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331.
A complete characterization of the extremal subsets of Hilbert spaces, which is an infinite-dimensional generalization of the classical Jung theorem, is given. The behavior of the set of points near the Chebyshev sphere of such a subset with respect to the Kuratowski and Hausdorff measures of noncompactness is investigated. 相似文献
332.
Let G be a graph, and g, f, f′ be positive integer-valued functions defined on V(G). If an f′-factor of G is a spanning tree, we say that it is f′-tree. In this paper, it is shown that G contains a connected (g, f+f′−1)-factor if G has a (g, f)-factor and an f′-tree.
Received: October 30, 2000 Final version received: August 20, 2002 相似文献
333.
本文在可度量化拓扑向量空间中建立了一个新的不动点定理 ,它部分推广了著名的 Tychonoff不动点定理 . 相似文献
334.
《Computational Geometry》2014,47(9):910-917
In this paper, we show that the θ-graph with three cones is connected. We also provide an alternative proof of the connectivity of the Yao graph with three cones. 相似文献
335.
We introduce quasi-convex subsets in Alexandrov spaces with lower curvature bound, which include not only all closed convex subsets without boundary but also all extremal subsets. Moreover, we explore several essential properties of such kind of subsets including a generalized Liberman theorem. It turns out that the quasi-convex subset is a nice and fundamental concept to illustrate the similarities and differences between Riemannian manifolds and Alexandrov spaces with lower curvature bound. 相似文献
336.
Yoshimi?Egawa Haruhide?MatsudaEmail author Tomoki?Yamashita Kiyoshi?Yoshimoto 《Graphs and Combinatorics》2008,24(1):13-18
Let k ≥ 2 be an integer. We show that if G is a (k + 1)-connected graph and each pair of nonadjacent vertices in G has degree sum at least |G| + 1, then for each subset S of V(G) with |S| = k, G has a spanning tree such that S is the set of endvertices. This result generalizes Ore’s theorem which guarantees the existence of a Hamilton path connecting
any two vertices.
Dedicated to Professor Hikoe Enomoto on his 60th birthday. 相似文献
337.
In this paper, we introduce a new class of generalized convex n-set functions, called (
, ρ,σ,θ)-V-Type-I and related non-convex functions, and then establish a number of parametric and semi-parametric sufficient optimality conditions for the primal problem under the aforesaid assumptions. This work partially extends an earlier work of [G.J. Zalmai, Efficiency conditions and duality models for multiobjective fractional subset programming problems with generalized (
, α, ρ, θ)-V-convex functions, Comput. Math. Appl. 43 (2002) 1489–1520] to a wider class of functions. 相似文献
338.
339.
In this paper, we present a new formulation for the local access network expansion problem. Previously, we have shown that this problem can be seen as an extension of the well-known Capacitated Minimum Spanning Tree Problem and have presented and tested two flow-based models. By including additional information on the definition of the variables, we propose a new flow-based model that permits us to use effectively variable eliminations tests as well as coefficient reduction on some of the constraints. We present computational results for instances with up to 500 nodes in order to show the advantages of the new model in comparison with the others. 相似文献
340.
多重积分的积分中值定理 总被引:3,自引:1,他引:2
利用开区域的道路连通性和一元连续函数的介值定理,在L ebesgue积分意义下证明了多重积分的积分中值定理. 相似文献