SWL550型十字轴万向联轴器结构建模及有限元分析

利用现代设计技术对SWL550型十字轴万向联轴器进行结构设计及强度计算.通过对十字轴万向联轴器的力学分析,得到重要零部件的载荷边界条件.基于CATIA 软件建立重要零部件模型,通过CATIA的有限元分析模块对其进行有限元分析,危险截面的Von Mises应力与理论计算值基本吻合.用数字化模型代替传统的实物联轴器实验,简...     

基于有限元法液压支架底座的结构优化

为提高液压支架底座的可靠性和稳定性,对ZZC8800/20/38型六柱支撑式固体充填液压支架底座进行有限元分析;建立底座模型并进行分析,确定其危险工况和其加载的方式;建立有限元模型并对其分析,确定了应力集中和位移变形最大位置以及每种危险工况的加载方式。根据有限元的分析结果,对底座结构进行拓扑优化,并以质量、最大应力和最大变形位移为优化目标,进行尺寸优化。优化后底座最大应力最大减小了79.7%,最大变形位移最大减小了53%,质量减少了3.7%,底座的整体强度得到了提高,同时实现了底座的轻量化,疲劳损伤和变形位移较小,达到了预期的优化目的,安全系数均得到了提高。     

客车空气弹簧悬架边界条件模拟与试验验证

针对客车车架强度分析时空气弹簧悬架边界条件难以设置的问题,提出使用等效静态载荷法进行悬架模拟的思路。分析空气弹簧刚度的非线性和双横臂独立悬架的机构模型,建立整车多体动力学模型,计算多工况下车架与空气弹簧悬架连接位置处的受力,求解得到等效静态载荷并施加到有限元模型中,添加辅助约束完成边界条件设置;对车架进行多工况下的强度分析,比较不同工况下车架的应力分布和最大应力出现的位置。搭建试制样机的动态测试平台,对比仿真结果与试验结果,验证模拟方法的有效性。     

大型转炉倾动机构扭力杆有限元分析

应用有限单元法对大型转炉倾动装置的重要部件扭力杆进行应力应变分析,通过对正常工作状态和事故状态两种工况下扭力杆的变形及最大剪应力状态分析,确定出变截面扭力杆的强度,为产品设计提供依据.     

斜切工况下采煤机滚筒截割煤岩仿真分析

为研究斜切工况下采煤机滚筒的运动规律及受力特性,利用ADAMS建立了斜切工况下采煤机虚拟样机模型,通过运动仿真得到了斜切工况下采煤机滚筒运动曲线,并以该曲线作为滚筒运动边界条件;采用LS-DYNA对斜切工况下采煤机滚筒截割煤岩进行了模拟仿真,得到了斜切工况下滚筒受力特性。仿真结果表明:斜切工况下滚筒的截割阻力和牵引阻力逐步增大并最终趋于稳定,且截割阻力约为牵引阻力的2倍;滚筒轴向力呈先增大后减小趋势,最大轴向力出现在滚筒轴向位移达到最大时,且滚筒轴向力与轴向位移密切相关;滚筒力矩主要由截割阻力和轴向力产生,且力矩大小变化趋势与产生力矩的作用力的变化趋势一致。     

基于静强度分析的轻轨车辆弹性车轮参数设计

针对弹性车轮比传统刚性车轮结构复杂且影响车轮强度和寿命因素也更多的问题,通过CAD/CAE仿真软件建立某弹性车轮的有限元模型,基于EN 13979-1:2003标准,用Abaqus分析在直线工况下橡胶预压缩量、轮轴过盈量和减重孔数量对弹性车轮静强度的影响.对比不同方案下的静强度应力结果,给出一组合理的设计参数.在直线、曲线和道岔工况下的静强度校核结果表明该弹性车轮符合标准.     

基于动力学仿真的系留气球鼻锥有限元分析

针对系留气球进行了动力学仿真分析,在此基础上对一种用于固定球体的新型鼻锥结构进行了结构有限元分析,以确定其强度与刚度.首先采用计算流体力学CFD求得特定风速下系留气球所受的气动力,随后通过多体动力学软件Adams进行动力学仿真分析,确定作用在鼻锥上载荷的大小,并以此作为有限元分析的载荷边界条件;然后采用有限元分析的方法对鼻锥结构进行静力学和动力学分析;最后确定极限风速下艇首与鼻锥连接处的变形、载荷及应力情况.通过分析,为新型鼻锥结构进一步的设计改进与优化提供了参考依据.     

某型圆柱螺旋弹簧设计与疲劳寿命分析

圆柱螺旋弹簧是某型机械传动系统的关键部件,其设计的可靠性直接影响该结构的稳定和安全.首先对某型圆柱螺旋弹簧进行工况分析,进而基于机械设计原则对其刚度、强度进行理论校核,最后基于有限元应力仿真,在MSC Fatigue中计算出该弹簧最危险节点的寿命.所得结论表明设计弹簧的疲劳寿命满足疲劳可靠性的要求.     

210 t转炉连接装置的有限元分析及强度校核

利用ANSYS Workbench对某210 t转炉整体模型的三种极限工况进行有限元分析,得到转炉系统的应力分布和总变形,同时得到连接装置各个零部件的应力分布,找出零部件的最大应力值及所处位置,并结合有限元计算结果对各个零部件进行强度校核.结果表明连接装置的强度满足要求。     

基于ANSYS的兆瓦级风力发电机组机舱罩分析仿真

通过有限元分析能对极限风载下机舱罩结构强度进行有效分析仿真.本文首先研究了某新型机舱罩关键部件--上机舱罩在极限风速条件下的受力分析理论模型,以及ANSYS三维有限元分析的基本步骤,并在此基础上介绍了利用ANSYS软件建立上机舱罩三维有限元模型,设定有限元分析参数,约束边界条件,施加外部载荷等具体操作方法,从而构建了一种基于ANSYS的大型兆瓦级风电机组机舱罩受极限风载时的三维有限元分析仿真方法.     

Only connect: teaching, technology and telesis

Abstract This paper describes an approach to the design of interactive multimedia materials being developed in a European Community project. The developmental process is seen as a dialogue between technologists and teachers. This dialogue is often problematic because of the differences in training, experience and culture between them. Conditions needed for fruitful dialogue are described and the generic model for learning design used in the project is explained.     

Avoiding semantic and temporal gaps in developing software intensive systems

Development of software intensive systems (systems) in practice involves a series of self-contained phases for the lifecycle of a system. Semantic and temporal gaps, which occur among phases and among developer disciplines within and across phases, hinder the ongoing development of a system because of the interdependencies among phases and among disciplines. Such gaps are magnified among systems that are developed at different times by different development teams, which may limit reuse of artifacts of systems development and interoperability among the systems. This article discusses such gaps and a systems development process for avoiding them.     

Designing economic np control charts: A programmed simulation approach

This paper presents control charts models and the necessary simulation software for the location of economic values of the control parameters. The simulation program is written in FORTRAN, requires only 10K of main storage, and can run on most mini and micro computers. Two models are presented - one describes the process when it is operating at full capacity and the other when the process is operating under capacity. The models allow the product quality to deteriorate to a further level before an existing out-of-control state is detected, and they can also be used in situations where no prior knowledge exists of the out-of-control causes and the resulting proportion defectives.     

The development of robot art

Going through a few examples of robot artists who are recognized worldwide, we try to analyze the deepest meaning of what is called “robot art” and the related art field definition. We also try to highlight its well-marked borders, such as kinetic sculptures, kinetic art, cyber art, and cyberpunk. A brief excursion into the importance of the context, the message, and its semiotics is also provided, case by case, together with a few hints on the history of this discipline in the light of an artistic perspective. Therefore, the aim of this article is to try to summarize the main characteristics that might classify robot art as a unique and innovative discipline, and to track down some of the principles by which a robotic artifact can or cannot be considered an art piece in terms of social, cultural, and strictly artistic interest. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008     

Call for Papers The 6^th International Conference on Grid and Cooperative Computing

Recent years have seen rapid advances in various grid-related technologies, middleware, and applications. The GCC conference has become one of the largest scientific events worldwide in grid and cooperative computing. The 6th international conference on grid and cooperative computing (GCC2007) Sponsored by China Computer Federation (CCF),Institute of Computing Technology, Chinese Academy of Sciences (ICT) and Xinjiang University ,and in Cooperation with IEEE Computer Soceity ,is to be held from August 16 to 18, 2007 in Urumchi, Xinjiang, China.     

Call for papers The 34th Chinese Control Conference & SICE Annual Conference 2015

正The 34th Chinese Control Conference and SICE Annual Conference 2015(CCCSICE2015)is organized by the Technical Committee on Control Theory(TCCT)of Chinese Association of Automation(CAA)and the Society of Instrument and Control Engineers(SICE)of Japan,and locally organized by Hangzhou Dianzi University(HDU).     

一种主题爬虫文本分类器的构建

该文利用DF与CHI统计量相结合的特征选取方法,针对互联网上对外汉语相关领域的网页进行特征提取,并在此基础上,构建了基于标题与正文相结合的两步式主题相关度判定分类器。基于该分类器做对外汉语相关主题的网页爬取工作,实验表明,效率和召回率比传统分类器都有较大程度的提高,目前该分类器已经用于为大型对外汉语语料库构建提供数据源。     

A 3-D motion tracing system in High School Physics teaching

Abstract This article presents a study of a large scale incorporation of one data acquisitionsystem into physics teaching in Israel. By 1994 about 30% of the schools throughout the country used the V-scope, a 3-D multibody motion tracing system, in their lab programme. The views and reactions of post-training teachers, experienced teachers and students on various aspects of using the system are described, analysed and compared.     

基于蚁群算法自整定PID的风电系统最大风能追踪研究

针对风力发电系统处于欠功率阶段时,风能利用系数须保持在最大值的问题,以欠功率阶段的最大风能追踪为研究重点,对风力机捕获风能的过程进行理论分析,提出了一种基于蚁群算法自整定PID的最大风能追踪控制策略,利用蚁群算法的全局优化能力优化PID的3个参数,给出了该算法的基本思想以及具体实现步骤,设计了蚁群算法自整定PID控制器,搭建了系统仿真图,并对其进行相应的仿真分析;仿真结果表明,与传统的PID控制策略相比,该控制策略使控制系统具有良好的动态响应能力,提高了风电系统的控制精度、风能利用率、输出功率,实现了机组的优化运行.     

Young children's active and passive graphing

Abstract This paper reports on the graphing work of children, aged 8 and 9 years, who have immediate and continuous access to portable computers across the whole curriculum. They have been using their computers to generate graphs and charts from experimental data. The unit of analysis is a learning sequence in which the progress of a small group of children on a specific coherent task was recorded over a period of several weeks. The paper describes two such learning sequences to illustrate two types of graphing, which can occur in computer-rich environments. In one sequence, the children collected data after which they explored the graphing facilities on the computer whereas in the other learning sequence graphing is used iteratively as an integral part of the ongoing task.