The Gelfond-Lifschitz operator associated with a logic program (and likewise the operator associated with default theories by Reiter) exhibits oscillating behavior. In the case of logic programs, there is always at le...
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The Gelfond-Lifschitz operator associated with a logic program (and likewise the operator associated with default theories by Reiter) exhibits oscillating behavior. In the case of logic programs, there is always at least one finite, nonempty collection of Herbrand interpretations around which the Gelfond-Litschitz operator 'bounces around'. The same phenomenon occurs with default logic when Reiter's operator GAMMA(DELTA) is considered. Based on this, a 'stable class' semantics and 'extension class' semantics has been proposed. The main advantage of this semantics was that it was defined for all logic programs (and default theories), and that this definition was modelled using the standard operators existing in the literature such as Reiter's GAMMA(DELTA) operator. In this paper our primary aim is to prove that there is a very interesting duality between stable class theory and the well-founded semantics for logic programming. In the stable class semantics, classes that were minimal with respect to Smyth's power-domain ordering were selected. We show that the well-founded semantics precisely corresponds to a class that is minimal w.r.t. Hoare's power domain ordering: the well-known dual of Smyth's ordering. Besides this elegant duality, this immediately suggests how to define a well-founded semantics for default logic in such a way that the dualities that hold for logic programming continue to hold for default theories. We show how the same technique may be applied to 'strong' autoepistemic logic: the logic of strong expansions proposed by Marek and Truszczynski.
LP (logic programming) has been successfully applied to knowledge discovery in many fields. The execution of the LP is based on the evaluation of the first order predicate. Usually the information involved in the pred...
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LP (logic programming) has been successfully applied to knowledge discovery in many fields. The execution of the LP is based on the evaluation of the first order predicate. Usually the information involved in the predicates are local and homogenous, thus the evaluation process is relatively simple. However, the evaluation process become much more complicated when applied to KDD on the Internet where the information involved in the predicates maybe heterogeneous and distributed over many different sits. Therefor, we try to attack the problem in a multi agent system's framework so that the logic program can be written in a site independent style and deal easily with heterogeneous represented information.
The proceedings contain 37 papers. The topics discussed include: coinductive logic programming and its applications;multi-paradigm declarative languages;logic programming for knowledge representation;minimal logic pro...
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ISBN:
(纸本)9783540746089
The proceedings contain 37 papers. The topics discussed include: coinductive logic programming and its applications;multi-paradigm declarative languages;logic programming for knowledge representation;minimal logic programs;logic programming approach to automata-based decision procedures;a logic programming framework for combinatorial circuit synthesis;observable confluence for constraint handling rules;declarative diagnosis of temporal concurrent constraint programs;resource-oriented deadlock analysis;automatic correctness proofs for logic program transformations;declarative debugging of missing answers in constraint functional-logic programming;visual logic programming method based on structural analysis and design technique;advanced techniques for answer set programming;modular answer set programming;and universal timed concurrent constraint programming.
The Conference materials contain 61 papers on logic programming. Theory and foundations, applications of logic programming, implementations, machines and architectures, programming methodology and tools, relations wit...
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The Conference materials contain 61 papers on logic programming. Theory and foundations, applications of logic programming, implementations, machines and architectures, programming methodology and tools, relations with software engineering, relations with deductive databases, relations with artificial intelligence, extensions, constraints, and logical languages for parallelism are the main topics covered.
Model transformation by example [18] is a novel approach in model-driven software engineering to derive model transformation rules from an initial prototypical set of interrelated source and target models, which descr...
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ISBN:
(纸本)1595934804;9781595934802
Model transformation by example [18] is a novel approach in model-driven software engineering to derive model transformation rules from an initial prototypical set of interrelated source and target models, which describe critical cases of the model transformation problem in a purely declarative way. In the current paper, we automate this approach using inductive logic programming [14] which aims at the inductive construction of first-order clausal theories from examples and background knowledge. Copyright 2007 ACM.
We present a method for preprocessing Prolog programs so that their operational semantics will be given by the first-order predicate calculus. Most Prolog implementations do not use a full unification algorithm, for e...
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We present a method for preprocessing Prolog programs so that their operational semantics will be given by the first-order predicate calculus. Most Prolog implementations do not use a full unification algorithm, for efficiency reasons. The result is that it is possible to create terms having loops in them, whose semantics is not adequately described by first-order logic. Our method finds places where such loops may be created, and adds tests to detect them. This should not appreciably slow down the execution of most Prolog programs.
We build on an existing a term-sequent logic for the lambda-calculus. We formulate a general sequent system that fully integrates alpha beta eta-reductions between untyped lambda-terms into first order logic. We prove...
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We build on an existing a term-sequent logic for the lambda-calculus. We formulate a general sequent system that fully integrates alpha beta eta-reductions between untyped lambda-terms into first order logic. We prove a cut-elimination result and then offer an application of cut-elimination by giving a notion of uniform proof for lambda-terms. We suggest how this allows us to view the calculus of untyped alpha beta-reductions as a logic programming language (as well as a functional programming language, as it is traditionally seen).
This paper describes the role of logic programming in the Fifth Generation Computer Project. We started the project with the conjecture that logic programming is the “bridge” connecting knowledge information process...
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This paper describes the role of logic programming in the Fifth Generation Computer Project. We started the project with the conjecture that logic programming is the “bridge” connecting knowledge information processing and parallel computer architecture. Four years have passed since we started the project, and now we can say that this conjecture has been substantially confirmed. The paper gives an overview of the developments which have reinforced this foundational conjecture and how our “bridge” is being realized.
The paper describes a simple compiler analysis method for determining the “weight” of procedures in parallel logic programming languages. Using Flat Guarded Horn Clauses (FGHC) as an example, the analysis algorithm ...
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The paper describes a simple compiler analysis method for determining the “weight” of procedures in parallel logic programming languages. Using Flat Guarded Horn Clauses (FGHC) as an example, the analysis algorithm is described. Consideration of weights has been incorporated in the scheduler of a real-parallel FGHC emulator running on the Sequent Symmetry multiprocessor. Alternative demand-distribution methods are discussed, includingoldest-first andheaviest-first distributions. Performance measurements, collected from a group of non-trivial benchmarks on eight processors, show that the new schemes donot perform significantly faster than conventional distribution methods. This result is attributed to a combination of factors overshadowing the benefits of the new method: high system overheads, the low cost of spawning a goal on a shared memory multiprocessor, and the increase in synchronization caused by the new methods. Directions of further research are discussed, indicating where further speedup can be attained.
Recently, Brass and Dir showed (J. Automat. Reason. 20(1) (1998) 143-165) that the well founded semantics WFS can be defined as a confluent calculus of transformation rules. This led not only to a simple extension to ...
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Recently, Brass and Dir showed (J. Automat. Reason. 20(1) (1998) 143-165) that the well founded semantics WFS can be defined as a confluent calculus of transformation rules. This led not only to a simple extension to disjunctive programs (J. logic programming 38(3) (1999) 167-213), but also to a new computation of the well-founded semantics which is linear for a broad class of programs. We take this approach as a starting point and generalize it considerably by developing a general theory of Confluent LP-systems CL. Such a system CL is a rewriting system on the set of all logic programs over a fixed signature L and it induces in a natural way a canonical semantics. Moreover, we show four important applications of this theory: (1) most of the well-known semantics are induced by confluent LP-sl sterns, (2) there are many more transformation rules that lean to confluent LP-systems, (3) semantics induced by such systems can be used to model aggregation, (4) the new systems can be used to construct interesting counterexamples to some conjectures about the space of well-behaved semantics. (C) 2001 Elsevier Science B.V. All rights reserved.
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