查询词典 method of perturbation

In this paper,We use the singular perturbation theory and method to study the two types of singular perturbation problems with fractional derivative.

本文应用奇异摄动理论和方法研究了含有分数阶导数的两类奇异摄动问题。

In this paper, a high order accuracy difference method is presented for solving unsteady convection diffusion equation by using Implicit Perturbation Finite Difference scheme. Firstly, we use the steady convection diffusion equation, the constant coefficients of this equation are expanded to power series of grid-spacings, then the high-order Perturbation Finite Difference scheme is obtained by determining the coefficients of the power series. Put this scheme on unsteady convection diffusion equations and modified it, the IPFD scheme is constructed.

本文利用摄动差分思想，对定常对流扩散方程中的空间微商系数进行摄动展开，展开幂级数系数通过消去摄动格式修正微分方程的截断误差项求出，由此获得方程的隐式摄动差分格式，将此方法应用于非定常对流扩散方程，并加以修正，得到该方程的修正隐式摄动差分格式。

Moreover, the choices of the singular perturbation parameter are studied, and a new simple and convenient method to estimate the bound of the singular perturbation parameter is designed.

此外，本文还研究了奇异摄动小参数的选取，提出了一种新的简单易行判定稳定性界的方法。

In order to solve this model, perturbation method is employed and the solution is expanded into a series in powers of perturbation parameter.

利用小扰动方法处理了任意形状非均质油藏不稳定渗流问题，将解表达成关于扰动参数的无穷幂级数形式。

The conditional nonlinear optimal perturbation is a new theoretical method proposed by Mu,et al in 2003, which is an extension of the linear singular vector to nonlinear regimes. It has become a powerful tool to study some issues of nonlinear systems like predictability, sensitivity and so on, because it overcomes the defect of LSV for not representing the fastest developing perturbation of a nonlinear system.

条件非线性最优扰动是Mu等2003年提出的一个新的理论方法，它是线性奇异向量在非线性情形的推广，克服了线性奇异向量不能代表非线性系统最快发展扰动的缺陷，成为非线性系统可预报性和敏感性等研究新的有效工具。

The conditional nonlinear optimal perturbation is a new theoretical method proposed by Mu , et al in 2003, which is an extension of the linear singular vector to nonlinear regimes. It has become a powerful tool to study some issues of nonlinear systems like predictability, sensitivity and so on, because it overcomes the defect of LSV for not representing the fastest developing perturbation of a nonlinear system.

摘要条件非线性最优扰动是 Mu 等2003年提出的一个新的理论方法，它是线性奇异向量在非线性情形的推广，克服了线性奇异向量不能代表非线性系统最快发展扰动的缺陷，成为非线性系统可预报性和敏感性等研究新的有效工具。

Then,we presented an analytical method to solve the dynamic stresses and perturbation of magnetic field vector under thermomagnetic shock,and obtained the response histories and distributions of the dynamic stresses and the response histories of perturbation of magnetic...

提出一种解析方法求解在热磁冲击作用下厚壁圆筒的动应力和磁场矢量扰动，得到柱体内动应力响应历程和分布规律及磁场矢量扰动的响应历程和分布规律。实例计算表明该方法是简单、有效的，并给出了一些有实际意义的结果。

First, the Lyapunov functional and variation of constants method are adopted to study the effect that Sigmoid function and the relation of resistance, capacitance and current in Hopfield neural networks have on the stability of networks. The stability criterion constructed by physics parameters is obtained. Thus how the constrained relation of physics parameters affects the stability of Hopfielf neural networks is clear. Based on the study above, the perturbation model of recurrent neural networks is constructed. And the theorems of the existence of solution of perturbation model are presented.

首先，采用Lyapunov泛函法和常数变易法研究Hopfield神经网络中给出的电阻、电容、电流之间的关系以及Sigmoid函数对网络稳定性的影响规律，得出仅由物理模型参数构成的稳定性判据，从而弄清物理模型参数约束关系对Hopfield神经网络稳定性所起的作用，在此基础上，构建了递归神经网络的扰动模型，并通过讨论扰动模型解的存在性问题，给出递归神经网络扰动模型解的存在性定理。

To introduce perturbation corrections of lattice strain intosemiempirical MO calculations,we have written out the programs,STRAIN+SPHF,for calculating perturbation corrections of lattice strain,based onsemiempirical MO calculation program package MOPAC3.0.In principle,the theoretical method and program for calculating corrections of latticestrain can be employed for the studies of growth mechanisms for diamondfilms or other non-metallic films on any non-metallic heterogenic substrates.

运用引入晶格应变修正的AM1半经验分子轨道方法和不包含该修正的AM1方法，通过在Si(100)和(111)衬底表面上提取H原子以及CH3和C2H2吸附过程的计算比较研究，发现包含应变修正的结果比不包含该修正的结果更准确地描述了Si衬底上发生的化学反应过程，并且还能够揭示出无应变修正结果中没有揭示出的表面物理化学现象。

According to the structural properties of tuning blade-disk assemblies, the matrix perturbation method is used to analyze the influence of mistuning on the natural vibration characteristics. The formulas for perturbation values of first and second order are derived.

根据谐调叶盘的结构特点，用矩阵摄动法分析了失调对叶盘固有振动特性的影响，推导了孤立特征值和密集模态组二种情况下固有频率和振型的一阶、二阶摄动计算公式。

Liapunov—Schmidt method is one of the most important method in the bifurcation theory.

Liapunov—Schmidt方法是分叉理论的最重要方法之一。

Be courteous -- even when people are most discourteous to you .

要有礼貌──即使当別人对你最不礼貌的时候。