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91.
We show that under perturbations by a rank-one typical operator, a fixed eigenvalue loses one Jordan block of maximal order, while the orders of the other Jordan blocks remain unchanged. We construct the first-order perturbation theory for the new eigenvalues and the zero-order approximations to the corresponding eigenvectors. 相似文献
92.
AN ALGORITHM FOR JORDAN CANONICAL FORM OF A QUATERNION MATRIX 总被引:2,自引:0,他引:2
In this paper, we first introduce a concept of companion vector, and study the Jordan canonical forms of quaternion matrices by using the methods of complex rep resentation and companion vector, not only give out a practical algorithm for Jordan canonical form J of a quaternion matrix A, but also provide a practical algorithm for corresponding nonsingular matrix P with P-1AP = J. 相似文献
93.
We characterize linear rank-k nonincreasing, rank-k preserving, and corank-k preserving maps on B(H), the algebra of all bounded linear operators on the Hilbert space H. This unifies and extends finite-dimensional results and results on linear rank-1 non-increasing and rank-1 preserving maps in the infinite-dimensional case. We conclude with an application to *-semigroup isomorphisms of operator ideals. 相似文献
94.
We study properties of Jordan representations ofH-dissipative operators in a finite-dimensional indefiniteH-space. An algebraic proof is given of the fact that such operators always have maximal semidefinite invariant subspaces.
Translated fromMatematicheskie Zametki, Vol. 63, No. 2, pp. 163–169, February, 1998.
The authors axe grateful to Professor A. A. Shkalikov for useful discussions.
The research of the first author was supported by INTAS under grant No. 93-0249. The research of the second author was supported
by the International Science Foundation and the Russian Government under grant No. NZP300. 相似文献
95.
从所周知,循环卷积和离散富里叶变换(DFT)可以互相计算,只要得到其中一个的快速算法就可导出另一个的快速算法。循环卷积目前已有乘法量为O(N)的最佳算法(特别是当N较小时),为此关键是如何将DFT转化为循环卷积,当DFT的长度N=p(p为素数),Rader利用有限域GF(p)的乘法群是循环群就成功地将p点DFT转化为Q(p)(F(p)为户的Euler函数)点循环卷积;当N=p~e时,由于商环Z/(p~e)存在F(p~c)阶元素,人们也成功地将p~c点DFT转化为P(p~(c-1))一系列循环卷积,即一个y(p~c)点循环卷积,二个P(p~(c-1))点 相似文献
96.
本文给出了一类带参数2n阶非对称微分算子Aλ的一些正则性定理,籍此可刻画一类飞行器在其运行过程中的双向平稳行为. 相似文献
97.
The bicompletion of an asymmetric normed linear space 总被引:5,自引:0,他引:5
A biBanach space is an asymmetric normed linear space (X,‖·‖) such that the normed linear space (X,‖·‖s) is a Banach space, where ‖x‖s= max {‖x‖,‖-x‖} for all x∈X. We prove that each asymmetric normed linear space (X,‖·‖) is isometrically isomorphic to a dense subspace of a biBanach space (Y,‖·‖Y). Furthermore the space (Y,‖·‖Y) is unique (up to isometric isomorphism).
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
98.
It is proved that for any Fuchsian group Γ such that ℍ/Γ is a hyperbolic Riemann surface, the Teichmüller curve V(Γ) has a unique complex manifold structure so that the natural projection of the Bers fiber space F(Γ) onto V(Γ) is holomorphic with local holomorphic sections. An isomorphism theorem for Teichmüller curves is deduced, which generalizes
a classical result that the Teichmüller curve V(Γ) depends only on the type of Γ and not on the orders of the elliptic elements of Γ when ℍ/Γ is a compact hyperbolic Riemann
surface. 相似文献
99.
Bo Kågström 《BIT Numerical Mathematics》1977,17(1):39-57
Some new types of bounds and perturbation bounds, based on the Jordan normal form, for the matrix exponential are derived. These bounds are compared to known bounds, both theoretically and by numerical examples. Some recent results on the matrix exponential and the logarithmic norm are also included. 相似文献
100.
设Gi是满足第二可数性公理的、Hausdorff的、顺从的、r-离散的、主的局部紧群胚,并且有一个紧开G-集覆盖;设Pi是Gi中含G_i ̄0的开闭集,且满足及相应的模是具有性质DC的C(Gi)的子代数(i=1,2).本文证明从A(P1)到A(P2)上的每一个等距代数同构可以扩张成从C(G1)到C(G2)上的C-同构,进一步,可以对C(G2)重新坐标化,使得这个C-同构可由一个群胚同构生成. 相似文献