查询词典 time of vibration

The bifurcation and chaos behavior of impact and rubbing fault rotor system caused by the parameters of nonlinear rigidity, rotor rotating speed, eccentric mass is analyzed, in the numerical value analysis method. The bifurcation diagrams, maximum Lyapunov exponent diagrams, Poincaré maps, phase plane portraits, trajectories of journal center, time-history curve, amplitude spectra diagrams of the rotor motion are used. The convert and evolution course of periodical response, quasi-periodical response, double-periodical bifurcation, chaos of the system response is analyzed.(3). It is deduced that the general differential equation of bending-torsional-pendular coupling vibration about rotor with the gyroscopic moment. On the basis of this equation, the general differential equations of coupled bending, torsional and pendular nonlinear vibration about rotor with unbalance character and rubbing character are deduced.

2建立了具有非线性刚度的转子系统在非稳态非线性油膜力作用下的径向碰摩动力学微分方程，并应用含高阶余项的非线性动力方程的线性化数值法研究了此类系统响应的复杂动力学行为，利用转子响应的分岔图、最大Lyapunov指数曲线、Poincaré截面映射、时域波形、相轨线、轴心轨迹、幅值谱等图形分析了系统响应的周期运动、拟周期运动、倍周期分岔、混沌等运动形式的转化与演变过程，重点研究了非线性刚度、转子转速、偏心质量等系统参数对碰摩故障转子系统的分岔和混沌行为的影响。

The main reason of wind vibration is a pulsant part of nature wind, unremitting vibration may bring large distortion and stress in the structure, and at the same time, it will bring fatigue damnification to the structure.

自然风中的脉动风分量是引起结构风激振动的主要因素，持续的振动可引起建筑幕墙结构产生较大的变形及应力，同时引起结构的疲劳损伤。

AR model in linear filter theory is adopted to simulate pulsant wind. Combined with some typical cable-membrane structures, research on self-vibration of the structure has been conducted. Based on the previous work, the influence caused by the vertical wind component on the membrane roofs has been analyzed in time domain. It includes the vibration laws of the structure under separate horizontal wind component, separate vertical wind component and the collective horizontal wind component and vertical wind component. Significant conclusions have been drawn from the analysis.

然后本文采用线性滤波器法中的AR模型对风速场进行了模拟；之后又结合典型的张拉索膜结构研究了膜结构的自振特性；在此基础上，本文研究了索膜结构在竖向脉动风影响下的风振响应特性，其中分别研究了张拉索膜结构在单独水平风，单独竖向风以及水平风和竖向风共同作用下的振动规律，得出了有关重要结论。

A uniform mixture of silicon powder (granularity≤0.044 mm) and polyvinyl alcohol solution (PVA,5 wt%) in response to a certain proportion was prepared.After sieving,prilling and vibration,the mixture was packed.Effects of the vibration frequency (14～50 Hz) and time (10~230 s) on packed density of powder were studied.

摘 要：将Si粉（粒度≤0.044 mm）和聚乙烯醇水溶液(聚乙烯醇质量分数为5%)按一定比例混匀，过筛造粒后，振动装料，研究了振动频率（14～50 Hz）和振动时间(10~230 s)对粉料填充密度的影响。

It is considered that fatigue crack is early produced on drill pipes, because the vibration load of drilling tools in air drilling is more severe than that in mud drilling. Fatigue cracks easily occur under alternating vibration. Because the current wellhead detecting instruments can not be used to reflect the change of pump pressure produced after drill pipe piercement timely and accurately, effective measures can not be taken in time to prevent the expansion of fatigue cracks. As a result, drill pipe fracture accidents occur.

失效分析表明，钻杆属于早期疲劳断裂，断裂主要原因是在空气钻井过程中钻具受到的震动载荷远大于钻井液钻井过程中的震动载荷，在交变的震动载荷作用下，钻具容易产生疲劳裂纹；由于现有的井口检测仪表不能精确及时反映钻杆刺穿之后产生的泵压变化，无法及时采取预防措施，疲劳裂纹不断扩展，最终导致了钻杆断裂失效。

It is considered that fatigue crack is early produced on drill pipes, because the vibration load of drilling tools in air drilling is more severe than in mud drilling. Fatigue cracks easily occur under alternating vibration. Because the current wellhead detecting instruments can not be used to reflect the change of pump pressure produced after drill pipe piercement timely and accurately, effective measures can not be taken in time to prevent the expansion of fatigue cracks. As a result, drill pipe fracture accidents occur.

失效分析表明，钻杆属于早期疲劳断裂，断裂主要原因是在空气钻井过程中钻具受到的震动载荷远大于钻井液钻井过程中的震动载荷，在交变的震动载荷作用下，钻具容易产生疲劳裂纹；由于现有的井口检测仪表不能精确及时反映钻杆刺穿之后产生的泵压变化，无法及时采取预防措施，疲劳裂纹不断扩展，最终导致了钻杆断裂失效。

But because of its big slenderness ratio, smaller rigidity and damping, it is easy to cause a larger vibration in the windload and iceload function and so on, mast structure destruction accidents frequently occurred, has caused engineering and academic circles\\\s concern, this article summarizes the main structure damage diagnosis methods, carrys on preliminary dynamic analysis and the time-frequency distribution analysis with the vibration signal to the mast structure, and proposes the signal processing method is a appropriate method on the diagnosis to the mast damage.

但是，由于桅杆结构长细比很大，刚度、阻尼较小，在风荷载、裹冰荷载等作用下容易产生较大幅度的振动，桅杆结构的破坏事故时有发生，引起了工程界和学术界的重视，本文总结了几种主要的结构损伤诊断方法，并对桅杆结构进行了动力分析和振动信号时频分析，并提出信号处理的时频方法对桅杆损伤进行诊断比较合适的。

The thought of suppressing the vibration of structure with multi-part composite structure is put forward for the first time, the motion and control equation is derived, and the effect of vibration-reduction and its influential parameters are studied.

提出了利用多单体组合来抑制结构振动响应的思路，推导了其运动和控制方程，并对其减振效果和影响参数进行了研究。

It is stated, on basis of analysis on the blasting theories at home and abroad, that parameters, such as vibration velocity and vibration time should be introduced to analyze the influence of blasting on the surrounding structures. In the paper, the influence imposed by the blasting excavation of tunnels with extralarge crosssections is simulated, with Guanziling tunnel on LanzhouChongqing railway as an example.

在分析国内外爆破振动理论的基础上阐述要根据具体的工况，有针对性地引入振动速度、振动时间等多种参数进行分析，且以兰渝线关子岭特大断面隧道爆破为依托，应用数值分析方法，模拟特大断面隧道爆破振动对周边建筑物的影响。

The main research contents are as follows:1. Through massive calculation, analysis and comparison, sum up the similarities and differences between the special-shaped cross sections and rectangular cross sections in mechanical features, between reinforced concrete special-shaped columns and rectangular columns in load-bearing capacity, ductility performance and provide necessary basic concepts and data for further understanding the characteristics of the special-shaped columns;2. Through massive elastic calculations and elasto-plastic analysis, under the preconditions of satisfying the code's requirements for axial compression ratio, limit value of lateral displacement and load-bearing capacity of normal section,oblique section and beam-column joint, under circumstances of different intensity of earthquake, structure dead weight, sort of site and column grid bay dimension, the variation regularity of maximum suitable height of structure, and thus sum up the maximum suitable height of structure for code for the purpose of macro-control while deciding the design scheme;3. Make a preliminary study on the stress feature of reinforced concrete special-shaped column and Z-shaped column of which the ratio of limb length to limb thickness is between 4~5 ,and the preliminary design method is suggested;4. Through elato-plastic time history dynamic analysis of typical projects, check up the weak storey of the special-shaped column structure and yielding, breaking and collapse mechanism to satisfy the earthquake resistant requirement to buildings of remaining stand under strong earthquake;5. Derive for project use simplified calculation formula of vibration period, suitable vibration period, suitable rigidity of special-shaped column structure through theoretical analysis, and provide an easy and practical method for deciding the structure scheme economically, safely and reasonably;6. Based on the study achievements in theory and massive analysis and calculations of this paper, sum up the regularities of inner force, deformation of special-shaped column structure and seismic conceptual design, and thus the suggection of seismic design of special-shaped column structures is presented.

本文研究的主要内容如下：通过大量的计算、分析和对比，总结出异形截面与矩形截面在力学特性、钢筋混凝土异形截面柱与矩形截面柱在承载能力、延性性能等方面的异同，为深入了解异形截面柱的特点提供必要的基本概念和数据；通过大量的弹性及弹塑性计算分析，在满足规程对轴压比、侧移限值及正截面、斜截面、节点承载力抗震验算要求的前提下，在不同抗震设防烈度、结构自重、场地类别及柱网开间尺寸情况下最大适宜高度的变化规律，并在此基础上总结归纳出异形柱结构的最大适用高度规定，可用于规程，以便于在确定方案时起到宏观控制的作用；对肢长与肢厚比在4～5的钢筋混凝土异形截面柱及Z形柱的受力特点进行初步探讨，提出初步的设计方法；通过对典型工程的弹塑性动力时程分析，检验异形柱结构的薄弱层及屈服、破坏、倒塌机制，以达到建筑物大震不倒的抗震设防要求；通过理论分析，推导出异形柱结构自振周期，以及适宜自振周期、适宜刚度的工程实用简化计算公式，为经济、安全、合理地确定结构方案提供简便实用的方法；在本文理论分析、计算以及大量的研究成果基础上，总结归纳出异形柱结构内力、变形的规律及抗震概念设计内容，并在此基础上提出异形柱结构的抗震设计建议。

Metrorrhagia is also gynaecological problems of common diseases.

崩漏是妇科常见病也是疑难症。

WordFTP gives you the convenience and timesaving you need.

wordftp让您的方便和省时您所需要的。