局域动态一维版图压缩算法及其实现

本文给出了一种基于设计规则检查之上的一维版图压缩算法——局部的动态的一维压缩算法RDOC。这是一种特别适合于物理版图的算法,该算法建立约束图的运算时间是线性的,较以前的阴影传播法、垂直平面扫描法快,提高了压缩效率;本文还介绍了为实现该算法而开发的用于单元级版图的压缩程序,它允许用户按其需要对设计规则进行放大或缩小。最后给出了标准单元的压缩实例。     

研究CAD与VF的接口技术探讨设计、工艺、生产数据交换

深入研究开发CAD与VF的接口技术，实现设计数据向工艺、生产所用数据的转换与传递，缩短产品的设计与生产周期。     

产品重心缓冲包装计算机辅助设计法

提出了根据产品重心的不同,合理设计缓冲垫的方法,推导了计算公式,并编出了程序,使缓冲包装设计更加合理精确,从而节省缓冲材料。     

圆管冲圆弧模具CAD软件的研究与开发

本文介绍了利用VBA开发的圆管冲圆弧模具CAD软件及其程序设计问题。     

盐化工容器设备CAD设计中特征造型技术应用研究

文章提出特征造型技术在盐化工容器设备CAD设计的应用，使设计人员的操作对象不再是原始的线条和体素．而是在盐化工容器设备功能要素的更高层次上进行，直接体现设计者的设计意图，使建立的产品模型容易为非设计人员理解和便于组织生产，有助于加强产品设计、分析、工艺准备、加工检验等各部门之间的联系。提高设计制造的效率。     

转子动力学计算前处理功能软件开发

在传统应用传递矩阵法进行转子动力学计算的软件基础上，开发前处理软件的工作，解决传递矩阵法输入数据和转子分段的繁琐而又专业性强的工作，使转子临界转速、失稳转速和振动模态的计算软件的使用更为方便，而前处理软件主要解决了转子设计图纸的自动提取和转子的自动分段的功能。     

A scheme for the realization of graphical computer aided design systems

We present some of the problems encountered in the study of CAD systems in an electro-mechanical company, and propose a methodology based entirely on a detailed object study. In the first part of this paper we analyse the traditional design process in the company and define the most important functions of a CAD system. In the second part, we show how a functional hierarchical decomposition of the product helps us to realize the CAD system, and then we describe the practical application.     

Optimal design of linear control systems by an interactive optimization method

When designing linear control systems, one of the most difficult problems is that the designer almost has no theoretical basis for the determination of proper parameters in order to obtain a system with desired specifications. Poles and directions of eigenvectors in the pole assignment method or weighting matrices of the quadratic criterion function in the optimal regulator method are such parameters. The designer has to determine them by trial-and-error using computer simulation. The purpose of this paper is to propose an approach to helping determine proper parameters in linear control system design by the state space methods. In the case where the desired specifications are not given explicitly, the approach applies an interactive optimization method called the Interactive Simplex method to search the most suitable parameters directly in the parameter space. But, if the specifications are given explicitly, the design problem can be formulated as a multiobjective optimization problem. In this case, weights which indicate relative importance of different specifications are introduced and the Interactive Simplex method is applied in the weight space to indirectly find the most appropriate parameters. The approach is implemented as part of a CAD system. The designer has only to make pairwise comparisons of response curves which are shown on a graphics display terminal in order to obtain the most preferred control system. Two illustrative examples are demonstrated to indicate the efficiency of the approach.     

A study on product modelling for integration of CAD/CAM

Modelling capability for products to be designed and manufactured plays an important role in order to effectively construct and utilize CAD/CAM systems. Product models should represent all the information about products, which is utilized in manufacturing processes. Therefore it is required that they describe functional structures of machine products, and include not only geometric information but also various non-geometric data, such as physical, technological and management data. Presently there do not seem to exist definite methods or theories for constructing product models. In this paper, we first investigate the whole manufacturing process, and propose a system structure for integration of CAD/CAM, in which product modelling plays a fundamental role. Then requirements for product modelling are studied thoroughly, and a new representation framework for product models is proposed. It consists of an object concept called frame, relations among frames and attributes, and it can incorporate the existing various modelling capabilities, such as solid modelling. We use this representation framework in combination with our solid modelling package GEOMAP-III, and show the effectiveness of this approach by performing illustrative design experiments.