Now showing items 21-40 of 145

• Bijective enumeration of constellations in higher genus ﻿

(Universitat Politècnica de Catalunya, 2021-02-19)
Bachelor thesis
Open Access
Covenantee:   École Polytechnique Paris
Bousquet-Mélou i Schaeffer donaren el 2000 una enumeració bijectiva de certs mapes anomenats constel·lacions. El 2019, Lepoutre va descriure una bijecció entre mapes biacoloribles de gènere arbitrari i certs mapes unicel·lulars ...
• Binary labelings for plane quadrangulations and their relatives ﻿

(2010)
Article
Open Access
Motivated by the bijection between Schnyder labelings of a plane triangulation and partitions of its inner edges into three trees, we look for binary labelings for quadrangulations (whose edges can be partitioned into two ...
• c-Critical graphs with maximum degree three ﻿

(John Wiley and Sons, Inc., 1995)
Part of book or chapter of book
Restricted access - publisher's policy
Let $G$ be a (simple) gtoph with maximum degree three and chromatic index four. A 3-edge-coloring of G is a coloring of its edges in which only three colors are used. Then a vertex is conflicting when some edges incident ...
• Characterizations of classes of graphs by forbidden minors ﻿

(Universitat Politècnica de Catalunya, 2011)
Master thesis
Open Access
En aquest treball tractem el problema de descriure classes de grafs especificades per un menor prohibit. Concretament, presentem resultats de Wagner que caracteritzen grafs sense K5 o bé K3,3 com a menor. També donem ...
• Classical and modern approaches for Plünnecke-type inequalities ﻿

(Universitat Politècnica de Catalunya, 2015-09)
Bachelor thesis
Open Access
The main objective of this thesis is to present and prove Plünnecke's Inequality, a theorem that gives bounds for sumsets in commutative groups. An introduction to the theory of set addition is presented. Three different ...
• Combinatorial and analytic techniques for lattice path enumeration ﻿

(Universitat Politècnica de Catalunya, 2022-01)
Bachelor thesis
Open Access
This bachelor s degree thesis studies two type of combinatorial objects. The first ones are exact models of which we can get exact counting formulas, whereas the second type of models are the ones of which we don t have ...
• Combinatorics in the Art of the Twentieth Century ﻿

(2017)
Conference report
Open Access
This paper is motivated by a question I asked myself: How can combinatorial structures be used in a work of art? Immediately, other questions arose: Whether there are artists that work or think combinatorially? If so, what ...
• Combinatòria d'escales musicals i acords ﻿

(Universitat Politècnica de Catalunya, 2021-05)
Bachelor thesis
Open Access
En aquest treball es realitza un estudi de diferents conjunts i successions de notes musicals, com són les escales, els acords i les fileres de tons. Fent servir eines matemàtiques de la branca de la combinatòria es resolen ...
• Continued fractions, lattice paths and asymptotics ﻿

(Universitat Politècnica de Catalunya, 2021-02-18)
Bachelor thesis
Open Access
Covenantee:   Technische Universität Wien
Les fraccions contínues permeten descriure de forma natural les funcions generadores de camins etiquetats en una graella amb alçada fitada. Diversos problemes combinatoris presenten una bijecció natural amb aquests camins ...
• Convex quadrangulations of bichromatic point sets ﻿

(2020-06-05)
Article
Open Access
We consider quadrangulations of red and blue points in the plane where each face is convex and no edge connects two points of the same color. In particular, we show that the following problem is NP-hard: Given a finite set ...
• Corrigendum to"On the limiting distribution of the metric dimension for random forests" [European J. Combin. 49 (2015) 68-89] ﻿

(2017-07-22)
Article
Open Access
In the paper ”On the limiting distribution of the metric dimension for random forests” the metric dimension ß(G) of sparse G(n, p) with p = c/n and c < 1 was studied (Theorem 1.2). In the proof of this theorem, for the ...
• Coverage with k-transmitters in the presence of obstacles ﻿

(Springer Verlag, 2010)
Conference report
Restricted access - publisher's policy
For a fixed integer k ≥ 0, a k-transmitter is an omnidirectional wireless transmitter with an infinite broadcast range that is able to penetrate up to k “walls”, represented as line segments in the plane. We develop lower ...
• Decomposition of bounded degree graphs into C4-free subgraphs ﻿

(2014-10-15)
Article
Open Access
We prove that every graph with maximum degree ∆ admits a partition of its edges into O(√∆) parts (as ∆→∞) none of which contains C4 as a subgraph. This bound is sharp up to a constantfactor. Our proof uses an iterated ...
• Decomposition spaces in combinatorics ﻿

(2016-12)
Research report
Open Access
A decomposition space (also called unital 2-Segal space) is a simplicial object satisfying an exactness condition weaker than the Segal condition: just as the Segal condition expresses (up to homotopy) composition, the new ...
• Decompositions of a rectangle into non-congruent rectangles of equal area ﻿

(2021-06)
Article
Restricted access - publisher's policy
In this paper, we deal with a simple geometric problem: Is it possible to partition a rectangle into k non-congruent rectangles of equal area? This problem is motivated by the so-called ‘Mondrian art problem’ that asks a ...
• Digraphs with walks of equal length between vertices ﻿

(1984)
Conference report
Open Access
• Disecciones de un polígono en el plano proyectivo ﻿

Conference lecture
Restricted access - publisher's policy
En este trabajo obtenemos expresiones explícitas de las funciones generadoras de las triangulaciones y cuadrangulaciones del espacio topológico correspondiente a la supresión de un n-ágono del plano proyectivo real. En el ...
• Distance mean-regular graphs ﻿

(2016)
Article
Open Access
We introduce the concept of distance mean-regular graph, which can be seen as a generalization of both vertex-transitive and distance-regular graphs. Let G be a graph with vertex set V , diameter D, adjacency matrix A, and ...
• Does evidence support the high expectations placed in precision medicine? A bibliographic review ﻿

(2018-01-09)
Article
Open Access
Background: Precision medicine is the Holy Grail of interventions that aretailored to a patient’s individual characteristics.  However, the conventional design of randomized trials assumes that each individual benefits  ...
• DVALon: una herramienta para diagramas de Voronoi y grafos de proximidad de alcance limitado ﻿

(Prensas Universitarias de Zaragoza, 2009)
Conference report
Open Access
Presentamos un estudio de los diagramas de Voronoi de alcance limitado de un conjunto finito de puntos del plano y DVALon, una herramienta para la manipulaci´on de dichos diagramas, los grafos de proximidad de alcance ...