非线性振动

By virtue of method of continuum approximate limit, we obtained the solitons of the vibration of lattice in one-dimensional harmonic and inharmonic chains of polarized molecule, under the conditions considering and inconsidering the interaction of exciton with phonon, through solving moving equations of exciton and phonon.

运用连续极限近似方法，通过求解声子和激子的运动方程，得到了在不考虑激子与声子的相互作用和考虑激子与声子相互作用两种情况下的极性分子简谐链和非简谐链中晶格振动的孤子解，并得出了激子与声子的相互作用的非线性效应类似于晶格三次势的非线性效应，以及相同的非线性效应不论是同时作用还是单独作用都具有相同的非线性效应的结论。

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。

A time-frequency analysis method based on HOS is proposed to study the girder gust response, and the supreme mode contributed to gust response and the modal coupling could be identified using this method.

二、提出利用基于高阶谱的时频分析研究大桥非平稳、非线性风致振动响应，能够得出对不同测点风致振动响应贡献最大的模态和耦合振动模态。

Firstly, this paper researched the mechanism of tubing string vibration when natural gas flows in horizontal well tubing string. Secondly, established whole tubing string undamped and damped vibration system model according as reasonable assumption data of one horizontal well. Apply finite element analysis software to calculate tubing string natural characters, simple harmonic dynamic behavior of stable gas production and nonlinear dynamic behavior. Finally, this paper carried out the safety varied frequency of gas well and the method of vibration reduction.

本文首先从理论和数值模拟研究了天然气在水平井油管柱内的流动诱发油管柱振动的机理，然后在合理假设的基础上结合某水平井数据建立了全井段油管柱无阻尼和有阻尼振动系统模型，利用有限元软件计算分析了油管柱固有特性、稳产简谐动力学响应和非线性动力学响应，针对油管柱振动规律提出了天然气安全调节频率范围和减振措施。

Finally, a nonlinear dynamic model of vibration friction system with compaction equipment was proposed. Its resonance and non-resonance responses were obtained.

建立了基于振动压路机的振动摩擦系统非线性动力学模型，利用渐进法得到了振动压实过程的共振响应和非共振响应。

Some sufficient criteria were obtained for oscillation of all solutions of such systems under first boundary value conditions by employing Gauss＇ divergence theorem, the integral inequalities and some results of the functional differential equations.

研究一类具非线性扩散系数的中立型双曲泛函偏微分方程组的振动性，利用Gauss散度定理、积分不等式和泛函微分方程的某些结果，获得了该类方程组在第一类边值条件下所有解振动的若干充分判据，结论充分表明振动是由时滞量引起的，同时也揭示该类方程组与普通双曲型偏微分方程组质的差异。

On the basis of phase space analysis about measured vibration signals,the characteristics of special nonlinear autonomous vibration about the structure included in the system were obtained.

在实测的振动信号相空间分析的基础上，得到系统所包含的结构振动的特殊非线性自主振动的特征。

In the analysis, a nonlinear wave vibration equation of the thin cylindrical shell including damping and items due to geometric nonlinearities was established and then transformed by Galerkin's method. With different combinations of modes different nonlinear differential equations in modal coordinates were obtained. The Runge Kutta method was used to solve the equations numerically and some features of nonlinear wave vibration were discussed.

在研究过程中，首先，考虑阻尼并引入几何非线性项，建立薄壁圆柱壳的非线性波动方程，然后，采用Galerkin方法对波动方程进行转换，选取不同的模态组合，得到相应模态坐标下的非线性微分方程，最后用Runge-Kutta法进行数值计算并对圆柱壳的非线性波动振动特性进行了分析。

Mathematical model of nonlinear vortex-induced vibration was presented for predicting the nonlinear dynamic responses of submerged floating tunnel tethers which were subjected to wave, current and oscillatory displacements at their upper end in horizontal and vertical directions.

建立了水中悬浮隧道锚索在波流场中涡激振动的非线性数学模型，考虑了锚索的几何非线性对其涡激振动的影响，并应用有限差分法求解了锚索的运动控制方程。

First, the angular velocity function and maneuver load for certain maneuver flight (including hover, dive-hike and these two combined) are set up. The simulation results of the vibration of double-disk rotor system with cantilever supported on rigid bearings show that rotor would be apparently deformed under maneuver load. Second, the performance of oil force of SFD in maneuver flight is analyzed. The results show that in maneuver flight, the SFD with centering spring will become eccentric and its oil force will be time-related and offset-related. Then, SFDs are introduced into typical Jeffcott rotor system. The whole system will be statically displaced in maneuver flight and the nonsynchronous components of oil force appear in the response of rotor system.

首先，建立了水平盘旋、俯冲拉起及盘旋+俯冲拉起复合机动三种机动飞行条件下的机动角速度函数，并确定了对应机动飞行条件下的机动附加载荷(附加离心力和附加陀螺力矩)，分析了带刚支的双盘悬臂转子系统在机动飞行条件下的振动特性，发现发动机转子在机动飞行时会发生明显变形；随后，分析了非定心挤压油膜阻尼器的油膜力特性，机动飞行时，油膜轴颈在机动附加载荷的作用下偏离外环中心，使得带定心弹支的挤压油膜阻尼器也变成了非定心挤压油膜阻尼器，其非定心挤压油膜力是瞬态时变的，并且与SFD油膜轴颈偏移量和进动形态有关；然后，在经典的Jeffcott转子系统中引入带定心弹支的挤压油膜阻尼器，分析了机动飞行时非线性转子系统的振动特性，发现挤压油膜阻尼器油膜力的非协调特性也反映到转子系统的振动响应中；之后，对机动飞行条件下带挤压油膜阻尼器的双盘悬臂转子系统的振动特性进行了分析，并重点分析、总结了俯冲拉起机动飞行时，系统结构参数和工作状态参数(转速比、机动飞行半径、机动角速度等)对该系统振动特性的影响。

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。