Results 11 to 20 of about 39,621 (255)

Minor-Universal Graph for Graphs on Surfaces

open access: yesCoRR, 2023
We show that, for every n and every surface $Σ$, there is a graph U embeddable on $Σ$ with at most cn^2 vertices that contains as minor every graph embeddable on $Σ$ with n vertices. The constant c depends polynomially on the Euler genus of $Σ$. This generalizes a well-known result for planar graphs due to Robertson, Seymour, and Thomas [Quickly ...
Cyril Gavoille, Claire Hilaire
openaire   +2 more sources

MINORS IN WEIGHTED GRAPHS [PDF]

open access: yesBulletin of the Australian Mathematical Society, 2008
AbstractWe define the notion of minor for weighted graphs. We prove that with this minor relation, the set of weighted graphs is directed. We also prove that, given any two weights on a connected graph with the same total weight, we can transform one into the other using a sequence of edge subdivisions and edge contractions.
Joiţa, Cezar, Joiţa, Daniela
openaire   +1 more source

Small minors in dense graphs [PDF]

open access: yesEuropean Journal of Combinatorics, 2012
A fundamental result in structural graph theory states that every graph with large average degree contains a large complete graph as a minor. We prove this result with the extra property that the minor is small with respect to the order of the whole graph.
Samuel Fiorini   +3 more
openaire   +4 more sources

Modularity of minor‐free graphs

open access: yesJournal of Graph Theory, 2022
AbstractWe prove that a class of graphs with excluded minor and with the maximum degree of smaller order than the number of edges is maximally modular, that is, for every , the modularity of any graph in the class with sufficiently many edges is at least .
Michal Lason, Malgorzata Sulkowska
openaire   +2 more sources

The Minor Crossing Number of Graphs with an Excluded Minor [PDF]

open access: yesThe Electronic Journal of Combinatorics, 2008
The minor crossing number of a graph $G$ is the minimum crossing number of a graph that contains $G$ as a minor. It is proved that for every graph $H$ there is a constant $c$, such that every graph $G$ with no $H$-minor has minor crossing number at most $c|V(G)|$.
Bokal, Drago   +2 more
openaire   +5 more sources

The probability of planarity of a random graph near the critical point [PDF]

open access: yesDiscrete Mathematics & Theoretical Computer Science, 2013
Erdős and Rényi conjectured in 1960 that the limiting probability $p$ that a random graph with $n$ vertices and $M=n/2$ edges is planar exists. It has been shown that indeed p exists and is a constant strictly between 0 and 1.
Marc Noy   +2 more
doaj   +1 more source

Reconfiguration of graph minors

open access: yesCoRR, 2018
Under the reconfiguration framework, we consider the various ways that a target graph $H$ is a {\em minor} of a host graph $G$, where a subgraph of $G$ can be transformed into $H$ by means of {\em edge contraction} (replacement of both endpoints of an edge by a new vertex adjacent to any vertex adjacent to either endpoint).
Benjamin R. Moore   +2 more
openaire   +4 more sources

Complete graph minors and the graph minor structure theorem

open access: yesJournal of Combinatorial Theory, Series B, 2013
The graph minor structure theorem by Robertson and Seymour shows that every graph that excludes a fixed minor can be constructed by a combination of four ingredients: graphs embedded in a surface of bounded genus, a bounded number of vortices of bounded width, a bounded number of apex vertices, and the clique-sum operation.
Gwenaël Joret, David R. Wood
openaire   +3 more sources

Stem cell therapy for Crohn’s disease: systematic review and meta-analysis of preclinical and clinical studies

open access: yesStem Cell Research & Therapy, 2021
Background We explored whether stem cell therapy was effective for animal models and patients with Crohn’s disease (CD). Methods We searched five online databases. The relative outcomes were analyzed with the aid of GetData Graph Digitizer 2.26 and Stata
Ruo Wang   +7 more
doaj   +1 more source

Stochastic minority on graphs

open access: yesTheoretical Computer Science, 2011
Cellular automata have been mainly studied on very regular graphs carrying the vertices (like lines or grids) and under synchronous dynamics (all vertices update simultaneously). In this paper, we study how the asynchronism and the graph act upon the dynamics of the classical Minority rule.
Rouquier, Jean-Baptiste   +2 more
openaire   +4 more sources

Home - About - Disclaimer - Privacy