Generalized Closed World Assumption is ng - complete
نویسندگان
چکیده
منابع مشابه
Generalized Closed World Reasoning in Description Logics with Extended Domain Closure
Generalized closed world reasoning allows for the assumption of a specified maximal set of negated atomic assertions retaining the consistency of an indefinite knowledge base. In this paper, a generalized closed world assumption (GCWA) is specified for the description logic ALCN and all of its sublanguages, provided that the terminological component is eliminable. In certain situations, by appl...
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We study the semantics of disjunctive logic programs that simultaneously contain multiple kinds of default negations. We introduce operators not G , not W , and not STB in the language of logic programs to represent the Generalized Closed World Assumption, the Weak Generalized Closed World Assumption, and the stable negation, respectively. The notion of stratiication involving diierent kinds of...
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Standard databases convey Reiter’s closed-world assumption that an atom not in the database is false. This assumption is relaxed in locally closed databases that are sound but only partially complete about their domain. One of the consequences of the weakening of the closed-world assumption is that query answering in locally closed databases is undecidable. In this paper, we develop efficient a...
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The computational complexity of a number of problems relating to minimal models of deductive databases is considered. In particular, it is shown that Minker's gener-alised closed world assumption (GCWA) is P P 1-complete for stratiied propositional databases and P P 2-complete for non-stratiied databases. The structure of minimal models is also examined using the notion of a weak deduction tree...
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This paper investigates a consistent versions cwaS of sometimes inconsistent Reiter’s closed world assumption cwa, proving (theorem 4.3) that for every ∀-sentence φ and for every ∀-theory Σ, φ ∈ cwaS(Σ) iff Σ `min φ. A relativized version of this characterization (theorem 7.3) remains valid if not all relations are subject to minimization. Moreover, the paper relates cwaS to cwa and to Minker’s...
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