Abstract

An application shell provides a domain independent diagnostic problem solver comprised of a knowledge base. The knowledge base includes a plurality of failure mode schemata arranged in a causal hierarchy from observable failure modes to failure modes having a repair procedure; a plurality of rule schemata related to certain of said failure mode schemata; a plurality of datum schemata for gathering data about the system under investigation, the information being used to determine the applicability of said rule schemata; and a plurality of repair procedure schemata each being related to one of the failure mode schemata having a repair procedure. A problem solver is capable of forward chaining through the knowledge base and backward chaining through the failure mode schemata based on the rules, the forward chaining, and the hierarchical arrangement of failure mode schemata so as to change the focus from one failure mode schema to another failure mode schema deeper within the hierarchical arrangement without having to focus upon any intermediate schemata to thereby locate an appropriate repair procedure schema.

Other References

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