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141.
Compact linearization for binary quadratic problems 总被引:1,自引:0,他引:1
Leo Liberti 《4OR: A Quarterly Journal of Operations Research》2007,5(3):231-245
We show that a well-known linearization technique initially proposed for quadratic assignment problems can be generalized
to a broader class of quadratic 0–1 mixed-integer problems subject to assignment constraints. The resulting linearized formulation
is more compact and tighter than that obtained with a more usual linearization technique. We discuss the application of the
compact linearization to three classes of problems in the literature, among which the graph partitioning problem.
相似文献
142.
Alexandre Delye de Clauzade de Mazieux Michel Marot Monique Becker 《Comptes Rendus Mecanique》2006,334(11):669-673
d-dominating sets in graphs are very important in system and network engineering. Their constructions is thus an important research topic. An heuristic which forms such sets by using a given criterion is proposed. We simplify the heuristic presented elsewhere. We extend it and prove the correctness of the extended heuristic. This heuristic has the advantage of being distributed and scalable. To cite this article: A. Delye de Clauzade de Mazieux et al., C. R. Mecanique 334 (2006). 相似文献
143.
Meng-xiao Yin 《应用数学学报(英文版)》2006,22(3):451-456
Let a(Kr,+1 - K3,n) be the smallest even integer such that each n-term graphic sequence п= (d1,d2,…dn) with term sum σ(п) = d1 + d2 +…+ dn 〉 σ(Kr+1 -K3,n) has a realization containing Kr+1 - K3 as a subgraph, where Kr+1 -K3 is a graph obtained from a complete graph Kr+1 by deleting three edges which form a triangle. In this paper, we determine the value σ(Kr+1 - K3,n) for r ≥ 3 and n ≥ 3r+ 5. 相似文献
144.
145.
给定一族图G,可定向曲面上存在多少个以其中某个图为基础图的标根地图?采用图的自同构群对图在可定向曲面上的嵌入集合进行分类,该文解决了这个问题,同时得到了求解计数函数f^r(M)的一种新的方法。 相似文献
146.
147.
The chromatic polynomial PG(q) of a loopless graph G is known to be non-zero (with explicitly known sign) on the intervals (−∞,0), (0,1) and (1,32/27]. Analogous theorems hold for the flow polynomial of bridgeless graphs and for the characteristic polynomial of loopless matroids. Here we exhibit all these results as special cases of more general theorems on real zero-free regions of the multivariate Tutte polynomial ZG(q,v). The proofs are quite simple, and employ deletion–contraction together with parallel and series reduction. In particular, they shed light on the origin of the curious number 32/27. 相似文献
148.
Following Alspach and Parsons, a metacirculant graph is a graph admitting a transitive group generated by two automorphisms ρ and σ, where ρ is (m,n)-semiregular for some integers m≥1, n≥2, and where σ normalizes ρ, cyclically permuting the orbits of ρ in such a way that σ
m
has at least one fixed vertex. A half-arc-transitive graph is a vertex- and edge- but not arc-transitive graph. In this article quartic half-arc-transitive metacirculants are explored
and their connection to the so called tightly attached quartic half-arc-transitive graphs is explored. It is shown that there
are three essentially different possibilities for a quartic half-arc-transitive metacirculant which is not tightly attached
to exist. These graphs are extensively studied and some infinite families of such graphs are constructed.
Both authors were supported in part by “ARRS – Agencija za znanost Republike Slovenije”, program no. P1-0285. 相似文献
149.
We show that the Priestley sum of finite trees contains no cyclic finite poset.
The first author would like to express his thanks for support from project LN 1M0021620808 of the Ministry of Education of
the Czech Republic. The second author would like to express his thanks for support from project 1M0021620808 of the Ministry
of Education of the Czech Republic, from the NSERC of Canada and from a PROF grant from the University of Denver. The third
author would like to express his thanks for the support from the NSERC of Canada and for partial support from the project
1M0021620808 of the Ministry of Education of the Czech Republic. 相似文献
150.
孙荣国 《高校应用数学学报(A辑)》1994,(3):335-337
本文给出了书本图B2m的m种不同的相继标号和B4m+1的m种不同的相继标号。因而,书本图Bm是相继图的充分条件为:m>1且m≠(3mod4)。这一条件也是书本图Bm是协调图的充要条件。 相似文献