Crossmodal displays : coordinated crossmodal cues for information provision in public spaces

PhD ThesisThis thesis explores the design of Crossmodal Display, a new kind of display-based interface that aims to help prevent information overload and support information presentation for multiple simultaneous people who share a physical space or situated interface but have different information needs and privacy concerns. By exploiting the human multimodal perception and utilizing the synergy of both existing public displays and personal displays, crossmodal displays avoid numerous drawbacks associated with previous approaches, including a reliance on tracking technologies, weak protection for user‟s privacy, small user capacity and high cognitive load demands. The review of the human multimodal perception in this thesis, especially multimodal integration and crossmodal interaction, has many design implications for the design of crossmodal displays and constitutes the foundation for our proposed conceptual model. Two types of crossmodal display prototype applications are developed: CROSSFLOW for indoor navigation and CROSSBOARD for information retrieval on high-density information display; both of these utilize coordinated crossmodal cues to guide multiple simultaneous users‟ attention to publicly visible information relevant to each user timely. Most of the results of single-user and multi-user lab studies on the prototype systems we developed in this research demonstrate the effectiveness and efficiency of crossmodal displays and validate several significant advantages over the previous solutions. However, the results also reveal that more detailed usability and user experience of crossmodal displays as well as the human perception of crossmodal cues should be investigated and improved. This thesis is the first exploration into the design of crossmodal displays. A set of design suggestions and a lifecycle model of crossmodal display development have been produced, and can be used by designers or other researchers who wish to develop crossmodal displays for their applications or integrate crossmodal cues in their interfaces

Contextual Factors Affecting Information Sharing Patterns in Technology Mediated Communication

In this thesis, we investigate how and what contextual factors affect user’s information sharing. We build our work on six individual research projects which cover a variety of systems (search engines, social network sites, teleconferencing systems, monitoring technology, and general purpose conversational agents) in a variety of communication scenarios with diverse relationships and dispositions of users. Alongside detailed findings for particular systems and communication scenarios from each individual project, we provide a consolidated analysis of these results across systems and scenarios, which allows us to identify patterns specific for different system types and aspects shared between systems. In particular, we show that depending on the system’s position between a user and an intended information receiving agent – whether communication happens through, around, or directly with the system – the system should have different patterns of operational adaptation to communication context. Specifically, when communication happens through the system, the system needs to gather communication context unavailable to the user and integrate it into information communication; when communication happens around the system, the system should adapt its operations to provide information in the most contextually suitable format; finally, when a user communicates with the system, the role of the system is to “match” this context in communication with the user. We then argue that despite the differences between system types in patterns of required context-based adaptation, there are contextual factors affecting user’s information sharing intent that should be acknowledged across systems. Grounded in our cumulative findings and analysis of related literature, we identify four such high-level contextual factors. We then present these four factors synthesized into an early design framework, which we call SART according to the included factors of space, addressee, reason, and time. Each factor in SART is presented as a continuum defined through a descriptive dichotomy: perceived breadth of communication space (public to private); perceived specificity of an information addressee (defined to undefined); intended reason for information sharing (instrumental to objective); and perceived time of information relevance and life-span (immediate to indefinite)