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Well-Founded Semantics, Generalized

by Melvin C. Fitting - In Proceedings of International Symposium on Logic Programming , 1991
"... Classical fixpoint semantics for logic programs is based on the TP immediate consequence operator. The Kripke/Kleene, three-valued, semantics uses #P , which extends TP to Kleene's strong three-valued logic. Both these approaches generalize to cover logic programming systems based on a wide cla ..."
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class of logics, provided only that the underlying structure be that of a bilattice. This was presented in earlier papers. Recently well-founded semantics has become influential for classical logic programs. We show how the well-founded approach also extends naturally to the same family

Unfolding the Well-founded Semantics

by Matthias Wendt - Journal of Electrical Engineering, Slovak Academy of Sciences , 2002
"... We study the xpoint completion, proposed by Dung and Kanchanasut in [DK89]. The fixpoint completion is a program transformation - it performs a kind of unfolding of recursion through positive atoms in the clauses of a program f that was shown to preserve the semantics of a program in a certain sense ..."
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sense. We generalize the results from [DK89] in some ways and show how the handling of negation is transformed by the fixpoint completion. We thereby obtain a more clarified view of both the fixpoint completion itself and the relationship between well-founded and Fitting semantics.

Aggregation and Well-Founded Semantics

by Mauricio Osorio, Bharat Jayaraman, Sta Catarina Martir , 1997
"... . Set-grouping and aggregation are powerful non-monotonic operations of practical interest in database query languages. We consider the problem of expressing aggregation via negation as failure (NF). We study this problem in the framework of partial-order clauses introduced in [JOM95]. We show a tra ..."
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translation of partial-order programs to normal programs that is very natural: Any cost-monotonic partial-order program P becomes a stratified normal program transl(P) such that the declarative semantics of P is equivalent to the stratified semantics of transl(P). The ability to effect such a translation

Extended Well-Founded Semantics in Bilattices

by Daniel Stamate , 2005
"... One of the most used assumptions in logic programming and deductive databases is the so-called Closed World Assumption (CWA), according to which the atoms that cannot be inferred from the programs are considered to be false (i.e. a pessimistic assumption). One of the most successful semantics of con ..."
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of conventional logic programs based on the CWA is the well-founded semantics. However, the CWA is not applicable in all circumstances when information is handled. That is, the well-founded semantics, if conventionally defined, would behave inadequately in different cases. The solution we adopt in this paper

Loop Checking and the Well-Founded Semantics

by Vladimir Lifschitz, Norman McCain, Teodor C. Przymusinski, Robert F. Stärk - Proceedings of the 12th International Conference on Logic Programming, Japan , 1995
"... . Using a calculus of goals, we define the success and failure of a goal for propositional programs in the presence of loop checking. The calculus is sound with respect to the well-founded semantics; for finite programs, it is also complete. A Prolog-style proof search strategy for a modification of ..."
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. Using a calculus of goals, we define the success and failure of a goal for propositional programs in the presence of loop checking. The calculus is sound with respect to the well-founded semantics; for finite programs, it is also complete. A Prolog-style proof search strategy for a modification

Well-Founded Semantics for Default Logic

by Gerhard Brewka, Georg Gottlob , 1997
"... Default logic is one of the most popular approaches to model defeasible reasoning. Nevertheless, there are a number of problems with Reiter's original semantics that have led to the investigation of alternative approaches. In particular, Baral/Subrahmanian and Przymusinska/Przymusinski have ..."
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investigated generalizations of well-founded semantics for normal logic programs to default logic. These

A Tutorial on the Well-Founded Semantics

by Allen Van Gelder , 1997
"... The well-founded semantics for "normal" logic programs is described using the alternating fixpoint construction as the basis. The presentation is informal. The semantics is motivated and illustrated through examples, and is compared briefly with earlier semantics for negation. Extensions ..."
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The well-founded semantics for "normal" logic programs is described using the alternating fixpoint construction as the basis. The presentation is informal. The semantics is motivated and illustrated through examples, and is compared briefly with earlier semantics for negation. Extensions

Logical foundations of well-founded semantics

by Pedro Cabalar, Sergei Odintsov, David Pearce, Juan Carlos - In P , 2006
"... We propose a solution to a long-standing problem in the foun-dations of well-founded semantics (WFS) for logic programs. The problem addressed is this: which (non-modal) logic can be considered adequate for well-founded semantics in the sense that its minimal models (appropriately defined) coin-cide ..."
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We propose a solution to a long-standing problem in the foun-dations of well-founded semantics (WFS) for logic programs. The problem addressed is this: which (non-modal) logic can be considered adequate for well-founded semantics in the sense that its minimal models (appropriately defined) coin

Decidability Under the Well-Founded Semantics ⋆

by Natalia Cherchago, Pascal Hitzler, Steffen Hölldobler
"... Abstract. The well-founded semantics (WFS) for logic programs is one of the few major paradigms for closed-world reasoning. With the advent of the Semantic Web, it is being used as part of rule systems for ontology reasoning, and also investigated as to its usefulness as a semantics for hybrid syste ..."
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Abstract. The well-founded semantics (WFS) for logic programs is one of the few major paradigms for closed-world reasoning. With the advent of the Semantic Web, it is being used as part of rule systems for ontology reasoning, and also investigated as to its usefulness as a semantics for hybrid

Comparing Disjunctive Well-founded Semantics ⋆

by Matthias Knorr, Pascal Hitzler
"... Abstract. While the stable model semantics, in the form of Answer Set Programming, has become a successful semantics for disjunctive logic programs, a corresponding satisfactory extension of the well-founded semantics to disjunctive programs remains to be found. The many current proposals for such a ..."
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Abstract. While the stable model semantics, in the form of Answer Set Programming, has become a successful semantics for disjunctive logic programs, a corresponding satisfactory extension of the well-founded semantics to disjunctive programs remains to be found. The many current proposals
Results 1 - 10 of 1,431