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排序方式: 共有277条查询结果,搜索用时 15 毫秒
21.
Stefanie Gerke 《Discrete Mathematics》2007,307(13):1668-1671
The r-acyclic edge chromatic number of a graph G is the minimum number of colours required to colour the edges of G in such a way that adjacent edges receive different colours and every cycle C receives at least min{|C|,r} colours. We prove that for any integer r?4, the r-acyclic edge chromatic number of any graph G with maximum degree Δ and with girth at least 3(r-1)Δ is at most 6(r-1)Δ. 相似文献
22.
组合优化问题的定义[1]是定义1问题XYZ是指:对于每一个π(1)-集合S,从其诸π(2)-子集合中找出π(3)-(优)集合S*.本文直接从它出发,§§2-5讨论诸π(i)-集合(i=1,2,3)的某基本特性(property),公理(pos-tulate),或者特殊情形(particularcase).列出了一个清单PPP,叫做特性清单.它远非完善,但已经可以用来讨论不少问题.§6起简单地讨论若干个子清单,所对应的问题类,并讨论求解它们的一些方法. 相似文献
23.
24.
Colin McDiarmid 《Annals of Operations Research》1984,1(3):183-200
We discuss some results concerned with the behaviour of colouring algorithms on large random graphs. 相似文献
25.
H. D. Baecker 《BIT Numerical Mathematics》1970,10(4):405-414
The implications of the heap, reference variables and global generators in ALGOL 68 are examined and some notes on possible implementation mechanisms are presented. In particular the use or simulation of hardware with segment addressing facilities is discussed. 相似文献
26.
添加剂对不锈钢着色过程的影响 总被引:5,自引:0,他引:5
探讨了添加剂在不锈钢着色过程中的作用和影响,在特定条件下可使不锈钢成品获得满意的结果。 相似文献
27.
A.V. Nikitin S.N. Mikhailenko N.N. Filippov I. Morino R. Kumazawa 《Journal of Quantitative Spectroscopy & Radiative Transfer》2010,111(15):2211-2224
A methane spectral line list for the 5550-6236 cm−1 range with the intensity cut off 4×10−26 cm/molecule at 296 K is presented. The line list is based on new extensive measurements of methane spectral line parameters performed at different temperatures and pressures of methane and buffer gases N2, O2 and air. This spectral line list is prepared in HITRAN-2008 format and contains the following spectral line parameters of about 11,000 lines: position, intensity, energy for lower state (where possible), air-broadening and air-shifting coefficients, exponent of temperature dependence of air-broadening coefficient and self-broadening coefficient. 相似文献
28.
One way of defining an oriented colouring of a directed graph is as a homomorphism from to a target directed graph , and an injective oriented colouring of can be defined as a homomorphism from to a target directed graph such that no two in-neighbours of a vertex of have the same image. Oriented colourings may be constructed using target directed graphs that are nice, as defined by Hell et al. (2001). We extend the work of Hell et al. by considering target graphs that are tournaments, characterizing nice tournaments, and proving that every nice tournament on vertices is -nice for some . We also give a characterization of tournaments that are nice but not injective-nice. 相似文献
29.
Ewan Davies Rmi de Joannis de Verclos Ross J. Kang Franois Pirot 《Random Structures and Algorithms》2020,57(3):730-744
We prove two distinct and natural refinements of a recent breakthrough result of Molloy (and a follow‐up work of Bernshteyn) on the (list) chromatic number of triangle‐free graphs. In both our results, we permit the amount of color made available to vertices of lower degree to be accordingly lower. One result concerns list coloring and correspondence coloring, while the other concerns fractional coloring. Our proof of the second illustrates the use of the hard‐core model to prove a Johansson‐type result, which may be of independent interest. 相似文献
30.