object technology is founded on the principle that objects identified in the problem can be represented in software in the solution. Thus object design methods involve constructing an object-oriented model of the prob...
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object technology is founded on the principle that objects identified in the problem can be represented in software in the solution. Thus object design methods involve constructing an object-oriented model of the problem and mapping this model into a software design. The goal is to build in software a richer representation of the problem than is needed to meet the immediate needs, so that the software can adapt as needs change. By contrast, traditional software design techniques have taken general analysis models and transformed them into specific solutions, thereby losing the generality and making changes harder to incorporate. object designs can support the extra burden of generality because of the excellent structuring capabilities of objects. The object-oriented concepts of encapsulation and polymorphism are central to making this possible.
objectoriented databases has been developed towards the use of desktop workstations. They have designed around a client server architecture from the start. The kind of applications for which objectoriented databases...
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objectoriented databases has been developed towards the use of desktop workstations. They have designed around a client server architecture from the start. The kind of applications for which objectoriented databases have been associated also tend to suit the client-server approach. Individual objects from a compact and convenient unit which can be moved around a distributed system. Consequently, objectoriented should be considered as implementing and not replacing relational databases and used as such for applications which can usefully exploit powerful workstations configured as a client-server architecture.
The Department of Electrical Engineering at the University of Brighton has been directing research at improving manufacturing flexibility within the electronics industry, particularly within surface mount technology (...
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The Department of Electrical Engineering at the University of Brighton has been directing research at improving manufacturing flexibility within the electronics industry, particularly within surface mount technology (SMT) production. All possible tasks within the SMT manufacturing cycle were identified and documented, to provide a basis on which to apply the techniques of an object-oriented design methodology. During the design on the vision framework, classes were immediately implemented and evaluated using a software application generation environment called KAPPA. This environment allows classes to be constructed graphically, and is supported by its own 4GL programming language.
This article describes an introductory object-oriented finite element program for static and dynamic nonlinear applications. This work can be considered as an extension of the original FEM-object environment dealing w...
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This article describes an introductory object-oriented finite element program for static and dynamic nonlinear applications. This work can be considered as an extension of the original FEM-object environment dealing with linear elasticity [Elmepress Int (1993)] and nonlinearity [Comput Struct 49 (1993) 767]. Mainly the static aspects are discussed in this paper. Interested readers will find a detailed discussion of the object-oriented approach applied to finite element programming in [Proceedings IABSE colloquium on Expert Systems in Civil Engineering, Bergamo, Italy, 1989;object-oriented Finite Elem Anal Comput Struct 34 (1990) 355;Comput Struct 40 (1991) 75;Int J Numer Meth Engng 35 (1992) 425] and also in [Computer Methods in Appl Mech Engng 98 (1992);The finite element method, 1987] and references therein. Our ambition, in this paper, is limited to a presentation of an introductory object-oriented finite element package for nonlinear analysis. Our goal is to make a starting package available to newcomers to the object-oriented approach and to provide an answer to the large number of demands for such a program received in recent time. In the first part of the paper, a brief recall of the basics of finite element modeling applied to continuum mechanics is given. Von Mises plasticity including isotropic and kinematic hardening, which is used as model problem, is described. This first part also presents an over-view of the main features of the object-oriented approach. In the second part of this paper, classes and associated tasks forming the kernel of the code are described in detail. A hierarchy of classes is proposed and discussed;it provides an immediate overview of the program's capabilities. Finally interactions between classes are explained and numerical examples illustrate the approach. (C) 2001 Elsevier Science Ltd. All rights reserved.
Model-based objectoriented Systems Engineering (MOOSE) is a full lifecycle computer systems engineering method intended for the development of products that make use of application specific embedded and distributed c...
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Model-based objectoriented Systems Engineering (MOOSE) is a full lifecycle computer systems engineering method intended for the development of products that make use of application specific embedded and distributed computer systems. The method is divided into a number of phases that effect a series of transformations leading to an implementation, and it is supported by a Product Engineers workbench that supports the capture, translation and execution of the model.
Prior research has shown that high levels of software reuse can be achieved through the use of object-oriented frameworks. An object-oriented framework captures the common aspects of a family of applications, thus all...
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Prior research has shown that high levels of software reuse can be achieved through the use of object-oriented frameworks. An object-oriented framework captures the common aspects of a family of applications, thus allowing the designers and implementers to reuse this experience at the design and code levels. In spite of being a powerful design solution, frameworks are not always easy to use. A technique is described that uses domain specific languages (DSL) to describe the framework variation points and therefore syntactically assure the creation of valid framework instances. This approach allows framework users to develop applications without the worry of framework implementation, so allowing them to remain focused on the problem domain. In addition, the use of DSLs allows for better error handling, when compared to the standard approach of adapting frameworks by directly adding subclasses. The DSL programs are translated to the framework instantiation code using a transformational system. The approach is illustrated through two real-world frameworks.
The specification of system requirements can be construed as a set of tests which the design and subsequent implementation are expected to satisfy. Our approach is to adopt an architectural design methodology in which...
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The specification of system requirements can be construed as a set of tests which the design and subsequent implementation are expected to satisfy. Our approach is to adopt an architectural design methodology in which distributed systems are described, modelled and constructed in terms of their software structure. Descriptions of the constituent software components and their interconnection patterns provide a clear and concise level at which to specify, design and analyse systems, and can be used directly by construction tools to generate the system itself. The Architect's Assistant is intended to provide an environment for supporting this methodology.
Experiences on the development of an advanced control system using the object-orientedprogramming (OOP) language Smalltalk-80 revealed that the language has many powerful features for rapid prototyping and simulating...
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Experiences on the development of an advanced control system using the object-orientedprogramming (OOP) language Smalltalk-80 revealed that the language has many powerful features for rapid prototyping and simulating advanced control systems, especially those involving intelligent features. In the development of an intelligent system identification supervisor (ISIS), Smalltalk-80 proved very suitable for incorporation into control-oriented simulation languages. Smalltalk 80's advantage lies in its portability, productivity, user interface and language. An overview of the development of ISIS is presented and the disadvantages of the language are described.
Many long-running applications would greatly benefit from being able to recover faulty versions in N-version programs since their exclusion from further use undermines the availability of the system. Developing a reco...
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Many long-running applications would greatly benefit from being able to recover faulty versions in N-version programs since their exclusion from further use undermines the availability of the system. Developing a recovery feature, however, is a very complex and error-prone task, which the author believes has not received adequate attention. Although many researchers are aware of the importance of version recovery, there are very few schemes which include these features. Even when they do, they rely on ad hoc programming and are not suitable for object-oriented systems. The author believes that developing systematic approaches here is crucial, and formulates a general approach to version recovery in class diversity schemes, which is based on the concept of the abstract version state. The approach extends the recently-developed class diversity scheme and relies on important ideas motivated by community error recovery. The diversity scheme includes two-level error detection which allows error latency to be controlled. To use it, special application-specific methods for each version object have to be designed, which would map the internal state into the abstract state and, at the same time, form a basis for one-level version recovery. The approach is discussed in detail, compared with the existing solutions, and additional benefits of using the abstract version state are shown. The intention is to outline a disciplined way for providing version recovery and thus make it more practical. Two promising approaches which can be used for developing new structuring techniques incorporating the abstract version state concept are discussed.
In this paper the burning issue of the migration of legacy systems to object technology is examined and the major elements of an evolving pattern language, ADAPTOR (Architecture-Driven And Pattern-based Techniques for...
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In this paper the burning issue of the migration of legacy systems to object technology is examined and the major elements of an evolving pattern language, ADAPTOR (Architecture-Driven And Pattern-based Techniques for object Re-engineering) to illustrate an approach currently being investigated by the author. ADAPTOR can be considered to be one of a set of interlinked pattern languages that address the wider issues of software architecture. It is given primacy here because of its relative maturity, having been tested in a number of live projects in the telecommunications industry.
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