动力发生

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。

When parameters satisfy some assumptions, Rossler system is a chaotic dynamical system. In order to discuss the dynamical character of Rossler system and use delayed feedback control chaos, in the first, we discuss the stability of the steady states of Rossler system with delayed feedback. When the engenvalues of the linear part are pure imaginary numbers, we obtain the corresponding delay value. The stability of the steady state is lost when the delay passes through the critical value, and simultaneity chaos may vanish, as well as there will be a family periodic solutions bifurcate from the steady states.

在几个参数满足一定的假设条件下，Rossler系统是一个具有混沌特性的动力系统，为了研究该系统的动力学性质并利用时滞实现混沌控制，本文首先对具有时滞的Rossler系统的平衡点进行稳定性分析，当系统的线性部分对应的特征值为纯虚根时，算出相应的时滞τ，得到了平衡点的稳定性会在时滞τ取某些值时发生翻转，同时系统的混沌特性也会出现变化，并且在平衡点处系统经历Hopf分支。

During the four years study on the project, we develop a dynamical forecast model that describing the subtropical ridge surface. A new theory on the role of the land-sea thermal difference on the formation of the Subtropical High is advanced. It is concluded that in the summer subtropics over each continent and its adjacent ocean LO, SE, CO, and a double-dominant heating from west to east compose a LOSECOD heating quadruplet. The influence of the Eurasia continent on SH varies according to the seasonal variation. From the ideal numerical simulation it is shown the important role of the Eaiuan continent and the huge topography on the mechanism of formation and mantanence of the SH during the summer. It is verified by the numerical simulation that the extension of the subtropical continent into the tropics greatly enhances the " East Asian monsoon". Through the Rossby energy dissipation theory it is verified that the deep latent convective heating induces the onset of the South China Sea monsoon over the Bay of Bengal. The relationship and mechanism between the precipitaiton over the East Asia and the Subtropicla high is illustrated by the data. It is also found the close phase lock between the east-west shift of the SH and the disturbence of the east wind belt over the tropical troposphere. The interaction between the structure and activity feature of the SH and the Meiyu over the Yangtze-Huaihe river valley is revealed from the data. The numerical simulation verified the impact of the different SH pattern on the path of the typhoon.

本项目的研究发展了描述副热带高压脊面变化的动力模型，提出了夏季副热带地区四叶型非绝热加热分布型及相应环流拼图的创新理论；明确了大陆尺度的海陆热力差异在副热带高压形成中的作用；指出欧亚地形对副热带高压和气候的影响随季节变化而变化，通过数值试验证明春季青藏高原的感热加热对亚洲夏季风的爆发地点起了"锚定"的作用，进一步证实了副热带高压断裂和亚洲夏季风的最早爆发地点发生在孟加拉湾东岸；利用Rossby波能量频散理论证明了孟加拉湾深对流潜热释放诱导南海季风爆发的机制；揭示了东亚季风降水的季节内变化与西太副高的关系及机理；揭示了西太副高与东西风带中扰动之间的相互作用过程，指出西太副高的东西活动与热带对流层上空东风带扰动和中纬度西风带扰动的移动和锁相密切相关；研究了夏季淮河流域梅雨期间副高结构和活动特征及其与江淮暴雨的相互作用；验证了不同副热带高压形态对台风路径的不同影响；通过数值试验证明了欧亚大陆和青藏高原等大地形对副热带高压形成和维持的重要作用。

In order to investigate the excitation mechanism and response characteristics of wind-rain induced vibration of stay cable,an instrumentation system of wind-rain induced vibration measurement,which consists of anemometer,rain gauge and accelerometer,was installed on the Dongting Lake Bridge,Yueyang,China.

为了研究斜拉桥拉索风雨振的机理及响应特征，在岳阳洞庭湖大桥建立了由风速仪、雨量计、加速度传感器组成的风雨振现场观测系统，观测到了多次拉索风雨振现象；得到了发生拉索风雨振时风速、风向及雨量的基本条件，分析了风雨振时拉索振动的幅值、主振频率、模态参与特性及空气动力负阻尼比等响应特征。

Outsourcing is one of the most effective way in the new theory wind of enterprise remanufacture in the recent 10 years.At the same time,it is also one of the most important power that causes the world enterprise get radically changed,and it is one kind of important strategy to help the enterprise gain competitive advantage.

外包可以说是近10年来国内外兴起的企业改制的新理论之风中最有成效的方式，也是最近10年使世界企业发生根本变化的最重要的动力之一，是企业获取竞争优势的一种重要战略。

Sank? I have, and it's motivation enough to ensure it never

我有，而且这就是促使我不让这种情况再次发生的强大动力。

A diagonal pull tipping-bucket self-recording flow meter based on volumetric method is introduced herein; which consists of tipping-bucket flow sensor, mechanical pulse generator and counter; of which the innovation is that the engine counter used commonly in the weaving industry is successfully applied in the flow measuring through the design of a new mechanical pulse generator .

介绍了一种基于翻斗法量水的自记流量测定仪，该测定仪构成主要包括翻斗式流量传感器、机械脉冲发生器和计数器3部分，其创新点在于，通过自行设计的新型机械脉冲发生装置，将在纺织行业普遍应用的机械式累计数器成功的应用于流量的测定中，该测定仪最大的特点是无需任何动力，抗干扰能力强，特别适合野外工作

Thus, the design result is very important and has the great impact on ship-building.

因此，作为动力装置主体的舟舶主推入体系，其设计结果必对舟舶的整体机能发生重大的影响。

The 135 series of internal combustion engine unit are used as the major power devices for our national signal corps. Once fault occurs, it will impair the communication between armies, resulting in potential grievous losses.

作为我国陆军通信兵种主要动力设备的135系列内燃机组，一旦发生故障将严重影响我军的通信联络，造成不可估量的重大损失。

The nature of human was the summation of social relation.

交往是人的社会化的桥梁，是人的认识发生的源泉和发展的动力之一。

With Death guitarist Schuldiner adopting vocal duties, the band made a major impact on the scene.

随着死亡的吉他手Schuldiner接受主唱的职务，乐队在现实中树立了重要的影响。

But he could still end up breakfasting on Swiss-government issue muesli because all six are accused of nicking around 45 million pounds they should have paid to FIFA.

不过他最后仍有可能沦为瑞士政府&议事餐桌&上的一道早餐，因为这所有六个人都被指控把本应支付给国际足联的大约4500万英镑骗了个精光。