30 research outputs found
Перспективы развития фундаментальных наук. Т. 3 : Математика
Сборник содержит труды участников XVIII Международной конференции студентов, аспирантов и молодых учёных «Перспективы развития фундаментальных наук», представленные на секции «Математика». Предназначен для студентов, аспирантов, молодых ученых и преподавателей, специализирующихся в области математического моделирования и анализа данных, математических методов в физике, химии, биофизике, биологии, экономике, медицине, психологии, математической логики и приложений, вычислительной математики, а также дифференциальных уравнений
Catalogación en Formato Ibermarc
En este curso sobre catalogación se examinan las Reglas de Catalogación, el Formato Ibermarc, la catalogación de monografías del Catálogo de la Red de Bibliotecas del CSIC, la captación de registros a través de Z39.50 y el encabezamiento de autores personales
Close to regular multipartite tournaments
This thesis mainly deals with the existence of directed cycles and directed paths (or short: cycles and paths, respectively) with certain properties in close to regular multipartite tournaments. A multipartite tournament is an orientation of a complete multipartite graph. The statements in this thesis depend on how much a multipartite tournament differs from being regular. Chapters 2 to 4 consist of several results about cycles in multipartite tournaments: short cycles of a given length containing a given arc, cycles through a given arc and a given number of partite sets and cycles with a given number of vertices from each partite set. In Chapter 5 a bound of Yeo about the connectivity in close to regular multipartite tournaments is studied. Furthermore, in the last 3 chapters we look for paths in multipartite tournaments: paths containing a given number of vertices from each partite set, Hamiltonian paths and Hamiltonian paths containing a given arc
On the connectivity of close to regular multipartite tournaments
AbstractIf x is a vertex of a digraph D, then we denote by d+(x) and d-(x) the outdegree and the indegree of x, respectively. The global irregularity of a digraph D is defined by ig(D)=max{d+(x),d-(x)}-min{d+(y),d-(y)} over all vertices x and y of D (including x=y) and the local irregularity of a digraph D is il(D)=max|d+(x)-d-(x)| over all vertices x of D. Clearly, il(D)⩽ig(D). If ig(D)=0, then D is regular and if ig(D)⩽1, then D is almost regular.A c-partite tournament is an orientation of a complete c-partite graph. Let V1,V2,…,Vc be the partite sets of a c-partite tournament such that |V1|⩽|V2|⩽⋯⩽|Vc|. In 1998, Yeo provedκ(D)⩾|V(D)|-|Vc|-2il(D)3for each c-partite tournament D, where κ(D) is the connectivity of D. Using Yeo's proof, we will present the structure of those multipartite tournaments, which fulfill the last inequality with equality. These investigations yield the better boundκ(D)⩾|V(D)|-|Vc|-2il(D)+13in the case that |Vc| is odd. Especially, we obtain a 1980 result by Thomassen for tournaments of arbitrary (global) irregularity. Furthermore, we will give a shorter proof of the recent result of Volkmann thatκ(D)⩾|V(D)|-|Vc|+13for all regular multipartite tournaments with exception of a well-determined family of regular (3q+1)-partite tournaments. Finally we will characterize all almost regular tournaments with this property
CYCLES THROUGH A GIVEN SET OF VERTICES IN REGULAR MULTIPARTITE TOURNAMENTS
A tournament is an orientation of a complete graph, and in general a multipartite or c-partite tournament is an orientation of a complete c-partite graph. In a recent article, the authors proved that a regular c-partite tournament with r ≥ 2 vertices in each partite set contains a cycle with exactly r − 1 vertices from each partite set, with exception of the case that c = 4 and r = 2. Here we will examine the existence of cycles with r −2 vertices from each partite set in regular multipartite tournaments where the r − 2 vertices are chosen arbitrarily. Let D be a regular c-partite tournament and let X ⊆ V (D) be an arbitrary set with exactly 2 vertices of each partite set. For all c ≥ 4 we will determine the minimal value g(c) such that D−X is Hamiltonian for every regular multipartite tournament with r ≥ g(c)
Almost regular c-partite tournaments with ²c ge 8² contain an n-cycle through a given arc for ²4 le n le c²
Almost regular multipartite partite tournaments containing a Hamiltonian path through a given arc
Особенности разработки нефтяной залежи фундамента месторождения "Белый Тигр" (Вьетнам)
Приведены общие сведения о структуре, литолого- петрографической характеристике фундамента месторождения Белый Тигр. Проанализированы основные особенности разработки Центрального блока фундамента этого месторождении, приведены новые схемы и технологии разработки залежи нефти фундамента, которые являются предпосылкой для проектирования и разработки других подобных нефтяных месторождений с залежами в магматическом фундаменте.The main features and problems of the development of the central block of the basement at the White Tiger (Vietnam) deposit wаs considered and analyzed in the thesis, as well as new schemes and technologies for the development of the oil basement