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951.
Hurewicz-Radon theorem [1] gives a sufficient and necessary condition about the existence of an orthogonal multiplication f:Rk×Rn→Rn. In this paper,we shall discuss two extensions of the theorem.that is,the sufficient and necessary conditions about the existence of an orthogonal multiplication f:Rk×Rn→Rn 1or f:Rk×Rn→Rn 2 相似文献
952.
This paper is an investigation of the structural properties of random plane-oriented recursive trees and their branches. We begin by an enumeration of these trees and some general properties related to the outdegrees of nodes. Using generalized Pólya urn models we study the exact and limiting distributions of the size and the number of leaves in the branches of the tree. The exact distribution for the leaves in the branches is given by formulas involving second-order Eulerian numbers. A martingale central limit theorem for a linear combination of the number of leaves and the number of internal nodes is derived. The distribution of that linear combination is a mixture of normals with a beta distribution as its mixing density. The martingale central limit theorem allows easy determination of the limit laws governing the leaves in the branches. Furthermore, the asymptotic joint distribution of the number of nodes of outdegree 0, 1 and 2 is shown to be trivariate normal. © 1993 John Wiley & Sons, Inc. 相似文献
953.
V. Papathanasiou 《Journal of multivariate analysis》1996,58(2):189-196
Multivariate variational inequalities are obtained in terms of thew-functions and the trace of a Fisher-type information matrix. In consequence of these inequalities, the multivariate central limit theorem arises in the sense of the total variation. 相似文献
954.
半导体物理中的一个两点边值问题 总被引:2,自引:0,他引:2
本文研究了在半导体流的区域提纯过程中提出的两点边值问题解的存在性,我们用上、下解方法和Sshauder不动点定理证明了如果Q=2A3Re,其中A是表面速率,Re是Reynolds数,则当0 Q 12.68时,该问题有解. 对[1]的结果(0 Q<8.51时,此问题的解存在)进行了重要的改进. 相似文献
955.
Kotarski W.; El-Saify H. A.; Bahaa G. M. 《IMA Journal of Mathematical Control and Information》2002,19(4):461-476
A distributed control problem for the parabolic operator withan infinite number of variables and time delay is considered.The performance index has an integral form. Constraints on controlsare imposed. To obtain optimality conditions for the Neumannproblem, the generalization of the DubovitskiiMilyutintheorem given by Walczak in WALCZAK, S. Folia Mathematics, 1,187196 and WALCZAK, S. J. Optim. Theory Appl., 42, 561582was applied. 相似文献
956.
957.
MoJIAQI 《高校应用数学学报(英文版)》1997,12(3):287-292
Singularly perturbed problems for the nonlinear dliptie systems in a strip domain are considered. Under suitabla conditions, by using the comparison theorem, the existence andasymptotic behavior of solution for the boundary value problems are studied. 相似文献
958.
We continue the study of quantum matrix algebras of the GL(m|n) type. We find three alternative forms of the Cayley-Hamilton identity; most importantly, this identity can be represented
in a factored form. The factorization allows naturally dividing the spectrum of a quantum supermatrix into subsets of “even”
and “odd” eigenvalues. This division leads to a parameterization of the characteristic subalgebra (the subalgebra of spectral
invariants) in terms of supersymmetric polynomials in the eigenvalues of the quantum matrix. Our construction is based on
two auxiliary results, which are independently interesting. First, we derive the multiplication rule for Schur functions s
λ
(M) that form a linear basis of the characteristic subalgebra of a Hecke-type quantum matrix algebra; the structure constants
in this basis coincide with the Littlewood-Richardson coefficients. Second, we prove a number of bilinear relations in the
graded ring Λ of symmetric functions of countably many variables.
__________
Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 147, No. 1, pp. 14–46, April, 2006. 相似文献
959.
倒向随机微分方程由Pardoux和彭实戈首先提出,彭实戈给出了一维BSDE的比较定理,周海滨将其推广到了高维情形.毛学荣将倒向随机微分方程解的存在唯一性定理推广到非Lipschitz系数情况,曹志刚和严加安给了相应的一维比较定理.本文将曹志刚和严加安的比较定理推广到高维情形. 相似文献
960.
In this paper, we extend the Hölderian invariance principle of Lamperti [6] to the case of partial-sum processes based on a triangular array of row-wise independent random variables. As an application, we obtain necessary and sufficient conditions for the almost sure (resp. in probability) weak Hölder convergence of partial-sum processes based on bootstrapped samples. 相似文献