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131.
李相文 《数学物理学报(B辑英文版)》1998,(2)
1IntroductionWeuseBondyandMurtyl3]forterminologyand..ta'ti..notdefinedhereandconsidersimpleconnectedgraphsonly.AcircuitCofagraphGisanontrivialconnectedeuleriansubgraphofG.Aspanningcircuit,orbrieflyS-circuit,ofagraphGisacircuitthatcontainsallvenicesofG.AdominatingcircuitorD-circuitofGisacircuitsuchthateveryedgeofGisincidentwithatleastonevertexofthecircuit.AgraphofordernispancyclicifitcontainsallcyclesoflengthIfor3515n.IfCisacircuitofG,thenP(C)denotesthenumberOfedgesofGincidentwithatleas… 相似文献
132.
本文提出了求滚齿图形的解析方法,用该方法可以方便而精确地求出各种类型滚刀的切削图形,并能在计算机上直接打印出来。它既可以用来分析各种类型滚刀的切削过程,又可以作为滚刀计算机辅助设计的一个环节,以寻求更加高效和高耐用度的滚刀齿形。 相似文献
133.
程斌 《中央民族大学学报(自然科学版)》2005,14(3):209-213,240
本文通过分析三次图中面的奇偶性及组合情况,引出了可边三色块的概念,接着用面扩树方式给出了三次图中大量的可边三色块,在这些可边三色块中导出了三次图的一些边三色解. 相似文献
134.
135.
Robert W. Baddeley Cheryl E. Praeger Csaba Schneider 《Transactions of the American Mathematical Society》2006,358(4):1619-1641
A permutation group is innately transitive if it has a transitive minimal normal subgroup, which is referred to as a plinth. We study the class of finite, innately transitive permutation groups that can be embedded into wreath products in product action. This investigation is carried out by observing that such a wreath product preserves a natural Cartesian decomposition of the underlying set. Previously we classified the possible embeddings in the case where the plinth is simple. Here we extend that classification and identify several different types of Cartesian decompositions that can be preserved by an innately transitive group with a non-abelian plinth. These different types of decompositions lead to different types of embeddings of the acting group into wreath products in product action. We also obtain a full characterisation of embeddings of innately transitive groups with diagonal type into such wreath products.
136.
We are interested in improving the Varshamov bound for finite values of length n and minimum distance d. We employ a counting lemma to this end which we find particularly useful in relation to Varshamov graphs. Since a Varshamov
graph consists of components corresponding to low weight vectors in the cosets of a code it is a useful tool when trying to
improve the estimates involved in the Varshamov bound. We consider how the graph can be iteratively constructed and using
our observations are able to achieve a reduction in the over-counting which occurs. This tightens the lower bound for any
choice of parameters n, k, d or q and is not dependent on information such as the weight distribution of a code.
This work is taken from the author’s thesis [10] 相似文献
137.
Book embedding of graphs is one of the graph layout problem. It is useful for the multiprocessor network layout or the fault-tolerant processor arrays. We show that the trivalent Cayley graphs proposed by Vadapalli and Srimani can be embedded in five pages, and show some additional results on cube-connected cycles. 相似文献
138.
一个图G的全色数χT(G)是使得V(G)∪E(G)中相邻或相关联元素均染不同颜色的最少颜色数.文中证明了,若图G只有唯一的一个4度最大度点,则χT(G)=Δ(G)+1. 相似文献
139.
Klaus Ziegler 《Journal of multivariate analysis》1997,62(2):233-272
Functional central limit theorems for triangular arrays of rowwise independent stochastic processes are established by a method replacing tail probabilities by expectations throughout. The main tool is a maximal inequality based on a preliminary version proved by P. Gaenssler and Th. Schlumprecht. Its essential refinement used here is achieved by an additional inequality due to M. Ledoux and M. Talagrand. The entropy condition emerging in our theorems was introduced by K. S. Alexander, whose functional central limit theorem for so-calledmeasure-like processeswill be also regained. Applications concern, in particular, so-calledrandom measure processeswhich include function-indexed empirical processes and partial-sum processes (with random or fixed locations). In this context, we obtain generalizations of results due to K. S. Alexander, M. A. Arcones, P. Gaenssler, and K. Ziegler. Further examples include nonparametric regression and intensity estimation for spatial Poisson processes. 相似文献
140.
One of the central problems in the theory of ordered sets is to describe the orientations of the covering graph of an ordered set. We show that the particular operation called inversion, together with the classical constructions of retraction and product, provide a context for the classification of all such orientations.
AMS subject classifications (1980). 06A10, 05C75, 05C20. 相似文献