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91.
Given a set of m identical bins of size 1, the online input consists of a (potentially infinite) stream of items in (0,1]. Each item is to be assigned to a bin upon arrival. The goal is to cover all bins, that is, to reach a situation where a total size of items of at least 1 is assigned to each bin. The cost of an algorithm is the sum of all used items at the moment when the goal is first fulfilled. We consider three variants of the problem, the online problem, where there is no restriction of the input items, and the two semi-online models, where the items arrive sorted by size, that is, either by non-decreasing size or by non-increasing size. The offline problem is considered as well. 相似文献
92.
Jing-wen Li Zhi-wen Wang Jaeun Lee Moo Young Sohn Zhong-fu Zhang En-qiang Zhu 《应用数学学报(英文版)》2010,26(3):525-528
In this paper we get some relations between α(G), α'(G), β(G), β'(G) and αT(G), βT(G). And all bounds in these relations are best possible, where α(G), α'(G),/3(G), β(G), αT(G) and βT(G) are the covering number, edge-covering number, independent number, edge-independent number (or matching number), total covering number and total independent number, respectively. 相似文献
93.
本文考虑随机区间In=ωn+(-en/2,en/2)(mod 1).利用文献[7]中所介绍的无处不在系统,证明了圆周上由被无穷次覆盖的点构成的集合的Hausdorff维数几乎必然等于min{1,lim sup n→∞ log n/-log en},推广了文献[4]中的结果. 相似文献
94.
Cheng Wang 《Applicable analysis》2013,92(7):1339-1349
The multi-class classification problem is considered by an empirical risk minimization (ERM) approach. The hypothesis space for the learning algorithm is taken to be a ball of a Banach space of continuous functions. When the regression function lies in some interpolation space, satisfactory learning rates for the excess misclassification error are provided in terms of covering numbers of the unit ball of the Banach space. A comparison theorem is proved and is used to bound the excess misclassification error by means of the excess generalization error. 相似文献
95.
We study the set covering polyhedron related to circulant matrices. In particular, our goal is to characterize the first Chvátal closure of the usual fractional relaxation. We present a family of valid inequalities that generalizes the family of minor inequalities previously reported in the literature. This family includes new facet-defining inequalities for the set covering polyhedron. 相似文献
97.
98.
Rosário Fernandes 《Linear and Multilinear Algebra》2013,61(8):977-991
We study the behaviour of the covering number of an element of a family of vectors under small perturbations. We apply this study to obtain results on the pairs of matrices that have the same immanent. 相似文献
99.
100.