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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。

In the paper,the probability analysis method of the bearing capacity of cement deep mixing composite foundation is investigated,which will push the developing of the reliability design method of composite foundation.

文 摘 研究了水泥系深层搅拌桩复合地基承载力概率分析的方法，这对复合地基的可靠性设计将起着积极的推进作用。

The intraconjunction in date structure of DCO provides the theoretical foundation for parametrizing DCO and establishing the attribute relation of product component information, while the inter-hyperlink in information integration of DCO forms DC perception like Web browse and establishes the foundation of WWW pattern in engineering product information.

图元对象内部数据结构的关联性为参数化设计图元模型以及确立产品构件信息的属性联系提供了理论基础；图元对象外部信息集成的链接性形成了类似于Web浏览机制的图元感知模式，为工程产品信息的WWW实现模式奠定了基础。

Boyer, the former president of the Carnegie Foundation for the Advancement of Teaching published his famous report Scholarship Reconsidered: the Priorities of the Professoriate, and now it has developed intoa national movement with the Carnegie Foundation for the Advancement of Teaching, American Association of Higher Education and Indiana University-Bloomington taking the lead. What's more, it has had its influence beyond America to the countries like the U.K., Canada, Australia and Russia, etc., and become one of the important international movements of higher education in this era.

在1990年出版题为《学术的反思——教授的工作重点》的报告后，美国开始了长达10多年的对大学教学学术的大讨论，并形成了以卡内基促进教学基金会、美国高等教育协会及印第安那大学布卢明顿校区为主导的大学学术运动，其影响现已不仅限于美国，而且波及到了英国、加拿大、澳大利亚、俄罗斯等国，成为引人注目的当代国际高等教育的一种重要运动。

On this paper I will prove the conflicts between Protagoras and Socrates are based on the foundation of the different understanding for knowledge ; and discuss Protagoras" and Socrates"s Respective knowledge; Meanwhile take this as the foundation, carries on the appraisal to this conflict.

本文将论证普罗泰戈拉和苏格拉底的冲突是一场根基于对知识的不同理解而产生的冲突，对普罗泰戈拉和苏格拉底的知识进行清理；同时以此为基础，对这场冲突进行评价。

To finding out planning to build background and reason of the rock soil engineering specifications in the field, reconnoitre the rock soil projects of field and foundation, fully understand the project geological condition of building field and foundation, has combined testing, test testing and groundwater water analysis of normal position in the geotechnological sample room.

针对查明拟建场地岩土工程条件的背景和原因，进行场地与地基的岩土工程勘察，充分了解建筑场地与地基的工程地质条件，结合了土工试样室内试验、原位测试试验及地下水水质分析。

Designs a foundation information user-defined model and a report user-defined model according to students work manager's actual requirement,which is convenient to students work manager to manage foundation information data and to print a report by oneself.

根据学工管理人员的实际需求设计了基础信息自定义模型和报表自定义模型，该功能大大方便了学工管理人员对基础信息数据的管理，也可根据自己所需灵活地打印报表。

This essay has three difficulties: First, difficulty of conception foundation: how to grasp conception foundation, historical background and theory origin of positive economic paradigm and normative economic paradigm from a historical and philosophical perspective? Second, difficulty of formalization system: the viewpoints of positive economists and normative economists are very jumble, this paper tries to clear up the formers' theories, sums up and synthesizes various standpoints, and make it form systematism and standardization. Third, difficulty of combination in visual angle: combining economics and philosophy, resurvey some philosophy problems in economic research from the perspective of ontology, epistemology and methodology, thereby discover new problems, and make rigor argumentation toward it.

本文的难点：1、概念基础难点：如何从一种历史的、哲学的角度准确把握实证经济范式与规范经济范式的概念基础和变更的历史背景、理论渊源。2、形式化体系难点：实证经济学家与规范经济学家的观点非常混杂，本文试图理清前人的思路，总结和综合纷繁不一的观点，并使其体系化、规范化。3、视角结合点难点：将经济学与哲学有机地结合起来，从本体论、认识论、方法论的角度重新看待经济学研究中的一些哲学问题，从而发现新问题，并对其进行严密论证。

Then the foundation base is just like being "unloaded", its bearing load capacity is greatly improved. The rootstalk foundation is suitable and potential especially in deep coverage stratum .

由于根键与土体的紧密嵌固作用，使得基础的抗拔力不再是单纯的侧壁摩阻力，抗拔承载力也得以大大提高，尤其在厚覆盖地层。

Steel structure and concrete see an on the stage department take off to open completely, don't connect with each other with each other, presenting formally to round to match mutually, the foundation then sits on a foundation scaleboard for connecting with each other.

钢结构与混凝土看台上部完全脱开，互不相连，形式上呈相互围合，基础则坐在一个相连的基础底板上。

The witness also told the jury at the Royal Courts of Justice in London that he saw a paparazzo fighting with a member of the public who was trying to stop him taking pictures in the minutes before the emergency services arrived.

他还告诉在伦敦皇家法庭的陪审团，在急救服务到来之前，他当时看见一个狗仔队正和一群阻止他拍照的人打架。

The entire N／C program on a tape is made up of an accumulation of these successive data blocks.

纸带上的整个数控程序由这些连续数据单元连接而成。