Inference in expert systems based on complete multivalued logic. (English) Zbl 0665.68077

The essence of presumed approach towards reasoning in cases of uncertainty consists in assuming the knowledge base as a fuzzy axiomatic theory, i.e., a set of formulae in which each formula is equipped with a weight specifying the degree of membership to the fuzzy set of axioms of the theory. The task of the inference mechanism in such a case is to determine the degree to which each goal logically follows from this theory, and also other presumptions (the user’s answers during the consultation). As a result of these reflections a logical inference mechanism has been designed which was implemented and tested in the system of automatic consultations (SAK). One of the advantages of this approach is the possibility of a natural insertion of contexts into knowledge base which has been used for improvement of the work of the SAK-OPTIMALI expert system.


68T37 Reasoning under uncertainty in the context of artificial intelligence
68T35 Theory of languages and software systems (knowledge-based systems, expert systems, etc.) for artificial intelligence
03B52 Fuzzy logic; logic of vagueness
03B50 Many-valued logic
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