M. Dalal. Anytime families of tractable propositional reasoners. In International Symposium on Artificial Intelligence and Mathematics AI/MATH-96, pages 42- 45, 1996. Extended version submitted to Annals of Mathematics and Artificial Intelligence.  Home/Search   Document Details and Download   Summary   Related Articles   Check

....a theory into another one for which deduction is faster. According to Selman : Kautz [161] we do not approximate the inference procedure, rather we simplify the theory using a Horn relaxation of the problem for which fast algorithms are known. Similar forms of compilation proposed by Dalal [37] or del Val [47] use target theories for which boolean constraints propagation and unit resolution respectively are complete procedure. Compilation is a one off processing of a set of formulae, and doesn t exactly match the intuition of approximation of logical consequence as an incremental ....

....a set of formulae, and doesn t exactly match the intuition of approximation of logical consequence as an incremental process: if the procedure fails we must resort to the original calculus for an answer. Another approach, proposed initially by Rantala [147] and later on by Dalal and Etheringthon [37, 39], uses syntactic approximation of inference procedure and can be made incremental by an essential use of cut or, in more constructive form, by iterated steps of knowledge compilation as done by Dalal [37] and del Val [47] The major problem of both approaches is that the compilation process leads ....

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M. Dalal. Anytime families of tractable propositional reasoners. In International Symposium on Artificial Intelligence and Mathematics AI/MATH-96, pages 42- 45, 1996. Extended version submitted to Annals of Mathematics and Artificial Intelligence.

....automatically producing multimedia briefings [ 1] that meet the information needs of a variety of caregivers, including different specialists and nurses. Through the use of natural language generation [2] knowledge based graphics generation [3] and knowledge representation and reasoning systems [4], we are developing an experimental system that can dynamically determine at run time what information to include in a multimedia briefing, how to divide this information among different media, and the form of the language and graphics used. In the following sections, we first provide an overview ....

....component, it is conveyed to the constraint solver, which determines the consistency and returns the result back. The system component may decide to backtrack in case of inconsistency. Since determining inconsistency is intractable in general, the constraint solver uses an anytime algorithm [4] that sometimes returns the result maybe consistent . The component that generated the constraint may decide to wait for a definite answer, or may proceed further making some tentative assumption of its own, which it must be willing to revoke when a differ ent definite answer is obtained. Given ....

M. Dalal. Anytime families of tractable propositional reasoners. In Fourth Int. Syrup. on Artificial Intelligence and Mathematics' (AI/MATH-96), 42- 45, Florida, 1996.

.... Sigma there is some i such that Sigma 2 Pi i . Propositions 2 and 3 do have some limitations. There is, first, the recognition 9 problem. No polynomial time algorithm is known for recognizing extended Horn or balanced theories, nor the hierarchies of tractable inference relations defined in [7]; and recognition of the hierarchy renamable generalized Horn is NP hard [11] Thus even if Sigma or Sigma [ C is, say, extended Horn, we cannot infer the satisfiability of Sigma [ C from the failure to unit refute it; for this we need to know (recognize) that Sigma [ C is extended Horn. ....

Mukesh Dalal. Anytime families of tractable propositional reasoners. In Proceedings of the Fourth International Symposium on Artificial Intelligence and Mathematics, pages 42--45, 1996.

.... an exact proof of a classical theorem is too hard, why not looking for an approximate one To fill this gap, a number of approximation methods for logical consequence have been developed in AI: knowledge compilation [22] semantical approximations [4,15,16,21] and syntactic anytime reasoners [7,6,8]. Knowledge compilation or vivification [7,22] is a preprocessing step to transform a theory into another one for which deduction is faster: Horn theories in [22] and boolean constraints propagation in [7] So it doesn t exactly match the intuition of approximation as an incremental process. ....

....or vivification [7,22] is a preprocessing step to transform a theory into another one for which deduction is faster: Horn theories in [22] and boolean constraints propagation in [7] So it doesn t exactly match the intuition of approximation as an incremental process. Syntactic approximation [7,6,8] is incremental but its essential use of cut (for the incremental steps of the construction) forces to use knowledge compilation for a constructive formulation. These techniques change the formulae of the theory, and lead to an exponential blow up of the approximating theories [4,7,22] Logical ....

[Article contains additional citation context not shown here]

M. Dalal. Anytime families of tractable propositional reasoners. In International Symposium on Artificial Intelligence and Mathematics AI/MATH-96, pages 42-- 45, 1996. Extended version submitted to Annals of Mathematics and Artificial Intelligence.

....(RFP) a quadratic time method that infers exactly the same literals as CNF BCP, for which we also have a model theoretic semantics. BCP, FP, and RFP are all incomplete reasoners. We will present a technique that extends them to families of increasingly complete, sound, and tractable reasoners [4, 3, 6]. Our technique for generating these anytime families is based on restricting the length of the clauses used in chaining (Modus Ponens) We will also provide model theoretic semantics for the reasoners in the anytime family based on BCP [7] We will present results of some preliminary experiments ....

M. Dalal, `Anytime families of tractable propositional reasoners', in Fourth International Symposium on Artificial Intelligence and Mathematics (AI/MATH-96), pp. 42--45, Florida, (1996).

.... Dean 1988) They are complete reasoners that provide partial answers even if stopped prematurely; the degree of completeness of the answer improves with the time used in computing the answer. They are often used for providing a quick first cut to a problem, which can be later improved. In (Dalal 1996b; 1996a) we presented a family 0 ; 1 ; of reasoners such that each k is sound and tractable, each k 1 is at least as complete as k , and each theory has a complete reasoner k for reasoning with it. Such a family is called an anytime family of reasoners, since given any reasoning task, one can presumably start ....

Dalal, M. 1996b. Anytime families of tractable propositional reasoners. In Fourth International Symposium on Artificial Intelligence and Mathematics (AI/MATH-96), 42--45.

....reasoners [3] They are complete reasoners that provide partial answers even if stopped prematurely; the degree of completeness of the answer improves with the time used in computing the answer. They are often used for providing a quick first cut to a problem, which can be later improved. [12] presented a family 0 ; 1 ; of reasoners such that each i is sound and tractable, each i 1 is at least as complete as i , and each theory has a complete reasoner i for reasoning with it. Such a family is called an anytime family of reasoners, since given any reasoning task, one ....

....of this family are given in Section 6) The two anytime families cited above are incomparable, that is, different inferences are made at corresponding levels. Although the reasoners in [6] were specified using a model theoretic semantics, no model theoretic semantics is known for the reasoners in [12] which have been specified using inference rules. This is a serious problem, since the importance of model theoretic semantics for reasoners has been convincingly established in several papers (c.f. 19] In this paper, we provide a model theoretic semantics for the anytime family BCP = ....

[Article contains additional citation context not shown here]

M. Dalal, `Anytime families of tractable propositional reasoners', in Fourth International Symposium on Artificial Intelligence and Mathematics (AI/MATH-96), pp. 42--45, Florida, (1996).

.... for determining consistency of temporal constraint networks based on Allen s interval based framework [All83] The temporal network is first translated into a clausal theory in propositional logic [Men64] whose satisfiability is then determined using an anytime family of tractable reasoners [Dal96]. Anytime reasoners are complete reasoners that provide partial answers even if stopped prematurely; the completeness of the answer improves with the time used in computing the answer. Our anytime family 0 ; 1 ; is built upon clausal boolean constraint propagation (BCP) McA90] a ....

M. Dalal. Anytime families of tractable propositional reasoners. In Fourth International Symposium on Artificial Intelligence and Mathematics (AI/MATH-96), pages 42--45, Florida, 1996.

....ours, they do not consider arbitrary grouping and multiple occurrences of literals. Cadoli and Schaerf [SC95] obtained several reasoners by parameterizing j= RP by sets of propositions. However, we have shown [Dal95] that none of their incomplete reasoners is stronger than j . In a related work [Dal96] we have extended j to an anytime family 0 ; 1 ; of reasoners such that each i is tractable, each i 1 is at least as complete as i , and each theory has a i complete for reasoning with it. By using term rewriting systems, we have also extended these reasoners to non clausal ....

M. Dalal. Anytime families of tractable propositional reasoners. In Fourth International Symposium on Artificial Intelligence and Mathematics (AI/MATH-96), pages 42-- 45, Florida, 1996.

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Dalal, M. 1996a. Anytime families of tractable propositional reasoners. In Proceedings of the Fourth International Symposium on Artificial Intelligence and Mathematics (AI/MATH-96), 42--45.

No context found.

Dalal, M. 1996a. Anytime families of tractable propositional reasoners. In Proc. of AI and Math. (AI/MATH-96), 42--45.

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