甘油三脂与单纯性脂肪肝的相关分析

为探讨单纯性脂肪肝的发生与总胆固醇(TC)、甘油三脂(TG) 及血糖(PG)水平的关系.对583名离、退休人员进行全面体检,结合门诊病例资料进行横断面分析.结果显示TG及TG合并TC与脂肪肝的发病显著相关(P<0.01),而单纯TC或PG升高与单纯性脂肪肝无显著相关(P>0.05).从而得出单纯性脂肪肝的发病与高TG直接相关.     

An exact DSatur-based algorithm for the Equitable Coloring Problem

This paper describes an exact algorithm for the Equitable Coloring Problem, based on the well known DSatur algorithm for the classic Coloring Problem with new pruning rules specifically derived from the equity constraint. Computational experiences show that our algorithm is competitive with those known in literature.     

一类完全图生成的广义格子图的邻点可区别边染色

定义了一类2维广义格子图H2(G, n, m；k1, k2),并从图的结构出发,利用构造染色的方法,得到了图H2(K4, n, m；4,4)的邻点可区别边色数。     

(P~2)_n和(P~3)_n的D(3)-点可区别全染色

图的染色问题是图论研究的经典领域,在网络结构和实际生活中都有着广泛的应用,随着计算机和通讯、电力网络的日益发展,染色问题成为近年来图论研究的热点.图的D(β)-点可区别全染色又是染色问题中的难点.通过分类讨论、归纳探究,在图的点边集合与色集合间构造了一种一一对应关系.讨论了幂图Pkn(k=2,3)的点可区别全染色,使得距离不大于3(D(3))的任意2点都有不同的色集合,得到幂图Pkn(k=2,3)的D(3)-点可区别全染色数.     

On the determination and construction of optimal row-column designs having unequal row and column sizes

In this paper we consider experimental situations requiring usage of a row-column design where v treatments are to be applied to experimental units arranged in b ₁ rows and b ₂ columns where row i has size k _1i , i=1,..., b ₁ and column j has size k _2j , j=1,..., b ₂. Conditions analogous to those given in Kunert (1983, Ann. Statis., 11, 247–257) and Cheng (1978, Ann. Statist., 6, 1262–1272) are given which can often be used to establish the optimality of a given row-column design from the optimality of an associated block design. In addition, sufficient conditions are derived which guarantee the existence of an optimal row-column design which can be constructed by appropriately arranging treatments within blocks of an optimal block design.Visiting from the Indian Statistical Institute.     

On trees with a maximum proper partial 0-1 coloring containing a maximum matching

I prove that in a tree in which the distance between any two endpoints is even, there is a maximum proper partial 0-1 coloring such that the edges colored by 0 form a maximum matching.     

On star and caterpillar arboricity

We give new bounds on the star arboricity and the caterpillar arboricity of planar graphs with given girth. One of them answers an open problem of Gyárfás and West: there exist planar graphs with track number 4. We also provide new NP-complete problems.     

Graph Coloring with Adaptive Evolutionary Algorithms

This paper presents the results of an experimental investigation on solving graph coloring problems with Evolutionary Algorithms (EAs). After testing different algorithm variants we conclude that the best option is an asexual EA using order-based representation and an adaptation mechanism that periodically changes the fitness function during the evolution. This adaptive EA is general, using no domain specific knowledge, except, of course, from the decoder (fitness function). We compare this adaptive EA to a powerful traditional graph coloring technique DSatur and the Grouping Genetic Algorithm (GGA) on a wide range of problem instances with different size, topology and edge density. The results show that the adaptive EA is superior to the Grouping (GA) and outperforms DSatur on the hardest problem instances. Furthermore, it scales up better with the problem size than the other two algorithms and indicates a linear computational complexity.     

贪心染色下的随意可染色图

贪心算法用于图的染色问题是一种简单的近似方法.采用贪心算法,证明了将图G的顶点用独立集代替后所得的图GI是随意可染色的当且仅当G本身是随意可染色图;不含K2,3的三正则图是随意可染色图当且仅当它是K4.