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In this topic, the dynamic analysis methods for piezoelectric vibrator are studied systematically based on the theoretical model, FEM numerical experimentation and FEM governing equation for given compound-mode vibrator, and some valuable conclusions are obtained. The main work accomplished is summarized as follows: 1.Elaborate the main modeling methods for piezoelectric vibrator and the significance and necessity to study the dynamic characteristics of piezoelectric vibrator which emphasize the urgency of this paper. 2.Take the bending deformation induced by piezoelectric ceramic as example, the energy transfer mechanism of electric energy to mechanical energy are analyzed; the motion and force transfer mechanism are analyzed for the longitudinal-bending vibrator. 3.Based on mode assumption and Hamilton principle, the coupling model of piezoelectric vibrator of linear USM is built; moreover, the equivalent circuit model is obtained and a coupling equation represents the relation between electric parameters and mechanical parameters is derived which provides foundation to match the vibrator and driving circuit. 4.Combine the constitutive equation of piezoelectric ceramic with elastic-dynamical equation, geometric equation in force field and the Maxwell equation in electric field and the corresponding boundary condition equation, the FEM control equation for piezoelectric vibrator of USM to solve dynamic electro-mechanical coupling field is established by employing the principle of virtual displacement. The equation lays the foundation to study the non-linear constitutive equation of piezoelectric ceramic driven by high-power. 5.Define the dynamic indexes of characteristic of vibrator and carry out variable parameters simulation by calculating the model parameters and the electric characteristics of vibrator are simulated according to the equivalent circuit model. By numerical experimentation, the working mode of vibration of vibrator and the shock excitation results of the working frequency band which provides the mode frequency to realize bimodal are analyzed. Detailed calculation of the electro-mechanical coupling field parameters is made by programming the FEM control equation.

本课题从理论模型、有限元数值试验、有限元控制模型等方面以复合振动模式振子为例对超声电机压电振子的动力学特性及其分析方法进行了全面系统地研究，得出了许多有价值的结论，主要概括如下： 1、阐述了目前针对超声电机压电振子的主要建模方法，对压电振子动态特性的研究意义和必要性进行了论述，突出了本文研究内容的迫切性； 2、以压电陶瓷诱发弹性体发生弯曲变形为例，分析了压电陶瓷通过诱发应变来实现机电能量转换的机理；对基于纵弯模式的压电振子的运动及动力传递机理进行了分析； 3、基于模态假定，利用分析动力学的Hamilton原理，建立了面向直线超声电机压电振子的机电耦合动力学模型，并据此建立了压电振子的等效电路模型，导出了电参量与动力学特性参量的耦合方程，为压电振子与驱动电路的匹配提供了依据； 4、从压电陶瓷的本构方程出发，综合力场的弹性动力学方程、几何方程、电场的麦克斯韦方程以及相应的边界条件方程，采用虚位移原理，建立了压电振子动态问题机电耦合场求解的有限元控制方程，为研究其大功率驱动下的非线性本构模型奠定了基础； 5、界定压电振子的动力学特性指标，对压电振子的机电耦合动力学模型参数进行计算及变参数仿真；依据等效电路模型，对压电振子的电学特性进行了仿真分析；通过有限元数值实验，对压电振子工作模态附近的模态振型及工作频率附近的频段进行了激振效果分析，找出了实现模态简并的激振频率；利用有限元控制方程，通过编程计算，对压电振子的力电耦合场参数进行了详细计算，得出了一些有价值的结论。

The prodrome of this paper includes main topics, research purpose, researching range and current situation about the relevant research in China and abroad, and the main methods the paper adopted.

在论文的序论中，介绍了论文的主题和研究目的，论文的研究范围，国内外相关领域的研究现状，以及论文研究采用的主要研究方式。

According to the learning of the Power l Supplying Projet, the primary design is about the 10kv switch-substation, according to the load and demand of the supply electric system of factory, the design of the gather reduction voltage substation and distribution system, and the checking of the main electric apparatus, the protection and adjusting and the lightning protection of the main voltage changer and line.

本文通过对供电工程的学习，主要是针对10kV开闭所进行初步设计。根据所提供的负荷及对供配电系统的要求，对主要设备进行选型校验，对主变压器、线路进行保护整定计算，对主、变线路进行防雷保护等。

In main stress trace protraction , based on the character of main stress trace , propose an automatic method

研究了一种简便快速的主应力迹线自动化绘制方法。

Studying pests of Gold-Autumn Pear in Da-long Country Long-tian Local Government in Hong-jiang City from February 2003 to October 2004, we primarily think Gold-Autumn Pears diseases include Gymnosporangium haracanumsyd, Venturia Pirina Aderh, Alternaria Kikuchiano Tanaka, Physalospora piricola Nose, and its insects include Psylla Pyrisuga Forst, Cinacium iakusuiensis kishida, Janus Piri Okamoto et Muramatsu,Toxoptera Piricola Mats, Urochela Luleovaria Distant, Eucleidae. Its main diseases are Gymnosporangium haracanumsyd, Venturia Pirina Aderh and Alternaria Kikuchiano Tanaka, main insects are Psylla Pyrisuga Forst, Cinacium iakusuiensis kishida.

通过2003年2月—2004年10月两年间在湖南省洪江市龙田乡大垅村对金秋梨病虫害防治的研究，初步确定了金秋梨上的病害有：梨锈病、梨黑星病、梨黑斑病、梨轮纹病，虫害有：梨木虱、梨黄粉蚜、梨茎蜂(Janus Piri Okamoto et Muramatsu)、梨星毛虫、梨二叉蚜Toxoptera Piricola Mats、梨蝽象(Urochela Luleovaria Distant、刺蛾等，其中以梨锈病、梨黑星病、梨黑斑病为主要病害，以梨木虱、梨黄粉蚜为主要虫害。

A pulsator for a washing machine is provided, which comprises: a main body installed on a bottom of the washing tub, and having a fan chamber and a upper surface formed with at least a spout outlet; a spout fan having a fan shaft and a plurality of fan blades extending radially from the fan shaft, the spout fan rotates relative to the main body to eject washing water upwards through the spout outlet; a bearing means for rotatably supporting the fan shaft in a radial direction as well as an axial direction; and means for rotating the spout fan.

一种洗衣机波轮，包括：一个安装在洗衣筒的底部的主体，具有叶轮室以及形成有至少一个喷水出口的上表面；一个具有叶轮轴和多个从叶轮轴沿径向延伸的扇叶的喷水叶轮，该喷水叶轮相对于主体旋转从而产生向上的洗涤水流；可在径向以及轴向上旋转支承叶轮轴的支承部件；以及使喷水叶轮旋转的部件。

The Paper include the following main points :(1) The paper proposed the academic background and significance of the topic and explained the BF raceway mechanism. The current situation and development trend of the field at home and abroad have done a review, and the main content of the paper have been proposed.

论文主要研究内容包括以下几部分：(1)首先提出了课题的学术背景及意义，阐明了高炉风口回旋区内的反应及形成机理，对相关领域的国内外研究现状以及发展趋势做了综述，并指出了本文的主要研究内容。

Main and slave rails are chose with high strength material. Its top and sides are all manufactured in very good surface. The precise rack is at main rail.

导轨采用高强度热处理加工路轨制作，导轨的顶面和侧面都经过精密机械磨削加工，在导轨外侧面装置精密齿条。

Finally we should note that main memory, magnetic disks, compact disks, and magnetic tape exhibit decreasing degrees of random access to data. The addressing system used in main memory allows rapid random access to individual bytes of data.

由此可知，主存储器，磁盘，光盘和磁带依次表示随机存取程度降低的设备，主存储器里所用的编址系统可允许快速随机地存取某个字节。

Now day's main competitions are the competition of technology and intelligence.But all these are attributed to the best use of its potential.Hence,how to realize this has become amajor subject.While the most complicated and difficult factor is how to encourage employees and give fuel play of their potentials.Since the policy of opening the country up to the world,the payment reform for the material promotion has been anot topic.But heather can give full play of the payment encouragement only on the basis of material promotion,which has ravishingly aroused people's consideration.However,no doubt,one of the main secrets for the sustainable development of an enterprise is to establish areasonable and effective payment system to basically ensure the sup erior competition of human resource and turn it into the advantage of market competition.

企业赖以生存和发展的基础可以概括为五种资源：资金、财产、技术、信息和人力，在这五种资源中，最重要的是人力资源当今的竞争主要是科技的竞争、智力的竞争，而这些归根结底都将是人力资源开发及其潜能充分利用的竞争所以，如何实现人力资源开发及其潜能的充分利用是企业公认的一大课题，而其中最为复杂和困难的，就是如何做好人员激励，使其潜能充分得到发挥改革开放以来，以提升物质利益为主题的薪酬改革一度成为了我国企业改革的暖门话题，而仅仅靠提升物质利益是否就可以充分发挥薪酬的激励作用也日益引起了人们的思考但不可否认企业能可持续发展的重要秘诀之一，应是建立合理有效的薪酬体系，从根本上保证人力资源的竞争优势，并将之转化为市场竞争的优势在本文中，笔者的主

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。