This paper presents a mechanism for automatically generating new classes from classes existing in a library by using their modification histories. To generate classes that are likely to meet programmer's requireme...
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This paper presents a mechanism for automatically generating new classes from classes existing in a library by using their modification histories. To generate classes that are likely to meet programmer's requirements and that are consistent with the existing classes, we propose three actors, a Specifier, a Finder, and an Integrator. The Specifier records the history of modifications between methods with the same interface of a parent class and its heir. If the required method is not defined in the existing class which a programmer is referring to, the Finder retrieves classes similar to the referenced class and the Integrator applies the past modifications of similar classes to the referenced class. Classes are determined to be similar based on their positions in a class hierarchy tree. Both the Specifier and Integrator are achieved by using a method integration algorithm based on object-oriented bounded program slicing and class dependence graph matching. This mechanism enables programmers to reuse classes with little or no modification and, thus, easily create object-oriented programs.
The association of object-oriented programming and symbolic computation techniques introduces certain changes in finite element code organization. The purpose of this approach is to speed up the design of new formulat...
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The association of object-oriented programming and symbolic computation techniques introduces certain changes in finite element code organization. The purpose of this approach is to speed up the design of new formulations. Previous papers have described the basic concepts of the method. In this paper, the focus is placed on functional aspects of symbolic tools for the development of finite element formulations. Two practical examples are used to illustrate this point. The first is a space-time formulation for an incompressible flow driven by the Navier-Stokes equations, and the second is a finite element derivation of the total potential energy for linear elasticity. (C) 2000 Elsevier Science B.V. All rights reserved.
The paper presents an overview of various modeling paradigms applicable to the analysis of complex decisionmaking problems that can be represented by large non-linear models. Such paradigms are illustrated by their ap...
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The paper presents an overview of various modeling paradigms applicable to the analysis of complex decisionmaking problems that can be represented by large non-linear models. Such paradigms are illustrated by their application to the analysis of a model that helps to identify and analyze various cost-effective policy options aimed at improving European air quality. Also presented is the application of this model to support intergovernmental negotiations. (C) 2000 Elsevier Science B.V. All rights reserved.
Artificial intelligence can play an important role in the reduction of manufacturing costs and the enhancement of production efficiency and product quality. In order to assist designers in the early stages of a produc...
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Artificial intelligence can play an important role in the reduction of manufacturing costs and the enhancement of production efficiency and product quality. In order to assist designers in the early stages of a product development this paper develops an intelligent methodology for integration of design and assembly planning processes, including product design, assembly evaluation and redesign, assembly process planning, design of assembly system and assembly simulation, subjected to both econo-technical and ergonomic evaluations. A new unified class of object-oriented knowledge based Petri nets called OOKPNs;incorporating knowledge based expert systems and fuzzy logic into ordinary place-transition Petri nets, is defined and used for the representation and modeling of the distributed design processes. A prototype intelligent integrated design and assembly planning system (IIDAP) is implemented through distributed blackboard structure with concurrent integration of multiple cooperative knowledge sources and software. It consists essentially of the networked agents and the meta-system, each of which is a knowledge Petri net system with the capabilities of problem solving, learning and conflict resolution, and can be obtained through the inheritance, polymorphism and dynamic binding of instances of OOKPNs. In IIDAP system, both C/C++ language and COOL (CLIPS object-oriented language) are used to incorporate a Petri net tool, a geometric modeling and design tool, a planner and simulator and an evaluation tool. By use of this system, product design and assembly planning can be carried out simultaneously and intelligently in an entirely computer-aided concurrent design and assembly planning system. The design of manufacturable, cost-effective, usable products can therefore be achieved rapidly and flexibly. The developed methodology and system have been successfully applied to assembly design and planning of a micro switch, (C) 2000 Elsevier Science Ltd. All rights reserve
We all know that the web is a fantastic resource of information that can help us, but we also know that information is often hard to find. Website Wanderer is a column where we have invited an active researcher or dev...
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We all know that the web is a fantastic resource of information that can help us, but we also know that information is often hard to find. Website Wanderer is a column where we have invited an active researcher or developer in some area to share their knowledge of which websites are worth visiting. In this issue, we focus on patterns-encapsulations of knowledge that can be reused in some way when developing software.
In this paper we examine the structure of Maxwell equations in order to find clear signposts how to implement finite element software systems. The aim is to recognize the abstractions involved in Maxwell equations and...
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In this paper we examine the structure of Maxwell equations in order to find clear signposts how to implement finite element software systems. The aim is to recognize the abstractions involved in Maxwell equations and to exploit concepts of modern programming techniques, such as object-oriented design, to imitate the abstractions in numerical computing. As mathematics is the machinery to model physical phenomena, it is worth to imitate the same machinery in a software system. If a software system is constructed this way, it is partitioned into distinct components whose function is evident. And that is a basis for a software system that is modifiable and understandable, which are the main goals in software design.
Computer-aided management of surface-water quality has been a field of continuous progress in the last decades. object-orientation offers the potential for the development of efficient software tools, capable of deali...
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Computer-aided management of surface-water quality has been a field of continuous progress in the last decades. object-orientation offers the potential for the development of efficient software tools, capable of dealing with the complexity of water resources and their policy making. In the present work an object-oriented approach has been developed for the analysis of point-source pollution control in river basins. The physical entities of the river basin and the conceptual entities of its water-quality simulation and control have been represented through objects. With the appropriate distribution of responsibilities among these objects and the specification of their collaborations, the assessment and simulation of river water quality can be performed. Alternative strategies of point-source pollution control can be also evaluated, and an optimised control scheme can be suggested. The above analysis has been implemented in the design and development of an easily extended and flexible software tool, using the object-oriented language Smalltalk Express. The tool has been successfully validated through the studies of the South Nation River Catchment in Canada and the Upper Mersey River Catchment in the United Kingdom. In this work the architecture of the software tool is outlined and the employed mathematical analysis along with the results of the case studies are presented. (C) 1999 Elsevier Science Ltd. All rights reserved.
This paper presents a new object-oriented design of software for finite element calculations. Special attention is given to coupled problems with nonlinear materials. Fundamental ideas of object-oriented design, espec...
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This paper presents a new object-oriented design of software for finite element calculations. Special attention is given to coupled problems with nonlinear materials. Fundamental ideas of object-oriented design, especially high cohesion, low coupling and encapsulation of classes, are strictly taken into account. The concept is guided by the idea to reuse as many parts as possible, The hierachy of classes for the elements, materials and held problems can be extended easily by specialization.
Saving internal program data for further use is one of the most useful ideas in programming. Developing general features to provide such data saving/restoring is a very active research area. There are two application ...
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ISBN:
(纸本)3540676694
Saving internal program data for further use is one of the most useful ideas in programming. Developing general features to provide such data saving/restoring is a very active research area. There are two application areas for such features we believe to be crucial: system fault tolerance and data persistence. Our analysis shows that the features used in these areas have a lot in common: they are to flatten data of different types and save them in a store which can be used later on. The recent revision of the Ada language standard, Ada 95, introduces a new mechanism called streams that allows structured data to be flattened. Streams are sequences of elements comprising values from possibly different types. Ada 95 allows programmers to develop their streams following the standard abstract class interface. In this paper we show how to use the stream concept for developing new features to provide internal program data saving suitable for fault tolerance and persistence. A hierarchy of different storage types, useful in different application domains, is introduced. The standard stream interface is extended, making it possible for programmers to have a better control of the way streams work by separating storage medium control from the actual stream type using the design patterns. The convenience of this new interface is demonstrated by developing a generic package allowing any non-limited object to be written into a storage device. It can be used for providing data persistence and as a state restoration feature in schemes used for tolerating software design faults.
This paper presents a software model of agent-based competitive power systems. The model consists of software objects (agents) that represent individual system components and other administrative entities. Each of the...
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ISBN:
(纸本)0780359356
This paper presents a software model of agent-based competitive power systems. The model consists of software objects (agents) that represent individual system components and other administrative entities. Each of these agents has two characteristics: state (physical characteristics, limitations, record values, etc.) and behavior (operation and control, business strategies, performance, local and global interactions, etc.). An agent maintains its state in variables and implements its behavior with methods. We define software objects in terms of classes built by sets of attributes and member functions. The objects interact with each other via massage passing. These interactions are mapped into functional procedures reflecting objects' intelligence to optimize performance while ensuring reliable system operation. We give snapshots of the C++ code to illustrate developed concepts.
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