MANTRA: a shell for hybrid knowledge representation

A shell is presented for hybrid knowledge representation. This system supports four different knowledge representation formalisms: first-order logic, terminological language, semantic networks, and production systems. The system automatically supports hybrid inferences taking into account the knowledge represented in different formalisms. All the algorithms involved in the inferences, supported by the system, are decidable, and have the property of being sound and complete according to a four-valued semantics. Besides these facilities, the shell allows the user to represent procedural knowledge of a domain using the primitives embedded at the heuristic level. The system has been implemented in Common Lisp, and makes use of an object-oriented extension for this language.<
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