查询词典 mode of vibration

Using the models, the author has also calculated the vibration response to high speed railway vehicles of three types travelling over simply-supported beam bridges with various span lengths respectively. Based on the analysis of the computation results, the concept of resonance velocity of a bridge under a high speed running vehicle is present, and it is pointed out that comparatively great vibration of bridges on high speed railways is caused by bridge resonance resulted from the static force pulsating. In a vehiclebridge coupling vibration system, the damping constant of the axle spring is the main factor affecting the response variable of bridge velocity resonance, and the influence of track irregularity on bridge vibration on high speed railways is rather smaller.

利用所建立的计算模型，计算了三种形式的高速铁路车辆通过各种跨度简支梁桥结构时的振动响应，对所得到的计算结果进行了详细的分析，提出了高速行车下桥梁共振速度的概念并指出高速铁路桥梁产生较大振动的原因是静力脉动引起桥梁共振造成的；通过研究车—桥耦合振动系统方程的参数后指出，在车—桥耦合振动系统中，车辆—系阻尼的大小是影响桥梁速度共振时响应大小的主要因素，轨道不平顺对高速铁路桥梁振动的影响较小。

Electric massager high frequency due to vibration, vibration strength is weak, more suitable for the elderly in the use of massage and health care; and electromagnetic vibration frequencies due to slow massage, vibration strength is higher and thus more suitable for sports massage and young people.

电动按摩器，由于高频振动，振动强度较弱，更多的在按摩和保健使用适合老人和电磁振动频率由于缓慢按摩，振动强度较高，因此更多的运动按摩和青年合适的人。

ObjectiveTo observe the effect of vibration massage apparatus on skin temperature by infrared thermal imaging system .Methods30 healthy students of Shanghai university of TCM accepted two operations of vibration massage apparatus-non-vibration and vibration . The temperature diversity was obseved at different time : before operation , after 3min operation, after evaluating apparatus 1, 2, 3,4,5 min by infrared thermal imaging system .

方法上海中医药大学的30名健康大学生先后接受机械振动按摩器的空置和振动两种操作，用红外热像仪分别于操作前0 s、操作3 min后即刻、撤离仪器后1 ，2，3，4 min和5 min观察受试者以心俞为中心的手掌大小区域的温度的动态变化，并用分析软件处理相关温度数值，将结果进行统计学分析。

Guangxi Yantan turbine diameter 8m 90s in the 20th century in operation, mainly due to the hydraulic design and manufacturing quality Runner and other reasons, put into operation a serious vibration, cracks, vibration tube into the door crack, power generation Floor Vibration machine layer. 10 years of annual repair cracks, cavitation, multiple blade line has been restored can not be guaranteed, for the more radical change in this situation, has on one desktop PC upgrades, replacement of the old wheel, replaced by a Taiwan new designs, new technology a new wheel, troubled years of generating station floor floor vibration problems are basically solved.

广西岩滩水电站直径达8m的水轮机在20世纪90年代投入运行，主要是由于水力设计和分瓣转轮制造质量等原因，投入运行后振动严重，裂纹产生，尾水管进入门振裂，发电机层楼板振动。10年来年年修补裂纹、空蚀、多次修复后叶片型线已无法保证，为较彻底的改变这种状况，已对其中一台机进行升级改造，更换了老转轮，代之以一台新设计、采用新工艺的新转轮，困扰电站多年的发电机层楼板振动问题得到基本解决。

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 this part, the characteristics of transient responses of flexible rotor systems with arbitrarily distributed mass on isotropic or anisotropic supports passing through several critical speeds seguencially are examined. Here, the current knowledge of rotor dynamics on the eigenproblem of damped free whirling vibration, the generaliged damped mode theary, the transient forced vibration and so on combined with KBM asymptotic method in the nonlinear vibration theory is employed and extended.

作者综合运用并引伸推广转子动力学关于阻尼自由回旋振动的特征问题、广义阻尼模态理论、瞬态强廹振动等現代理论和方法，结合非线性振动理论中的KBM渐近法，提出自己独創見解和覌点，成功地建立起正回旋和逆回旋两种情况下转子通过临界点的瞬态振动一阶微分方程组，可以在临界点的邻域内从事方程的数值积分计算。

Vibration model is established and inherency frequency and main vibration type are obtained, vibration characteristic response is analyzed. Mode respond and harmonious respond of suspension system with package cushioning are analyzed with the help of ANSYS 6.0. At last, design method of suspension system with package cushioning is researched and a detailed design example is provided.

第三，介绍了弹簧吊装系统的振动分析理论，建立了振动模型，得到了系统的固有频率及主振型，分析了系统的振动响应；并利用ANSYS6.0有限元分析软件对悬浮式缓冲包装模型进行了模态分析和谐响应分析。

In the past, the high frequency resonance technique is usually applied in the envelope detection for a vibration signal with amplitude modulation. When applying the Hilbert transform in the high frequency resonance technique for the envelope detection of vibration signals, the computing burden is very high. On the other hand, when applying the linear least squares analysis method, the computing burden is lower. When applying the envelope detection in the lowest vibration mode, an accelerometer with the low-pass filtering cutoff frequency at 4kHz should be choose.

在过去的研究方法中，振动讯号之振幅调变通常以高频解调分析法应用於包络讯号侦测，而高频解调方法应用希尔伯特转换的包络分析，所需要的计算量是非常的高，若以线性最小平方分析法应用於高频解调分析法中，则所需要的计算量较小，如果以最低模态来估测包络讯号时，可以适当的选取加速规来代替低通滤波器，而加速规的截止频带必须在4kHz左右。

The free vibration of a nonlinear elastic rectangular plate is explored, considering influence of material nonlinearity and static-load in plane on its dynamic characteristics. Exact solution to free vibration of each mode of the rectangular plate is obtained according to the fixed point theory of partially ordered space. So the whole process of free vibration is described.

对非线性弹性矩形板的自由振动进行了研究，考虑了材料非线性和面内静载对板动力特性的影响，并根据半序空间的不动点理论求得该矩形板在自由振动时各阶模态的精确解，描绘了其自由振动的全过程。

For vibration mode-shape, this affect is moreseverity on high rank stage vibration than low. With opened hollow and pier added on dam,the frequency of vibration decline.

对于振型而言，这种影响对低阶振型比高阶振型大，考虑孔口和闸墩后，大坝的自振频率有所降低；在低阶振型中有一部分的排列顺序发生了变化，但这些变化不致使大坝的动力特性发生显著的改变。

Now she was hungry and angry.She began to smoulder.

现在她又饿又气，她开始流露难以抑制的怒火。

You have placed our iniquities before You, Our secret sins in the light of Your presence.

诗90：8 你将我们的罪孽摆在你面前、将我们的隐恶摆在你面光之中。