Withthe increased interest in workstation networks for parallel and high performance computing it is necessary to reexamine the use of process migration algorithms, to improve the overall utilization of the system, t...
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One of most serious problems plaguing the World Wide Web today is that of broken hypertext links, which are a major annoyance to browsing users and also a cause of tarnished reputation and possible loss of opportunity...
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One of most serious problems plaguing the World Wide Web today is that of broken hypertext links, which are a major annoyance to browsing users and also a cause of tarnished reputation and possible loss of opportunity for information providers. the root of the problem lies in the current Web architecture's lack of support for referential integrity. this paper presents a model for the provision of referential integrity for Web resources which supports resource migration and tolerates site and communication failures. the approach is object-oriented, highly flexible, completely distributed, and does not require any global administration. An attractive feature of our design is the provision of a lightweight mechanism which provides referential integrity, and which may be customised on a per resource basis to provide increased fault-tolerance and performance. Our system follows an evolutionary approach, supporting parallel operation withthe existing Web, allowing users to gain the additional benefits of referential integrity while allowing continued access through trusted software components.
Today, Signalling engineers must no longer merely program, but also specify, validate and implement, to attain the end goal of a proven fault-free system. Withthe revolution in microprocessing power, designers of cri...
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ISBN:
(纸本)1853124079
Today, Signalling engineers must no longer merely program, but also specify, validate and implement, to attain the end goal of a proven fault-free system. Withthe revolution in microprocessing power, designers of critical real time systems have experienced a gradual evolution in this field. Most of these designers have been forced to abandon their traditional way of thinking, a product of their electronics engineering culture, and to take on the culture of software engineers, who first believed they would come up with ''miracle'' tools and languages. the problem, of course, is that the programming languages proposed were not appropriate to the needs of signalling engineers. Tn particular, the sequential concept was not appropriate for the parallel structure intrinsic to the problems in question. Synchronous Data Flow languages could provide a satisfactory solution for designers of critical real time signalling systems. the data flow model is, in fact, directly based on a description in the form of block diagrams preferred by automation engineers. Moreover, the synchronous model perfectly matches the execution mode of the systems described in terms of input sampling, calculation, output transmission and return in an infinite loop.
the proceedings contain 42 papers. the special focus in this conference is on systemstheory and Design Environments and Tools. the topics include: On the structure of discrete systems;identification and recognition t...
ISBN:
(纸本)9783540607489
the proceedings contain 42 papers. the special focus in this conference is on systemstheory and Design Environments and Tools. the topics include: On the structure of discrete systems;identification and recognition through shape in complex systems;a logical approach to system construction;task management system;toward a unified theory of discrete event systems;general systems description and implications;proving system properties by means of trigger-graph and petri nets;refinement mapping for general (discrete event) systemstheory;a system-theoretic approach to planning and programming;equality of functions in CAST;basins of attraction estimation through symbolic graphical computing techniques;temporal and functional verification of a symbolic representation of complex systems;modelling differential equations by basic information technology means;system theoretic aspects of software architectures;a language for describing complex-evolutive softwaresystems;an architecture for process modeling and execution support;a formal semantics for a graphical model representation in system design;a user-interface for a microsystems high-level simulator;CAST extensions to DASME to support generalized information theory;symbolic computing aided design of nonlinear PID controllers;discrete event simulation in an environment for temporal expert systems;TOMSPIN - a tool for modeling with stochastic petri nets;hybrid evolutionary programming;automatic induction of DEVS structures;systemsengineering and infrastructures for open computer based systems;object-oriented high level modeling of complex systems;multifacetted, object oriented modeling in the transportation domain;a tool environment for the design of complex, real-time systems;systems level specification and modelling of reactive systems and control through deliberative and reactive planning.
In recent years, a number of Dutch companies have used the algebraic specification formalism Asf+Sdf. Bank MeesPierson has specified a language for describing interest rate products, their translation into COBOL, and ...
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the proceedings contain 60 papers. the special focus in this conference is on Algebraic Methodology and software Technology. the topics include: Two industrial trials of formal specification;industrial applications of...
ISBN:
(纸本)9783540614630
the proceedings contain 60 papers. the special focus in this conference is on Algebraic Methodology and software Technology. the topics include: Two industrial trials of formal specification;industrial applications of ASF + SDF;the embedded software of an electricity meter: an experience in using formal methods in an industrial project;applying research results in the industrial environment;using heterogeneous formal methods in distributed softwareengineering education;introducing formal methods to software engineers through OMG’s corba environment and interface definition language;toward a classification approach to design;semantic foundations for embedding HOL in nuprl;free variable tableaux for a many sorted logic with preorders;automating induction over mutually recursive functions;pushouts of order-sorted algebraic specifications;a formal framework for modules with state;object-oriented implementation of abstract data type specifications;on the completeness of the equations for the kleene star in bisimulation;an equational axiomatization of observation congruence for prefix iteration;finite axiom systems for testing preorder and de simone process languages;constructive semantics of esterel;using ghost variables to prove refinement;tracing the origins of verification conditions;preprocessing for lnvariant validation;formal verification of SIGNAL programs;the discrete time TOOLBUS;a study on the specification and verification of performance properties;symbolic bisimulation for limed processes;approximative analysis by process algebra with graded spatial actions;boolean formalism and explanations;proving existential termination of normal logic programs;programming in lygon and some characteristics of strong innermost normalization.
Complexity metrics, such as McCabe's cyclomatic number of a program control graph and Halstead's number of operator/operand occurrences have been used extensively to measure the structural complexity of proced...
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Complexity metrics, such as McCabe's cyclomatic number of a program control graph and Halstead's number of operator/operand occurrences have been used extensively to measure the structural complexity of procedural programs. However, few suitable complexity metrics have been developed for rule-based programs written in OPS5 and OPS5-like rule-based languages. Withthe increasingly common use of rule-based languages in knowledge-based systems, this paper describes new complexity metrics to more accurately measure the complexity of OPS5 rule-based programs. the practicality of these metrics is empirically demonstrated by applying them to measure the complexity of a suite of benchmark OPS5 expert systems.
there are almost universal complaints that too much research effort goes wasted and never finds application in the industrial world. the complaints are raised symmetrically both by the academia and by the industrial w...
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We propose two new constructs for object oriented programming that significantly increase polymorphism. Consequently, code may be reused in ways unaccounted for by existing machinery. these constructs of type correspo...
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