查询词典 submatrix

On the one hand, the linear interpolation in plane makes it easy to separate the three-dimensional null subspace corresponding to rigid body motions, hence what is left to do is just to compute the inverse of a symmetric definite submatrix numerically.

在物理坐标系中的线性插值函数便于将三个刚体模式分离出来，从而只需计算对称正定子阵的逆，避免了求广义逆的数值困难；在参考坐标系中的高阶插值函数则可保持原平面弹性单元的列式方式。

First, it is discussed about the relation between the dynamic stiffness submatrix of the supports system with variable stiffness and damping and the optimum output-feedback matrix when the rotor-supports system is governed by the optimum control laws.

本章进一步研究转子—轴承系统变刚度阻尼支承振动主动控制问题，提出了在最优振动主动控制规律的有效频率范围以外，对转子—轴承系统进行次优振动主动控制的策略思想。

In this note the author showed that if s is nonnegative integer and A∈B n,n+s, then |R|=2 n if and only if A contains a submatrix which is permutation equivalent to the unit matrix of order n.

作者证明：如果s是一个非负整数且A ∈Bn ，n+s，那么｜R ｜=2 n 当且仅当A含有置换等价于n阶单位矩阵的一个子阵

Our results improve the former results. For periodic Jacobi matrix, some new spectral properties of periodic Jacobi matrix are given by studying the relationship of the eigenvalues of periodic Jacobi matrix and its n—1 principal submatrix. Applying these spectral properties, we present a necessary and sufficient condition for the solvability of an inverse problem of periodic Jacobi matrices and discuss the number and the relationship of its solutions. Furthermore, we propose a new algorithm to construct its solution and compare it with the former algorithms. As this inverse problem of periodic Jacobi matrix usually has multiple solutions as many other eigenvalue inverse problems, we study the uniqueness of this problem. And a necessary and sufficient condition is given to ensure its uniqueness, under which an algorithm is presented and the stability analysis is also given. Finally, we put forward a new inverse problem for periodic Jacobi matrix which has not been solved.

对周期Jacobi矩阵特征值反问题，通过研究周期Jacobi矩阵与其n-1阶主子阵特征值的关系，给出了周期Jacobi矩阵的一些新的谱性质；利用这些谱性质，研究了一类周期Jacobi矩阵特征值反问题，用新的方法推导出了该类特征值反问题有解的充分必要条件，并讨论了解的个数以及解与解之间的关系；此外，提出了一种新的构造周期Jacobi矩阵反问题解的数值算法，并与前人的算法做了一定比较；由于周期Jacobi矩阵特征值反问题和其他很多特征值反问题一样往往存在多个解，本论文给出了周期Jacobi矩阵反问题解唯一的充要条件，并发现周期Jacobi矩阵特征值反问题的解唯一当且仅当构造的矩阵满足一定的条件；在解唯一的情况下，给出了构造唯一解的数值算法，并做了相应的稳定性分析；最后，提出了一类新的有待于解决的周期Jacobi矩阵特征值反问题。

Commencing from the character analysis of overall stiffness matrix of finite element method, the author brings forward it which is important to realize full nonzero memory of overall stiffness matrix, obtains correlative interlink of nodal point from analyzing affiliated element of nodal point, conforms every submatrix's position in overall stiffness matrix, realizes full nonzero memory of overall stiffness matrix.

论文根据面向对象程序设计的特点，建立了有限元模型的相关类，给出了基本的程序设计框架。

Solving such a system would encounter some intricacies if its leading principal submatrix, i.e. the stiffness matrix, is rank deficient. This is believed to be one of the main reasons that many programmers would unwillingly give up the Lagrange multiplier method but select the penalty function method.

当其中的主子阵亏秩时，求解会遇到许多困难，这些困难往往是导致许多程序员放弃Lagrange乘子法而选择罚函数法的根本原因。

On the ground that the covariance between the disturbing gravity field elements is not isotropic, the covariance matrix has a complicated structure (its submatrix being not repetitive Toeplitz matrix) and thus its degree cannot be degraded with transformation matrix method, so it cannot be put into practice. So far, the application of least squares collocation to the modeling and data processing of the horizontal disturbing gravity field observations has not been found in literature.

由于水平扰动场元之间的协方差并非各向同性，导致协方差矩阵结构复杂(子矩阵不是 Toeplitz 循环阵)，不能利用变换矩阵将其降阶，无法付诸实践，迄今尚无最小二乘配置理论应用于水平扰动场元观测量的模型化公式和数据处理方法。

By perceiving the facts that average damages do not change the loading paths of a structure and that local damages will not increase component stiffness, the author presents the damage identification algorithms termed as Iterative Matrix Optimal updating and Constrained Submatrix Factor Adjustment .

根据一般损伤不引起荷载路径改变、局部损伤不会导致单元刚度增加等损伤问题的特点，提出损伤识别的"矩阵迭代优化修正法"和"带约束的子矩阵系数修正法"；并将子矩阵系数修正法推广为联合运用动力与静力测量值的损伤识别算法。

The Jacobi matrix rank one update problems, given either their mix-type eigenpairs or their pricinpal submatrix and defective eigenpairs(the eigenvalues of the matrix and some elements of the corresponding eigenvectors) are also discussed.

n阶对称箭形矩阵与n阶Jacobi矩阵一样只有2n-1个非零元素，类似Jacobi矩阵逆特征值问题的提法，本文提出并讨论了六类对称箭形矩阵逆特征值问题，研究了这类矩阵的结构性质，得到了问题有解的充分必要条件及求解的数值算法和数值算例。

These three algorithms can avoid to recompute the nth order head submatrix of the Jacobi matrix. Moreover, the last two algorithms are more stable, their precision can match well with the algorithm of Boley and Golub.

这三种算法都可以避免重构Jacobi矩阵的n阶首主子阵，并且后两种算法更稳定，数值精度可以(来源：A1cBC论c4文网www.abclunwen.com)与Boley和Golub的算法媲美。

It has been put forward that there exists single Ball point and double Ball points on the symmetrical connecting-rod curves of equilateral mechanisms.

从鲍尔点的形成原理出发，分析对称连杆曲线上鲍尔点的产生条件，提出等边机构的对称连杆曲线上有单鲍尔点和双鲍尔点。

The factory affiliated to the Group primarily manufactures multiple-purpose pincers, baking kits, knives, scissors, kitchenware, gardening tools and beauty care kits as well as other hardware tools, the annual production value of which reaches US$ 30 million dollars.

集团所属工厂主要生产多用钳、烤具、刀具、剪刀、厨具、花园工具、美容套等五金产品，年生产总值3000万美元，产品价廉物美、选料上乘、质量保证，深受国内外客户的青睐