Integration of uncertainty management systems with object-oriented expert system building tools

This paper addresses the issues of integrating uncertainty management systems (UMSs) with object-oriented expert system building tools (ESBTs), including knowledge representation, propagation and combination and inheritance of uncertainty characteristics. Uncertainty characteristics such as certainty value and threshold are suggested to be represented by properties. MYCIN type of UMS is used to demonstrate how these properties facilitate propagation and combination in object-oriented ESBTs. Propagation concerns the computation of certainty values from AND, OR, and NOT logic, and IF THEN rule; combination concerns the computation of certainty values when a fact is asserted to the fact base with the same fact. In addition, precedence rules determining the precedence of inheritance are investigated for their appropriateness, when UMSs are integrated with object-oriented ESBTs. Alternative rules are proposed to reflect the role of uncertainty characteristics in object-oriented ESBTs