Semantic Web Reasoning Using a Blackboard System

In this paper, we discuss the need for a hybrid reasoning approach to handing Semantic Web (SW) data and explain why we believe that the Blackboard Architecture is particularly suitable. We describe how we have utilised it for coordinating a combination of ontological inference, rules and constraint based reasoning within a SW context. After describing the metaphor on which the Blackboard Architecture is based we introduce its key components: the blackboard Panels containing the solution space facts and problem related goals and sub-goals; the differing behaviours of the associated Knowledge Sources and how they interact with the blackboard; and, finally, the Controller and how it manages and focuses the problem solving effort. To help clarify, we use our test-bed system, the AKTive Workgroup Builder and Blackboard (AWB+B) to explain some of the issues and problems encountered when implementing a SW Blackboard System in a problem oriented context.