Sunday, November 23, 2014

 

 



Soy un nuevo usuario

Olvidé mi contraseña

Entrada usuarios

Lógica Matemáticas Astronomía y Astrofísica Física Química Ciencias de la Vida
Ciencias de la Tierra y Espacio Ciencias Agrarias Ciencias Médicas Ciencias Tecnológicas Antropología Demografía
Ciencias Económicas Geografía Historia Ciencias Jurídicas y Derecho Lingüística Pedagogía
Ciencia Política Psicología Artes y Letras Sociología Ética Filosofía
 

rss_1.0 Clasificación por Disciplina

Nomenclatura Unesco > (11) Lógica

Mostrando recursos 110,721 - 110,740 de 132,065

110721. Genetic Algorithms in Engineering and Computer Science - Edited D. Quagliarella,C. Poloni,G. Winter,John Wiley Sons
This paper deals with evolutionary processes, simulated on computers, i.e., Artificial Evolution or Evolutionary Computation (EC) [BFM97]. At least since 1994, when the first World Congress of Computational Intelligence (WCCI) [ZMR94] took place at Orlando, Florida, EC has become one out of three major domains of Computational Intelligence (CI), the other two being Neural and Fuzzy Computation. Their common peculiarity, distinguishing the CI approach toward "computer intelligence" from the classical AI approach, is the subsymbolic information processing, typical for Neural Networks (NN), Fuzzy Logic (FL), and Evolutionary Algorithms (EA). We concentrate here on just one branch of the EA, i.e., Evolution Strategies (ES) [Rec71, Sch75], born at Berlin in...

110722. A Rewrite Approach for Constraint Logic Programming - Gilles Richard
. Constraint Logic Programming (CLP ) is an extension of Logic Programming aimed at replacing the unification mechanism used in Prolog, by a more general operation called constraint satisfaction. This yields a more efficient evaluation process due to the use of appropriate algorithms designed specifically for a given constraint domain. On the other hand, it is known that pure logic programs can be represented as rewrite rules, and executed using a version of Knuth-Bendix completion procedure, called linear completion. Taking advantage of the simplification techniques available with rewriting, linear completion acts as a loopavoiding mechanism, pruning unnecessary computations when possible. A very powerful feature must also be emphasized : for...

110723. On the Compositionality and Analysis of Algebraic High-Level Nets - Johan Lilius
: This work discusses three aspects of net theory: compositionality of nets, analysis of nets and high-level nets. Net theory has often been criticised for the difficulty of giving a compositional semantics to a net. In this work we discuss this problem form a category theoretic point of view. In category theory compositionality is represented by colimits. We show how a high-level net can be mapped into a low-level net that represents its behaviour. This construction is functorial and preserves colimits, giving a compositional semantics for these high-level nets. Using this semantics we propose some proof rules for compositional reasoning with high-level nets. Linear logic is a recently discovered...

110724. Safety Property Verification of - Lalita Jategaonkar Jagadeesan,Carlos Puchol,James E. Von Olnhausen
. We present a technique for automatically verifying linear-time temporal logic safety properties of programs written in ESTEREL, a formally-defined language for programming reactive systems. In our approach, linear-time temporal logic safety properties are first translated into ESTEREL programs that model these properties. Using the ESTEREL compiler, the translations are compiled in parallel with the ESTEREL program to be verified. A trivial reachability analysis of the output of the compiler then indicates whether or not the safety property is satisfied by the program. We describe two real-world software problems --- ES- TEREL versions of two features of the AT&T5ESS R fl switching system --- and one well-known benchmark problem --- the...

110725. Reconfigurable Processor Architectures - On Hardware/software Codesign
No particular application is well-supported by a conventional microprocessor which has a predetermined set of functional units. This is particularly true in highly dynamic areas, such as multimedia, communications and other embedded systems. We suggest that additional silicon is used to provide hardware which can be dynamically configured to support any application. By combining a conventional microprocessor and FPGA reconfigurable logic on one chip, commodity pricing is maintained and yet the same part can effectively support a wide range of applications. A novel FPGA architecture is outlined which is particularly suitable for this style of implementation. Keywords : FPGA, computer architecture, parallel processing, embedded systems. Introduction Computer architecture has...

110726. Completion of Rewrite Systems with Membership Constraints Part II: Constraint Solving - Hubert Comon
this paper is to show how to solve the constraints that are involved in the deduction mechanism of the first part. This may be interesting in its own since this provides with a unification algorithm for an order-sorted logic with context variables and can be read independently of the first part. This can also be compared with unification of term schemes of various kind (Chen & Hsiang, 1991; Salzer, 1992; Comon, 1995; R. Galbav'y and M. Hermann, 1992). Indeed,

110727. Wave Pipelining YADDs - A Feasibility Study - A. Mukherjee,M. Marek-sadowska,S. I. Long
In this paper we study circuit structures obtained from direct mapping to pass transistor logic (PTL) of Yet Another Decision Diagrams (YADDs). These structures have almost equal delays along all the paths which makes wave pipelining possible. We discuss the details of a complete design, clocking and layout. In 0.5µm CMOS technology, YADDs can be clocked at a fixed rate of 715MHz for any function. Our experimental results suggest that 4 times increase of speed over standard cell design is on the average possible for the price of similar area increase. 1 Introduction We analyze circuits obtained from mapping to PTL logic of linearized, binary decision diagram (BDD) based structures which we call...

110728. Modelling and Analysis of a Steam Generator using UPPAAL - Kare J. Kristoffersen,Paul Petterson
We present the modelling and analysis of a steam generator using the automatic verification tool uppaal. The physical parts of the steam generator as well as the control software are modelled in the language of timed automata. Requirements to the system are stated in a real--time logic allowing for expessing safety properties such as 'the waterlevel in the drum must never go below nor above certain critical values'. Also the logic allows for expressing bounded liveness properties, e.g. 'steam must be produced within a certain timelimit'. The automatic modelchecker in uppaal is used to investigate system behaviour with respect to logical properties. Introduction In a steam generator water is let...

110729. Learning stage transition rules with Indlog - Rui Camacho
This paper describes the application of an Inductive Logic Programming system to Computer Assisted Aircraft Pilot Training. The usefulness of Machine Learning techniques for Computer Assisted Aircraft Pilot Training is assessed. An Inductive Logic Programming system called Indlog is presented and some preliminary results on applying it to the Computer Assisted Aircraft Pilot Training domain are reported. The problem divides into a) learning operators (previously done by Sammut and Michie) b) learning pre and post-conditions. Comprehensible pre and post-conditions were learned using a regime in which training were augmented until predictive accuracy reached 100%. Previous hand-coded pre and post-conditions were both incomplete and incorrect. 1 Introduction Inductive Logic Programming (ILP)[Mug91]...

110730. Ullrich Hustadt - Ullrich Hustadt
The most natural means for specifying a non-classical logic is by means of a Hilbert calculus. Usually, the semantics of a non-classical logic is given in terms of possible worlds. Given an axiomatization of a non-classical logics, the correspondence problem in these logics is to find for every given Hilbert axiom an equivalent property of the accessibility relation (van Benthem (1984)). For mechanizing deduction in nonclassical logics it is very important to find these correspondences Ohlbach (1991). So far the method for finding the correspondences was mostly by intuition and the verification required complex proofs van Benthem (1984). SCAN is an algorithm which offers a method for computing...

110731. Strong Modes can Change the World! - Fergus Henderson
We investigate compile-time garbage collection, structure reuse, and destructive assignment for logic programming languages, using an expressive strong mode system. By attaching groundness and uniqueness information to each node of a variable's type tree, the mode system forms the basis for carrying out these optimizations. Our system allows polymorphic mode definitions to achieve a high level of expressiveness. We implement a simple preprocessor that does structure re-use optimization for Prolog programs annotated with mode declarations. Finally, we show how our mode system can be used to provide declarative I/O for logical programming languages. Acknowledgments I'd like to thank Lee Naish (my supervisor), Harald Søndergaard, Jeff Schultz, Alistair Moffat, Will Winsborough,...

110732. A Logical View of Composition - Gordon D. Plotkin
We define two logics of safety specifications for reactive systems. The logics provide a setting for the study of composition rules. The two logics arise naturally from extant specification approaches; one of the logics is intuitionistic, while the other one is linear. iv Contents 1 Introduction 1 2 Overview 3 2.1 A calculus of sets of behaviors : : : : : : : : : : : : : : : : : : 3 2.2 A calculus of sets of processes : : : : : : : : : : : : : : : : : : 5 2.3 Testing : : : : : :...

110733. Coalgebras and Approximation - Bart Jacobs
. Motivated by a new approach in the categorical semantics of linear logic, we investigate some specific categories of coalgebras. They all arise from the canonical comonad that one has on a category of algebras. We obtain a very simple model of linear logic where linear formulas are complete lattices and intuitionistic formulas are just sets. Also, in another, domain theoretic example, we give a new characterization of continuous posets (where every elemtent is join of elements way below) as coalgebras. And finally we describe a related example where categories in which every object is coproduct of indecomposables, are coalgebras. Approximation is the key ingredient of all these coalgebras. 1...

110734. MORPH: A System Architecture for Robust High Performance Using Customization - Andrew A. Chien,Rajesh K. Gupta
Achieving 100 TeraOps performance within a tenyear horizon will require massively-parallel architectures that exploit both commodity software and hardware technology for cost efficiency. Increasing clock rates and system diameter in clock periods will make efficient management of communication and coordination increasingly critical. Configurable logic presents a unique opportunity to customize bindings, mechanisms, and policies which comprise the interaction of processing, memory, I/O and communication resources. This programming flexibility, or customizability, can provide the key to achieving robust high performance. The MultiprocessOr with Reconfigurable Parallel Hardware (MORPH) uses reconfigurable logic blocks integrated with the system core to control policies, interactions, and interconnections. This integrated configurability can improve the performance of local memory hierarchy, increase the efficiency of interprocessor coordination,...

110735. A Tableau System for Full Linear Temporal Logic - Peter H. Schmitt,Jean Goubault-larrecq
We present a sound, complete and terminating tableau system for the propositional logic of linear time with 2, 3, fl, W and U and the past operators 2 - , 3 - , flGamma , e flGamma , B and S. ffl Comments: To expand. 1 Introduction Studied in [SC85]. We adopt the notations of [MP91]. ffl Comments: To expand. 2 Linear Temporal Logic Formulas F , G, H, : : : , of linear temporal logic are built from variables A, B, C, : : : by the following grammar: F ::= A j :F j F F j F F j 2F j 3F j flF j F W F j...

110736. Improving Temporal Logic Tableaux using Integer Constraints - Reiner Hahnle,Ortrun Ibens
Introduction In this position paper we present some ideas that aim to improve analytic tableau for temporal logics with the ultimate goal of reviving the interest in using them for temporal logic satisfiability checking. Although tableau formulations for several propositional temporal logics exist [9], these are not used much in practice, because the tableau size becomes intractable already for quite small formulas. Moreover, checking tableau closure is complicated and expensive to implement. For practical purposes, usually automata theoretic approaches are preferred [3]. It might, however, still be interesting to have competitive tableau formulations as will be pointed out in Section 4. The ideas for the research reported here were stimulated...

110737. Recurrent Neural Networks to Approximate the Semantics of Acceptable Logic Programs - Yvonne Kalinke,Hans-peter Stoerr
In this paper weshow that a feedforward neural network with at least one hiddenlayer canapproximate the meaning function TP for an acceptable logic program P . This is found by using the property of acceptable logic programs that for this class of programs the meaning function TP is a contraction mapping on the complete metric space of the interpretations for P as shown by Fitting in [3]. Using this result it can be shown that for an acceptable program such a network can be extended to a recurrent neural networks that is able to approximate the iteration of the meaning function TP , that is...

110738. An Embedding of Timed Transition Systems in HOL - Rachel Cardell-oliver,Roger Hale,John Herbert
The theory of Timed Transition Systems (TTSs) developed by Henzinger, Manna and Pnueli provides a formal framework for specifying and reasoning about realtime systems. In this theory a system is described by a set of state transitions with associated time constraints. We report on work in progress to mechanize the published theory of timed transition systems using the HOL theorem prover. Different specification languages may be defined in terms of the TTS model. In particular, a real-time temporal logic (RTTL) has been used for specifying requirements and a graphical notation for specifying system designs. A semantics for each of these languages can be given in terms of TTSs,...

110739. Unknown
. 1 Introduction coordinators tile model giangi@di.unipi.it ugo@csl.sri.com A Tile-Based Coordination View of Asynchronous-calculus activity tiles coordination tiles Metodi e Strumenti per la Progettazione e la Verifica di Sistemi Eterogenei Connessi mediante Reti di Comunicazione CONFER2 COORDINA Dipartimento di Informatica, Universit`a di Pisa, Computer Science Laboratory, SRI International, Menlo Park, Tiles are rewrite rules with side effects, reminiscent of both Plotkin SOS and Meseguer rewriting logic rules. They are well suited for modeling coordination languages, since they can be composed both statically and dynamically via possibly complex synchronization and workflow mechanisms. In this paper, we give a tile-based bisimilarity semantics for the asynchronous-calculus of Honda and Tokoro and prove it equivalent to the ordinary semantics. Two kinds of tiles are...

110740. An Algebra-Based Method to Associate Rewards with EMPA Terms - Marco Bernardo
. We present a simple method to associate rewards with terms of the stochastic process algebra EMPA in order to make the specification and the computation of performance measures easier. The basic idea behind this method is to specify rewards within actions of EMPA terms, so it substantially differs from methods based on modal logic. The main motivations of this method are its ease of use as well as the possibility of defining a notion of equivalence which relates terms having the same reward, thus allowing for simplification without altering the performance index. We prove that such an equivalence is a congruence finer than the strong extended Markovian bisimulation...

 

Busque un recurso