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651.
Hypothesis testing for arbitrarily varying source (AVS), which is to decide between the two hypotheses for the varying behavior of the distribution of AVS, is considered in this paper. We determine the best asymptotic exponent of the second kind of error probability when the first kind of error probability is fixed. This result generalizes the well-known lemma of Stein in statistics. As a corollary, Strassen's coding theorem for AVS is obtained.Supported by the Young Teacher Foundation of Chinese Educational Ministry and by the National Natural Science Foundation of China.  相似文献   
652.
田震 《数学季刊》1993,8(3):50-51
This paper study the radical propertys in the sence of Amitsut and Kurosh fromreference[1].  相似文献   
653.
    
We use the matrix-valued Fejér–Riesz lemma for Laurent polynomials to characterize when a univariate shift-invariant space has a local orthonormal shift-invariant basis, and we apply the above characterization to study local dual frame generators, local orthonormal bases of wavelet spaces, and MRA-based affine frames. Also we provide a proof of the matrix-valued Fejér–Riesz lemma for Laurent polynomials.  相似文献   
654.
    
Let m(r, k) denote the minimum number of edges in an r‐uniform hypergraph that is not k‐colorable. We give a new lower bound on m(r, k) for fixed k and large r. Namely, we prove that if k ≥ 2n, then m(r, k) ≥ ?(k)kr(r/ln r)n/(n+1). © 2003 Wiley Periodicals, Inc. Random Struct. Alg., 2004  相似文献   
655.
    
Given graphs G and H, an edge coloring of G is called an (H,q)‐coloring if the edges of every copy of H ? G together receive at least q colors. Let r(G,H,q) denote the minimum number of colors in a (H,q)‐coloring of G. In 9 Erd?s and Gyárfás studied r(Kn,Kp,q) if p and q are fixed and n tends to infinity. They determined for every fixed p the smallest q (denoted by qlin) for which r(Kn,Kp,q) is linear in n and the smallest q (denoted by qquad) for which r(Kn,Kp,q) is quadratic in n. They raised the problem of determining the smallest q for which we have . In this paper by using the Regularity Lemma we show that if , then we have . © 2003 Wiley Periodicals, Inc. J Graph Theory 44: 39–49, 2003  相似文献   
656.
    
We consider bipartite subgraphs of sparse random graphs that are regular in the sense of Szemerédi and, among other things, show that they must satisfy a certain local pseudorandom property. This property and its consequences turn out to be useful when considering embedding problems in subgraphs of sparse random graphs. © 2003 Wiley Periodicals, Inc. Random Struct. Alg., 22: 359–434, 2003  相似文献   
657.
    
In this work, we study the structural stability of the fully implicit Euler scheme for the Brinkman‐Forchheimer equations. More precisely, we consider the time discretization scheme of the unsteady Brinkman–Forchheimer equations, and we prove the existence of solutions. Moreover, we derive somebia priori estimates of the discrete in time solutions. Next, with the aid of the discrete Gronwall lemma, we show that the numerical solutions depend continuously on the Brinkman and the Forchheimer coefficient. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
658.
    
A graph G with maximum degree Δ and edge chromatic number χ′(G)>Δ is edge‐Δ‐critical if χ′(G?e)=Δ for every edge e of G. It is proved here that the vertex independence number of an edge‐Δ‐critical graph of order n is less than . For large Δ, this improves on the best bound previously known, which was roughly ; the bound conjectured by Vizing, which would be best possible, is . © 2010 Wiley Periodicals, Inc. J Graph Theory 66:98‐103, 2011  相似文献   
659.
In this paper we consider a class of semilinear Schrödinger equation which terms are asymptotically periodic at infinity. Under a weaker superquadratic condition on the nonlinearity, the existence of a ground state solution is established. The main tools employed here to overcome the new difficulties are the concentration-compactness principle and the Local Mountain Pass Theorem.  相似文献   
660.
    
We prove that the vertex degree threshold for tiling (the 3‐uniform hypergraph with four vertices and two triples) in a 3‐uniform hypergraph on vertices is , where if and otherwise. This result is best possible, and is one of the first results on vertex degree conditions for hypergraph tiling.  相似文献   
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