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1.
目前,广义逆在最优化中得到越来越多的应用,广义逆成了研究最优化的一个重要和有效的工具.最优化中的许多问题可以利用广义逆给出清晰、本质的表示.最优化中的病态问题(包括奇异性问题),可以通过考虑广义逆矩阵得到解决.本文按照作者的观点综述了广义逆矩阵在最优化各个领域中的应用.在本文中,我们用 R~m(C~m)表示 m 维向量空间,R~(m×n)(C~(m×n)表示 m×n 矩阵的  相似文献   

2.
广义极分解   总被引:9,自引:2,他引:7  
孙继广  陈春晖 《计算数学》1989,11(3):262-273
本文使用下列符号:C~(m×n)表示m×n复矩阵的集合,C_r~(m×n)表示秩为r的m×n复矩阵的集合,A~H和A~+分别表示矩阵A的共轭转置和Moore-Penrose广义逆,|| ||_2表示向量的Euclid范数和矩阵的谱范数,|| ||_F表示Frobenius范数,R(A)表示A的列  相似文献   

3.
实对称矩阵的两类逆特征值问题   总被引:84,自引:11,他引:84  
孙继广 《计算数学》1988,10(3):282-290
§gi.两类逆特征值问题先说明一些记号.R~(m×n)是所有m×n实矩阵的全体,R~n=R~(n×1),R=R~1;SR~(n×n)是 所有n×n实对称矩阵的全体;OR~(n×n)是所有n×n实正交矩阵的全体;I~((n))是n阶单位矩阵;A~T是矩阵A的转置;A>0表示A是正定的实对称矩阵.?(A)是矩阵A的列空间;A~+是矩阵A的Moore-Penrose广义逆;P_A=AA~+表示到?(A)的正交投影.λ(A)是A的特征值的全体;λ(K,M)是广义特征值问题K_x=λM_x的特征值的  相似文献   

4.
大型对称不定箭形线性方程组的分解方法   总被引:4,自引:1,他引:3  
1 引言 首先考虑2×2矩阵 显然当k>1/2时,矩阵K是对称正定的,且K可以分解成Cholesky因子:当k=1/2时,K为奇异矩阵;而当k<1/2时,K为对称不定矩阵,这时K有广义Cholesky分解式:并且这种分解是稳定的,一般地我们给出定义 定义1.1 设有矩阵K∈R~((m+n)×(m+n)),若总存在排列矩阵P∈R~((m+n)×(m+n))和对称正定矩阵H∈R~(m×n)、G∈R(m×m)使得则称矩阵K为对称拟定(Symmetric quasidefinite)矩阵。  相似文献   

5.
矩阵反问题解的稳定性   总被引:1,自引:0,他引:1  
孙继广 《计算数学》1986,8(3):251-257
首先说明一些记号.C~(m×n):所有m×n复元素矩阵的全体,C_r~(m×n):C~(m×n)中所有秩为r的矩阵的全体.A~H:矩阵A的转置共轭.I~((n)):n行列单位矩阵.A>0表示A是正定Hermite矩阵,λ_(max)(A)与λ_(min)(A)分别表示Hermite矩阵A的最大与最小特征值,σ_(max)(A)与σ_(min)(A)分别表示矩阵A的最大与最小奇异值.A~+:A的Moors-Penrose广义逆.|| ||_2:矩阵的谱范数,|| ||_F:矩阵的Frobenius范数.  相似文献   

6.
设矩阵方程为X_(m×n)A_(n×s)=B_(m×s) (1)本文运用矩阵的初等行变换给出了解矩阵方程(1)的一个简便方法。对于矩阵方程(1),我们给出了下面的定理1 矩阵方程(1)有解的充要条件是  相似文献   

7.
给定m×n阶矩阵A,我们给出了它的加边矩阵 为非奇的充分必要条件。其中O为r_1×r_2阶零矩阵。把M的逆矩阵记为分块形式 其中C_1为n×m、C_2为n×r_1、C_3为r_2×m、C_4为r_2×r_1阶矩阵。在一定条件下,我们证明了其中的C_1为A的广义逆矩阵A+。  相似文献   

8.
孙继广 《计算数学》1988,10(4):438-443
§1.引言 首先说明几个符号.R~(m×n)是所有m×n实矩阵的全体,R_r~(m×n)是R~(m×n)中秩为r的矩阵的全体,R~n=R~(n×1);A~T是矩阵A的转置,I~((n))是n×n单位矩阵,O是零矩阵;λ(Λ)是矩阵A的特征值的全体,|| ||_2是向量的欧氏范数和矩阵的谱范数,|| ||_F是矩阵的Frobenius范数; N(·)表示零空间.  相似文献   

9.
在文[1]的基础上,这篇注记给出了m×m复矩阵A的一类非奇异加边矩阵的特征,得到了利用这种加边矩阵的逆阵的子块求全体(1,2)-逆与Moors—Penrose逆所关联的两个定理。 本文约定:C~(m×n)表示m×n复矩阵的集合,C_r~(m×n)表示C~(m×n)的秩r的矩阵的子集,设A∈C~(m×n),通常把Penrose方程  相似文献   

10.
线性流形上的广义中心对称矩阵反问题   总被引:4,自引:0,他引:4  
袁永新  戴华 《计算数学》2005,27(4):383-394
设R∈Cn×n是满足R=RH=R-1≠±In的广义反射矩阵.若A∈Cn×n满足RAR=A,则称A为n阶广义中心对称矩阵,n阶广义中心对称矩阵的全体记为GCSCn×n.令X1,Z1∈Cn×k1,Y1,W1∈Cn×l1,S={A|‖AX1-Z1‖2+‖Y1HA-W1H‖2=min,A∈GCSCn×n},本文研究如下问题.问题Ⅰ.给定矩阵Z2,X2∈Cn×k2,Y2,W2∈Cn×l2,求A∈S,使得其中‖·‖是Frobenius范数.问题Ⅱ.给定矩阵A∈Cn×n,求A∈SE,使得其中SE是问题Ⅰ的解集合.本文给出了问题Ⅰ解集合SE的表达式,并导出了矩阵方程AX2=Z2,Y2HA=W2H有解A∈S的充分必要条件及其通解表达式,并给出了问题Ⅱ解的表达式以及求解问题Ⅱ的数值方法和数值例子.  相似文献   

11.
Some results are obtained for non-compact cases in topological vector spaces for the existence problem of solutions for some set-valued variational inequalities with quasi-monotone and lower hemi-continuous operators, and with quasi-semi-monotone and upper hemi-continuous operators. Some applications are given in non-reflexive Banach spaces for these existence problems of solutions and for perturbation problems for these set-valued variational inequalities with quasi-monotone and quasi-semi-monotone operators. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

12.
We introduce the notions of equiultimate boundedness and uniform ultimate boundedness with respect to part of the variables for solutions with partly controlled initial conditions. We obtain sufficient conditions for the equiultimate boundedness and uniform ultimate boundedness with respect to part of the variables of solutions with partly controlled initial conditions. We introduce the notions of equiboundedness and uniform boundedness with respect to part of the variables for solutions of systems with partly controlled initial conditions. We obtain sufficient conditions for the equiboundedness and uniform boundedness with respect to part of the variables of solutions with partly controlled initial conditions.  相似文献   

13.
14.
Atomistic equations of the electromagnetic field for a particle with spin are derived from a Lagrangian. These equations are consistent with the equations of motion for such a particle. The resulting phenomenological equations are the well-known equations of Maxwell for the electromagnetic field in matter. The atomistic field equations for a particle with spin and magnetic moment give a dipole field. This result and the corresponding quantum mechanics for a particle with spin are applied to compute the hyperfine structure of the hydrogen atom by perturbation theory.  相似文献   

15.
In this paper, vector variational inequalities (VVI) with matrix inequality constraints are investigated by using the image space analysis. Linear separation for VVI with matrix inequality constraints is characterized by using the saddle-point conditions of the Lagrangian function. Lagrangian-type necessary and sufficient optimality conditions for VVI with matrix inequality constraints are derived by utilizing the separation theorem. Gap functions for VVI with matrix inequality constraints and weak sharp minimum property for the solutions set of VVI with matrix inequality constraints are also considered. The results obtained above are applied to investigate the Lagrangian-type necessary and sufficient optimality conditions for vector linear semidefinite programming problems as well as VVI with convex quadratic inequality constraints.  相似文献   

16.
排序问题中优化准则关于基本参数的正则性及其应用   总被引:1,自引:0,他引:1  
本文提出了优化准则关于加工时间、准备时间、应交工时间的正则性,利用这种正则性对寻找参数可控排序问题中的有效值、有效解给出了一直观算法,并指出对一些具体的参数可控排序问题,其有效值、有效解的寻找可通过对这一直观算法加以具体化而得.文中还对平均流程问题给出了这样一个具体化算法.  相似文献   

17.
研究了化学分子图的Zagreb指标的逆问题,解决了对于给定的怎样的数存在分子图,其Zagreb指标值等于该数的问题,对n个顶点m条边的简单连通图,给出了其具有最小Zagreb指标值的充分必要条件,并给出了其具有最大Zagreb指标值的必要条件,为利用计算机搜索具有给定Zagreb指标值的所有分子图界定了顶点数和边数的范围,从而提高了计算机搜索的效率,这在组合化学中具有重要的意义。  相似文献   

18.
We consider stationary linear vector systems with commensurable delays. We obtain sufficient conditions for the reducibility of such systems to canonical form with the extraction of null dynamics. A constructive algorithm for the reduction of a system to that form is presented. We suggest a method for estimating the unknown input for vector delay systems with given accuracy.  相似文献   

19.
A periodic problem for the system of hyperbolic equations with finite time delay is investigated. The investigated problem is reduced to an equivalent problem, consisting the family of periodic problems for a system of ordinary differential equations with finite delay and integral equations using the method of a new functions introduction. Relationship of periodic problem for the system of hyperbolic equations with finite time delay and the family of periodic problems for the system of ordinary differential equations with finite delay is established. Algorithms for finding approximate solutions of the equivalent problem are constructed, and their convergence is proved. Criteria of well-posedness of periodic problem for the system of hyperbolic equations with finite time delay are obtained.  相似文献   

20.
隧洞围岩应力复变函数分析法中的解析函数求解   总被引:4,自引:3,他引:1       下载免费PDF全文
利用复变函数理论进行地下任意开挖断面隧洞围岩应力分析的前提,是根据围岩应力边界条件方程推导出两个解析函数.从Harnack定理出发,将隧洞围岩应力边界条件方程转化成积分方程;把Laurent级数有限项表示的映射函数引入积分方程中,将以任意开挖断面为边界条件的解析函数求解转化成以单位圆周线为边界条件的求解问题.对积分方程中各被积函数在讨论域内的解析性进行了分析,在此基础上利用留数理论求解了方程中各项积分值,并获得了用来表示任意开挖断面隧道围岩应力的两个解析函数通式.给出了圆形和椭圆形隧道的两个解析函数求解算例,所获得的结果与文献中的结果一致.利用留数理论推导出的两个解析函数通式,适用于任意开挖断面隧洞的围岩应力解析解的计算,且计算过程更为简单,计算结果更为精确.  相似文献   

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