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61.
62.
<正>1引言在网络,自动化理论,差分方程求解及逻辑电路等实际问题中,往往需要求解分块带状方程组HX=F(1)这里H=(H_(ij)_(n×n),其中 相似文献
63.
J. X. Zhou 《Journal of Optimization Theory and Applications》1994,80(2):333-347
Let be an irreflexive (strict) binary relation on a nonempty setX. Denote the completion of by , i.e.,yx ifxy does not hold. An elementx
*
X is said to be a maximal element of onX ifx
*
x, xX. In this paper, an extension of the Zorn lemma to general nontrasitive binary relations (may lack antisymmetry) is established and is applied to prove existence of maximal elements for general nontrasitive (reflexive or irreflexive) binary relations on nonempty sets without assuming any topological conditions or linear structures. A necessary and sufficient condition has been also established to completely characterize the existence of maximal elements for general irreflexive nontrasitive binary relations. This is the first such result available in the literature to the best of our knowledge. Many recent known existence sults in the literature for vector optimization are shown to be special cases of our result.This work was supported in part by AFSOR Grant 91-0097.The author is grateful to the referees and Professor P. L. Yu for their comments and suggestions that led to this improved paper. 相似文献
64.
For the SOS model defined by the Hamiltonian
, where
x
,
x
,{1,2,...},h>0,x
d
,d2 it is shown that in the low-temperature region an infinite sequence of first-order phase transitions takes place whenh»0 and the temperature is fixed. 相似文献
65.
Isokinetic relationships of the series of electrophilic substitution reactions ofo-substituted phenylmercurials are studied, and the results show, for the first time, that isokinetic correlation analysis
can reveal the dominant factor in the system of the reactions. The analysis of SE2 ofo-substituted phenylmercuric chlorides indicates that the steric effect ofo-substituents is the predominant factor when I2 is used as electrophilic agent, however, the electronic effect ofo-substituents would become the predominant factor when HCl is used as the electrophilic agent. In SE1 ofo-substituted phenylmercuric chlorides, the results of the analysis display that the predominant factor is the field effects
ofo-substituents. The determination of predominant factors in those reactions would provide further scientific basis for those
reaction mechanisms. 相似文献
66.
In both the scalar quasi-massless SUSY breaking scenario and dilaton-dominant SUSY breaking scenario, we analyze experimental constraints to the parameter space in M theory compactified on S1/Z2. The sparticle spectrum and some phenomenological predictions are given. 相似文献
67.
具非零元素链二重几何平均对角占优矩阵 总被引:6,自引:0,他引:6
本文引进了具非零元素链二重几何平均对角占优矩阵的概念,讨论了它的性质及其与具非零元素链对角占优矩阵,非奇H-矩阵等的关系 相似文献
68.
Rounding Errors in Solving Block Hessenberg Systems 总被引:2,自引:0,他引:2
A rounding error analysis is presented for a divide-and-conquer algorithm to solve linear systems with block Hessenberg matrices. Conditions are derived under which the algorithm computes a stable solution. The algorithm is shown to be stable for block diagonally dominant matrices and for M-matrices.
69.
给出了判定非广义对角占优矩阵的充要条件,从理论上彻底解决了不可约非广义对角占优矩阵的判定问题,并给出了判定不可约非广义对角占优矩阵的具体算法. 相似文献
70.
N. V. Krylov 《Applied Mathematics and Optimization》2008,58(3):373-392
We discuss the possibility to represent smooth nonnegative matrix-valued functions as finite linear combinations of fixed
matrices with positive real-valued coefficients whose square roots are Lipschitz continuous. This issue is reduced to a similar
problem for smooth functions with values in a polyhedron.
The work was partially supported by NSF Grant DMS-0653121. 相似文献