智能夹具的设计与实现

以EPMA7256AETC144-10为核心设计了具有顺序提示、错误报警和错误计数功能的智能夹具。采用VHDL语言和原理图两种方式实现CPLD内部逻辑功能设计,采用MAX PLUSⅡ软件进行编译、仿真。该夹具经过测试后性能稳定,很好地实现了各项功能。     

三维组合夹具元件库的建立

夹具构形设计是先进夹具自动设计系统中重要的组成部分 .合理的构形图首先要有三维组合夹具元件图 .采用 ARX技术开发了三维组合夹具元件库 ,直接为基于变异特征的夹具安装规划及构形设计系统服务 .介绍了 ARX的功能、建库方法及库的管理和应用实例 .图库包含了常用的组合夹具元件 ,还实现了相应的功能 :组合夹具元件图的插入、扩充、查询、输出及制作幻灯片等     

基于SolidWorks的参数化组合夹具二次开发技术

目的基于VC开发组合夹具标准件零件库,与SolidWorks三维软件无缝对接,建立人机对话界面,实现组合夹具快速设计,解决传统夹具设计时存在建模过程繁琐,设计方案修改周期较长等缺陷。方法以SolidWorks三维设计软件为平台,采用尺寸驱动法,通过三维软件提供的API来调用三维软件本身的功能,以开发出用户所需的特定功能的软件模块。结果建立参数化组合夹具元件各种类型系列化三维标准件零件库,用户按照需要输入参数,驱动已有三维模型,实现参数化建模、夹具快速设计、优化及虚拟装配。结论实例表明,基于SolidWorks的组合夹具二次开发技术,可实现一次建模多次重复调用,该方法对组合夹具设计和虚拟装配技术提供了较好的研究平台。     

夹具概念设计中功能推导的研究

介绍了夹具自动设计中概念设计的必要性 ,提出了夹具概念设计的方法 ,给出了夹具概念设计中的功能推导的基本思路及具体实现     

机床夹具计算机辅助设计系统开发

本文介绍了一种以工程数据库为支撑,以ＡｕｔｏＣＡＤ软件为平台的机床夹具计算机辅助设计软件开发的方法,主要由夹具零件分类管理和夹具零件ＣＡＤ两部分组成,能够实现夹具标准件与非标件的设计、绘图等功能,可有效地提高机床夹具设计的速度和质量。     

组合夹具计算机辅助设计系统研究

本文介绍了一种基于MDT的组合夹具计算机辅助装配系统 ,简要介绍了组合夹具元件图库的建立 ,组合夹具的装配与定位误差分析。采用面向对象开发环境VC ++作为界面开发工具 ,利用ODBC技术实现数据库链接 ,采用Autodesk公司自身提供的ARX接口实现在MDT下应用程序的加载。     

知识驱动的夹具CAD系统

介绍了知识驱动的夹具CAD系统结构和功能。着重讨论实现中的关键技术：知识的表示、数据库的构造等。     

复合材料加筋结构剪切屈曲模态分析

复合材料加筋壁板逐渐应用于大型飞机机身及机翼结构,采用试验和有限元的方法研究了加筋壁板结构的剪切屈曲特性。通过剪切试验获得加筋壁板结构的屈曲载荷和破坏载荷,结果表明当结构达到屈曲状态时并不会立马丧失承载能力,屈曲载荷占破坏载荷的81.8%。对比含夹具和无夹具的剪切屈曲载荷可知,夹具对加筋板的屈曲稳定性影响较大,在进行仿真模拟时,忽略夹具可能导致严重的错误。同时,边界条件的差异会导致结构的屈曲稳定性发生改变,夹具的强弱会影响结构的传力路径,合适的边界条件可以极大地改善结构的稳定性。     

24路光电开关测试夹具电控系统的设计

随着先进技术的引进和高端产品的出现,电子产品越来越小型化、复杂化,电路板亦趋于多层、高功能和高密度,因此,对其检测工作提出了更高层次的要求.大批量生产的电路板,常采用测试夹具进行在线测试.测试夹具的设计和制作过程比较复杂,该文对24路光电开关测试夹具电控系统的设计进行了简要探讨.     

产品概念设计中的相关技术

介绍了产品概念设计过程中功能设计和功能→结构映射的方法，对功能描述、功能定义库的建立、功能→结构映射的策略及其实现等技术问题进行了探讨，并以夹具设计为对象，对所述方法进行了论证。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with     

Journal of Donghua University ( English Edition) Contents of Volume 31

正~~