Abductive logicprogramming (ALP) and disjunctive logic programming (DLP) are two different extensions of logicprogramming. This paper investigates the relationship between ALP and DLP from the program transformation...
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Abductive logicprogramming (ALP) and disjunctive logic programming (DLP) are two different extensions of logicprogramming. This paper investigates the relationship between ALP and DLP from the program transformation viewpoint. It is shown that the belief set semantics of an abductive program is expressed by the answer set semantics and the possible model semantics of a disjunctive program. In converse, the possible model semantics of a disjunctive program is equivalently expressed by the belief set semantics of an abductive program, while such a transformation is generally impossible for the answer set semantics. Moreover, it is shown that abductive disjunctive programs are always reducible to disjunctive programs both under the answer set semantics and the possible model semantics. These transformations are verified from the complexity viewpoint, The results of this paper turn out that ALP and DLP are just different ways of looking at the same problem if we choose an appropriate semantics. (C) 2000 Elsevier Science Inc. All rights reserved.
disjunctive logic programming (DLP) is an advanced formalism for knowledge representation and reasoning. The language of DLP is very expressive and supports the representation of problems of high computational complex...
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disjunctive logic programming (DLP) is an advanced formalism for knowledge representation and reasoning. The language of DLP is very expressive and supports the representation of problems of high computational complexity (specifically, all problems in the complexity class Sigma(P)(2) = Np-NP). The DLP encoding of a large variety of problems is often very concise, simple, and elegant. In this paper, we explain the computational process commonly performed by DLP systems, with a focus on search space pruning, which is crucial for the efficiency of such systems. We present two suitable operators for pruning (Fitting's and Well-founded), discuss their peculiarities and differences with respect to efficiency and effectiveness. We design an intelligent strategy for combining the two operators, exploiting the advantages of both. We implement our approach in DLV - the state-of-the-art DLP system - and perform some experiments. These experiments show interesting results, and evidence how the choice of the pruning operator affects the performance of DLP systems.
This paper gives a brief high-level description of what has been done in the disjunctive logic programming-project (funded by Deutsche Forschungs-Gemeinschaft), undertaken by the University of Koblenz, Germany since J...
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This paper gives a brief high-level description of what has been done in the disjunctive logic programming-project (funded by Deutsche Forschungs-Gemeinschaft), undertaken by the University of Koblenz, Germany since July 1995. Presented are the main ideas, the implemented systems and how to access them, and the relevant papers are cited. This paper also serves as a brief survey of the current status of disjunctive logic programming by highlighting important developments and provides enough pointers for further reading.
In this paper we introduce the logicprogramming language disjunctive Chronology which combines the programming paradigms of temporal and disjunctive logic programming. disjunctive Chronolog is capable of ex pressing ...
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In this paper we introduce the logicprogramming language disjunctive Chronology which combines the programming paradigms of temporal and disjunctive logic programming. disjunctive Chronolog is capable of ex pressing dynamic behaviour as well as uncertainty, two notions that are very common in a variety of real systems. We present the minimal temporal model semantics and the fixpoint semantics for the new programming language and demonstrate their equivalence. We also show how proof procedures developed for disjunctivelogic programs can be easily extended to apply to disjunctive Chronolog programs.
An extension of an abstract argumentation framework is introduced that provides a direct representation of global conflicts between sets of arguments. The extension, called collective argumentation, turns out to be su...
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An extension of an abstract argumentation framework is introduced that provides a direct representation of global conflicts between sets of arguments. The extension, called collective argumentation, turns out to be suitable for representing semantics of disjunctivelogic programs. Collective argumentation theories are shown to possess a four-valued semantics, and are closely related to multiple-conclusion (Scott) consequence relations. Two special kinds of collective argumentation, positive and negative argumentation, are considered in which the opponents can share their arguments. Negative argumentation turns out to be especially appropriate for analysing stable sets of arguments. Positive argumentation generalizes certain alternative semantics for logic programs.
disjunctive logic programming is nowadays a mature formalism which has been successfully applied to a variety of practical problems, such as information integration, knowledge representation, planning, diagnosis, opti...
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disjunctive logic programming is nowadays a mature formalism which has been successfully applied to a variety of practical problems, such as information integration, knowledge representation, planning, diagnosis, optimization and configuration. Although current DLP systems have been extended in many directions, they still miss features which may be helpful towards industrial applications, like the capability of quickly introducing new predefined constructs or of dealing with modules. Indeed, in spite of the fact that a wide literature about modular logicprogramming is known, code reusability has never been considered as a critical point in disjunctive logic programming. In this work we extend disjunctive logic programming, under stable model semantics, with the notion of "template" predicates. A template predicate may be instantiated to an ordinary predicate by means of template atoms, thus allowing to define reusable modules, to define new constructs and aggregates without any syntactic limitation.
disjunctive logic programming (DLP) with stable model semantics is a powerful nonmonotonic formalism for knowledge representation and reasoning. Reasoning with DLP is harder than with normal (boolean OR-free) logic pr...
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disjunctive logic programming (DLP) with stable model semantics is a powerful nonmonotonic formalism for knowledge representation and reasoning. Reasoning with DLP is harder than with normal (boolean OR-free) logic programs, because stable model checking-deciding whether a given model is a stable model of a propositional DLP program-is co-NP-complete, while it is polynomial for normal logic programs. This paper proposes a new transformation Gamma(M) (P), which reduces stable model checking to UNSAT-i.e., to deciding whether a given CNF formula is unsatisfiable. The stability of a model M of a program P thus can be verified by calling a Satisfiability Checker on the CNF formula Gamma(M) (P). The transformation is parsimonious (i.e., no new symbol is added), and efficiently computable, as it runs in logarithmic space (and therefore in polynomial time). Moreover, the size of the generated CNF formula never exceeds the size of the input (and is usually much smaller). We complement this transformation with modular evaluation results, which allow for efficient handling of large real-world reasoning problems. The proposed approach to stable model checking has been implemented in DLV-a state-of-the-art implementation of DLP. A number of experiments and benchmarks have been run using SATZ as Satisfiability checker. The results of the experiments are very positive and confirm the usefulness of our techniques. (C) 2003 Elsevier B.V. All rights reserved.
作者:
Tsouanas, ThanosUniv Lyon
Ecole Normale Super Lyon Lab Informat Parallelisme LIP UMR CNRS ENS Lyon UCBL INRIA 5668 F-69364 Lyon 07 France
Denotational semantics of logicprogramming and its extensions (by allowing negation, disjunctions, or both) have been studied thoroughly for many years. In 1998, a game semantics was given to definite logic programs ...
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Denotational semantics of logicprogramming and its extensions (by allowing negation, disjunctions, or both) have been studied thoroughly for many years. In 1998, a game semantics was given to definite logic programs by Di Cosmo, Loddo, and Nicolet, and a few years later it was extended to deal with negation by Rondogiannis and Wadge. Both approaches were proven equivalent to the traditional semantics. In this paper we define a game semantics for disjunctivelogic programs and prove soundness and completeness with respect to the minimal model semantics of Minker. The overall development has been influenced by the games studied for PCF and functional programming in general, in the styles of Abramsky-Jagadeesan-Malacaria and Hyland-Ong-Nickau. (C) 2013 Elsevier B.V. All rights reserved.
This paper extends the result of Caminada and Schulz [6,7] by showing that assumption-based argumentation can represent not only normal logic programs, but also disjunctivelogic programs. For this, we incorporate a p...
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ISBN:
(纸本)9783030302443;9783030302436
This paper extends the result of Caminada and Schulz [6,7] by showing that assumption-based argumentation can represent not only normal logic programs, but also disjunctivelogic programs. For this, we incorporate a previous work of ours (see [19,20]), in which reasoning with assumption-based argumentation frameworks is based on certain core logics and the strict/defeasible assumptions may be arbitrary formulas in those logics. In our case, the core logic respects some inference rules for disjunction, which allows disjunctions in the heads of the programs' rules to be handled properly.
Impressive work has been done in the last;years concerning the meaning of negation and disjunction in logic programs, but most of this research concentrated on propositional programs only. While it suffices to conside...
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ISBN:
(纸本)3540628436
Impressive work has been done in the last;years concerning the meaning of negation and disjunction in logic programs, but most of this research concentrated on propositional programs only. While it suffices to consider the propositional case for investigating general properties and the overall behaviour of a semantics, we feel that for real applications and for computational purposes an implementation should be able to handle first-order programs without grounding them. In this paper we present a theoretical framework by defining a calculus of program transformations that apply directly to rules with variables and function symbols. Our main results are that (1) this calculus is confluent for arbitrary programs, (2) for finite ground programs it is equivalent to a terminating calculus introduced by Brass and Dir (1995), and (3) it approximates a generalisation of D-WFS for arbitrary programs. We achieve this by transforming program rules into rules with equational constraints thereby using heavily methods and techniques from constraint logicprogramming. In particular, disconnection-methods play a crucial role. In principle, any constraint theory known from the field of constraint logicprogramming can be exploited in the context of nonmonotonic reasoning, not only equational constraints over the Herbrand domain. However, the respective constraint solver must be able to treat negative constraints of the considered constraint domain. In summary, this work yields the basis for a general combination of two paradigms: constraint logicprogramming and non-monotonic reasoning.
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