查询词典 mechanical

The human heart is the center of the cardiovascular system. Integrated with mechanical, electrical, neural and biochemical properties, the heart is difficult to model, and there is no ideal integral model now. The developed electrical models haven't considered the mechanical properties and blood flow process in the heart; while the mechanical ones have normally deal with the heart in the diastole period, and the electrical activity was simplified too much although some mechanical models have investigated the heart during systole.

心脏是循环系统的核心，它集机、电、神经和生化控制于一体，建模难度很大，目前尚无较理想的统一模型；心脏电生理模型未与心脏的机械动力过程和血液流动过程联系起来；而心脏力学模型大都只研究舒张期的力学特性，即使研究收缩期心脏的力学问题，也往往对心电兴奋做了许多简化假设。

According to the past few years, we deal million Units Mechanical experience, the whole system approach has been striving to excel in our understanding of customers faced the common problem of mechanical and mechanical parts and additional parts of the function of interference after the treatment, we have developed a high standard of mechanical adjustment system of innovation.

根据数年来，我们处理万台机械的经验，整个系统方法已经精进，在我们了解顾客所面对的共同机件问题及械件机能干扰和额外部份处理之后，我们已经发展出具有高水准机械调整革新系统。

According to the past few years , we deal million mechanical experience, the whole system approach has been striving to excel in our understanding of customers faced the common problem of mechanical and mechanical parts and additional parts of the function of interference after the treatment, we have developed a high standard of mechanical innovations adjust system.

根据数年来，我们处理万台机械的经验，整个系统方法已经精进，在我们了解顾客所面对的共同机件问题及械件机能干扰和额外部份处理之后，我们已经发展出具有高水准机械调整革新系统。

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。

Through to pumps with the mechanical seal practical application and the theoretical analysis, proposed the mechanical seal actual seal effect not only with the mechanical seal own performance related, the condition which with other spare parts also which provides the condition as well as the seal servosystem provides to have the important relations, therefore pumps the unit product when the design, must for the mechanical seal use provide a good external condition.

通过对泵的机械密封实际应用和理论分析，提出了机械密封的实际密封效果不仅与机械密封本身的业绩有关的条件与其他零件也提供了条件以及印章伺服系统提供有重要关系，因此，泵的单位产品的设计时，必须对机械密封使用提供了一个良好的外部

The details of the research include: By studying the structure of the natural bamboo fiber, make the basic morphological structure and the degree of crystallization clear; By studying the mechanical property of the fiber, make the feature of mechanical property of the natural bamboo fiber clear; By studying the mechanical property of the pure yarn and its blends, make the feature of mechanical property of the yarn clear; and we also study the mechanical property changes of the pure yarn and its blends in the hygrometric state different temperature state and after mercerization and alkali shrinkage.

研究内容包括：通过对天然竹原纤维结构的研究，探明竹原纤维的基本形态特征和结晶度等特征；通过对天然竹原纤维机械性能的研究，探明竹原纤维的力学性能特点；通过对竹原纤维纯纺、混纺纱线力学性能研究，探明其纱线的力学性能特点；研究在湿态条件下，竹原纤维纯纺、混纺纱线力学性能的变化特点；研究在不同温度条件下，竹原纤维纯纺、混纺纱线力学性能的变化特点；研究在丝光、碱缩条件下，竹原纤维纯纺、混纺纱线力学性能的变化特点。

The welding nugget happened to dynamically recrystallize and the refined crystal grains were obtained and the majority of Mg_2Si particles dissoluted due to the intensive mechanical stir and higher high temperature. In the thermal-mechanical affect zone that was heated under the recrystallized temperature, the crystal grains were elongated due to the mechanical stir and Mg_2Si particles partly dissoluted and the others grew. In the heat affect heat without the mechanical stir, to some extent, both of the crystal grains and the majority of Mg_2Si particles grew.

焊核区受到强烈机械搅拌作用和加热到较高的温度发生动态再结晶，得到细小等轴晶组织，Mg_2Si相以溶解为主；热机影响区加热温度低于再结晶温度，在机械搅拌作用下晶粒由于塑性变形而伸长，Mg_2Si相部分溶解，部分长大；热影响区仅受加热影响，晶粒有一定程度长大，Mg_2Si相以长大为主。

In order to strengthen the management on old major mechanical and electrical product, old mechanical and electrical products (see the appendix for detailed catalogue) relating to production safety, personal safety (electric appliances, medical apparatus and instruments) and environmental protection (engineering and Vehicle and ship craft machinery), as well as those quota, specially designated, or unifiedly registered (including those old mechanical and electrical equipment provided by foreign investors in foreign investment and processing trade enterprises), shall be dealt with according to the Notice on Strengthening Management on Imported Old Mechanical and Electrical Products Guo Jing Mao Ji No.

一、为加强对重点旧机电产品的管理，对涉及生产安全、人身安全和环境保护的旧机电产品及配额、特定、集中登记的旧机电产品（包括外商投资和加工贸易企业由外商无偿提供进口的旧机电产品）仍按《关于加强旧机电产品进口管理的通知》（国经贸机〔1997〕877号）办理。

The classic macroscopic mechanical models, which characterize the concrete and granite as continuums at macroscopic level and consider the test results of laboratory scale specimen as the mechanical properties of the material, could analyze the mechanical response of structures with greater size. In reality, the test results of laboratory that are generally called physical and mechanical parameters of material are average responses of a heterogeneous specimen with a certain size.

有关混凝土和花岗岩力学特性的力学模型都是基于混凝土和花岗岩材料的宏观层次研究其力学特性，其主要特点是把材料理想化为均质材料进行研究，把实验室尺度下力学试验的结果作为材料的力学参数，以此为基础进行更大尺度宏观结构的力学响应分析。

Based on a leveling algorithm, the obliquity angle is converted to elongations of the mechanical supporting to drive the mechanical supporting to level the baseplane. The reasons for choosing three supporting points and mechanical supporting are introduced, then mechanical supportings and the entire transmission system are designed.

给出了支撑腿数量和机械式支腿的选择依据，设计了一种可以在小角度范围内自动矫正受力方向的机械支腿，设计了整个传动系统，并且给出了驱动电路和调平算法。

I can not make it blossom and suits me

我不能让树为我开花

When temperatures are above approximately 80 °C discolouration of the raceways or rolling elements is a frequent feature.

当温度高于 80 °C 左右时，滚道或滚动元件褪色是很常见的特征。