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51.
52.
We show a bridge principle for harmonic diffeomorphisms between closed surfaces with higher genus. 相似文献
53.
A random graph Gn(x) is constructed on independent random points U1,…,Un distributed uniformly on [0,1]d, d1, in which two distinct such points are joined by an edge if the l∞-distance between them is at most some prescribed value 0<x<1. The connectivity distance cn, the smallest x for which Gn(x) is connected, is shown to satisfy For d2, the random graph Gn(x) behaves like a d-dimensional version of the random graphs of Erdös and Rényi, despite the fact that its edges are not independent: cn/dn→1, a.s., as n→∞, where dn is the largest nearest-neighbor link, the smallest x for which Gn(x) has no isolated vertices. 相似文献
54.
Zofia Stepien/snm> 《Geometriae Dedicata》2002,93(1):37-45
We prove the formality property of any homogeneous space G/G
generated by an automorphism of finite order of a compact simple Lie group G. 相似文献
55.
Joshua N. Cooper Robert B. Ellis Andrew B. Kahng 《Journal of Combinatorial Theory, Series A》2002,100(2):232
An asymmetric binary covering code of length n and radius R is a subset
of the n-cube Qn such that every vector xQn can be obtained from some vector c
by changing at most R 1's of c to 0's, where R is as small as possible. K+(n,R) is defined as the smallest size of such a code. We show K+(n,R)Θ(2n/nR) for constant R, using an asymmetric sphere-covering bound and probabilistic methods. We show K+(n,n−
)=
+1 for constant coradius
iff n
(
+1)/2. These two results are extended to near-constant R and
, respectively. Various bounds on K+ are given in terms of the total number of 0's or 1's in a minimal code. The dimension of a minimal asymmetric linear binary code ([n,R]+-code) is determined to be min{0,n−R}. We conclude by discussing open problems and techniques to compute explicit values for K+, giving a table of best-known bounds. 相似文献
56.
57.
完备Brouwerian格上Fuzzy关系方程有极小解的条件 总被引:22,自引:0,他引:22
本文在有限论域上对完备Brouwerian格上Fuzzy关系方程极小的存在问题作了探讨,首先构造了Fuzzy关系方程有解但无极小解的一个例子,然后在解集非空时给出了对Fuzzy关系方程的每一个解都存在一个小于等于它的极小解的一个充分条件及一个充要条件,特别地,在充分条件下给出了一类Fuzzy关系方程所有极小解的个数的公式。 相似文献
58.
Johannes Wittmann 《Mathematische Nachrichten》2019,292(7):1627-1635
Let M be a closed spin manifold and let N be a closed manifold. For maps and Riemannian metrics g on M and h on N, we consider the Dirac operator of the twisted Dirac bundle . To this Dirac operator one can associate an index in . If M is 2‐dimensional, one gets a lower bound for the dimension of the kernel of out of this index. We investigate the question whether this lower bound is obtained for generic tupels . 相似文献
59.
60.
Pullback attractors of non-autonomous stochastic degenerate parabolic equations on unbounded domains
This paper is concerned with pullback attractors of the stochastic p -Laplace equation defined on the entire space Rn. We first establish the asymptotic compactness of the equation in L2(Rn) and then prove the existence and uniqueness of non-autonomous random attractors. This attractor is pathwise periodic if the non-autonomous deterministic forcing is time periodic. The difficulty of non-compactness of Sobolev embeddings on Rn is overcome by the uniform smallness of solutions outside a bounded domain. 相似文献