Now showing items 21-40 of 461

(2010-06-10)
Audiovisual
Open Access
• #### Algebraic characterizations of distance-regular graphs ﻿

(Elsevier, 2002)
Article
Open Access
We survey some old and some new characterizations of distance-regular graphs, which depend on information retrieved from their adjacency matrix. In particular, it is shown that a regular graph with d+1 distinct eigenvalues ...
• #### Algebraic Characterizations of Regularity Properties in Bipartite Graphs ﻿

(2013)
Article
Restricted access - publisher's policy
Regular and distance-regular characterizations of general graphs are well-known. In particular, the spectral excess theorem states that a connected graph GG is distance-regular if and only if its spectral excess (a number ...
• #### Algorithmic problems about subgroups of free groups ﻿

(Universitat Politècnica de Catalunya, 2013-09)
Bachelor thesis
Open Access
The study of the lattice of subgroups of $F_{k}$ changed completely when J.Stallings published a paper that developed some special graphs in order to solve several algorithmic problems about subgroups like the membership ...
• #### Algorithms for the linear coloring arrangement problem ﻿

(Universitat Politècnica de Catalunya, 2015-01-28)
Bachelor thesis
Open Access
[CATALÀ] El projecte emprèn la tasca de desenvolupar algorismes eficients per resoldre o aproximar el problema de l'arranjament lineal mínim d'una coloració per a graphs, variació del MinLA. Aquí, l'assignació lineal està ...
• #### Algorithms for the restricted linear coloring arrangement problem ﻿

(Universitat Politècnica de Catalunya, 2019-07-04)
Bachelor thesis
Open Access
The aim of this project is to develop efficient algorithms for solving or approximating the Minimum Restricted Linear Coloring Arrangement Problem. It is the first approach to its algorithms, and we will face the problem ...
• #### Algorithms for the weighted independent domination problem ﻿

(Universitat Politècnica de Catalunya, 2019-07-04)
Bachelor thesis
Open Access
El problema de la dominació independent ponderada és un problema NP-hard d'optimització combinatòria en grafs. Aquest problema només ha estat abordat a la literatura per enfocaments de programació lineal entera, heurístiques ...
• #### Algunos grafos compuestos ﻿

Article
Open Access
From two graphs $G_1$ and $G_2$ on $N_1$ and $N_2$ vertices respectively, the compound graph $G_1[G_2]$ on $N_1N_2$ vertices is obtained connecting $N_2$ copies of $G_1$ following the structure of $G_2$. We present in ...
• #### Almost every tree with m edges decomposes K2m,2m ﻿

(2014-01)
Article
Open Access
We show that asymptotically almost surely a tree with m edges decomposes the complete bipartite graph K2m,2m, a result connected to a conjecture of Graham and Häggkvist. The result also implies that asymptotically almost ...
• #### A logic of graph conditions extended with paths ﻿

(2016)
Conference report
Open Access
In this paper we tackle the problem of extending the logic of nested graph conditions with paths. This means, for instance, that we may state properties about the existence of paths between some given nodes. As a main ...
• #### A logic of graph conditions extended with paths ﻿

(2016)
Conference report
Open Access
In this paper we tackle the problem of extending the logic of nested graph conditions with paths. This means, for instance, that we may state properties about the existence of paths between some given nodes. As a main ...
• #### A mathematical model for dynamic memory networks ﻿

(Iniciativa Digital Politècnica, 2011)
Conference report
Open Access
The aim of this paper is to bring together the work done several years ago by M.A. Fiol and the other authors to formulate a quite general mathematical model for a kind of permutation networks known as dynamic memories. A ...
• #### An algebraic approach to lifts of digraphs ﻿

(2018-12-07)
Article
Open Access
We study the relationship between two key concepts in the theory of (di)graphs: the quotient digraph, and the lift Ga of a base (voltage) digraph. These techniques contract or expand a given digraph in order to study its ...
• #### Anàlisi i similitud d'articles acadèmics utilitzant tècniques de llenguatge natural i xarxes neuronals ﻿

(Universitat Politècnica de Catalunya, 2019-01)
Bachelor thesis
Open Access
This project has reviewed the state of the art in natural language processing in order to extract the similarity between academic papers. In addition, analysis tools have been added in order to study the evolution of the ...
• #### Analysis of guifi.net's topology: extension of results ﻿

(2012-05-04)
External research report
Open Access
This report extends the analysis carried out in a previous work [1] about the topology of guifi.net wireless community network. The main objective is validating the topology generator proposed in [1] for guifi.net like ...
• #### Analysis of LDPC code syndrome entropy based on subgraphs ﻿

(Institute of Electrical and Electronics Engineers (IEEE), 2016)
Conference report
Restricted access - publisher's policy
We propose a method to bound the syndrome entropy of linear block codes from their factor graph representation. It is specially suited for sparse graphs such as those of low density parity check codes. It is based on the ...
• #### Analysis of Network Algorithms ﻿

(Universitat Politècnica de Catalunya, 2015-06)
Bachelor thesis
Restricted access - confidentiality agreement
Covenantee:  University of California, Irvine
• #### Analysis on distance metrics approaches in graphs and their applications ﻿

(Universitat Politècnica de Catalunya, 2019-07-05)
Master thesis
Restricted access - confidentiality agreement
• #### An eigenvalue characterization of antipodal distance-regular graphs ﻿

(1997-11)
Article
Open Access
Let $\Gamma$ be a regular (connected) graph with $n$ vertices and $d+1$ distinct eigenvalues. As a main result, it is shown that $\Gamma$ is an $r$-antipodal distance-regular graph if and only if the distance graph $\Gamma_d$ ...
• #### A new application of the $\otimes_h$-product to $\alpha$-labelings ﻿

(2015)
Article
Open Access
The weak tensor product was introduced by Snevily as a way to construct new graphs that admit a-labelings from a pair of known a-graphs. In this article, we show that this product and the application to a-labelings can be ...