自然振动

The low-dimensional Galerkin method is generalized to solve the flow around arbi-trarily translating circular cylinder.Active control problems of wakes behind circularcylinders are numerically investigated by only small number of modes.The in-line andtransverse oscillation of a circular cylinder with proper frequency produce Karman vor-tex street successfully in some subcritical regime,vhereas the transverse oscillation of acircular cylinder with 1.8 times the natural shedding frequency can effectively suppressthe Karman vortex street at a slightly supercritical Re.

将低维Galerkin方法推广至可以求解任意平移运动圆柱的绕流问题，用较少的模数值研究了圆柱尾迹的主动控制问题，在亚临界Re数下圆柱以适当的频率沿流向和横向振动均成功地激发出Karman涡街；而在略高于临界Re数下圆柱以1.8倍自然脱涡频率沿横向振动明显地抑制了Karman涡街；再现了超临界Re数横向及流向振动圆柱绕流的频率锁定等复杂非线性现象。

Vibration Hull 船体振动 The Builder to determine natural frequencies of vertical and horizontal vibrations for hull girder and deckhouse to ensure that excitation frequencies of main engine and excitation frequencies of propeller are not similar.

建造方应确定船体纵珩和甲板室的垂直和水平方向振动的自然频率，从而使主机的激励频率与螺旋桨的激励频率不同，对船尾潜在的板振动应加以分析并通过相应的设计加以消除。

The natural frequencies, the equation of motion and the node of vibration are discussed for the vibration system of a cradle dynamic balancing machine. Some general remarks concerning the design are make. An analysis by the method of four measuring plane are given together with the actual electric circuits. Furthermore, the general ideas about the KQD-1 type cra-dle dynamic balancing machine are introduced as an example.

本文讨论了框架式动平衡机振动系统的自然频率运动方程、振动中心等问题；指出设计时应注意的事项，对四测量平面法作了理论分析，并给出其实际电路：以KQD—1型框架式动平衡机为实例作简要的介绍。

The instruments give a natural vibrational energy to a music that is never obtrusive.

这些文书提供一个自然振动能量，一个音乐是永远不会碍眼。

Proceeding from the kinetic equation, the occurrence of muscular fibre spontaneous oscillation is explained in a natural way, the period of isotonic spontaneous oscillation and the oscillation curves are consistent with experimental data, and some new theoretical results are presented.

从动力学方程出发，肌纤维自发振动的发生条件得到了自然解释，所给出的振动周期和振动曲线同实验结果相符，并给出了一些新的理论结果。

You said, trustingly and knowingly, from your Nonphysical Perspective, I'll go forth into this perfect Earth time/space reality because I know that it is the perfect environment to produce, within me, natural asking, and I know that when I, in a vibrational way, ask, that God, if you want to call it that, or Nonphysical Energy or Creative Life Force or All-That-Is, answers the vibrational request.

你在来到这个物质世界以前，从你的非物质视角，曾经坚信不疑而且胸有成竹地说过，"我将前往这完美的地球时空现实中，因为我知道，这是能使我自然产生'要求'的完美环境，而且我知道，当我以振动的方式要求时，那个人们常常称之为无所不能的上帝的，那个非物质能量，那个创造生命的力量，那个涵盖一切的真理，就会响应我的振动方式的要求。"

Furthermore, as the oscillating frequency of the cylinder approach the natural vortex shedding frequency, because of the phenomenon of resonance in the channel flow, and the heat transfer rate is enhanced more remarkably.

此外，当圆柱振动的频率接近流场的自然振动频率时，会与管道内的流体产生共振的现象，此现象能够大幅的增加流体的扰动，并且扰乱管道内的流场以及温度场，产生较佳的热传增益。

Firstly, the mechanism of heat transfer enhancement by oscillation heat surface is discussed in natural convection scene. For different oscillation amplitude and Rayleigh number, the frequency that the heat transfer rate of oscillation heat surface is higher than non-oscillation condition is found and called critical oscillation frequency. The limitation enhancement of similar physical model is still researched by this study in mixed and forced convection scenes for different amplitude and Grashof number. Generally, that a heat surface subject to a oscillation motion is advantageous to convective heat transfer is a well-known tuition.

首先探讨在垂直管道内振动高温面於自然对流领域内提升高温面热传效率的机制，并且针对不同的振幅与雷利数求得加入振动条件后，高温面散热效果可以优於稳态非振动高温面散热效果的临界振动频率；进而探讨当垂直管道流进入混合对流与强制对流范围时，在不同的振幅与葛瑞秀夫数下，亦可发现加入振动条件后，振动高温面之散热效果可以优於稳态非振动高温面散热效果的临界振动频率。

Firstly, the mechanism of heat transfer enhancement by oscillation heat surface is discussed in natural convection scene. For different oscillation amplitude and Rayleigh number, the frequency that the heat transfer rate of oscillation heat surface is higher than non-oscillation condition is found and called critical oscillation frequency. The limitation enhancement of similar physical model is still researched by this study in mixed and forced convection scenes for different amplitude and Grashof number.

首先探讨在垂直管道内振动高温面於自然对流领域内提升高温面热传效率的机制，并且针对不同的振幅与雷利数求得加入振动条件后，高温面散热效果可以优於稳态非振动高温面散热效果的临界振动频率；进而探讨当垂直管道流进入混合对流与强制对流范围时，在不同的振幅与葛瑞秀夫数下，亦可发现加入振动条件后，振动高温面之散热效果可以优於稳态非振动高温面散热效果的临界振动频率。

Depending on the general solution of the vibration of system given in the front, considerate that the nature wind is always in a gust form, model the load of wind on the canopy and trunk of tree as a impulse load on the free end of the staff, and gets the responses of vibration under these conditions, then picture the curve of the vibration.

根据之前得到的系统振动通解，考虑自然风多呈阵风形式的影响，将作用在树冠和树干上的风载简化为作用在弹性杆自由端质量团处的脉动载荷，进而分析并得到此条件下杆的振动响应，绘出此情况下杆的振动响应曲线。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。