查询词典 method of perturbation

A kind of stability method is presented for a class of uncertain nonlinear system with perturbation and time delay.

针对一类有参数摄动和时延的非线性不确定性系统，提出了一种稳定性分析方法。

Probability perturbation finite element method for response analysis of multi-degree-of-freedom nonlinear vibration systems with random parameters

非线性因素会对系统解耦产生影响，因此工程实际中的非线性隔振系统一般为多自由度系统，同时，船舶机械隔振系统的基座应视为具有一定机械阻抗的弹性体。

Based on the above results, the problems of the electromagnetic interaction between a perfect conducting plate and 1-D/2-D conducting slightly random rough surface and the problems of the electromagnetic interaction between a dielectric spherical particle and dielectric slightly random rough surface are investigated. By using the reciprocity theorem, Small Perturbation Method and Physical Optics approximation, the solution for the composite scattering field from the composite target is derived and evaluated, and the numerical results are discussed and analyzed.

在此基础上，用互易性原理分别研究了一维、二维导体微粗糙面与其上方金属导体平板目标的复合电磁散射及介质粗糙面与其上方球形粒子的复合电磁散射，结合互易性原理和粗糙面散射微扰法及物理光学近似导出了复合散射场的计算公式并进行了数值计算，对计算结果进行了讨论和分析。

First, the modal perturbation method based on Ritz vectors is applied to solve the dynamic characteristics of Timoshenko deep beam including the effects of shear deformation and rotational inertia.

首先建立了钢筋混凝土深梁的求解方程，然后提出了求解Timoshenko梁特征值问题的模态摄动法，最后通过算例，说明不同含钢率下钢筋混凝土深梁的自振特性的变化情况。

First,an orthogonal method is used to get the perturbation into a series of functions.

正则摄动法和加权残值法是求解非线性力学问题的两个常用方法。

A general matrix perturbation method for complex modes using singular value decomposition;2. The modal character,the error of the substituting by real modes and the best way to extract real modes from complex modes are discussed.

建立运动方程，用第一振型将主体结构展开，针对非经典阻尼和非对称结构以及脉动风谱为非有理分式风谱的情况，运用复模态理论将所得方程进行解耦，获得了以第一振型表示的结构随机风振响应的解析解。

Using the perturbation method and Stroh's formula, a nonideal crack, which is mathematically sharp and the opposing crack faces still have a gap in which a stiffless dielectric fills, the two-field problem is reduced to a standard Riemann-Hilbert problem. The internal electric field distribution is obtained by solving a singular integral equation, and then the full field both inside and outside the crack is obtained and the electro-mechanical intensity factors to the first order of accuracy are given.

采用摄动方法对裂尖理想尖锐而裂纹面又具有一定张开的非理想裂纹进行分析，裂隙内含有无刚度的各向同性电介质，利用Stroh公式，将二域问题化为标准的Riemann-Hilbert问题，裂隙内电场分布通过解一个奇异积分方程获得，从而得到裂纹内外的力电全场分布，进而给出一阶精度下的力电强度因子的表达式。

The following are the major work in this thesis which has been studied and still needs to be studied further in the future: 1 An improved adjoint variational method is developed, thus it can be applied to the LAGFD-WAM Wave Numerical Model for data assimilation; 2 A linear evolution equation of spectral perturbation is derived in order to analyze its increasing or decreasing mechanism.

本论文主要完成了以下几个方面的研究： 1）建立了推广形式的共轭变分同化方法，使之能够应用于LAGFD-WAM海浪数值模式； 2）导出了扰动谱线性演化方程，分析了扰动谱增长、衰减机制，考察了涌浪情况下扰动谱的持续时效问题及风浪情况下扰动的演变过程； 3）利用波谱共轭方程初步分析了同化模型中距离泛函的敏感性及敏感区域空间分布； 4）将推广的共轭变分方法应用于海浪谱能量平衡方程，建立了连续形式的海浪同化模型，特别是严格导出了风输入、破碎、底摩擦、波波非线性相互作用和波流相互作用各源函数的共轭源函数表示式； 5）分别进行了波谱层次上和有效波高层次上的同化试验，并对数值结果进行了分析。

At last, about how to improve teaching stationary state perturbation method is briefly reviewed on base of modern teaching theory and self-study experience.

最后结合现代教育理论及本人的学习体会就如何搞好定态微扰论的教学进行了简单阐述。

A general unstable chaotic solution of the Duffing oscillator in a double-well with weak periodic perturbations is obtained by using the direct perturbation method in this paper.

利用直接微扰的方法求出了双阱中具有弱周期微扰的Duffing 振子混沌解的一般表达式。

In the United States, chronic alcoholism and hepatitis C are the most common ones.

在美国，慢性酒精中毒，肝炎是最常见的。

If you have any questions, you can contact me anytime.

如果有任何问题，你可以随时联系我。