating, disordered glass forming units. Our experiments on tetrahedral dice indicate the densest (volume fraction phi = 0.76 +/- .02, compared with phi(sphere) = 0.64), most disordered, experimental, random packing of any set of congruent convex objects to date. Analysis of MRI scans yield translational and orientational correlation functions which decay as soon as particles do not touch, much more rapidly than the similar to 6 diameters for sphere correlations to decay. Although there are only 6.3 +/- .5 touching neighbors on average, face-face and edge-face contacts provide enough additional constraints, 12 +/- 1.6 total, to roughly bring the structure to the isostatic limit for frictionless particles. Randomly jammed tetrahedra form a dense rigid highly uncorrelated material.
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    Large Display Interaction via Multiple Acceleration Curves and Multifinger Pointer Control
    Esakia, Andrey; Endert, Alex; North, Christopher L. (Hindawi, 2014-11-25)
    Large high-resolution displays combine high pixel density with ample physical dimensions. The combination of these factors creates a multiscale workspace where interactive targeting of on-screen objects requires both high speed for distant targets and high accuracy for small targets. Modern operating systems support implicit dynamic control-display gain adjustment (i.e., a pointer acceleration curve) that helps to maintain both speed and accuracy. However, large high-resolution displays require a broader range of control-display gains than a single acceleration curve can usably enable. Some interaction techniques attempt to solve the problem by utilizing multiple explicit modes of interaction, where different modes provide different levels of pointer precision. Here, we investigate the alternative hypothesis of using a single mode of interaction for continuous pointing that enables both (1) standard implicit granularity control via an acceleration curve and (2) explicit switching between multiple acceleration curves in an efficient and dynamic way. We evaluate a sample solution that augments standard touchpad accelerated pointer manipulation with multitouch capability, where the choice of acceleration curve dynamically changes depending on the number of fingers in contact with the touchpad. Specifically, users can dynamically switch among three different acceleration curves by using one, two, or three fingers on the touchpad.
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    Large display interaction via multiple acceleration curves on a touchpad
    Esakia, Andrey (Virginia Tech, 2013-12-09)
    Large, high resolution displays combine high pixel density with ample physical dimensions. Combination of these two factors creates a multi-scale workspace where object targeting requires both high speed and high accuracy for nearby and far apart targeting. Modern operating systems support dynamic control-display gain adjustment (i.e. cursor acceleration) that helps to maintain both speed and accuracy. However, very large high resolution displays require broad range of control-display gain ratios. Current interaction techniques attempt to solve the problem by utilizing multiple modes of interaction, where different modes provide different levels of pointer precision. We are investigating the question of the value of allowing users to dynamically choose granularity levels for continuous pointing within single mode of interaction via multiple acceleration curves. Our solution offers different cursor acceleration curves depending on the targeting conditions, thus broadening the range of control-display ratios. Our approach utilizes a consumer multitouch touchpad that allows fast and accurate detection of multiple fingers. A user can choose three different acceleration curves based on how many fingers are used for cursor positioning. Our goal is to investigate the effects of such multi-scale interaction and to compare it against standard single curve interaction.