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WFS + Branch and Bound = Stable Models
June 1995 (vol. 7 no. 3)
pp. 362-377

Abstract—Though the semantics of nonmonotonic logic programming has been studied extensively, relatively little work has been done on operational aspects of these semantics. In this paper, we develop techniques to compute the well-founded model of a logic program. We describe a prototype implementation and show, based on experimental results, that our technique is more efficient than the standard alternating fixpoint computation. Subsequently, we develop techniques to compute the set of all stable models of a deductive database. These techniques first compute the well-founded semantics and then use an intelligent branch and bound strategy to compute the stable models. We report on our implementation, as well as on experiments that we have conducted on the efficiency of our approach.

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Index Terms:
Logic programming, deductive databases, nonmonotonic reasoning, negation by failure.
V.s. Subrahmanian, Dana Nau, Carlo Vago, "WFS + Branch and Bound = Stable Models," IEEE Transactions on Knowledge and Data Engineering, vol. 7, no. 3, pp. 362-377, June 1995, doi:10.1109/69.390244
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