振动性的

The thesis discusses three eigenvalues individually and explains the pressure wave propagation of three modes, includes wave speed, wave decay and energy distribution. Since the elastic potential energy occupies more than 98% of mechanical energy in the arteries, which is larger than 2% of kinetic energy of flowing blood. Else join elastic wall and wall of managing having a viscid condition to analysis .

本文将个别讨论此三组特徵值，来说明三组压力波的传递模态，其中包括波速，以及波的衰减；由於在动脉的能量分布中，由管壁振动的弹性位能占了98%，远超过血液本身流动的2%，再加上管的弹性模数和管壁的黏滞性再来讨论此三组模态，个别在弹性管的能量分布。

Pointing at the problem that the effectiveness of learning control is influenced by the unrepeated disturbances, three types of repetition learning hybrid control concerned with fricitions are proposed, and their convergence is proven.

实验和FFT的分析结果表明，本文提出的四种控制方法均增强了控制系统的稳定性，提高了控制精度和平滑性，特别是在消除装配中的振动和阻塞现象方面是非常有效的。

Therefore, for improving the accuracy of exceed slender axle on turning,must need to do with the lathe fixture and cutting tool for further improvement. In order to reached the requirements of precision machining,in machining process must use follower rest、flexible active thimble、space block and bracket etc fixture and assistive device.

超细长轴在车削加工中承受自身重力、切削力、高速旋转产生的离心力的作用，极容易出现振动与弯曲变形现象，增大轴的几何形状误差，而超细长轴的轴向尺寸较大，直径较小，热扩散性及刚性差，受切削热作用会在轴向发生线性膨胀，若在轴向的伸长量无法得到消除，轴将受迫弯曲，从而影响轴的精度。

Be living in the deep well ultradeep well prospecting process ,Since radial direction force 、Eddy is stird 、Elements such as horizontal vibration and so on being ,In the wake of well drilling time the increase ,The auger post writings is used the casing inside wall crossrange strenuously to broaden ,It is more and more grave to cause casing and drilling rig to join the wornout problem .

论文摘要：在深井超深井勘探过程中，由于径向力、涡动、横向振动等因素的存在，随着钻井时间的增长，钻柱作用于套管内壁的侧向力增大，导致套管和钻具接头磨损的问题越来越严重。造成钻具耐磨带失效的主要原因有地层研磨性、钻杆的井下工况、耐磨材料选择与

Firstly, based on the sliding mode control and backstepping technique, a new attitude tracking controller is derived to control the attitude motion of spacecraft, the stability of the system is analyzed via Lyapunov method and the reaction wheel dynamics is also considered from the real applications point of view. The whole design process is divided into two steps: the first step is to use sliding control technique to design suppositional adaptive variable structure controller; and the second step is to design attitude tracking controller based on SMC and backstepping technique. Numerical simulations are performed to show that both tracking maneuver and vibration suppression can be accomplished effectively.

首先，采用自适应后步法结合主动振动控制技术设计了姿态跟踪鲁棒控制器，基于Lyapunov方法分析了系统的渐近稳定性；在此基础上，显性地考虑了执行机构动态特性问题，将整个设计过程分为两个步骤：第一步采用滑模控制技术设计了变结构虚拟控制器，给出自适应控制律的设计方法；第二步，将后步法与滑模控制技术相结合，设计了姿态跟踪鲁棒控制器，给出飞轮电压的输入算法及稳定性分析；最后，将提出的控制方法应用于挠性航天器的姿态跟踪控制，通过数值仿真对所提方法的可行性与有效性进行分析和验证。

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。