We present a method of representing some classes of default theories as normal logic programs. The main point is that the standart semantics (i.e., SLDNF-resolution) computes answer substitutions that correspond exact...
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We present a method of representing some classes of default theories as normal logic programs. The main point is that the standart semantics (i.e., SLDNF-resolution) computes answer substitutions that correspond exactly to the extensions of the represented default theory. This means that we give a correct implementation of default logic. We explain the steps of constructing a logic program LogProg(P,D) from a given default theory (P,D), give some examples, and derive soundness and completeness results.
This paper describes the design and a prototypical implementation of COMPLEX, a logic-based system extended with concepts from the object-oriented paradigm, intended as a tool for the development of knowledge-based ap...
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This paper describes the design and a prototypical implementation of COMPLEX, a logic-based system extended with concepts from the object-oriented paradigm, intended as a tool for the development of knowledge-based applications. The system supports a logic language, called Complex-Datalog (C-Datalog), enhanced by semantic constructs to provide facility for data abstraction. Its implementation is based on a bottom-up computational model that guarantees a fully declarative style of programming. However, the user is also given the possibility of running a query using a top-down model of computation. Efficiency of execution is the result of the integration of different novel technologies for the compilation and the execution of queries.
This paper presents a: constraint logic programming model for the traveling salesman problem with time windows which yields an exact branch-and-bound optimization algorithm without any restrictive assumption on, the t...
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This paper presents a: constraint logic programming model for the traveling salesman problem with time windows which yields an exact branch-and-bound optimization algorithm without any restrictive assumption on, the time windows. Unlike dynamic programming approaches whose performance relies heavily on the degree of discretization applied to the data, our algorithm does not suffer from such space-complexity issues. The data-driven mechanism at its core more fully exploits pruning rules developed in operations research by using them not only a priori but also dynamically during the search. Computational results are reported and comparisons are made with both exact and heuristic algorithms. On Solomon's well-known test bed, our algorithm is instrumental in achieving new best solutions for some of the problems in set RC2 and strengthens the presumption of optimality for the best known solutions to the problems in set C2.
A flexible manufacturing system (FMS) is a complex mechanical system capable of fabrication, machining, and assembly operations. It may be integrated with material-handling equipment and an automated storage system. A...
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A flexible manufacturing system (FMS) is a complex mechanical system capable of fabrication, machining, and assembly operations. It may be integrated with material-handling equipment and an automated storage system. An FMS is information intensive and links computer-aided design systems to numerically controlled machines, robots, and other types of equipment, all supervised by a complicated control system. In order to design, control, and understand the operation of such a system, a modeling tool with expressive power and the ability to analyze and represent the static and dynamic nature of the system is desired. Currently, modeling tools belong either to Petri net, to queuing network models, or to simulation languages. This paper presents a new approach toward the modeling and analysis of an FMS focusing on shop-floor control processes. This approach is based on concurrent logic programming, which uses the theoretical foundation of Communicating Sequential Processes, and Guarded commands with nondeterminacy. The modeling approach is implemented using Flat Concurrent Prolong (FCP) on a Sun workstation or on a VAX machine.
Concolic testing is a well-known validation technique for imperative and object oriented programs. In a previous paper, we have introduced an adaptation of this technique to logic programming. At the heart of our fram...
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Concolic testing is a well-known validation technique for imperative and object oriented programs. In a previous paper, we have introduced an adaptation of this technique to logic programming. At the heart of our framework lies a specific procedure that we call "selective unification". It is used to generate appropriate run-time goals by considering all possible ways an atom can unify with the heads of some program clauses. In this paper, we show that the existing algorithm for selective unification is not complete in the presence of non-linear atoms. We then prove soundness and completeness for a restricted version of the problem where some atoms are required to be linear. We also consider concolic testing in the context of constraint logic programming and extend the notion of selective unification accordingly.
作者：
Apt, KRUNIV AMSTERDAM
DEPT MATH COMP SCI PHYS & ASTRON 1018 TV AMSTERDAM NETHERLANDS
We claim that programming within the logic programming paradigm suffers from lack of attention given to iteration and arrays. To convince the reader about their merits we present several examples of logic and constrai...
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We claim that programming within the logic programming paradigm suffers from lack of attention given to iteration and arrays. To convince the reader about their merits we present several examples of logic and constraint logic programs which use iteration and arrays instead of explicit recursion and lists. These programs are substantially simpler than their counterparts written in the conventional way. They are easier to write and to understand, are guaranteed to terminate and their declarative character makes it simpler to argue about their correctness. Iteration is implemented by means of bounded quantification.
In order to enable logic programming to deal with the diversity of pervasive systems, where many heterogeneous, domain-specific computational models could benefit from the power of symbolic computation, we explore the...
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In order to enable logic programming to deal with the diversity of pervasive systems, where many heterogeneous, domain-specific computational models could benefit from the power of symbolic computation, we explore the expressive power of labelled systems. To this end, we define a new notion of truth for logic programs extended with labelled variables interpreted in non-Herbrand domains-where, however, terms maintain their usual Herbrand interpretations. First, a model for labelled variables in logic programming is defined. Then, the fixpoint and the operational semantics are presented and their equivalence is formally proved. A meta-interpreter implementing the operational semantics is also introduced, followed by some case studies aimed at showing the effectiveness of our approach in selected scenarios.
This paper presents a partial deduction method in disjunctive logic programming. Partial deduction in normal logic programs is based on unfolding between normal clauses, hence it is not applicable to disjunctive logic...
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This paper presents a partial deduction method in disjunctive logic programming. Partial deduction in normal logic programs is based on unfolding between normal clauses, hence it is not applicable to disjunctive logic programs in general. Then we introduce a new partial deduction technique, called disjunctive partial deduction, which preserves the minimal model semantics of positive disjunctive programs and the stable model semantics of normal disjunctive programs. From the procedural side, disjunctive partial deduction is combined with a bottom-up proof procedure of disjunctive logic programs, and top-down partial deduction is introduced for query optimization. Disjunctive partial deduction is also applied to optimizing abductive logic programs and compiling propositional disjunctive programs. (C) Elsevier Science Inc., 1997.
Situatedness is a fundamental requirement for today's complex software systems, as well as for the computational models and programming languages used to build them. Spatial and temporal situatedness, in particula...
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We present a novel application of Inductive logic programming (ILP) to the problem of diterpene structure elucidation from C-13 NMR spectra. Diterpenes ale organic compounds of low molecular weight with a skeleton of ...
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We present a novel application of Inductive logic programming (ILP) to the problem of diterpene structure elucidation from C-13 NMR spectra. Diterpenes ale organic compounds of low molecular weight with a skeleton of 20 caibon atoms. They are of significant chemical and commercial interest because of their use as lead compounds in the search for new pharmaceutical effectors. The interpretation of diterpene C-13 NMR spectra normally requires specialists with detailed spectroscopic knowledge and substantial experience in natural products chemistry, specifically knowledge on peak patterns and chemical structures. Given a database of peak patterns for diterpenes with known structure, we apply several ILP approaches to discover correlations between peak patterns and chemical structure. The approaches used include first-order inductive learning, relational instance based learning, induction of logical decision trees, and inductive constraint logic. Performance close to that of domain experts is achieved, which suffices for practical use.
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