One of the most intriguing-and at the same time most problematic-notions in object-oriented programming is inheritance. Inheritance is commonly regarded as the feature that distinguishes object-oriented programming fr...
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One of the most intriguing-and at the same time most problematic-notions in object-oriented programming is inheritance. Inheritance is commonly regarded as the feature that distinguishes object-oriented programming from other modern programming paradigms, but researchers rarely agree on its meaning and usage. Yet inheritance is often hailed as a solution to many problems hampering software development, and many of the alleged benefits of object-oriented programming, such as improved conceptual modeling and reusability, are largely credited to it. This article aims at a comprehensive understanding of inheritance, examining its usage, surveying its varieties, and presenting a simple taxonomy of mechanisms that can be seen as underlying different inheritance models.
A good layout design is important for a cellular manufacturing system (CMS) to operate efficiently. Traditional algorithms for layout design are confining and have limitations with regard to decision factors and knowl...
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A good layout design is important for a cellular manufacturing system (CMS) to operate efficiently. Traditional algorithms for layout design are confining and have limitations with regard to decision factors and knowledge representation. Knowledge-based expert systems have opened up a new way for modelling and evaluation of the ill-structured CMS layout problem. In addition to the advantages of integrating the vast amount of available knowledge and making it accessible to ordinary users, the knowledge-based approach is also useful for dealing with ambiguous, qualitative information and empirical knowledge that are often part of the CMS layout design process. The objective of this research is to develop a prototype for CMS LAyout Design Expert System (CLADES) by using the expert system shell KEE (Knowledge Engineering Environment). This expert system would provide a powerful and efficient decision support tool for users in CMS layout design. CLADES solves the CMS layout problem in two stages. In the first stage, the machine cell layout is determined. In the second stage, the machine layout within each cell is determined. To obtain a reasonable layout design for a CMS, several factors which affect the decision are used as criteria in the CMS layout design problem. They are production quantity of the system, variation of part process routing, material handling system, unit load of an item, and dimensions of the floor plan. The design options considered by CLADES include three types of layout for machine cells, four types of layout for machines within a cell, and five types of material handling systems. In its current form, CLADES contains 58 rules, three models and three algorithms, and one algorithm is directly coded in CLADES in the LISP language. CLADES uses a tandem architecture, which connects the knowledge base to the model and algorithm base. This structure takes advantage of not only the expert system approach, but also the optimization approach. CLADES is code
An object-oriented data model for the elaboration of scanning probe microscopy information is proposed. This data model provides a comfortable interoperability between different types of data, presented as visual obje...
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An object-oriented data model for the elaboration of scanning probe microscopy information is proposed. This data model provides a comfortable interoperability between different types of data, presented as visual objects. On the other hand, this model correlates with modern compound document programming technology, and can be implemented within a client-server application, exploiting the benefits of distributed data systems. Such a data model is suitable for scanning probe microscopy image processing, and could be useful for some other research fields, allowing the integration of a huge amount of composite data.
In this paper, the bill of materials (BOM) system is defined as the central hub of a general product data management (PDM) system that provides essential data for running a manufacturing system to produce products. In...
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In this paper, the bill of materials (BOM) system is defined as the central hub of a general product data management (PDM) system that provides essential data for running a manufacturing system to produce products. Information that is relevant to products and their components is defined in the BOM. The information is critically related to data from product design, manufacturing planning, production management, procurement, inventory control, and accounting within a company. A conventional BOM structure (or product configuration), which manages data only in a stand-alone relational database management style, cannot satisfy the needs requested by all departments within a company. A BOM should relate to and communicate with other domains of the information system. In this research, a newly designed BOM system uses the object-oriented programming (OOP) concept to represent product information. The object-oriented BOM (OOBOM) system can capture and encapsulate data that will simultaneously serve the information needs of various departments. In order to manage product data dynamically, the system provides several interfaces for easy data access and manipulation. The linkage between BOM and its corresponding CAD/CAM system is enabled through the X-window manager: thus an integrated PDM environment is developed. This product management approach improves the consistency and efficiency of product data representation.
作者:
Thiery, RCREGU
BP 23 F-54501 Vandoeuvre-lès-Nancy Cedex France
A new global approach for calculating thermodynamic properties of fluids with equations of state is proposed. This method uses an object-oriented library, written in C++, and containing a number of routines that facil...
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A new global approach for calculating thermodynamic properties of fluids with equations of state is proposed. This method uses an object-oriented library, written in C++, and containing a number of routines that facilitate thermodynamic calculations. It is applicable to any equation of state formulated by an analytical expression of the Helmholtz free energy. The programming work of the user is limited to the building of a parse representation of the Helmholtz free energy. This parse graph is then processed by the program for analytically calculating the required derivatives and thermodynamic properties of fluids. A demonstration of this library is made with the Anderko and Fitter equation of state for H2O-NaCl-KCl fluids. The Helmholtz free energy has been differentiated analytically up to the fourth order with respect to the temperature, molar volume, and composition. Calculated derivatives are used to calculate the critical line of H2O-NaCl mixtures and other thermodynamic properties, which otherwise would be difficult to obtain. Copyright (C) 1996 Elsevier Science Ltd
An approach to the computer aided analysis of flexible multibody systems using object-oriented programming methods is presented. The aim is to support the rapid generation of specialized programs by providing an open,...
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An approach to the computer aided analysis of flexible multibody systems using object-oriented programming methods is presented. The aim is to support the rapid generation of specialized programs by providing an open, extensible C++ toolkit. This toolkit contains modules (C++ classes) which allow the declaration and manipulation of multibody components such as joints, bodies and actuators in an intuitive manner. New components (e.g., new finite elements) are easily introduced to extend the toolkit. The equations of motion for a multibody system consisting of these components are formulated by direct application of the principle of virtual work using symbolic techniques. It is possible to use absolute as well as relative coordinates in a problem-dependent manner.
As a response to the need for flexible manufacturing cells in high-technology industries, automated equipment has been developed in recent years, Also, factory-level integrated production control is belong developed i...
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As a response to the need for flexible manufacturing cells in high-technology industries, automated equipment has been developed in recent years, Also, factory-level integrated production control is belong developed in some industries using the potential of modern computer systems, A manufacturing cell is a group of automatic machines which must be controlled so as to behave as a single unit when viewed from the wider perspective. Cell-level control must be implemented to allow consistent automated operation of the cell and its efficient integration into the wider industrial process. Such a control system should provide high process and product flexibility, as well as high system maintainability. The general principles of automated cell control and robot control at the function and task Levels are therefore investigated in this paper, and the appropriate modelling and programming concepts analysed, A framework is developed which is appropriate for small, unmanned manufacturing cells comprising machine tools, robots and other automated equipment, both from the perspective of developing new software and extending, or re-engineering, existing software. The particular problems of using robots in such environments are also discussed, Copyright (C) 1996 Elsevier Science Ltd.
The Telecommunications Information Networking Architecture (TINA) Consortium is an international collaboration aiming at defining and validating an open architecture for telecommunication services for the broadband, m...
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The Telecommunications Information Networking Architecture (TINA) Consortium is an international collaboration aiming at defining and validating an open architecture for telecommunication services for the broadband, multimedia, and information era. The architecture is based on distributed computing, object orientation, and other concepts and standards from the telecommunications and computing industries. This paper provides an introduction to TINA.
In the theory of bosonic fields the calculation of Poisson brackets poses interesting technical problems using a symbolic calculus product such as Maple V. This article demonstrates how object-oriented techniques can ...
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In the theory of bosonic fields the calculation of Poisson brackets poses interesting technical problems using a symbolic calculus product such as Maple V. This article demonstrates how object-oriented techniques can be introduced to solve this problem and to obtain a neat and clearly structured Maple V package.
This paper presents a design of a knowledge-based simulation environment based on techniques from conventional simulation methods, object-oriented programming methods, and knowledge-based programming methods. The envi...
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This paper presents a design of a knowledge-based simulation environment based on techniques from conventional simulation methods, object-oriented programming methods, and knowledge-based programming methods. The environment has cooperating knowledge-based and simulation parts integrated into one modeling system. An idealized knowledge-based simulation model is presented along with a language for implementing such a model. This language is based on Symbolics Common Lisp with Flavors package. A model of the software development process is presented to illustrate the use of the knowledge-based simulation environment. This software development model is not intended to be a rigorous model of the software development process, but only to illustrate the use of the knowledge-based development environment which is presented in this paper.
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