Bo Yu’s research while affiliated with Pennsylvania State University and other places

Maintaining awareness is central to effective coordination and collaboration in complex human activities, but pervasive computing environment has not adequately addressed this requirement from a formal design perspective. Existing awareness solutions work only for relatively small-scale collaboration in traditional workplace, and they suffer from either inflexibility or lack of scalability if applied to pervasive computing environment. Based on our analysis of awareness life cycle, we propose a model of event-based awareness promotion mechanism. Our model extends focus-nimbus model and reaction-diffusion model with computational reasoning of dependencies and diffusion paths. The model is partially validated through implementation of our experimental environment, DACE (Dependency-based Awareness and Coordination Environment), which supports belief tracking, updates, and reasoning tasks and enhance the cognitive capability in awareness interpretation and use. Key principles of the DACE system are explained through a hypothetical scenario of search and rescue exercise typical in emergency response applications.

One of the fundamental issues of geographical information science is to design GIS interfaces and functionalities in a way that is easy to understand, teach, and use. Unfortunately, current geographical information systems (including ArcGIS) remains very difficult to use as spatial analysis tools, because they organize and expose functionalities according to GIS data structures and processing algorithms. As a result, GIS interfaces are conceptually confusing, cognitively complex, and semantically disconnected from the way human reason about spatial analytical activities. In this article, we propose an approach that structures GIS analytical functions based on the notion of “analytical intent”. We describe an experiment that replaces ArcGIS desktop interface with a conversational interface, to enable mixed-initiative user-system interactions at the level of analytical intentions. We initially focus on the subset of GIS functions that are relevant to “finding what's inside” as described by Mitchell, but the general principles apply to other types of spatial analysis. This work demonstrates the feasibility of delegating some spatial thinking tasks to computational agents, and also raises future research questions that are key to building a better theory of spatial thinking with GIS.

Mobile applications are increasingly taking advantages of the diverse geospatial web services to meet the information needs of their users. However, matching available web services to user's information needs is not a trivial task, as there are many contextual factors that may influence the fitness of use. In addition, mobile activities can be highly dynamic and interleaving, which demand certain level of context-adaption for web service matching policies. Previous work on context-based service matching and composition tends to focus on environmental and functional contexts that can be either sensed directly or defined a prior, and they assume relatively stable user activities. In this paper, we describe a method for representing and reasoning the intentional structures of mobile activities and use it to contextualize mobile map services. Our context model treats a user's mobile activity as an evolving collaborative plan situated in a set of physical and mental factors. The model explicitly reasons on the intentional structure of the mobile activity to determine the appropriate service matching policy on the fly. The feasibility and benefit of using this model is demonstrated through the implementation of a prototype system, MyTour - a mobile city tour guide application.

GIS has been widely used for supporting decision-making in local communities. However, limited studies have been conducted to use maps directly as a communication tool to support community discussion. In this paper, we explore the potential of using geospatial annotations to facilitate map-based online discussion in local communities. We developed a prototype system, which explicitly links participants' discussion contributions with geographic references. The system is based on conceptual understanding of map-based discussion space, which guides the generation of system requirements. We demonstrate the utility of such systems by a hypothetical scenario of building a Smoke-Free campus in a university community.

Many public policies and decisions deal with geospatially expressed problems that are complex and controversial in nature. Broad participation of all interested parties in the form of deliberative dialogues is crucial to making trustworthy decisions. However, supporting deliberative dialogues on spatial problems places unique requirements for technology mediation that go beyond the current state of research on public participation geographical information systems (PPGIS) and related tech-nologies. In this article, we analyze the challenges of facilitating effective deliberation processes and highlight the progress needed to support spatially-enabled public deliberation technologies. Then, we present our GeoDeliberative Annotation Tech-nology (GeoDAT) as a framework for addressing the above challenges. GeoDAT uses spatial annotation objects as models for deliberative artifacts, and manages annotations by a spatial data model that reflects the ecological relationships among annotations, visual contexts, discussion threads, spatial referents, and the cognitive states of their holders. As a proof of the concept, we have implemented GeoDelib-erator based on the GeoDAT framework. GeoDeliberator is based on Web 2.0 technology and implemented in AJAX technology, and it offers some unique spatial annotation capture, retrieval and visualization capabilities, such as context memory, reference to multiple geo-objects in one annotation, inferring and visualizing new relations using spatial-temporal and thread-based reasoning, and user-controlled annotation sharing. We demonstrate the utility of GeoDeliberator through a simulated scenario where a community in a university campus deliberates on the alternative courses of actions available for building a smoke-free campus.

Geographically oriented search must consider both the thematic and geographic dimensions of relevance when matching documents to queries. We propose a dynamic document ranking scheme to combine the thematic and geographic relevance measures on a per-query basis. Query specificity is introduced to determine the relative weights of different sources of ranking evidence for each query. A preliminary evaluation comparing with human judgment shows that our method to distinguish different types of geo-referenced queries based on query specificity is promising to address the issue of relevance combination in GIR document ranking. In addition, we explore the possibility of using Dempster-Shafer's theory to combine the two different sources of ranking evidence.

Emergency response involves collaboration among search and rescue workers, medical staff, transportation coordinators, and others to save human lives and minimize damages. While carrying out local activities, members of the teams must also attend to new events happening elsewhere that may affect their work, and be prepared to adjust their activities accordingly. This paper describes a computer supported coordination system, DACE (Dependency-based Awareness and Coordination Environment), which offers a scalable solution to coordination in emergency response. The system serves as a cognitive aid to human actors in both maintaining a group mental model of the overall collaborative activities and their dependencies, and determining the effects of events as they propagate through the web of dependencies. We demonstrate the principles and utility of the DACE system through a hypothetical scenario of search and rescue exercise. This work contributes to the goal of scaling up awareness-based coordination in emergency response.