http://biblioteca.universia.net/vernivel.do?start=360&nivel=11 Mostrando recursos 361 - 380 de 88,632 es http://biblioteca.universia.net/img/logotipo.jpg http://biblioteca.universia.net/ http://biblioteca.universia.net/ficha.do?id=41913714 We define a new syntactic class of logic programs, omega-restricted programs. We divide the predicate symbols of a logic program into two parts: domain and non-domain predicates, where the domain predicates are defined by the maximal stratifiable subset of the rules of the program. We extend the usual de nition of stratification by adding a special omega-stratum that holds all unstratifiable predicates of the program. We demand that all variables that occur in a rule also occur in the rule bo... http://biblioteca.universia.net/ficha.do?id=41939740 With the advent of deep sub-micron technologies, interconnect loads and delays are becoming dominant. Consequently, the currently used design flow of iteratively performing logic synthesis with statistical wire-load models, doing placement & routing, extracting parasitics, and using them back in the synthesis tool runs into serious timing convergence problems. Layout-driven synthesis has become the need of the day. A number of researchers have addressed the problem of timing convergence and p... http://biblioteca.universia.net/ficha.do?id=41565819 st order logic can still be adequate programming languages. Mathematicians have used first order logic as a programming language in which to encode all the known acceptable principles of mathematical inference. The result is axiomatic set theory. Any mathematical proof can, in principle, be expressed as a proof in first order set theory. In this sense axiomatic set theory is an adequate foundation for mathematics. However, it is known that these principles of inference are not complete, e.g.,... http://biblioteca.universia.net/ficha.do?id=38344728 O método de combinação de Nelson-Oppen permite que vários procedimentos de decisão, cada um projetado para uma teoria especíamp;#64257;ca, possam ser combinados para inferir sobre teorias mais abrangentes, através do princípio de propagação de igualdades. Provadores de teorema baseados neste modelo são beneamp;#64257;ciados por sua característica modular e podem evoluir mais facilmente, incrementalmente. Diamp;#64256;erence logic é uma subteoria da aritmética linear. Ela é formada por constra... Diego Caminha Barbosa de Oliveira http://biblioteca.universia.net/ficha.do?id=41559098 this paper we describe TLA from a logical perspective; our description of TLA has three aspects: 1. As a logic, TLA has a precise syntax and semantics. We define these in the next section. Our intent is not to develop a new TLA, but rather to explain and to refine Lamport's definition of TLA [19]. 2. Like HOL [13] and other logics, TLA can serve for representing reactive systems in several styles. In particular, a specification may describe concurrent steps as interleaved or simultaneous; com... http://biblioteca.universia.net/ficha.do?id=41845914 this paper, however, that the techniques of nonmonotonic logic may provide a better theoretical framework---at least for the formalization of commonsense normative reasoning---than the usual modal treatment. After reviewing some standard approaches to deontic logic, I focus on two areas in which nonmonotonic techniques promise improved understanding: reasoning in the presence of conflicting obligations, and reasoning with conditional obligations. John F. Horty http://biblioteca.universia.net/ficha.do?id=45798600 Abstract. Rewriting logic can be used to prototype systems for automated deduction. In this paper, we illustrate how this approach allows experiments with deduction strategies in a flexible and conceptually satisfying way. This is achieved by exploiting the reflective property of rewriting logic. By specifying a theorem prover in this way one quickly obtains a readable, reliable and reasonably efficient system which can be used both as a platform for tactic experiments and as a basis for an o... Bjarne Holen; Einar Broch Johnsen; Arild Waaler http://biblioteca.universia.net/ficha.do?id=45907728 Abstract. Rewriting logic can be used to prototype systems for automated deduction. In this paper, we illustrate how this approach allows experiments with deduction strategies in a flexible and conceptually satisfying way. This is achieved by exploiting the reflective property of rewriting logic. By specifying a theorem prover in this way one quickly obtains a readable, reliable and reasonably efficient system which can be used both as a platform for tactic experiments and as a basis for an o... Bjarne Holen; Einar Broch Johnsen; Arild Waaler http://biblioteca.universia.net/ficha.do?id=45663473 In this paper we present a strongly normalising cut-elimination procedure for classical logic. This procedure adapts Gentzen's standard cut-reductions, but is less restrictive than previous strongly normalising cut-elimination procedures. In comparison, for example, with works by Dragalin and Danos et al., our procedure requires no special annotations on formulae and allows cut-rules to pass over other cut-rules. In order to adapt the notion of symmetric reducibility candidates for provi... C. Urban; Marseille France; G. M. Bierman http://biblioteca.universia.net/ficha.do?id=41748840 Formulas of Hoare logic are asserted programs # # # where # is a program and #, # are assertions. The language of programs varies; in the survey [Apt 1980], one finds the language of while programs and various extensions of it. But the assertions are traditionally expressed in first-order logic (or extensions of it). In that sense, first-order logic is the underlying logic of Hoare logic. We question the tradition and demonstrate, on the simple example of while programs, that alternative asse... Yuri Gurevich,Andreas Blass http://biblioteca.universia.net/ficha.do?id=20846768 A weakly complete finitary axiomatization for EQPL (exogenous quantum propositional logic) is presented. The proof is carried out using a non trivial extension of the Fagin-Halpern-Megiddo technique together with three Henkin style completions. Mateus, P.; Sernadas, A. http://biblioteca.universia.net/ficha.do?id=45988311 Abstract. van Gelder's alternating fixpoint theory has proven to be a very useful tool for unifying and characterizing various semantics for logic programs without priority. In this paper we propose an extension of van Gelder's alternating fixpoint theory and show that it can be used as a general semantic framework for logic programs with priority. Specifically, we define three declarative and model-theoretic semantics in this framework for prioritied logic programs: prioritized ans... Kewen Wang; Lizhu Zhou; Fangzhen Lin http://biblioteca.universia.net/ficha.do?id=46515969 Defeasible logic is a non-monotonic logic with applications in rule-based domains such as law. To ease the development and improve the accuracy of expert systems based on defeasible logic, it is desirable to automatically induce a theory of the logic from a training set of precedent data. Empirical evidence suggests that minimal theories that describe the training set tend to be more faithful representations of reality. We show via transformation from the hitting set problem that this global ... Databases Benjamin Johnston; Benjamin Johnston; Guido Governatori http://biblioteca.universia.net/ficha.do?id=46631884 The Logic Push-Down Automaton (LPDA) is introduced as an abstract operational model for the evaluation of logic programs. The LPDA can be used to describe a significant number of evaluation strategies, ranging from the top-down OLD strategy to bottom-up strategies, with or without prediction. Two types of dynamic programming, i.e. tabular, interpretation are defined, one being more efficient but restricted to a subclass of LPDAs. We propose to evaluate a logic program by first compiling it in... Eric Villemonte De La Clergerie; Bernard Lang http://biblioteca.universia.net/ficha.do?id=46918991 New topics, most notably the World Wide Web, have put considerable pressure on the Computer Science curriculum. Computing Curricula 2001represents a consensus that topics in the core must be reduced to accommodate new topics as they emerge. Unfortunately, digital logic has been reduced to 1/3 its original coverage. We argue that more core coverage should be given to digital logic, and that it should be included in Computer Architecture, not Discrete Systems. Digital logic is fundamental th... Mark Hoffman Department; Mark E. Hoffman http://biblioteca.universia.net/ficha.do?id=47086947 Over recent years, various semantics have been proposed for dealing with updates in the setting of logic programs. The availability of di#erent semantics naturally raises the question of which are most adequate to model updates. A systematic approach to face this question is to identify general principles against which such semantics could be evaluated. In this paper we motivate and introduce a new such principle -- the refined extension principle. Such principle is complied with by the stabl... Jose Julio Alferes; Federico Banti; Antonio Brogi; Joao Alexandre Leite http://biblioteca.universia.net/ficha.do?id=47110368 Possibilistic Defeasible Logic Programming (P-DeLP) is a logic programming language which combines features from argumentation theory and logic programming, incorporating as well the treatment of possibilistic uncertainty and fuzzy knowledge at object-language level. Defeasible argumentation in general and P-DeLP in particular provide a way of modelling non-monotonic inference. From a logical viewpoint, capturing defeasible inference relationships for modelling argument and warrant is p... Carlos Chesñevar; Guillermo Simari; Lluís Godo; Teresa Alsinet http://biblioteca.universia.net/ficha.do?id=45729937 Abstract. Possibilistic logic and quasi-classical logic are two logics that were developed in artificial intelligence for coping with inconsistency in different ways, yet preserving the main features of classical logic. This paper presents a new logic, called quasi-possibilistic logic, that encompasses possibilistic logic and quasi-classical logic, and preserves the merits of both logics. Indeed, it can handle plain conflicts taking place at the same level of certainty (as in quasi-classical ... Didier Dubois; Sébastien Konieczny; Henri Prade http://biblioteca.universia.net/ficha.do?id=45842996 tance and encouragement. The elevator control program described in this journal by Dyck and Caines [2] can be implemented more concisely in d-Prolog, a defeasible logic program-ming system developed by Nute [3, 4, 5]. In defeasible logic, more specific rules take precedence over more general ones. Thus, the d-Prolog program-mer can state general rules and then give explicit exceptions, just as humans do when explaining complex regularities to each other. Michael A. Covington http://biblioteca.universia.net/ficha.do?id=47945576 ABSTRACT: Intelligent systems have appeared in many technical areas, such as consumer electronics, robotics and industrial control systems. Many of these intelligent systems are based on fuzzy control strategies which describe complex systems mathematical model in terms of linguistic rules. Since the 1980s new techniques have appeared from which fuzzy logic been applied extensively in medical systems. This paper surveys the utilisation of fuzzy logic control and monitoring in medical sciences. D. A. Linkens; M. F. Abbod; M. Mahfouf