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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 behaviors of the driven field and radio field are studied in this paper and it can be seen that the forming of EIA or EIT and the whole probing properties are controlled by the Rabi frequencies of both driven field and radio field.

本文对新引进的驱动场的作用规律进行了重点研究，研究结果表明，当驱动场和射频场的Rabi频率满足不同关系时，系统呈现EIA或EIT两种不同特性，探测吸收曲线的整体轮廓也随之改变。

Electromagnetics course mainly including basic phenomena and laws of electro- magnetics, electrostatic field in vacuum, in conductor and in electric medium, electric energy, stabilized current, stabilized magnetic field and its basic laws, electric and magnetic fields caused by a moving chager in lower speed, the transform of electric and magnetic fields between different systems of coordinates, inductive laws, eddy field, self inductance, mutual inductance and transient, molecule current and magnetic substance, ferromagnet, boundary conditions, magnetic circuit theorem, energy of magnetic field and density of magnetic energy, displacement current, Maxwell's equation, electromagnetic wave, Poynting vector.

电磁学课程的主要内容包括：静电的基本现象和基本定律，真空中的静电场，导体和电介质中的静电场，电场的能量与电场能量密度，稳恒电流，稳恒电流磁场的基本定律，运动电荷的电磁场，不同参照系之间电磁场的变换，电磁感应定律，涡旋电场，互感，自感，暂态过程，分子电流与磁介质，铁磁体，边界条件，磁路定理，磁场的能量和磁能密度，位移电流， Maxwell 方程组，电磁波和玻印廷矢量等。

Based on the aberration theory of AWG, a new-type flat-field AWG is designed. The focal signals of all wavelengths of operation are focusing along a straight line perpendicular to the propagation direction. Three stigmatic points restrain three dominant geometry parameters. Furthermore, a new-type flat-field wavelength router with both flat input field and flat focal field is also designed.

基于阵列波导光栅的像差理论，利用三个无像差点约束三个主要结构参量，设计了新型平场聚焦阵列波导光栅，使得所有工作波长的输出信号都聚焦在与光束传输方向垂直的直线上，并进一步将其拓展为同时具有平输入场和平聚焦场的新型平场波长路由器。

According to the similar nature of gravitational field and electrostatic field, using analogy method, the stress tensor in gravitational field is obtained from Maxwells stress tensor in electrostatic field, and the universal gravitation inside t

文摘：根据引力场和静电场的相似性质，通过类比方法由静电场的麦克斯韦应力张量得出了引力场中的应力张量，并用它计算了均质球体内部的万有引力。

According to the similar nature of gravitational field and electrostatic field, using analogy method, the stress tensor in gravitational field is obtained from Maxwells stress tensor in electrostatic field, and the universal gravitation inside the isotropic spheroid is calculated with the obtained result.

文摘：根据引力场和静电场的相似性质，通过类比方法由静电场的麦克斯韦应力张量得出了引力场中的应力张量，并用它计算了均质球体内部的万有引力。

That is, the appropriate electric field should be a uniform electric field in the strength of 1.0V/cm with the reversal time interval of 10 min in rhizosPHere soil; while the appropriate electric field should be a uniform electric field in the strength of 1.5V/cm in non-rhizosPHere soil.

施加均匀场1.0V/cm的同时，每隔10min切换极性，是土壤根际微生物群落在电场作用下比较合适的电场条件；而对土壤非根际微生物来说，施加均匀场1.5v/cm是相对比较合适的电场条件。

In order to explore the effect on DNA synthesis and DNA double-strand breaks by magnetic field, We chose a relatively simple uniform magnetic field, study the affect on DNA synthesis and DNA double-strand breaks by such magnetic field, conclused that this impact related to magnetic field strength.

为了研究磁场对DNA的合成速度和DNA双链断裂的影响，我们选择比较简单的均匀磁场，从理论上探讨了此种磁场对DNA合成速度和DNA断链的影响，得到其合成速度改变和双链断裂程度与磁场强度大小有关。

Load or create object from "name" field, save to local call Name unmarshalling method store reference from local variable to "name" field unmarshal "street1" field value from "street" element unmarshal "city" field value from "city" element ...

清单 4 为图 2 的左下部分给出了实现从 XML 到 Java 对象的解编排所需的抽象操作列表。清单的顶端部分完成的是一个 Customer 实例的解编排，底部完成的是一个 Name 实例的解编排。

Here we have discussed the Casimir force of Maxwell-Chern-Simons gauge field and obtained the new results, namely the contribution of force of M-C-S gauge field to the Casimir force zero temperature, the radiative correction to the Casimir force of M-C-S gauge field at zero temperature and Casimir force of M-C-S gauge field at finite temperature between two parallel ideal conducting wires.

本文讨论了两个平行的，理想的金属线之间Maxwell-Chern-Simons规范场的Casimir效应。不仅得到了绝对温度下自由的M-C-S规范场对Casimir力的贡献，而且得到绝对温度下M-C-S规范场的真空涨落对Casimir力的辐射修正以及温度对M-C-S规范场的Casimir力的修正，并且分别考虑了无质量极限，低质量极限和高质量极限情况。

Methods Clinical data of 3 cases of bile duct injury during laparoscopic cholecystectomy were analyzed retrospectively.

回顾总结3例LC术中胆管损伤的临床资料，分析3例胆管损伤的原因及对策。

These techniques are applied to the gobang.

本文将这些技术用于五子棋中。