国外CAD/CAM的发展和新战略

国外CAD/CAM的市场状况,几种有名的CAD/CAM软件支撑系统的特点,当前CAD/CAM支撑系统的发展战略。     

CAD/CAM 外部数据库系统的研究与应用

CAD/CAM 软件的二次开发越来越受人们的重视,而建立自己的数据库与 CAD/CAM 软件集成是重中之重。本 文在著名的 CAD/CAM 软件 PRO/E 的基础上,结合 VC.NET,用 ADO 技术对外部数据库的连接方法进行了研究,并根 据实际需求建立了一套属于自己的刀具数据库系统。     

开发自主版权CAD软件

我国主要采用引进国外的优秀软件与自主版权的CAD软件相结合的方式。国外许多著名的CAD软件厂商都看准了中国这一大市场,纷纷将产品引入国内。如Computer Vision、Intergraph、CATIA、SDRC/I-DEAS、CADAM、AutoCAD、Pro/Engineer等等。一般说来。国外引进的CAD软件功能比较齐全,商品化程度较高,软件运行都比较稳定。大多数国外CAD软件都具有三维造型设计的功能,并提供二次开发的工具,但是,这些软件又往往结构庞     

EDS与UG

如果以CAD/CAM软件所需要的硬件平台进行分类,则可分为两大类:运行于微机与运行于工作站上的CAD/CAM软件。一提起CAD/CAM,不禁马上想到工厂,在工厂中若处理复杂的工艺设计及加工任务,则难免要利用工作站,所以,我们来看看专门生产运行于工作站上的CAD/CAM软件的厂商及其产品。 每当我们去了解某类产品时,通常最想知道,这个领域中包括了哪些竞争者?他们的力量对比如何?让我们看看下面两张表:表1所示是Dataquest对1994年CAD/CAM/CAE/GIS软件北美工作站市场的份额表。表2所示是专门从事CAD/CAM和PDM(Product Data Management)市场调查的主要咨询公司CIMda-ta的一项调查结果。     

中望CAD/CAM教程:片体质量计算

三维CAD/CAM软件中望3D支持片体质量计算,这相比其他三维CAD软件是一大亮点,因为一般的三维CAD软件都需要将片体修复成实体才能计算质量。片体质量计算带给CAD用户的好处是:当用户接到客户产品文档时,需要针对产品进行报价,而这些产品往往都是经过了文件转换而存在一些缝隙(非实体),如果用其他三维CAD软件,就必须先花时间将实     

GMCADS系统的研究及应用

当今,机械CAD向CAD/CAM/CAE集成化方向发展,机械系统运动学/动力学分析软件是集成化CAD/CAM/CAE不可缺少的支撑软件之一。我们以多刚体系统动力学为基本理论,研制了面向问题的、交互式的通用机械计算机辅助设计系统GMCADS。本文介绍了GMCADS系统的分析原理、图形输出技术,并给出了应用实例。     

今日CV

创立于1969年的美国CV公司是全球CAD/CAE/CAM业界具有二十多年辉煌历史的计算机软件和服务公司,总部设在麻省贝德福德市。她开发、生产和销售世界一流的CAD/CAM软件系统,在世界范围内的机械CAD/CAM市场上一直处于领导地位。到1994年底,CV公司在世界范围内的软件装机总数超过25万套,形成了极为庞大的用户群体,对CAD/CAM工业的繁荣和发展产生了深远的影响。     

注塑模具CAD/CAE数据接口技术

本文针对目前注塑模CAD/CAE/CAM集成系统中尚无专用的几何造型软件通过对注塑模CAD,CAE的几何模型数据结构分析,采用数据接口技术实现注塑模CAD与CAE的几何模型转换。     

读编往来

浙江读者 肖尧先编辑同志,您好！我长期从事CAD/CAM软件应用与开发工作,实践中发现对于一些大型的CAD/CAM软件,在无人指导的情况下自己摸索会花费许多精力。倘若贵刊能刊载一些应用型的文章,对自学者来说可起到事半功倍的效果,因此建议贵刊开辟一个专栏介绍流行CAD/CAM软件的使用方法及技巧。编辑回答正如肖老师所提到的,对于初学者来说,掌握大型CAD/CAM软件的使用方法确实不是一朝一夕的事。目前,我国的很多企业正在为进一步普及三维CAD而努力着,缺乏人才是这一进程中的几大障碍之一。作为编辑我们有责任帮助那些对CAD…     

CAD/CAM软件在电子组装领域中应用技巧实例

如今CAD/CAM软件已被广泛应用于电子行业,摆在我们面前一个很现实的问题就是如何从CAD/CAM系统中得到用于生产的必要数据,建立起CAD设计系统和自动化组装设备之间的有机联系,提高电子制造的效率和质量。本文以作者的经验为例。介绍了CAD／CAM软件在电子组装领域中的一些应用技巧实例,希望能对相关技术人员有所帮助。     

基于Asp.net技术E-learning Centre平台的研究与设计

E-Learning是一种全新,便捷和有效的学习模式。它在提高教育教学质量,挖掘教育的发展潜力方面发挥着重要的作用。介绍了E-learning Centre网站平台的相关理论及技术背景,针对平台的功能,提出了使用ASP.NET技术构筑E-learningCentre(电子化学习中心)平台,探讨采用B/S(Browser/Server)架构体系开发E-learning Centre平台的概要设计。     

eGovernment in Victoria ‐ evolution of a resource centre

In 1995 the Victorian Government set an ambitious target to have all suitable government services online by the end of 2001. A knowledge management process was put in place to share government online learnings as they evolved. One of the outputs of this knowledge management process was the Government Online Resource Centre ‐ a web based repository made available to the Victorian Public Sector on the Victorian Government Intranet. This resource was subsequently published on the Internet in December 2000. In March 2002, the Victorian Government launched ‘Putting People at the Centre’ ‐ the Victorian Government's eGovernment vision. The Resource Centre was relaunched as the eGovernment Resource Centre. Governments and organisations worldwide are now actively seeking out this website to promote their eGovernment programmes.     

From Concordances to Subject Portals: Supportingthe Text-Centred Humanities Community

This paper discusses selected aspects of the work ofthe CTI Centre for Textual Studies, a Centre which hasits roots in a 1984 initiative and ceased to operatein 1999. The work of the Centre was grounded inhumanities computing, a subject area which itself hasdeveloped over time. The article compares earlierobservations made by Joseph Raben and Susan Hockeyabout the integration of resources within humanitiesteaching and learning, to current realities. Its focusis the development of access to distributed resources,beginning with an interface between the early PC andthe mainframe and ending with a vision of a humanitiesportal to distributed resources.     

CAE centre—a way of linking university to industry

A CAE Centre has been set up at Herriot-Watt University in an attempt to broaden the understanding, within industry, of CAE concepts and techniques. It also carries out research into related fields. This paper outlines some of the work being carried out at the Centre. In particular, it examines the role it plays in encouraging education in CAE by running courses, providing facilities for students and promoting research into CAE. The development of the Centre and its facilities is described and future trends in the financing of education, though industrial links are also discussed.     

A Global Ticket-Based Access Scheme for Mobile Users

This article presents a ticket-based access model for mobile services. The model supports efficient authentication of users, services and service providers over different domains. Tickets are used to verify correctness of the requested service as well as to direct billing information to the appropriate user. The service providers can avoid roaming to multiple service domains, only contacting a Credential Centre to certify the user's ticket since tickets carry all authorization information needed for the requested services. The user can preserve anonymity and read a clear record of charges in the Credential Centre at anytime. Furthermore, the identity of misbehaving users can be revealed by a Trusted Centre.     

A model to manage a large number of transactions: a case study

The aim of this paper is to present a model for the Computer Centre of an important Italian banking group. The model groups data and transactions to deal with the large dimension of the Centre. The transactions arrivals are considered as Posson stochastic variables and the probability values are estimated. Some computational results are given.     

Autonomous underwater vehicles for scientific and naval operations

Recognizing the potential of autonomous underwater vehicles for scientific and military applications, in 1997 MIT and the NATO Undersea Research Centre initiated a Joint Research Project (GOATS), for the development of environmentally adaptive robotic technology applicable to mine counter measures (MCM) and rapid environmental assessment (REA) in coastal environments. The August 2001 GOATS Conference marked the end of this 5 years project, but did not mark the end of the work. The Centre initiated in 2002 a new long-term programme to explore and demonstrate the operational benefits and performances of AUV for covert preparation of the battlespace. Recently the work addressed the evaluation of commercial off-the-shelf (COTS) AUV technology for MCM operations in response to terrorist mining of port. The paper summarizes the work performed and refers to the scientific publications derived from the AUV programme at the NATO Undersea Research Centre.     

Layer average relative humidity from SAPHIR on board Megha-Tropiques: validation with numerical model analyses

Subsequent to the launch of the Sondeur Atmosphérique du Profil d’Humidité Intertropicale par Radiométrie (SAPHIR) sensor on board the Megha-Tropiques satellite on 12 October 2011 from Satish Dhawan Space Centre, Indian Space Research Organization (ISRO), Shriharikota, India, the validation of layer averaged relative humidity (LARH) retrieved from SAPHIR has been initiated in different phases along with other retrieved parameters. The Megha-Tropiques is a joint satellite mission executed by the Indian Space Research Organization (ISRO) and the Centre National d’Etudes Spatiales (CNES), and is primarily devoted to study the tropical atmospheric processes influencing both weather and climate. The present study focuses on a validation campaign, where the validation of LARH derived from SAPHIR is carried out with three different numerical model analyses: the European Centre for Medium Range Weather Forecasts (ECMWF) model, the National Centers for Environmental Prediction (NCEP) model, and the National Centre for Medium Range Weather Forecasting (NCMRWF) model, over a period of six months from January 2013 to June 2013. It is observed that the root mean square difference (RMSD) of LARH has improved considerably for layers 1, 2, 3, and 6, and some marginal changes for layers 4 and 5, when a bias correction is applied to the data. The RMSD of SAPHIR LARH after correcting for bias is well within the range of the mission goal of 20% accuracy.     

Project report: the use of pilot to teach information technology concepts

Involving students in learning a small amount of programming language can enable the teacher to illustrate many of the important concepts of electronic information systems. It introduces them to experiential learning situations involving system design and operation, information handling and the man-machine interface. This paper describes how the authoring language PILOT has been used with arts and humanities undergraduates to increase their understanding of the power and potential of information technology, and to involve them in information problems that relate to their other humanities studies.Paul D. Nixon is currently Director of The Centre for Informatics at St. David's University College, Lampeter, Wales, U.K. The work at the Centre has been focussed on the development of information technology education for undergraduate and post-graduate humanities students.     

A review of: “Stochastic Choice of Mode in Urban Travel”: A Study in Binary Choice. By STANLEY LEON WARNER (Northwestern University Press.)

The following abstracts are of work of ergonomic interest which have appeared in other journals and research reports. They are a selection from the quarterl‘Ergonomics Abstracts’ which is published by the Ergonomics Information Analysis Centre, Department of Engineering Production, University of Birmingham, England. This journal offers a comprehensive annotated bibliography of current ergonomics publications. By special arrangement, its contents, printed on unbound adhesive backed sheets, are available at reduced rates to members of national ergonomics and human factors societies on application to the Centre. Selections of the information in the Centre's continuing collection, currently totalling some 64,000 abstracts, are available through special bibliographies prepared on request, and may cover any of the recognized subject headings in the field of ergonomics.