An Approach to Build a Knowledge Base for Reactor Accident Diagnostic Expert System

In the development of a rule based expert system, one of key issues is how to acquire knowledge and to build knowledge base (KB). On building the KB of DISKET 1),2), which is an expert system for nuclear reactor accident diagnosis developed in JAERI, several problems have been experienced as follows. To write rules is a time consuming task, and it is difficult to keep the objectivity and consistency of rules as the number of rules increase. Further, certainty factors (CFs) must be often determined according to engineering judgement, i.e. empirically or intuitively. A systematic approach was attempted to handle these difficulties and to build an objective KB efficiently.