Abstract
Platypus is a constraint-based expert system shell for diagnosis, synthesis and other recognition tasks. Next-generation expert systems will augment the rule-based approach with more powerful knowledge representations and more efficient search mechanisms. In Platypus, a object-centered knowledge representation produces explicit descriptions of the entities recognized in the task domain, their identifying parameters and the semantic constraints that exist among the entities. Constraint propagation is used to refine these descriptions dynamically during recognition, thereby limiting search. A truth maintenance subsystem supports the dependency directed backtracking of the reasoning process. Platypus is implemented as an extension to the Scheme programming language. This paper outlines some of the programming aspects of Platypus. The classic n-queens problem is used to explain the reasoning architecture and its programming language.
This research was conducted while the author was at Tektronix Laboratoires, Beaverton, Oregon, USA 97077.
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© 1990 Springer-Verlag Berlin Heidelberg
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Havens, B. (1990). The platypus expert system shell. In: Ramani, S., Chandrasekar, R., Anjaneyulu, K.S.R. (eds) Knowledge Based Computer Systems. KBCS 1989. Lecture Notes in Computer Science, vol 444. Springer, Berlin, Heidelberg. https://doi.org/10.1007/BFb0018372
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DOI: https://doi.org/10.1007/BFb0018372
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