矩阵乘积行列式下界的改进

李耀堂和李继成[Joumal of Computational Mathematics，19(4)(2001)365-370]给出两个H-矩阵乘积的行列式的下界估计，应用我们所得的M-矩阵的Hadamard乘积的Oppenheim型不等式的新结论和方法，推广和改进了李耀堂和李继成的相应结论。     

非奇异H-矩阵的新判据

运用α-链对角占优矩阵的理论及Holder不等式的放缩技巧, 得到非奇异H-矩阵的几个新判据, 推广并改进了已有的对H-矩阵的判定方法, 并用数值算例说明了所给判定方法的有效性和优越性.     

SOME ESTIMATIONS FOR DETERMINANT OF THE HADAMARD PRODUCT OF H-MATRICES

In this paper,some new results on the estimations of bounds for determinant ofHadamard Product of two H-matrices are given.Several recent results are improved andgeneralized.     

非奇H-矩阵的充分条件

非奇H矩阵是具有广泛实际背景的重要矩阵类,但实际判断一个矩阵是否为非奇H矩阵却是困难的.该文给出非奇H矩阵的两个实用且适用范围较广的充分条件. 数值例子说明了结果的优越性.     

非奇H矩阵与M-矩阵的等价条件

本文引进了局部对角占优矩阵的概念，得到了非奇Ｈ矩阵与Ｍ－矩阵的等价条件与判定准则，改进了文［１］的主要结果．     

Convergence analysis of the parallel multisplitting TOR method

In this paper, we propose the parallel multisplitting TOR method, for solving a large nonsingular systems of linear equations Ax = b. These new methods are a generalization and an improvement of the relaxed parallel multisplitting method (Formmer and Mager, 1989) and parallel multisplitting AOR Algorithm (Wang Deren, 1991). The convergence theorem of this new algorithm is established under the condition that the coefficient matrix A of linear systems is an H-matrix. Some results also yield new convergence theorem for TOR method.     

A new criterion for the H-matrix property

For many applications, it is very useful to know whether a matrix is an H-matrix or not. Recently, some iterative tests have been proposed for distinguishing H-matrix. In this paper, we propose a new method for being able to distinguish only a scalar times column vector. Numerical evidence for the effectiveness of the proposed algorithm is presented.     

逆H矩阵的性质

研究了在理论和实际应用中有重要用途的H矩阵的相关问题．本文在文【3】给出的逆H矩阵定义的基础上，进一步得到了逆日矩阵的新的性质一对角元对于非对角元的占优关系．     

非奇H矩阵的简捷判据

本文给出了非奇Ｈ矩阵的充分条件及充分必要条件，改进了文（１）的相应结果。     

判别非奇异H阵的一个实用充分条件

目的寻求判别非奇异H阵的一个新的实用充分条件。方法对矩阵元素的比较。结果对文献[1,4]([1]干泰彬,黄廷祝.非奇异H矩阵的实用充分条件.计算数学,2004,26(1):109-116;[4]杨亚强,畅大为,李爱娟.一个非奇异H矩阵实用充分条件的改进.宝鸡文理学院学报:自然科学版,2005,25(3):161-164.)给出的非奇异H矩阵的实用充分条件进行改进,使得定理的适用范围明显扩大。结论对一些文献[1,4]不能判定的矩阵,该定理可以判定。