Brian C. Ladd

Computer games in the classroom, or, how to get perfect attendance, even at 8 AM

In this special session, we will compare and contrast several game engines that have been used in game development courses, and describe our experiences teaching such courses.

Enhanced graph models in the Web: multi-client, multi-head, multi-tail browsing

One key to the wide and rapid acceptance of the World Wide Web is the simplicity of its model. We see this in its short-lived connections and generally stateless servers, as well as in the relationship between nodes (HTML pages) and embedded links. Though these factors contribute to the Webs success, they also come at a cost: precise control of how documents are presented to the user is beyond this basic model. Richer graph models permit authors to “program” the browsing behavior they want readers to see by turning the hypertext into a hyperprogram with specific semantics. Multiple browsing streams can be started under the authors control and then kept in step through the synchronization mechanisms provided by the graph model. Our current work adds a Semantic Web Graph Layer (SWGL) which allows dynamic interpretation of link and node structures according to graph models. As a motivating example of the utility of the SWGL, we have chosen to implement the graph model for Colored Petri Nets (CPNs). The previous MMM project[6] implemented a limited subset of the Petri net model to give Web authors the ability to control concurrency and synchronization in a single readers browsing session. CPNs extend this protocol to give control of multiple readers in a like fashion. This paper details the SWGL and its architecture, some sample protocol implementations, and the latest extensions to MHTML[6] that were necessary to support these enhancements.

The World Wide Web: what cost simplicity?

The ubiquity of the World Wide Web owes much to the simplicity of its graph model. Unfortunately that graph model omits powerful features found in traditional hypertext systems: concurrency and synchronization. These shortcomings are addressed in an extensible manner as part of the Multi-head, Multi-head, Multi-client Browsing Project; our research is focused on extending the Web Web through the use of the more powerful link semantics.