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461.
矩阵Frobenius范数不等式 总被引:1,自引:0,他引:1
1 引言与引理 矩阵范数与矩阵奇异值问题是数值代数的重要课题,并在矩阵扰动分析,数值计算等分支中起着重要作用.国内外学者对此已作了大量研究. 相似文献
462.
An interesting connection between special sets of the Hermitian surface of PG(3,q2), q odd, (after Shult 13 ) and indicator sets of line‐spreads of the three‐dimensional projective space is provided. Also, the CP‐type special sets are characterized. © 2007 Wiley Periodicals, Inc. J Combin Designs 16: 18–24, 2008 相似文献
463.
We present improved lower bounds on the sizes of small maximal partial ovoids in the classical hermitian polar spaces, and
improved upper bounds on the sizes of large maximal partial spreads in the classical hermitian polar spaces. Of particular
importance is the presented upper bound on the size of a maximal partial spread of H(3,q
2). For q = 2,3, the presented upper bound is sharp. For q = 3, our results confirm via theoretical arguments properties, deduced by computer searches performed by Ebert and Hirschfeld,
for the largest partial spreads of H(3,9). An overview of the status regarding these results is given in two summarizing tables. The similar results for the classical
symplectic and orthogonal polar spaces are presented in De Beule et al. [8].
相似文献
464.
Enrico Boasso 《Journal of Mathematical Analysis and Applications》2008,339(2):1003-1014
The main concern of this note is the Moore-Penrose inverse in the context of Banach spaces and algebras. Especially attention will be given to a particular class of elements with the aforementioned inverse, namely EP Banach space operators and Banach algebra elements, which will be studied and characterized extending well-known results obtained in the frame of Hilbert space operators and C∗-algebra elements. 相似文献
465.
In this paper, we consider a linear restriction problem of Hermitian reflexive matrices and its approximation. By using the properties and structure of Hermitian reflexive matrices and the special properties of reflexive vectors and anti-reflexive vectors, we convert the linear restriction problem to an equivalence problem trickily, which is a special feature of this paper and is a different method from other articles. Then we solve this problem completely and also obtain its optimal approximate solution. Moreover, an algorithm provided for it and the numerical examples show that the algorithm is feasible. 相似文献
466.
Thomas Borek 《Journal of Number Theory》2005,113(2):380-388
The purpose of this paper is to clarify the relationship between the successive minima and the slopes of a hermitian vector bundle on the spectrum of the ring of integers of an algebraic number field. The main result is a lower and an upper bound for each successive minimum in terms of the corresponding slope. 相似文献
467.
Several splittings for non-Hermitian linear systems 总被引:3,自引:0,他引:3
Zhong-Zhi Bai 《中国科学A辑(英文版)》2008,51(8):1339-1348
For large sparse non-Hermitian positive definite system of linear equations,we present several variants of the Hermitian and skew-Hermitian splitting(HSS)about the coefficient matrix and establish correspondingly several HSS-based iterative schemes.Theoretical analyses show that these methods are convergent unconditionally to the exact solution of the referred system of linear equations,and they may show advantages on problems that the HSS method is ineffiective. 相似文献
468.
469.
Adam Korányi 《Journal of Functional Analysis》2008,254(9):2419-2436
In this paper we construct a large class of multiplication operators on reproducing kernel Hilbert spaces which are homogeneous with respect to the action of the Möbius group consisting of bi-holomorphic automorphisms of the unit disc D. Indeed, this class consists of exactly those operators for which the associated unitary representation of the universal covering group of the Möbius group is multiplicity free. For every m∈N we have a family of operators depending on m+1 positive real parameters. The kernel function is calculated explicitly. It is proved that each of these operators is bounded, lies in the Cowen-Douglas class of D and is irreducible. These operators are shown to be mutually pairwise unitarily inequivalent. 相似文献
470.
Robin Harte 《Journal of Mathematical Analysis and Applications》2008,347(1):370-374
The Fuglede property extends to ∗-hyponormal Banach algebra elements, and certain Banach algebra elements are approximated by self-commutators. 相似文献