查询词典 simultaneous equations

At the same time, the characteristic equations of the controlled systems with time delays are transcendental equations and belong to infinite dimensional systems, so it is difficult to study the time delay systems in mathematics theory and also difficult to obtain good performance for the time delay systems using the controller designed by classical control theory.

同时，由于含有时滞的控制系统的特征方程是超越方程，属于无穷维系统，对时滞系统的研究在数学理论上是非常困难的，有很高的理论价值，而且通过经典控制理论设计出来的控制器对时滞系统很难得到良好的控制效果。

There exists a dual symmetry between the equations of motion and the Maurer-Cartan equations of the type IIB superstring on AdS〓 S〓. We generalize the finite dual transformation to the infinitesimal dual transformation by the twisted dual.

根据Euler-Lagrange运动方程与Maurer-Cartan方程的扭曲对偶变换，我们可得到AdS〓×S〓中IIB超弦的Lax平联络及其相应的可积的相容条件，由此可以说明体系是一个可积系统。

2Nd order - Transport Equations: Integrability Conditions Yield Transport Equations, Complete Specification of Zero Order f

二阶- 传输方程式：可积分条件决定传输方程式，零阶f的完整描述

In the second chapter, modefied Taylor\'s expansion method is studied for solving Fredholm-Volterra integral equations, several illustative examples are given to show the efficiency of the proposed method. More over, by simple algebra, the modified Taylor\'s expansion can also be used to solve integral equations with weakly singular kernel, and the corresponding accuracy is dramatically promoted.

第二章重点讨论了应用Taylor展开方法解Fredholm-Volterra积分方程，通过数值例子，表明了该方法的简单有效性，特别应用于具有弱奇异核积分方程获得了更高精度的解。

New boundary integral equations for the torsion problem of an isotropic bar with curvilinear cracks are derived by using integration by parts and other techniques to the traditional boundary integral formulations. And the boundary integral equations for the torsion problem of an anisotropic bar with curvilinear cracks are also derived by using the isotropicalized boundary element method. Then the anisotropic problem can be solved on the base of the boundary element method of isotropic problem.

然后用各向同性化方法，将各向异性材料裂纹柱体的扭转问题转化为各向同性材料的问题，在各向同性材料裂纹柱体扭转问题的新的边界积分方程的基础上，推导出了适用于各向异性材料裂纹柱体扭转问题的边界积分方程，然后按已推导出的各向同性问题的边界元法求解。

Thin film equations; nonlinear cross-diffusion systems; two-dimensional nonlinear reaction-diffusion equations; invariant subspace method; invariant sets

基础科学，数学，数学分析薄膜方程；非线性交错扩散方程组；二维非线性反应扩散方程；不变子空间方法；不变集

The constitutive equation between current density vector and electric field strength vector is tranformed into s-domain by the principle of Laplace transform,and the inverse Laplace transform is adopted for the explicit equations between them in time-domain. Finally through exponential time stepping,the FDTD iteration equations are obtained,which can be easily solved in discrete-time-domain.

该方法是将电流密度矢量与电场强度矢量之间的本构方程基于拉普拉斯变换原理转到复频域，然后再逆变换到时域得到它们之间显式的方程，最后再结合指数差分，得到离散时域的显式的FDTD迭代方程，解决了本构方程中电流密度矢量的分量相互耦合而不易直接离散的困难。

It is able to perform spatial transformational movement, rotation, hoisting, tilting, planar rotation and tilted rotation. Based on configuration analysis, kinematic position equations were formulated, kinematic model of parallel fine-tuning structure was discussed as a key and inverse position analysis and velocity mapping equations were presented. Kinematic simulation of the mechanism was conducted using MATLAB software. A case study was provided, which applied the mechanism in tunnel erector assembling manipulators.

通过对该机构进行分析研究，建立其运动学位姿方程，重点探讨了并联微调机构的运动学模型，建立了其位置逆解与速度映射解析方程，运用MATLAB软件对该机构进行了运动学仿真分析；同时提供了该串并联机构应用于隧道管片拼装机械手的具体实例。

Inverse M-matrices often occur in relation to systems of linear or non-linear equations or eigenvalues problems in a wide variety of areas including finite difference methods for partial differential equations, input-output production and growth model in economics, iterative methods in numerical analysis, and Markov processes in probability and statistics.

其中包括偏微分方程的有限差分法、经济中的投入产出和增长模型、数值分析中的迭代法以及概率论和数理统计中的马尔可夫过程。

Summary: The concept of matrix and its determinant computing, matrix determinant, matrix sub-block with the elementary transformation, invertible matrix, rank of matrix; vector and its computation, the linear relationship between vector, vector group of rank; linear equations of the nature and structure of linear equations; matrix eigenvalue and eigenvector, similar to matrix and matrix diagonalization conditions, the standard quadratic form with the normal forms, quadratic and symmetric matrix There are qualitative.

内容提要：行列式矩阵的概念及其运算，方阵的行列式，矩阵的分块与初等变换，可逆矩阵，矩阵的秩；向量及其运算，向量间的线性关系，向量组的秩；线性方程组的性质与结构，线性方程组的求解；矩阵的特征值与特征向量，相似矩阵与矩阵可对角化条件，二次型的标准形与规范形，二次型和对称阵的有定性。

It's bell can reach over a meter in diameter.

它的身体最大可以达到直径1米多。

Now they are overdue and I shall have to pay a fine.

现在他们过期了，我不得不付罚款。