We discuss problems to construct intelligent decision support systems, and propose KORE (Knowledge Oriented Reasoning Environment) as an environment for developing such systems. KORE is a hybrid tool for assisting uni...
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Revision programming is a formalism to describe and enforce updates of belief sets and databases. that formalism was extended by Fitting who assigned annotations to revision atoms. Annotations provide a way to quantif...
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Revision programming is a formalism to describe and enforce updates of belief sets and databases. that formalism was extended by Fitting who assigned annotations to revision atoms. Annotations provide a way to quantify the confidence (probability) that a revision atom holds. the main goal of our paper is to reexamine the work of Fitting, argue that his semantics does not always provide results consistent with intuition, and to propose an alternative treatment of annotated revision programs. Our approach differs from that proposed by Fitting in two key aspects: we change the notion of a model of a program and we change the notion of a justified revision. We show that under this new approach fundamental properties of justified revisions of standard revision programs extend to the annotated case. (C) 2002 Elsevier Science B.V. All rights reserved.
A goal-directed logicprogramming system is presented, and an experimental implementation is described. It differs from other logicprogramming languages in that a goal that has just failed has certain of its variable...
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A goal-directed logicprogramming system is presented, and an experimental implementation is described. It differs from other logicprogramming languages in that a goal that has just failed has certain of its variables unbound and is immediately re-evaluated. this control mechanism gives priority to the failed goal until it either succeeds or fails for good. the modifications required are considerable, since they require freeing the control structure of logicprogramming from its emphasis on backtracking and on the order of unbinding and rebinding variables that it entails. the backtrack mechanisms normal to logicprogramming lack goal direction and are therefore not part of the system. Examples are given to show the advantages of the system presented over other approaches to logicprogramming.
Refinery complex production process usually involves some distinct or implied production rules and expert experiences. Representation and utilizing these heuristic rules is conducive to efficient scheduling optimizati...
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Refinery complex production process usually involves some distinct or implied production rules and expert experiences. Representation and utilizing these heuristic rules is conducive to efficient scheduling optimization. In this paper, the heuristic rules were formulated using disjunctive form and logical proposition, and a discrete-time based multi-periodic generalized disjunctive programming (GDP) scheduling model was built. Due to the combining of logic expressions and algebra expressions, heuristic rules were utilized by the proposed model, while scheduling optimization was ensured. the formulated model was used to deal with a refinery scheduling problem. Case study shows the model's feasibility and efficiency.
this paper considers open logic programs originally introduced as a tool to build an OR-compositional semantics of logic programs. We extend the original semantic definitions in the framework of the general approach t...
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this paper considers open logic programs originally introduced as a tool to build an OR-compositional semantics of logic programs. We extend the original semantic definitions in the framework of the general approach to the semantics of logic programs described by Gabbrielli and Levi (1991). We first define an operational semantics O-Omega(P) which models computed answer substitutions and which is compositional w.r.t. the union of programs. Next, we consider the semantic domain of Omega-denotations, which are sets of clauses with a suitable equivalence relation. the fixpoint semantics F-Omega(P) given by Bossi and Menegus (1991) is proved equivalent to the operational semantics. From the model-theoretic viewpoint, an Omega-denotation is mapped onto a set of Herbrand interpretations, thus leading to a definition of an Omega-model based on the classical notion of truth. Moreover, we consider a particular kind of Omega-models (compositional models), and we show that O-Omega,(P) is a (nonminimal) compositional Omega-model. A suitable abstraction of O-Omega,(P) is compositional and fully abstract w.r.t. the equivalence induced by successful derivations. Finally, some applications of our semantics are discussed. In particular, O-Omega,(P) can be viewed as the foundation of modular program analysis.
the main aim of the paper is to construct a logical system in which properties of programs can be formalized for verification, synthesis and transformation. the paper has two main points. One point is a realizability ...
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the main aim of the paper is to construct a logical system in which properties of programs can be formalized for verification, synthesis and transformation. the paper has two main points. One point is a realizability interpretation of coinductive definitions of predicates. the other point is extraction of programs which treat streams. An untyped predicative theory TIDv is presented, which has the facility of coinductive definitions of predicates and is based on constructive logic. Properties defined by the greatest fixed point, such as streams and the extensional equality of streams, can be formalized by the facility of coinductive definitions of predicates in TIDv. A q-realizability interpretation for TIDv is defined and the soundness of the interpretation is proved. By the realizability interpretation, a program which treats streams can be extracted from a proof of its specification in TIDv. A general program extraction theorem and a stream program extraction theorem are presented.
logicprogramming has been widely used because of the clearness of its semantics and its extensibility. Many inference systems have been proposed using a logicprogramming framework. But few of these have studied logi...
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We show how a class of domains written in the Language E, a high level language for reasoning about actions, narratives and. change, can be translated into the argumentation framework of logicprogramming without Nega...
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ISBN:
(纸本)3540667490
We show how a class of domains written in the Language E, a high level language for reasoning about actions, narratives and. change, can be translated into the argumentation framework of logicprogramming without Negation as Failure (LPwNF). this translation enables us 1) to understand default persistence as captured by various temporal reasoning frameworks in a simple and natural way, by assigning higher priority to information about effects of later actions over effects of earlier actions;2) to develop an argumentation-based computational model for this type of reasoning in logicprogramming goal-driven style.
In general, the set of stable models of a recursive propositional logic program can be quite complex. For example, it follows from results of Marek, Nerode, and Remmel [8] that there exists finite predicate logic prog...
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ISBN:
(纸本)3540667490
In general, the set of stable models of a recursive propositional logic program can be quite complex. For example, it follows from results of Marek, Nerode, and Remmel [8] that there exists finite predicate logic programs and recursive propositional logic programs which have stable models but no hyperarithmetic stable models. In this paper, we shall define several conditions which ensure that recursive logic program has astable model which is recursive.
Object-oriented programming has been widely adopted as a powerful programming paradigm, enabling software engineers to design systems using structures which map naturally onto the problem domain. Using ideas from logi...
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ISBN:
(纸本)0780336461
Object-oriented programming has been widely adopted as a powerful programming paradigm, enabling software engineers to design systems using structures which map naturally onto the problem domain. Using ideas from logicprogramming, a class definition can be treated as a logictheory, making it amenable to formal reasoning. Each class corresponds to a set of objects in the problem domain. We extend this idea, so that an object may have a degree of membership in more than one class, i.e. each class represents a fuzzy set of objects in the problem domain. Uncertainty is also allowed in data values and computational methods associated with objects. the problem of multiple inheritance is addressed by including methods for resolving conflict in class definitions. A system is being implemented in Fril, to allow development of fuzzy object oriented knowledge-based applications. this system is known as Fril++. the ideas are also applicable to other logicprogramming systems, assuming a method can be programmed at the object or meta-level to deal with uncertainty in terms, relations, and inference.
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