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81.
本文研究了一类矩阵方程组解的秩的范围.利用矩阵的奇异值分解以及Frobenius范数的特征,得到了解的极值秩以及解的通式,并就这些问题的特殊情况进行了讨论,得到了一些结果. 相似文献
82.
设φ(z)=(φ1(z),…,φ_n(z))是D~n到自身的一个全纯映射,ψ(z)是D~n上的全纯函数,其中D~n是C~n中的单位多圆柱.研究了单位多圆柱上Bloch型空阊之间的加权复合算子ψC_φ的本性范数,并给出了其上下界估计. 相似文献
83.
In the paper we construct a system of bounded functions which generates an uncomplemented subspace in the Lorentz space Λ(α)
for all α∈(0,1). Lower bounds of the norms of the projector onto such subspaces are obtained.
Translated fromMatematicheskie Zametki, Vol. 68, No. 1, pp. 57–65, July, 2000. 相似文献
84.
85.
The successive approximation method was applied for the first time by N.I. Ioakimidis to solve practical cases of a Cauchy singular integral equation: the airfoil one. In this paper we study a more general case. We prove the convergence of the method in this general case. The proposed method has been tested for two kernels which are particularly important in practice. Finally, some numerical examples illustrate the accuracy of the method. 相似文献
86.
Constantin Popa 《BIT Numerical Mathematics》1999,39(2):323-338
In this paper we present an algorithm which, for a given (sparse) matrix, constructs a partition of its set of row-indices, such that each subset of this partition (except the last one obtained) contains indices which correspond to mutually orthogonal rows. We then use such decompositions in some classes of block-projections methods, previously extended by the author to general inconsistent linear least-squares problems. Numerical experiments on an inconsistent and rank-deficient least-squares model problem are described in the last section of the paper. 相似文献
87.
Teruhiro Shirakura 《Annals of the Institute of Statistical Mathematics》1986,38(1):145-159
Summary For a given fractional 2
m
factorial (2
m
-FF) designT, the constitution of a block plan to divideT intok (2
r−1<k≦2
r
) blocks withr block factors each at two levels is proposed and investigated. The well-known three norms of the confounding matrix are used
as measures for determining a “good” block plan. Some theorems concerning the constitution of a block plan are derived for
a 2
m
-FF design of odd or even resolution. Two norms which may be preferred over the other norm are slightly modified. For each
value ofN assemblies with 11≦N≦26, optimum block plans fork=2 blocks with block sizes [N/2] andN−[N/2] minimizing the two norms are presented forA-optimal balanced 24-FF designs of resolutionV given by Srivastava and Chopra (Technometrics,13, 257–269). 相似文献
88.
Dragan Vukoti? 《Journal of Mathematical Analysis and Applications》2005,311(1):377-380
A theorem and a corollary in the paper cited in the title were stated incorrectly, as was pointed out by Christopher Hammond. We now state correctly and prove both of them. These results still generalize and explain the geometric meaning of the Cowen-Hurst norm formula. We also include additional references and provide an example relevant for further study. 相似文献
89.
This paper deals with the class of continuous-time linear systems with Markovian jumps and multiple time delays. The systems that we are treating are assumed to have time-varying delays in their dynamics which can be different and also have uncertainties in the system parameters. The time-varying structure of the bounded uncertainties is considered. Delay-dependent conditions for stochastic stability and stochastic stabilizability and their robustness are considered. A design algorithm for a stabilizing memoryless controller is proposed. All the results are given in the LMI formalism. 相似文献
90.