排序方式: 共有70条查询结果,搜索用时 15 毫秒
1.
通过构造几类图的最大独立集,给出了它们的分数染色数的下界;再通过构造具有该下界值的分数染色,给出了这几类循环图的分数染色数的上界,于是就确定了它们的分数染色数. 相似文献
2.
朱岩 《盐城师范学院学报》2008,28(1):111-114
郑玄是汉学的总结性人物,其《尚书》训诂,是东汉《尚书》学之代表。郑玄《尚书》训诂,融古文、今文、谶纬于一体,是两汉《尚书》学谶纬化范围扩大的最好例证。通过郑玄,我们可以知道,古今文《尚书》学的对立并不妨碍双方对谶纬的吸收,谶纬在郑玄手中变成整合古今文《尚书》学的桥梁。 相似文献
3.
Let G be a undirected connected graph. Given g groups each being a subset of V(G) and a number of colors, we consider how to find a subgroup of subsets such that there exists a tree interconnecting all
vertices in each subset and all trees can be colored properly with given colors (no two trees sharing a common edge receive
the same color); the objective is to maximize the number of subsets in the subgroup. This problem arises from the application
of multicast communication in all optical networks. In this paper, we first obtain an explicit lower bound on the approximability
of this problem and prove Ω(g1−ε)-inapproximability even when G is a mesh. We then propose a simple greedy algorithm that achieves performance ratio O√|E(G)|, which matches the theoretical bounds.
Supported in part by the NSF of China under Grant No. 70221001 and 60373012. 相似文献
4.
图的染色理论是图论的一个重要分支。本文使用分析的方法得到了轮和完全等二部图联图的全色数、均匀全色数和邻点可区别边色数。 相似文献
5.
Let k 5 be a fixed integer and let m = (k – 1)/2. It is shown that the independence number of a C
k-free graph is at least c
1[ d(v)1/(m – 1)](m – 1)/m
and that, for odd k, the Ramsey number r(C
k, K
n) is at most c
2(n
m + 1/log n)1/m
, where c
1 = c
1(m) > 0 and c
2 = c
2(m) > 0. 相似文献
6.
Vincenzo Cutello Giuseppe Nicosia Mario Pavone 《Journal of Combinatorial Optimization》2007,14(1):9-33
We present a new Immune Algorithm, IMMALG, that incorporates a Stochastic Aging operator and a simple local search procedure to improve the overall performances in
tackling the chromatic number problem (CNP) instances. We characterize the algorithm and set its parameters in terms of Kullback
Entropy. Experiments will show that the IA we propose is very competitive with the state-of-art evolutionary algorithms. 相似文献
7.
Bernard Gendron Alain Hertz Patrick St-Louis 《Journal of Combinatorial Optimization》2007,13(2):163-178
We consider the problem of orienting the edges of a graph so that the length of a longest path in the resulting digraph is
minimum. As shown by Gallai, Roy and Vitaver, this edge orienting problem is equivalent to finding the chromatic number of
a graph. We study various properties of edge orienting methods in the context of local search for graph coloring. We then
exploit these properties to derive four tabu search algorithms, each based on a different neighborhood. We compare these algorithms
numerically to determine which are the most promising and to give potential research directions. 相似文献
8.
吴电雷 《贵州民族学院学报》2011,(4):15-18
阳戏"三圣"指川主、土主、药王,他们是阳戏类型的标志。清吉镇宅、降福还愿是阳戏"三圣"信仰的宗旨。"三圣"由世间"人"向天上"神"的演化过程,浸润神秘性,并呈多样化的特点。文章采用文献阅读和田野调查结合的方法,对此问题进行探讨。 相似文献
9.
郭璞是两晋时期著名的文学家和杰出的训诂学家。受政治环境和文化思潮的影响,他创作了多首游仙诗以表达自己寄情仙境、向往自由的心绪,这也成为他显著的外相特征。而事实上,在其游仙诗中却蕴含着深厚的忧患意识,包括对国家命运的忧思,对黎民苦难的忧戚,对时光流逝、生命短暂、壮志难酬的忧伤感慨。 相似文献
10.
Wenan Zang 《Journal of Combinatorial Optimization》1998,2(2):117-188
A fully odd K4 is a subdivision of K4 such that each of the six edges of the K4 is subdivided into a path of odd length. In 1974, Toft conjectured that every graph containing no fully odd K4 can be vertex-colored with three colors. The purpose of this paper is to prove Toft's conjecture. 相似文献