A State Transition Model for Building Rule-Based Systems.

A State Transition Model (STM) is described for building real- time, continuous-operation, transaction-processing expert systems for the maintenance of complex physical systems. An important part of expertise in the maintenance domain is the knowledge of sequence and problem-solving strategies, also called the control knowledge which expresses the overall structure of the solution. Current rule-based systems often blur the distinction between domain knowledge and control knowledge, because rules are well suited to expressing small, independent inferences, but not the overall structure of the solution. An STM enhances the transparency and expressiveness of rule-based systems by making control knowledge explicit. The traditional rule- based production system architecture has been augmented with an STM to develop a framework for building hybrid expert systems.