Simulation of Petri Nets in Rule-Based Expert System Shell McESE

There exist various tools for knowledge representation and modelling in artificial intelligence. We have designed and built a software tool called McESE (McMaster Expert System Environment) that comprises three such represen tations: pro duction systems, n eural nets, an d Petri nets. T he first two tools are alm ost com plemen tary in their strengths and weaknesses: neural nets are very good in noisy-data processing but weak in high-level reasoning, production systems exhibit reasonably good performance in high-level reasoning but are weak in handling imprecise and uncertain data. Petri nets, another widely used paradigm, are useful in modelling concurrent processes and sim ulation of discrete pro cesses. Co nseque ntly, som e research ers are trying to com bine these tools in ord er to util ize the strength of each system. This paper describes the way of simulating Petri nets in the expert system shell McESE.