On a daily basis humans interact with an increasing variety of personal electronic devices, ranging from laptops, tablets, smartphones, and e-readers to shared devices such as projected displays and interactive, digital tabletops. An emerging area of study focuses on understanding how these devices can be used together to support collaborative work. Where prior research has shown benefits of devices used individually, there is currently a lack of understanding of how devices should be used in conjunction to optimize a group's performance. In particular, the research presented in this dissertation combines qualitative and quantitative analyses of group work in three empirical studies to link the use of shared and personal devices to changes in group performance and process. In the first study, participants performed an optimization task with either a single, shared projected display or with the shared, projected display and personal laptops. Analyses of study data indicated that when personal displays were present, group performance was improved for the optimization task ($p = 0.025$). However, personal devices also reduced a group's ability to coordinate ($p = 0.016$). Additionally, when personal devices were present, individuals primarily used those devices instead of dividing time between their laptops and the shared display. To further investigate the support that shared displays provide groups, and in particular, how shared displays might support group work in multi-display settings, a follow-up study was conducted. The second study investigated how two different types of shared displays supported group work. In particular, shared workspaces, which allowed multiple users to simultaneously interact with shared content, and status displays, which provided awareness of the overall problem state to groups, were investigated. While no significant impact on group performance was observed between the two shared display types, qualitative analysis of groups working in these conditions provided insight into how the displays supported collaborative activities. Shared workspace displays provided a visual reference that aided individuals in grounding communication with their collaborators. On the other hand, status displays enabled the monitoring of a group's overall task progress. Regardless of which display was present, an individual's gaze and body position relative to the shared display supported the synchronization of group activities. Finally, where the previous two studies identified collaborative activities that were supported by the use of shared and personal displays, the experimental task performed by participants did not explore the transfer of task materials between shared and personal devices or alternative personal and shared devices. The third study addressed these limitations through the adoption of a new experimental task that enabled the exploration of how the manipulation of task artefacts supported collaborative activities, and alternative shared and personal devices in the form of interactive digital tabletops and tablet computers. In particular, the third study compared how personal and shared displays supported sensemaking groups working under three conditions: with shared, digital tables, with shared digital tables plus personal tablets, and with only personal tablets. Quantitative analyses revealed that the presence of the shared, digital tabletop significantly improved a group's ability to perform the sensemaking task ($p = 0.019$). Further, qualitative analyses revealed that the table supported key sensemaking activities: the prioritization of task materials, the ability to compare data, and the formation of group hypotheses. This dissertation makes four primary contributions to the field of Computer Supported Cooperative Work. First, it identifies cases where the presence of shared and personal displays provide performance benefits to groups, and through qualitative analyses links these performance benefits to group processes. Second, observed uses are grounded in an established process model, and used to identify collaborative activities that are supported by personal and shared devices. Third, equity of participation on shared displays is found to positively correlate ($p = 0.028$), and equity of participation on personal displays is found to negatively correlate ($p = 0.01$) with group performance for sensemaking tasks. Fourth, the method for studying group process and performance based on teamwork and taskwork provides a useful foundation for future studies of collaborative work.

This dissertation proposes principles for the design of ubiquitous health monitoring applications that support reflection and learning in context of diabetes management. Due to the high individual differences between diabetes cases, each affected individual must find the optimal combination of lifestyle alterations and medication through reflective analysis of personal diseases history. This dissertation advocates using technology to enable individuals' proactive engagement in monitoring of their health. In particular, it proposes promoting individuals' engagement in reflection by exploiting breakdowns in individuals' routines or understanding; supporting continuity in thinking that leads to a systematic refinement of ideas; and supporting articulation of thoughts and understanding that helps to transform insights into knowledge. The empirical evidence for these principles was gathered thought the deployment studies of three ubiquitous computing applications that help individuals with diabetes in management of their diseases. These deployment studies demonstrated that technology for reflection helps individuals achieve their personal disease management goals, such as diet goals. In addition, they showed that using technology helps individuals embrace a proactive attitude towards their health indicated by their adoption of the internal locus of control.

El uso creciente de dispositivos móviles, infraestructuras inalámbricas e Internet está cambiando nuestra vida diaria, no solo la manera en que nos comunicamos o compartimos información, sino también cómo nos relacionamos con el entorno. A través de nuestras interacciones con estas tecnologías, accedemos y generamos una membrana de información que se cierne sobre los espacios donde vivimos y que visitamos. Sin embargo, esta capa de información solo modela de manera imperfecta la realidad debido a una digitalización tosca y a limitaciones tecnológicas, que hacen peligrar la interacción humana. Por otro lado, la presencia de esta información geográfica ubicua generada por los usuarios abre nuevas perspectivas para la comprensión de las actividades humanas en el espacio y el tiempo. Esta tesis acepta el reto de investigar estos aspectos de las interacciones humanas con la información geográfica ubicua. Con un enfoque cualitativo y cuantitativo, discernimos las implicaciones de la integración de información geográfica ubicua y las resultantes estrategias de los usuarios para hacer frente a la incertidumbre espacial. Entonces, explotamos esta contribución para analizar enfoques novedosos con el objetivo de inferir actividades espacio-temporales de individuos y grupos respetando su privacidad. Demostramos la aplicabilidad de nuestras soluciones en los ámbitos de la investigación de mercados y el urbanismo. / The increasing use of mobile devices, wireless infrastructures, and the Internet is changing our daily lives, not only in the way we communicate with each other or share information but also how we relate to the environment. Through our interactions with these technologies we access and generate an informational membrane, hovering over the spaces we live in and visit. However, this information layer only imperfectly models the reality due to coarse digitization and technological limitations, challenging the human interaction. On the other hand, the presence of this user-generated ubiquitous geographic information opens novel perspectives in understanding human activities over space and time. This thesis takes on the challenge of exploring these aspects of human interactions with ubiquitous geographic information. Through qualitative lenses, we discern the implications of the integration of ubiquitous geographic information and the resulting users strategies to cope with spatial uncertainty. Then, we exploit this contribution to explore novel approaches to infer individuals and groups time-space activities with respect to their privacy. We demonstrate the applicability of our solutions in the domains of market research and urbanism.

Zugl.: Saarbrücken, Univ., Diss., 2006

Thesis (Ph.D.)--Computing, Georgia Institute of Technology, 2009. / Committee Chair: Aaron Bobick; Committee Member: Charles Isbell; Committee Member: David Hogg; Committee Member: Irfan Essa; Committee Member: James Rehg

Thesis (Ph.D)--Computing, Georgia Institute of Technology, 2009. / Committee Chair: Stasko, John T.; Committee Member: Edwards, Keith; Committee Member: Greenberg, Saul; Committee Member: Grinter, Beki; Committee Member: Guzdial, Mark. Part of the SMARTech Electronic Thesis and Dissertation Collection.

Thesis (Ph. D.)--Universität des Saarlands, 2005. / Includes bibliographical references (p. 253-268) and index.

Techn. Universiẗat, Diss., 2003--Darmstadt. / Dateien in unterschiedlichen Formaten.-Enth.: Textteil. CD-Daten.

Techn. Hochsch., Diss., 2005--Aachen.

Thesis (doctoral) - Univ., Saarbrücken, 2006. / Includes bibliographical references and index.