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PREPARE: A Tool for Knowledge Base Verification
December 1994 (vol. 6 no. 6)
pp. 983-989

The knowledge base is the most important component in a knowledge-based system. Because a knowledge base is often built in an incremental, piecemeal fashion, potential errors may be inadvertently brought into it. One of the critical issues in developing reliable knowledge-based systems is how to verify the correctness of a knowledge base. The paper describes an automated tool called PREPARE for detecting potential errors in a knowledge base. PREPARE is based on modeling a knowledge base by using a predicate/transition net representation. Inconsistent, redundant, subsumed, circular, and incomplete rules in a knowledge base are then defined as patterns of the predicate/transition net model, and are detected through a syntactic pattern recognition method. The research results to date have indicated that: the methodology ran be adopted in knowledge-based systems where logic is used as knowledge representation formalism; the tool can be invoked at any stage of the system's development, even without a fully functioning inference engine; the predicate/transition net model of knowledge bases is easy to implement and provides a clear and understandable display of the knowledge to be used by the system.

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Index Terms:
knowledge based systems; program verification; semantic networks; pattern recognition; PREPARE; knowledge base verification; correctness; reliable knowledge-based systems; automated tool; potential errors; predicate/transition net representation; incomplete rules; syntactic pattern recognition method; logic; fully functioning inference engine
Citation:
D. Zhang, D. Nguyen, "PREPARE: A Tool for Knowledge Base Verification," IEEE Transactions on Knowledge and Data Engineering, vol. 6, no. 6, pp. 983-989, Dec. 1994, doi:10.1109/69.334887
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