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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 paper investigates the several key problems in calculating reliablity with direct numerical integration and completes a direct numerical integration program, and conducts some parameter analyses.

在计算过程中发现JC法在计算一些比较复杂的结构问题时有一定的局限性，特别是在计算非线性的极限状态方程和解决多模态相关问题的可靠性时，存在着较大的误差。

One of the most fundamental concepts in the area of advanced manufacturing technologies is numerical control Controlling a machine tool using a punched tape or stored program is known as numerical control.

在先进制造技术领域的最根本的观念之一是数控机床控制用穿孔纸带或存储方案被称为数控的。

In order to control the propagation of errors and enhance the accuracy of numerical solution, the wilson-θ method is modified and the numerical stability of modified wilson-θ method is analyzed.

为有效控制误差的传递，提高计算精度，对Wilson-θ法进行改进并分析了改进Wilson-θ法的稳定性。

On the basis of the casing damage mechanism study,the fluid pressure field numerical modeling and finite element numerical modeling under solid mechanical propertied and fluid-solid coupling conditions were introduced.

并进行了大量的现场测试，获取了大量准确的资料，为深化套损机理研究奠定了基础和提拱了支撑；五是开展了大量的室内和现场试验。

Therefore, it is always reasonable that the numerical rank be regarded as the rank of a matrix in the process of numerical computations.

从而在数值计算过程中，认为矩阵的秩就是其数值秩总是合理的。

Do some tentative analysis of the tunnel lining by numerical manifold method. the idea is given that combining regular mesh with finite element mesh and using low-order and high-order cover displacement function in numerical manifold method, it make preprocess and program analysis, precision and efficiency for coordination.

4利用数值流形方法对隧道工程中衬砌结构进行了尝试性的分析，提出了结合规则网格和有限网格并行、高低阶覆盖位移函数混合计算的思想，以达到前处理和程序计算、计算效率和求解精度的协调。

In order to study initial stress and ring force transfer between steel plates and concrete in the numerical analysis of RC beam strengthened by bonding steel plates,8 scale-down models of RC beam were manufactured,their loaded whole processes were analyzed by using surface-surface contact analysis method and "birth and death" element method,and a numerical analysis method of strengthening RC beam with initial stress was proposed.

0引言钢板加固钢筋混凝土结构已在国内外受到广泛应用和研究，并且已获得了大量的研究成果，但成果主要来源于室内模型试验。由于受到试验规模的制约，目前所取得的研究成果，特别是试验成果还带有较大的片面性，不能系统地反应其真实的自然规律[1-3]。

The mechanical behavior of Shape Memory Alloys material is tested, and the constitutive model of the SMA is established. A kind of SMA combined rubber isolator is developed, and the isolation effect of the SMA combined rubber isolator for long-span bridge and tall building structures is numerically simulated, from which the adaptive isolation performance and the self-restoring capacity of the SMA combined rubber isolator are verified. A kind of SMA damper is developed, the mechanical behavior of the SMA damper is tested, and the model of restoring force of the SMA damper is established. The theory and method of adaptive control based on the SMA damper for the long-span bridge are built, and the effectiveness and reliability of the adaptive control for the long-span bridge using the SMA damper are verified through numerical simulation and model test. The MRF-04K type magnetorheological damper is developed, the mechanical behavior of the MR damper is tested, and the model of restoring force of the MR damper is established. The theory and method of adaptive control based on the MR damper for the long-span bridge and tall building structures are built, and the effectiveness and reliability of the adaptive control for the long-span bridge and tall building structures using the MR damper are verified through numerical simulation and model test. In addition, the theory and method of sub-structural damage identification for long-span bridge are derived, the influence of soil-structure dynamic interaction on the seismic isolation and control effects with different isolation and control measures and the damage responses and the sliding base-isolation of large structures under the excitation of underground explosion are investigated.

试验研究了形状记忆合金材料的力学性能，建立了SMA材料的本构模型；研制了一种SMA复合橡胶隔震支座，数值仿真分析了应用SMA复合橡胶支座的大跨桥梁和高层建筑结构的隔震效果，从而验证了SMA复合橡胶支座的自适应隔震性能及其震后自恢复能力；研制了一种SMA阻尼器，试验研究了SMA阻尼器的力学性能，建立了SMA阻尼器的恢复力模型，建立了基于SMA阻尼器的大跨桥梁结构自适应控制理论与方法，通过数值仿真与模型试验验证了大跨桥梁结构SMA阻尼器自适应控制的有效性与可靠性；研制了一种MRF-04K型磁流变阻尼器，试验研究了MR阻尼器的力学性能，建立了MR阻尼器的恢复力模型，建立了基于MR阻尼器的大跨桥梁和高层建筑结构的自适应控制理论与方法，通过数值仿真和模型试验验证了大跨桥梁和高层建筑结构MR阻尼器自适应控制的有效性与可靠性；还建立了大跨桥梁结构的子结构损伤识别的理论与方法，研究了土-结构动力相互作用对不同隔震和控制措施的减震控制效果的影响以及地下爆炸波作用下各类大型结构的灾害响应与滑移隔震。

Numerical calculations were accomplished by the directly numerical method of the singular integral equations and a large amount of statistical results were obtained. So the issue of influence was systematically solved.

最后利用奇异积分方程的数值解法进行了数值计算，得到了大量的数值结果，从而系统地解决了一般倾斜裂纹对界面的影响分析。

In the days of sailing vessels the crew were afraid they would be becalmed on the ocean.

在使用帆船的时代，船员们担心他们会因为无风而无法在海洋上航行。

As long as foreign donors pay the PA's salary bill, few expect a new intifada.

只要外国继续为巴权力机构的薪水买单，希望发动新暴动的人便寥寥无几。