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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。

This proposal , which has success probability of unit , is mainly employing two atoms for receiving the teleported state, and a two- mode cavity as the quantum channel.

在这个方案里，我们主要利用两个原子用来接受被传送的原子纠缠态以及一个双模腔作为量子通道。

By employing the theory of ∑Γ－fuzzy truth degree, the concepts of Γ-pseudometric on F was proposed in the propositional logic system Ln. The results obtained can complement and enhance the original theory of metrology of logic, and can give a new frame for fuzzy reasoning study.

特别地证明了真度关系：τΓ+τΓ≤1+τΓ，并利用这一关系在模糊命题演算系统Ln中的公式集F上引入相对于有限理论的Γ-伪距离，从而为在模糊命题逻辑系统Ln中建立相对于有限理论的近似推理框架奠定了基础。

By employing the theory of ∑Γ－fuzzy truth degree, the concepts of Γ-pseudometric on F was proposed in the propositional logic system Ln.

特别地证明了真度关系：τΓ+τΓ≤1+τΓ，并利用这一关系在模糊命题演算系统Ln中的公式集F上引入相对于有限理论的Γ-伪距离，从而为在模糊命题逻辑系统Ln中建立相对于有限理论的近似推理框架奠定了基础。

It is indicated that employing the new oil pumping unit can raise the efficiency of the sucker rod pump under the surface.

分析与计算结果表明，新型液压抽油机的效率较常规游梁式抽油机的效率有较小幅度的提高，并指出了这种抽油机对提高井下效率的可能性。

In order to demonstrate the advantage of combined strategy, CFDAMA-WFA scheme which employing the pure Weighted Free Assignment strategy was presented.

仿真结果说明，CFDAMA-RPR协议与CFDAMA-PB、CFDAMA-RR、CFDAMA-CR协议比较，能实现更好的时延／吞吐量性能。

In the work, employing a function with four undetermined parameters to model the source wavelet, an analytical relation between Q-factor and envelope peak instantaneous frequency is derived from the theory of one-way waves propagating in an anelastic medium; at the same time, a method for extracting instantaneous frequency in wavelet domain is developed for improving the precision and anti-noise performance of IF estimation, and based on these, a method called EPIF in wavelet domain is proposed for estimating Q-factor of VSP data.

本文采用一个具有4个待定参数的函数去逼近震源子波，利用黏弹介质中单程波传播理论推导出了地震子波包络峰值处瞬时频率和品质因子之间的解析关系；同时，为提高瞬时频率的估计精度和抗噪性能，在小波域中发展了一种计算瞬时频率的方法，并在此基础上提出了估算VSP资料Q值的方法，简称小波域包络峰值处瞬时频率法。

This integration is performed in closed form by employing quadratic polynomial approximations for the amplitude and unwrapped phase of the integrated.

我们给出了电流近似和积分过程的举例。

We can realize completely efficiency ionization probability under the condition of low Rabi frequencies by employing lower power and time-delayed laser pulse.

采用两脉冲之间具有一定延迟的驱动和探测激光场，可以实现在较低Rabi频率情况下粒子的全部高效率电离。

The research results indicate that the distribution of engine work points is improved, the variation range of capacitor SOC is restrained and the response performance of the system is not affected when employing this control strategy.

研究结果表明，采用该控制策略后，改善了发动机工作点的分布区域，抑制了电容器SOC的变化幅度，且基本不影响系统的响应性能。

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。