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131.
A server needs to compute a broadcast schedule for n pages whose request times are known in advance. Outputting a page satisfies all outstanding requests for the page. The goal is to minimize the average waiting time of a client. In this paper, we show the equivalence of two apparently different relaxations that have been considered for this problem.  相似文献   
132.
In this article we prove the existence of the solution to the mixed problem for Euler–Bernoulli beam equation with memory term. The existence is proved by means of the Faedo–Galerkin method and the exponential decay is obtained by making use of the multiplier technique combined with integral inequalities due to Komornik. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
133.
Let d, k and n be three integers with k3, d4k−1 and n3k. We show that if d(x)+d(y)d for each pair of nonadjacent vertices x and y of a graph G of order n, then G contains k vertex-disjoint cycles converting at least min{d,n} vertices of G.  相似文献   
134.
多小波子空间上的单小波表示   总被引:1,自引:0,他引:1  
崔丽鸿  程正兴 《数学学报》2003,46(4):691-696
本文在较弱的条件下,建立了2重多小波子空间与单小波子空间的关系.即由2重多小波构造出单小波.一方面,这种单小波的平移伸缩与2重多小波的平移伸缩生成的子空间是完全相同的;另一方面,它具有插值性.因此通过构造出的单小波建立了多小波子空间上的Shannon型采样定理.  相似文献   
135.
Let X be a (real or complex) Banach space with dimension greater than 2 and let B0(X) be the subspace of B(X) spanned by all nilpotent operators on X. We get a complete classification of surjective additive maps Ф on B0(X) which preserve nilpotent operators in both directions. In particular, if X is infinite-dimensional, we prove that Ф has the form either Ф(T) = cATA^-1 or Ф(T) = cAT'A^-1, where A is an invertible bounded linear or conjugate linear operator, c is a scalar, T' denotes the adjoint of T. As an application of these results, we show that every additive surjective map on B(X) preserving spectral radius has a similar form to the above with |c| = 1.  相似文献   
136.
Jensen and Toft 8 conjectured that every 2‐edge‐connected graph without a K5‐minor has a nowhere zero 4‐flow. Walton and Welsh 19 proved that if a coloopless regular matroid M does not have a minor in {M(K3,3), M*(K5)}, then M admits a nowhere zero 4‐flow. In this note, we prove that if a coloopless regular matroid M does not have a minor in {M(K5), M*(K5)}, then M admits a nowhere zero 4‐flow. Our result implies the Jensen and Toft conjecture. © 2005 Wiley Periodicals, Inc. J Graph Theory  相似文献   
137.
In this paper, we evaluate various analytic Feynman integrals of first variation, conditional first variation, Fourier-Feynman transform and conditional Fourier-Feynman transform of cylinder type functions defined over Wiener paths in abstract Wiener space. We also derive the analytic Feynman integral of the conditional Fourier-Feynman transform for the product of the cylinder type functions which define the functions in a Banach algebra introduced by Yoo, with n linear factors.  相似文献   
138.
具有避难所的非自治竞争系统的持续生存和全局稳定性   总被引:2,自引:0,他引:2  
赵洪涌 《数学研究》1998,31(2):163-168
考虑一个四缀块模型,其中一缀块里有三个竞争种群,另外三个分别是它们的避难所,并且种群能在竞争缀块和各自的避难所间相互扩散.在一定的条件下,我们给出了此模型的持续生存,周期性和全局稳定性.  相似文献   
139.
The interactions of Cu(II) in Cu(II)-exchanged K-L gallosilicate with adsorbates containing coordinative nitrogens in ammonia, pyridine, aniline, acetonitrile and hydrazine, and with the adsorbates carbon monoxide, benzene, propanol and dimethyl sulfoxide are investigated by electron spin resonance (ESR) and electron spin echo modulation (ESEM) spectroscopies. These results are compared with those in Cu(II)-exchanged K-L aluminosilicate and the differences are discussed. Adsorption of ammonia produces a complex containing four molecules of ammonia based on resolved nitrogen superhyperfine interaction. Upon equilibrium with pyridine, Cu(II) forms a complex containing four molecules of pyridine in CuK-L gallosilicate and a complex containing only three molecules of pyridine in CuK-L aluminosilicate based on resolved nitrogen superhyperfine. Upon adsorption of aniline and acetonitrile, Cu(II) forms complexes containing two molecules of each in CuK-L gallosilicate based on resolved nitrogen superhyperfine. However, no resolved nitrogen superhyperfine between hydrazine and Cu(II) is seen. Adsorption of carbon monoxide, benzene, propanol and dimethyl sulfoxide causes changes in the ESR spectrum of Cu(II), indicating migration of Cu(II) into cation positions in the main channels where adsorbate coordination can occur. Cu(II) forms complexes with one molecule of benzene and two molecules of propanol based on ESEM data in both K-L gallosilicate and K-L aluminosilicate. However, Cu(II) interacts directly with one dimethyl sulfoxide in K-L aluminosilicate but only indirectly at a longer distance with one dimethyl sulfoxide in K-L gallosilicate based on ESEM data.  相似文献   
140.
设是可列非齐次马氏链,本文通过利用[1]中提出的在Wiener概率空间的一种实现,而给出了一个对任意可列非齐次马氏链普遍成立的强极限定理。  相似文献   
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