Object-oriented design for manufacture

Economically effective and timely product manufacture requires that appropriate decisions are taken during the design of the product. Recent years have seen very considerable growth in the study and communication of knowledge in the area of design for manufacture (DFM). At the same time there have appeared many additional pressures on the design process: rapid changes in market requirements, evolution and revolution in product and process technologies, legislated strictures and liabilities, and quality and cost issues which must increasingly be addressed earlier in the course of product design. As a consequence there is a strongly perceived need to enhance design methods in order to address the many disparate aspects of design in an efficient manner. In this paper the DFM problem is addressed within this larger context. The approach described in the paper begins with the hypothesis that the concept of manufacturability can be established as one of a number of required attributes of a part which is to be designed and manufactured. An information model is then proposed which provides the potential to allow determination of manufactur-ability to be made in an ongoing fashion in parallel with other design activities. The nature of the information model is shown to be in harmony with object-oriented programming environments. Finally, the information model is used to illustrate the potential to embody the large body of DFM knowledge which is already in existence but which has yet to be systematically encoded.     

Object-oriented programming for engineering applications

The object-oriented programing (OOP) methodology is introduced as a means for improving the management of a complex engineering software. The drawbacks of existing engineering software development techniques are pinpointed. The basic concepts of the OOP methodology are interpreted in the context of engineering applications. The familiar concept of a matrix is used as an example to interpret the ideas presented. It is concluded that the OOP methodology facilitates the management of complex engineering software systems.     

一种面向对象的专家系统设计方法

近年来,已经有不少面向对象技术运用于专家系统的研究。该文提出一种新的面向对象专家系统的设计方法。首先介绍系统总体结构,给出知识表示模型和推理机制,并且引入RMG的概念,进一步提出运用RMG完成推理过程的算法。最后把提出的方法应用于中西医结合糖尿病诊疗专家系统的开发。实践证明此方法是有效的。     

Object-oriented landmark recognition for UAV-navigation

Computer vision is an ever more important means for the navigation of UAVs. Here we propose a landmark recognition system looking for salient man-made infrastructure. An object-oriented structural system is preferred since it can utilize known properties of these objects such as part-of hierarchies, mutual geometric constraints of parts, generalization etc. The structure, available for use as landmark, will vary strongly with the region the UAV is supposed to navigate in. Clear object-oriented coding of the knowledge on the landmarks, their constraints, and their properties is a key to swift adaption. This contribution reports on an example: Adapting a system, designed for a central European country (Germany), for use in a more Eastern region (Turkey).     

Message Filters for Object-oriented Systems

In the conventional object model, encapsulated objects interact by messages that result in method invocations on the destination object. A message is delivered directly at the destination object. As a result of the direct deliveries, the message control code performing intermediate message manipulations cannot be abstracted out separately from the message processing code in the destination object without sacrificing the transparency of the intermediate message control. We propose the filtered delivery model of message passing for object-oriented languages to provide the separation of message control from message processing in a transparent manner. An interclass relationship, called a filter relationship, is introduced. As a consequence, a filter object can intercept and manipulate messages sent to another object called its client via filter member functions. A filter member function in a filter object can intercept a particular member function invocation on its client object. The filtered delivery model supports both upward and downward filtering mechanisms, facilitating interception of an upward message and its return message value. Filter objects can be plugged or unplugged at runtime. Binding of filter member functions to corresponding member functions in the client is selective and dynamic. The filtered delivery model is developed for the C++ object-oriented language; its applications are described and implementation is discussed. © 1997 John Wiley & Sons, Ltd.     

面向对象设计的质量模型

提出了改进的评价面向对象设计高层质量属性的层次模型,能应用在软件生命周期的早期,以保证软件产品的分析和设计有令人满意的内部质量属性。此模型用一套面向对象度量、评价类和对象的结构和行为特性,以及它们之间的联系,并将面向对象设计特性和高层质量属性相关联。此模型中的关联关系、权值能被容易地修改以适应多种不同的需求。     

面向对象有限元程序的研究

阐述了采用面向对象的方法和ＶＣ＋＋语言,进行结构问题有限元程序开发的过程。建立了一般线弹性体结构有限元分析类库,并与过程化语言的程序设计方法进行了分析比较,说明面向对象方法改善了有限元程序的维护性和扩充性,为开发工程计算程序提供了一种新途径。     

Object-oriented programming for structured procedural programmers

Object orientation is attracting much attention these days but may still be unfamiliar to some. This tutorial illustrates the differences between the object-oriented and structured-procedural programming (SPP) paradigms using working programs. It also shows how to migrate from the SPP methodology to object technology     

Object-oriented programming for engineering software development

The representation of engineering systems in a manner suitable for computer processing is an important aspect of software development for computer aided engineering. The process of abstraction is a well-known technique for developing data representations. Objects are a mechanism for representing data using abstraction, and object-oriented languages are languages for writing programs to manipulate objects. The paper shows through examples the advantages of object-oriented programming for developing engineering software. Mathematical graphs are used as an abstraction for two problems: (1) sorting activities in a schedule and (2) ordering nodes and elements in a finite element mesh. Classes of objects are developed for generic graphs, activity procedence graphs, and graphs of elements meshes. Object-oriented program development leads to modular programs and a substantial reuse of code for the two problems.     

Theoretical and applied aspects of the mathematical apparatus of permutation-masking transformations

We develop the mathematical apparatus of permutation-masking transformations (PMTs) of different types, enabling us to assign the full set of possible images to the initial generating function. We study the algebraic, spectral, and autocorrelation properties of these transformations. We substantiate the possibility of constructing complex broadband (in the frequency sense) images based on a simple generating function. We study the action of these transformations on stationary random processes, in particular, noncorrelated ones (of the white noise type). The developed apparatus can be applied in many areas, in particular related with the synthesis of the optimal ensembles of signals for communication and management systems; sounding signals for problems of radio-location and navigation; and coding, masking, and enciphering information; and also optimal signal processing in noisy conditions. We consider a demonstrational model example showing the possibility of raising the resolution and estimating quality of the signal parameters on the base of a modified correlator.     

面向对象的智能化FMS调度仿真

该文在分析传统数学方法和实验仿真方法的基础上，提出了一个求解ＦＭＳ调度问题的智能决策系统，使用面向对象的方法，构造了一个专家系统和仿真技术集成的调度模型，并进行了仿真实验分析。     

基于面向对象XML数据的索引机制

XML正在迅速成为Internet上信息表示和数据交换的重要标准.而面向对象的特征具有很强的建模能力,将面向对象的概念引入到XML可以提高XML模式语言的建模能力.而现有的索引模式都不支持面向对象XML数据的查询,由此提出了一种基于面向对象XML数据的OOCtree（Object-Oriented compact tree）索引模式,它是一棵包含组级和元素级的两级双向树.组级提供简洁的结构概要和继承信息,可以在查询早期阶段裁剪大量的搜索空间;元素级提供详细的孩子父亲连接关系,可以快速地访问某元素的父亲,极大地提高了查询处理效率.     

Object-oriented visualization

Feature based techniques incorporated into standard visualization algorithms can greatly enhance the quantification and visualization of observed phenomena, as described in the article. The methods to isolate and recognize coherent 3D structures are analogous to 2D vision techniques. The overall goals are the same in both fields, namely, to interpret an image (data) and construct a model to describe it. Although the article uses data sets from numerical simulations of fluid flow, the concepts are applicable to other domains where scientists study the evolution and morphologies of 4D space time vector and scalar fields. More work is needed to explore complex features based upon domain specific knowledge and to define the parameters for classification and tracking. Sophisticated databases for storage and retrieval of feature based data sets are also an interesting area of study. The ultimate goal of visualization is to aid in the understanding and analysis of data. With faster parallel computers and more sophisticated laboratory equipment, information is being produced in ever greater amounts. This information must be presented to the scientist in a form suitable for cogent assimilation and manipulation. The article presents issues and algorithms for an object oriented approach to this problem and demonstrates its usefulness for visualization     

面向对象的加成聚合反应动力学模拟系统

聚合反应工程建模中,多以机理建模为主。因此,在聚合过程中的计算机辅助设计软件中,对动力学的模拟就尤为重要。本文用面向对象的设计思想,提出了符合CAPE-OPEN技术标准的加成聚合反应动力学模拟系统的思路,并用C 给出了其实现。该软件能动态生成物料衡算方程和矩力方程,并将模型与求解器分开,具有良好的开放性。该系统既适用于专业用户,又适用于没有计算机建模背景的人员使用。     

面向对象的加成聚合反应动力学模拟系统

聚合反应工程建模中,多以机理建模为主。因此,在聚合过程中的计算机辅助设计软件中,对动力学的模拟就尤为重要。本文用面向对象的设计思想,提出了符合CAPE-OPEN技术标准的加成聚合反应动力学模拟系统的思路,并用C++给出了其实现。该软件能动态生成物料衡算方程和矩方程,并将模型与求解器分开,具有良好的开放性。该系统既适用于专业用户,又适用于没有计算机建模背景的人员使用。     

LR方法基于车间调度问题的面向对象设计

针对拉格朗日松弛方法解决不同车间调度问题时,对问题的依赖性强,算法实现复杂的情况,通过分析拉格朗日方法解决不同车间调度问题的特点,提出了拉格朗日算法面向时象的设计方法,并开发了通用的类模块;面向对象的模块关系和类层次使得算法可扩展性强,便于改进。仿真结果表明,用户可以方便地实现拉格朗日方法对多种车间调度问题的仿真,大大提高了代码的可重用性和软件的通用性。