The manipulation of time-varying dynamic variables using the rule modification method and performance-index in NPP accident diagnostic expert systems

When an expert system is being developed for nuclear power plant (NPP) accident diagnosis, the most difficult problem is the manipulation of the time-varying dynamic variables. To meet this need, the authors propose modification of the rules for accident diagnosis when plant parameters and conditions are varying. In addition to the rule-modification method, a pattern-matching method using the performance index is suggested. This system also uses the results of transient analysis and accident analysis codes as a database. To simulate this expert system, PROLOG was used to construct the knowledge base. The inherent backtracking inference strategy was used for the inference engine. Feedwater line piping failure was selected for system verification.<
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