Forward Position Analysis of 5-DOF Parallel Mechanism

Forward position analysis is one of the importantand difficult issues in the kinematic analysis of paral-lel manipulators and has been extensively investiga-ted[1—3]. Most of the approaches for solving forwardposition problems of parallel manipulators with six de-grees of freedom (6-DOF), the Stewart platform forinstance, can be classified into two categories, i.e.closed-form analytical method using polynomial ap-proach and numerical method using iterative algo-rithm. Although the polynomial…     

教学电视片制作所需视频素材采集方法

要想制作精美的教学电视片需要大量视频素材,视频素材采集分为电脑内部采集、外部采集和自己制作视频素材等三大类。电脑外部视频采集就是从外部视频设备输出的视频信号经采集卡输入到电脑内,从而获取视频素材。内部采集是从现存素材盘上、网络上获取素材,或者利用动态屏幕抓图软件采集视频素材。自己制作就是用动画制作软件制作视频素材。     

有机静电感应三级管动作特性的实验分析

1 Introduction Organic semiconductors are receiving considerableattention due to their remarkable advantages especiallyvarious manufacturing methods ,lowcost and plentifulmaterials .Ebisawa ,et al.[1]fabricated the first poly-mer-based transistor in 1983 . Since then,lots of re-search works have been done in the filed of organicmaterial-based transistors .It was reported that organicthin-fil m transistor ( OTFT) fabricated by usingorganic semiconductor material copper-phthalocyanine(CuPc)[2…     

Simple shear endochronic eqiations for finite plastic deformation

The endochronic equations proposed by Valanis (1980) were extended to a finite deformation range. Jaumann's rate,Fu's rate and Wu's rate were incorporated into the endochronic equations to analyze simple shear finite deformation. Incremental equations and numerical solutions are deduced for three endochronic objective models. The results show that an oscillatory shear stress response to a monotonically increasing shear strain occurs when the Jaumann's rate objective model is employed for endochronic materials. The oscillatory response is dependent on the adopted objective rate. Compared with the Jaumann's rate, the Fu's rate and the Wu's rate satisfy the restrictions to elastic-plastic constitutive relations and are in agreement with the experimental results.     

论高职院校数控人才的培养

高职院校数控人才的培养要围绕专业大胆调整课程结构,切合实际加强专业基础教学,突出重点 强化专业操作训练。     

岩体工程数值模拟新方法——数值流形法(NMM)

数值流形法是最近发展起来的一种数值分析方法。阐述数值流形法的基本原理,介绍数值流形法在岩体工程中的几个应用实例,并对数值流形法的特点及其在岩体工程中的应用前景进行简要评价。     

英汉数字词语的认知比较研究

在英语和汉语这两种高度发展的语言中,存在着大量的数字词语。数字词语是语言词汇的重要组成部分,也是语言的民族形成和各种修辞手段的集中表现。这些数字词语由于民族文化、地理环境、经济生活和认知思维的差异而具有不同的文化内涵。     

提高数控编程课教学质量的探索

数控编程是一门新兴的、综合性、实践性较强的学科,要通过有限的课堂教学提高学生的数控理论知识水平,通过教学方法的改变提高学生的接受能力。要在课堂的理论教学中引入新的理念和方法的探索,提高教学质量,为培养紧缺人才做出贡献。     

模拟电路故障诊断方法浅析

叙述了模拟电路故障的特点及模拟电路故障诊断的传统方法和发展现状,着重分析了新近发展起来的人工智能、神经网络和小波分析在模拟电路故障诊断中的应用及前景.     

CQ5250立式车床的数控化改造

普通立车进行数控改造可以取得良好的经济效益和应用效果,有利于提高企业的生产力和竞争力。本文通过对CQ5250普通立式车床的分析,提出了刀架、数控及进给伺服驱动系统、主轴传动的数控改造方案。