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181.
This paper is based on the M. Sc. thesis written by the third author under the supervision of the first two authors. It was submitted to the University of Baghdad in 1986. 相似文献
182.
Our object of study is the asymptotic behavior of the sequence of polynomials orthogonal with respect to the discrete Sobolev
inner product <formula> \langle f, g \rangle = ∈t_{E} f(ξ) \overline{g(ξ)} ρ(ξ) |d ξ|+ f(Z) A g(Z)^H, </formula> where E is a rectifiable Jordan curve or arc in the complex plane
f(Z) = (f(z_1), \ldots, f^{(l_1)}(z_1) , \ldots , f(z_m) , \ldots ,f^{(l_m)}(z_m)),
A is an M \times M Hermitian matrix, M l
1
+ ⋅s + l
m
+ m , |d ξ| denotes the arc length measure, ρ is a nonnegative function on E , and z
i
∈Ω,
i=1,2,\ldots,m , where Ω is the exterior region to E .
July 23, 1999. Dates revised: September 11, 2000 and February 16, 2001. Date accepted: February 26, 2001. 相似文献
183.
Claire Cates Haulk John Drew Charles R. Johnson J. Hunter Tart 《Linear and Multilinear Algebra》1997,43(1):35-51
For a given n-by-n matrix A, we consider the set of matrices which commute with A and all of whose principal submatrices commute with the corresponding principal submatrices of A. The properties of this set are examined, with particular attention to its dimension. 相似文献
184.
相型同步启动时间的M/M/c排队系统 总被引:4,自引:0,他引:4
本文研究带有同步启动时间的M/M/c系统,其中启动时间是相型变量,给出了稳态和等待时间分布等结果。 相似文献
185.
Shu-Cheng Chang 《Mathematische Annalen》2002,324(3):465-490
In this paper, we consider the 2-dimensional local Calabi flow on a complete noncompact surface . Then, based on the Harnack-type estimate, we show the long-time existence and asymptotic convergence of a subsequence of
solutions of such a flow on with and bounded from above by a negative constant on a ball. For its applications, this will lead to the existence of extremal metrics
on a complete noncompact surface of finite topological type. In particular, there exists an extremal metric of nonconstant
Gaussian curvature on or
Received: 21 June 2001 / 18 January 2002 / Published online: 27 June 2002
Research supported in part by NSC and NCTS. 相似文献
186.
Guantie Deng 《Bulletin des Sciences Mathématiques》2007,131(1):53
In this paper, using a modified Poisson kernel in an upper half-space, we prove that a harmonic function u(z) in a upper half space with its positive part u+(x)=max{u(x),0} satisfying a slowly growing condition can be represented by its integral in the boundary of the upper half space, the integral representation is unique up to the addition of a harmonic polynomial, vanishing in the boundary of the upper half space and that its negative part u−(x)=max{−u(x),0} can be dominated by a similar slowly growing condition, this improves some classical result about harmonic functions in the upper half space. 相似文献
187.
188.
Let X be a Tychonoff space, C(X) be the space of all continuous real-valued functions defined on X and CL(X×R) be the hyperspace of all nonempty closed subsets of X×R. We prove the following result. Let X be a countably paracompact normal space. The following are equivalent: (a) dimX=0; (b) the closure of C(X) in CL(X×R) with the Vietoris topology consists of all F∈CL(X×R) such that F(x)≠∅ for every x∈X and F maps isolated points into singletons; (c) each usco map which maps isolated points into singletons can be approximated by continuous functions in CL(X×R) with the locally finite topology. From the mentioned result we can also obtain the answer to Problem 5.5 in [L'. Holá, R.A. McCoy, Relations approximated by continuous functions, Proc. Amer. Math. Soc. 133 (2005) 2173-2182] and to Question 5.5 in [R.A. McCoy, Comparison of hyperspace and function space topologies, Quad. Mat. 3 (1998) 243-258] in the realm of normal, countably paracompact, strongly zero-dimensional spaces. Generalizations of some results from [L'. Holá, R.A. McCoy, Relations approximated by continuous functions, Proc. Amer. Math. Soc. 133 (2005) 2173-2182] are also given. 相似文献
189.
Ronald Ortner 《Operations Research Letters》2007,35(5):619-626
In ergodic MDPs we consider stationary distributions of policies that coincide in all but n states, in which one of two possible actions is chosen. We give conditions and formulas for linear dependence of the stationary distributions of n+2 such policies, and show some results about combinations and mixtures of policies. 相似文献
190.
含氰基的酚醛树脂,具有优异的耐高温性能和高温下的机械强度,在315℃下性能变化甚小;不着火,发烟量低,有良好的加工成型性能。热固化过程中氰基成三嗪环而交联,没有小分子脱出,是一类具有广泛发展前景的新型热固性树脂。 相似文献