Thermal Effect Mechanism and Surface Topography of the Micro-EDM Workpiece

微细电火花加工具有可以非接触加工、三维加工能力以及设备简单、可实施性强、加工性能与材料硬度强度无关等优点。这种方法能加工处理的材料非常广泛，不仅可以加工各种性能优良的金属、合金，还可以加工陶瓷、硅等半导体材料。因此，微细电火花加工在复杂微小零件的制作中有着独特的优越性，也得到了广泛的应用。目前，微细电火花加工的理论研究和工艺研究还存在很多问题，尤其在蚀除过程中，现在普遍采用普通电火花的加工机理来说明。微细电火花加工具有放电时间短、放电通道半径小及能量密度高等特点，所以其放电过程与普通电火花明显不同。因此，本文按照微细电火花加工蚀除过程和表面成形的先后顺序，对微细电火花窄脉宽放电加工的热源模型、...Micro-EDM(Electric Discharge Machining) has brilliant advantags in non-contact processing, 3-D machining ability as well as the equipment is simple, practical strong, processing performance has nothing to do with the material hardness, strength, etc. This method has a very wide range of materials’ processing ability, not only can process various metals and alloys with excellent properties, but als...学位：工学博士院系专业：物理与机电工程学院_机械电子工程学号：1992011015403

WTO的知识产权保护体制及其影响

随着世界经济的增长与知识产权有关的贸易在国际贸易中所占的地位越来越为重要与知 识产权有关的贸易的主要出口方是发达国家其国内的知识产权保护制度起步得早制度发 展较为完善而该类产品的主要进口国为广大的发展中国家其知识产权保护立法起步晚 发展也不够迅速因而对知识产权保护不够全面或者极少存在着保互另外发展中国家由 于自身资金技术缺乏宁愿对知识产权采取弱保护的态度与政策以便使本国尽量以较低的 成本获得更多的技术这种情况造成了国际间知识产权侵权现象大量存在发达国家认为自 身由此遭受了巨大的经济损失对现有的知识产权国际保护体制也极为不满要求将该问题 纳入对世界贸易影响最大的关税与贸易总协定来解...学位：经济学硕士院系专业：经济学院国际贸易系_国际贸易学学号：19951304

Improve Efficiency of Motor Measures

在能源日趋紧张的情况下,如何提高效率,节约能源逐渐成了社会普遍关心的问题。根据电动机的结构特点、电磁优化和工艺等方面,分析了如何提高电动机工作效率,从而达到节省能源的目的。In an increasingly tense energy,How to improve the efficiency,save energy gradually became a universal concern.In this paper,according to the structure characteristics of the motor,electromagnetic optimization and process and so on,and analyzes how to improve work efficiency motor,so as to achieve the purpose of saving energy

现阶段个人所得税的主要政策目标及其实现

个人所得税作为税制体系中的一个重要税种，在实现收入、效率和公平目标上均可发挥作用。在不同时期及不同的政治经济背景下，个人所得税政策目标的侧重点是不同的。在现阶段我国市场经济快速发展，而居民收入差距逐步扩大的情况下，调节过高收入，缩小收入差距，即实施纵..

Fuzzy Sliding Mode Speed Control System of Permanent Magnet Linear Synchronous Motor Based on Saturation Function

针对永磁同步直线电动机,介绍了其数学模型,建立了直线电机闭环控制系统,该控制系统速度环采用基于指数趋近率的模糊滑模控制,电流环采用传统的PI控制。并利用MATlAb仿真软件建立了基于饱和函数的永磁同步直线电机调速系统模糊滑模控制的仿真模型。仿真结果表明,模糊滑模控制有效地削弱了抖振,系统动静态性能良好。This article in view of permanent magnet linear synchronous motor,introduced mathematical model,established linear motor closed-loop control system,the control system speed loop adopt fuzzy sliding mode control based on exponential approach law,current loop adopt traditional PI control.And constructed simulation model of fuzzy sliding mode control of permanent magnet linear synchronous motor speed control system based on saturation function by matlab simulation software.The simulation results show that fuzzy sliding mode control is effective to weaken chattering,the system dynamic and static performance is good

Study of Control System of Permanent Magnet Linear Synchronous Motor

介绍了永磁同步直线电机技术、应用范围和直线电机的类型及选型,分析了直线电机伺服控制系统的多种控制方法存在的利弊,为直线电机的高精度控制的实现提供帮助。This paper introduces technology,the application range and the type of the permanent magnet synchronous linear motor, analyzes the advantages and disadvantages of various control methods in linear motor servo control system, offers help for implementation of high precision control of the linear motor.黔科合J字LKS(2013)33

Study on Expansion of Micro-EDM Discharge Channel

为了模拟微细电火花放电通道扩展的过程,对放电等离子体通道进行了深入研究,建立了一个适用于微细电火花放电加工的等离子体扩展模型。基于介质击穿机理和磁流体力学的相关知识,模型综合考虑了等离子体扩展过程中的粘性力、表面张力及磁场箍缩力等各个作用力,使扩展过程更接近于真实。最后,通过比较微细电火花rC单脉冲放电的模型计算直径与实际加工直径,验证了等离子体扩展模型的正确性。To simulate the process of micro-EDM discharge channel expansion,discharge plasma channel has been studied.A suitable plasma expansion model of micro-EDM has been established.Based on the dielectric breakdown mechanism and relevant knowledge of MHD,the various forces such as viscous force,surface tension and magnetic pinch force,in the process of plasma expansion has been considered,which makes the expansion process closer to the real.Finally,comparing the calculation diameter of micro-EDM RC single pulse discharge model with the actual machining diameter,the correctness of plasma expansion model is verified

The single pulse thermal effect mechanism of micro-EDM

为了解微能量单脉冲放电加工原理,文中从微细电火花单脉冲放电加工具有放电时间短,放电通道半径小,能量密度高等特点入手,从单脉冲热作用模型的放电通道半径和能量分配系数方面对当前电火花单脉冲蚀出模型进行改进。建立了时变放电通道的热作用模型,并验证了模型的正确性,提出了单脉冲热作用模型中能量分配到工件表面的百分比系数随着放电参数的变化而变化的规律,为微细电火花的广泛应用奠定基础。The single pulse micro electric discharge machining( micro-EDM) has the characteristics of short discharge time,small discharge channel radius,high energy density,etc. Considering these characteristics,the EDM single pulse erosion model is improved in plasma channel radius and energy distribution coefficient of the single pulse thermal effect model,to establish the thermal effect model of micro-EDM machining. The correctness of the model is verified by a reliable experimental method,which lays a foundation for the wide application of micro-EDM.贵州省教育厅基金项目(5392

Fast 3-D surface information acquisition based on smart camera

为了大幅度提高三维信息获取速度,提出了一种基于智能相机和激光三角法的高速三维信息获取与表面重建的系统,介绍了该系统的硬件架构和信号处理。实验结果表明,采用数字信号处理器和并行处理方式,该系统获取三维表面信息速度可达5600点/s以上。Acquiring 3-D surface information by means of laser triangulation is a kind of active vision measurement.In order to improve the measurement speed,a fast 3-D information acquisition and surface reconstruction system based on smart camera and laser triangulation was presented.The hardware construction and data processing flow of the system was introduced.Because of applying of the digital signal processor(DSP) and parallel processing,the result of experiment shows that the speed of acquisition can reach 5600 dots/s.国家自然科学基金资助项目(60375011);; 安徽省自然科学优秀青年科技基金资助项目(04042044);; 国家自然科学基金国际合作项目(2005年度中德合作PPP基金资助项目60416312);; 新世纪优秀人才支持计划资助项目(NCET-04-0560