可编程运动控制器的应用方法研究

重点论述了在现代大工业生产线中对控制器的选用原则和方法。介绍了作者所研制的应用于半导体器件生产线中的“多轴精密机械手”的设计思路、调试与标定创新。     

基于J2EE的网上企业建模系统

随着网络技术的发展，企业计算机应用的深度在加深，范围在扩展，传统的应用体系结构已经不能更好地满足企业需要。在这种情况下出现了J2EE（Java 2 Enterprise Edition）。本文介绍了J2EE的体系机构和在企业计算机应用系统开发中的优势，并结合作者开发的网上企业建模系统实例说明了基于J2EE结构的系统的开发过程和工作方式。该网上企业建模系统除了包括传统建模工具中的用户管理、模型绘制、模型管理、模型仿真等功能外，还增加了代码转换和成本分析功能。     

基于WEB面向供应链的ERP系统设计

分析某机床生产企业现有管理信息系统存在的问题,应用Internet/Intranet技术、Web技术和数据库技术,规划设计了适应企业生产发展的ERP系统,提出了面向供应链管理的系统总体结构模型和基于C/S和B/S相结合的系统体系结构。     

A Generic Part Orientation System Based on Volumetric Error in Rapid Prototyping

The paper presents the development of a generic part orientation system for rapid prototyping by considering the issue of volumetric error encountered in parts during the layer by layer building process in a rapid prototyping (RP) system. An algorithm is developed that slices the part with horizontal planes and computes the volumetric error in the part at different orientations by rotation about user-specified axes. The system recommends the best orientation based on the least amount of volumetric error in the part. The system has been tested using several examples of simple and complex parts. The generic part orientation system is believed to be first of its kind based on a volumetric error approach and will be useful for RP users in creating RP parts with a higher level of accuracy and surface finish, and also for intelligent process planning in rapid prototyping. RID=" ID=" <E5>Correspondence and offprint requests to</E5>: Assoc. Prof. S. H. Masood, CAD/CAM/CAE Group, Industrial Research Institute Swinburne, Swinburne University of Technology, Hawthorn, Melbourne, 3122 Australia. E-mail: smasood&commat;swin.edu.au     

Form Feature and Tolerance Transfer from a 3D Model to a Set-up Planning System

Currently, most CAD systems, even the feature-based design systems which were developed for CAPP, cannot provide exact information about an object (e.g. dimensions and tolerances). Some feature-based design systems can provide product data directly or indirectly; however, most CAPP systems still do not have an interface with CAD systems. The product data required by CAPP systems usually has a specific format which is unique to the system. In a CAPP system, it is essential for set-up planning to ensure the precision of the machining processes. Therefore, it is necessary to develop an interface with CAD models, so that the part data file can be obtained directly from the CAD representation. This paper proposes an approach for integrating the set-up planning system with a feature-based CAD system. By using an object-oriented approach – Product Data Translator (PDT), the computer-automated extraction of geometry and complete tolerance information was achieved; and the automated generation of the tool approach direction was developed. RID=" ID=" <E5>Correspondence and offprint requests to</E5>: H.-C. Zhang, Department of Industrial Engineering, Texas Tech University, Lubbock, TX 79409&ndash;3061, USA. E-mail: hzhang&commat;coe.ttu.edu     

嵌入式系统中千兆以太网的设计与实现

嵌入式系统中常常需要高速、稳定地传输大量数据,千兆以太网价格低廉、传输速度快、传输距离远,在高速计算机通信中被广泛使用。给出嵌入式系统中千兆以太网的设计方案、硬件设计及其软件实现,并对千兆以太网的性能进行验证。设计方案通用、灵活,能够满足嵌入式系统中高速数据传输的性能需求,为嵌入式系统的高速以太网络通信提供了一种很好的解决方案。     

Ex situ investigation of the proton exchange membrane chemical decomposition

The durability of Nafion^® polymer electrolyte membranes (PEMs) with potential application in PEM fuel cells has been investigated using accelerated durability tests to understand their degradation mechanism. After the attack by Fenton radicals, the Nafion^®111 membranes and the solution produced were collected for analysis. The existence of F ions in the solution indicated the chemical decomposition of the Nafion^® membranes during radical attacks. The F^- emission rate (FER) was about , corresponding to 0.024 wt% of F released from the membrane per hour. The NMR and FTIR spectrums demonstrated the polymer fragments mostly existed as whole side chains of the Nafion^® membrane. This result revealed that the degradation was originated from the decomposition of polymer main chain. Furthermore, the reflectance-FTIR revealed that the degradation of the PEMs was from the decomposition of the repeating units in the polymer main chains. With the increased loss of repeating units, small bubbles with the diameter of several microns started to form in Nafion^® membrane. These bubbles made the membrane vulnerable to hazards of gas crossover, which further led a catastrophic failure of the proton exchange membrane.     

校园手机一卡通系统安全性研究

在校园引入手机“一卡通”业务时,需在数据安全等方面不断探索和改进方能全面提升管理效率和管理水平。对影响手机一卡通系统的不安全因素进行了分析,在系统采用的密钥系统、卡片加密机制、通讯安全性、数据存储安全性等方面进行了研究与设计。     

加强大学生信息素养教育 提高人才培养质量

该文论述了信息素养的内涵,分析了提高大学生信息素养对人才培养的重要性,并提出一些提高大学生信息素养的具体措施。     

学生参与的大学校园景观设计研究—以清华大学为例

校园通过环境育人的作用潜移默化地影响着学生的成长,校园景观设计研究已成为设计类专业学生学位论文及设计课选题的主要对象之一。清华大学的教学与实践中,设计类专业学生参与校园景观营造的过程主要与其专业学习相结合,本科生与研究生各有侧重。非设计类专业学生是校园学生使用者中的多数,其参与过程以公众参与理论为指导,通过多种形式进行。合理进行资源整合与计划协调,校园景观设计研究可以成为学生价值塑造、能力培养、知识传授的理想平台。