结构稳定性

In many practice problems such as to know the resonnance frequency of a structure and to know the critical value for the stability of a dynamical system,often need to compute the eigenvalues of a symmetric matrix. The chief method to compute the eigenvalues of a symmetric matrix is first to transformate the matrix to a symmetric tridiagonal matrix similarly and orthogonally, then to use the QR method with shift to the symmetric tridiagonal matrix.

很多实际问题，如求结构振动的固有频率，动力系统稳定性的临界值等常常归结为计算对称矩阵的特征值，而首选的计算方法是先把该矩阵正交相似变换成一个对称三对角矩阵，再对这个对称三对角矩阵用带位移的QR方法。1968年J.H。

As the research of turbidimeter begins too late in our country, comparing with the import turbidimeters, the domestic products is under-developed in performance and stability, but the import turbidimeter is complex to operate and much more expensive, so it can not used popularly.

由于起步较晚，国产浊度仪无论在性能上、稳定性上都与进口浊度仪有着明显的差距，但是进口浊度仪结构复杂、价格昂贵，不适合推广。

Some results of the criteria can also be applied to the motion stability analysis and design of uncontrolled rockets.

在这种情况下利用稳定性判据是非常实用的'而且这种判据还可以为弹体结构参数和发动机参数的确定提供依据。

In general, large-span cable-stayed and suspension bridges require bridge towers with a length of more than tens or hundreds of meters. Due to the unproportionate slenderness ratio, the bridge tower becomes vulnerable to air and thus easy to be distorted or to vibrate, which will affect the stability of the entire bridge structure. Therefore, it is of great significance to carry out an in-depth research on the force feature of the bridge tower in a flow field.

大跨度的斜拉与悬索桥，往往都需要建造数十米甚至上百米的桥塔，过大的长细比，使得桥塔在流场中受到气体的作用容易发生变形或振动，从而影响了整个桥梁结构的稳定性，因此，深入细致地研究桥塔在流场中的受力特性非常有必要。

The untranslated regions of many mRNAs contain sequence and structural motifs that are used to regulate the stability, localization, and translatability of the mRNA.

很多mRNAs的非翻译区包含用于调控mRNA的稳定性、定位和可译性的序列和结构motifs。

On the basis of molecular design, urushiol and tyrosine, with unique chemical structure, were selected as units to fabricate five kinds of stable and functional multilayer films via layer-by-layer self-assembly method.

本论文在对自组装膜的发展历史、自组装技术进行综述的基础上，从分子设计的思想出发，选用具有独特结构和性能的功能分子——漆酚和酪氨酸作为组装基元，以层层自组装技术制备了五种新型的，具有高稳定性的功能多层膜。

The linear method being used to calculate the critical wind speed of aerostatic stability by national guideline is expatiated.

提出了基于ANSYS的计算大跨径桥梁静风稳定性的非线性有限元法，充分考虑了结构的几何非线性及静风荷载的非线性。

Based on the method mentioned above, a nonlinear aerostatic stability analysis programme is developed.

最后 ，以一座主跨 10 0 0米的斜拉桥为例，分析了结构几何非线性、材料非线性和静风荷载非线性对大跨径桥梁空气静力稳定性的影响。

In the dissertation, one of the major mechanical problems——aerostatic stability problem of super-long-span cable-supported bridges is to be studied.

本文针对超大跨桥梁结构的关键力学难题之一——空气静力稳定性问题展开了研究。

In this paper,a method for computation of aerostatic stability of long span bridge s,the nonlinear finite element method,is put forward.

提出一种计算大跨径桥梁静风稳定性的方法——非线性有限元法，这种方法基于ANSYS，充分考虑了结构几何非线性及静风荷载非线性的影响。

This one mode pays close attention to network credence foundation of the businessman very much.

这一模式非常关注商人的网络信用基础。

Cell morphology of bacterial ghost of Pasteurella multocida was observed by scanning electron microscopy and inactivation ratio was estimated by CFU analysi.

扫描电镜观察多杀性巴氏杆菌细菌幽灵和菌落形成单位评价遗传灭活率。