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991.
A System of Four Matrix Equations over von Neumann Regular Rings and Its Applications 总被引:3,自引:0,他引:3
QingWenWANG 《数学学报(英文版)》2005,21(2):323-334
We consider the system of four linear matrix equations A1X = C1, XB2=C2, A3XB3=C3 and A4XB4 = C4 over h, an arbitrary von Neumann regular ring with identity. A necessary and sufficient condition for the existence and the expression of the general solution to the system are derived. As applications, necessary and sufficient conditions are given for the system of matrix equations A1X = C1 and A3X=C3 to have a bisymmetric solution, the system of matrix equations A1X = C1 and A3XB3 = C3 to have a perselfconjugate solution over h with an involution and char h≠2, respectively. The representations of such solutions are also presented. Moreover, some auxiliary resultson other systems over h are obtained. The previous known results on some systems of matrix equations are special cases of the new results. 相似文献
992.
Semirings which are unions of rings 总被引:3,自引:0,他引:3
Sernirings which are a disjoint union of rings form a variety S which contains the variety of all rings and the variety of all idempotent sernirings, and in particular, the variety of distributive lattices. Various structure theorems are established which bring insight into the structure of the lattice of subvarieties of S.`` 相似文献
993.
In the paper bilateral shifts are studied which generate factorizations of unitary couplings (in the system theory they play the part of channels). Subspaces of L2(??), reducing the multiplication operator by eit, are investigated in the channel language. New criteria for regular divisibility of contractive operator functions in the class L∞ are obtained. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
994.
We study ideals in the space of entire functions of finite order and type on the plane. We obtain necessary and sufficient conditions for the ideal of functions vanishing at the common zeros of a system of N functions to be generated by the latter. 相似文献
995.
本文应用能量积分和解析半群的有关估计,研究广义二维Ginzburg-Landau方程 在Banach空间LP(Ω)的子空间X-α的指数吸引子. 相似文献
996.
997.
The solubilities of iodine from 9 to 30°C were measured in the C5, C6, C7, C8, and C10 cycloalkanes. The solubilities were found to increase smoothly with ring size and to be greater than these of corresponding n-alkane. The results are analyzed in terms of the solubility parameter version of the regular solution theory and, unlike the n-alkanes, good agreement is found suggesting that the cycloalkanes are good model substances for testing theoretical predictions of the effect of molecular size on the thermodynamics of liquid mixtures and that molecular shape and flexibility need not be considered, at least in equilibrium properties governed by the free energy. A similar analysis of the upper critical solution temperatures of cyloalkane + perfluorotributylamine, cycloalkane + perfluorocyclohexane, and n-alkane + perfluorotributylamine mixtures leads to the same conclusion. 相似文献
998.
M.M. Rao 《Journal of multivariate analysis》1975,5(3):330-413
A detailed study of the structure of conditional expectations and conditional probability measures is presented. Some characterizations of conditional expectations as a subclass of projection operators on Banach function spaces, and similarly conditional probabilities as a subclass of vector valued measures on such spaces are included. As applications of these results, a representation of Reynolds operators and related unified formulation of ergodic-martingale theorems are given. 相似文献
999.
1000.
江涛 《高校应用数学学报(A辑)》2003,18(1):77-80
设{Xκ,κ≥1}为一列独立同分布的非随机变量,且具有共同的分布函数F。记Sn为序列{Xκ,κ≥1}的前n项部分和。在F属于ERV分布族的假定下,文中证明了关于随机和SN(t)的随机中心化的精细大偏差结果。这里N(t)为一个与{Xκ,κ≥1}独立的非负整数值的随机过程。 相似文献