Now showing items 1-20 of 22

    • A note on flips in diagonal rectangulations 

      Cardinal, Jean; Sacristán Adinolfi, Vera; Silveira, Rodrigo Ignacio (Chapman & Hall/CRC, 2018-11-09)
      Article
      Open Access
      Rectangulations are partitions of a square into axis-aligned rectangles. A number of results provide bijections between combinatorial equivalence classes of rectangulations and families of pattern-avoiding permutations. ...
    • A study of the threshold selection in the Linear Threshold Rank for random social networks 

      Iacovissi, Laura (Universitat Politècnica de Catalunya, 2020-07)
      Master thesis
      Restricted access - author's decision
      An influence network is a directed graph with edge weights and node thresholds. Influence spreads starting from X=S. When the sum of the weights of the incoming arcs from X overpasses a node threshold it is added to X. The ...
    • A traffic simulation tool for assessing smart city policies (CitScale) 

      Linares Herreros, María Paz; Montero Mercadé, Lídia; Casanovas Garcia, Josep (2019-09-28)
      Article
      Restricted access - publisher's policy
      Over the last century, cities have developed as a function of increased usage of automobiles as the standard transport mode. The number of cars increased along with the population as highways and parking spots became ...
    • Bounded expansion in models of webgraphs 

      Gago Álvarez, Silvia; Schlatter, Dirk (2007-10-02)
      Article
      Open Access
      We study the bounded expansion of several models of web graphs. We show that various deterministic graph models for large complex networks have constant bounded expansion.We study two random models of webgraphs, showing ...
    • Comunitats en xarxes complexes: detecció i centralitat 

      Quintana Mathé, Alexi (Universitat Politècnica de Catalunya, 2017-07)
      Bachelor thesis
      Open Access
      En aquest treball estudiem l'estructura de comunitats en xarxes complexes. S'anomenen xarxes complexes als grafs construïts a partir de dades empíriques complint una sèrie de propietats, i s'entén per comunitat en un xarxa ...
    • Empowering teachers' self assessment of their own practice on student's oral skills: EVALOE decision support system 

      Grácia, M.; Casanovas Garcia, Josep; Sancho Samsó, María Ribera; Casanovas Muñoz, Jordi; Cuatrecasas Capdevila, Marta (Scitepress, 2018)
      Conference report
      Restricted access - publisher's policy
      School is an essential context that contributes to children's communicative competence. Decision Support Systems (DSS) are tools that can help teachers to assess their own practice and to make decisions to improve it (Gregg, ...
    • Encapsulated PGD algebraic toolbox operating with high-dimensional data 

      Díez, Pedro; Zlotnik, Sergio; García González, Alberto; Huerta, Antonio (2019-11-28)
      Article
      Restricted access - publisher's policy
      In its original conception, proper generalized decomposition (PGD) provides explicit parametric solutions, denoted as computational vademecums or digital abacuses, to parametric boundary value problems. The PGD approach ...
    • Extraction of threshold functions from formulas in propositional logic 

      Milesi Vidal, Eric (Universitat Politècnica de Catalunya, 2017-01)
      Bachelor thesis
      Restricted access - author's decision
      Given a formula in propositional logic F in some presentation (BDD, ROBDD, truth table), our aim is to find a threshold function T that is a logical consequence of F and that is as strong as possible according to certain ...
    • Isogeny-based post-quantum key exchange protocols 

      Sorinas Capdevila, Ernest (Universitat Politècnica de Catalunya, 2020-01)
      Bachelor thesis
      Open Access
      The goal of this project is to understand and analyze the supersingular isogeny Diffie Hellman (SIDH), a post-quantum key exchange protocol which security lies on the isogeny-finding problem between supersingular elliptic ...
    • K-1,K-3-covering red and blue points in the plane 

      Ábrego, Bernardo M.; Fernández Merchant, Silvia; Kano, Mikio; Orden, David; Pérez Lantero, Pablo; Seara Ojea, Carlos; Tejel Altarriba, Francisco Javier (Chapman & Hall/CRC, 2019-01-31)
      Article
      Open Access
      We say that a finite set of red and blue points in the plane in general position can be K1,3-covered if the set can be partitioned into subsets of size 4, with 3 points of one color and 1 point of the other color, in such ...
    • Logaritme discret i aplicacions a la criptografia 

      Ferrer Fernàndez, Sergi (Universitat Politècnica de Catalunya, 2015-07)
      Bachelor thesis
      Open Access
      El logaritme discret és un isomorfisme entre el grup de les classes de congruència mòdul n i el grup G. Aquesta aplicació és molt útil per a crear protocols criptogràfics de clau pública. La seguretat d'aquests sistemes ...
    • Nonintrusive proper generalised decomposition for parametrised incompressible flow problems in OpenFOAM 

      Tsiolakis, Vasileios; Giacomini, Matteo; Sevilla Cárdenas, Rubén; Othmer, Carsten; Huerta, Antonio (2020-04)
      Article
      Restricted access - publisher's policy
      The computational cost of parametric studies currently represents the major limitation to the application of simulation-based engineering techniques in a daily industrial environment. This work presents the first nonintrusive ...
    • Online coloring problem with a randomized adversary and infinite advice 

      Burjons Pujol, Elisabet (Universitat Politècnica de Catalunya, 2015-07)
      Master thesis
      Open Access
      Online problems are those in which the instance is not given as a whole but by parts named requests. They arrise naturaly in computer science. Several examples are given such as ski rental problem, the server problem and ...
    • Quantification of network structural dissimilarities 

      Schieber, Tiabo A.; Carpi, Laura; Díaz Guilera, Albert; Pardalos, Panos M.; Masoller Alonso, Cristina; Ravetti, Martin G. (2017-01-09)
      Article
      Open Access
      Identifying and quantifying dissimilarities among graphs is a fundamental and challenging problem of practical importance in many fields of science. Current methods of network comparison are limited to extract only partial ...
    • Rainbow spanning subgraphs in bounded edge–colourings of graphs with large minimum degree 

      Cano Vila, María del Pilar; Perarnau Llobet, Guillem; Serra Albó, Oriol (2017-08-01)
      Article
      Open Access
      We study the existence of rainbow perfect matching and rainbow Hamiltonian cycles in edge–colored graphs where every color appears a bounded number of times. We derive asymptotically tight bounds on the minimum degree of ...
    • Secret sharing schemes: Optimizing the information ratio 

      Hernández Ansuátegui, Félix (Universitat Politècnica de Catalunya, 2017-07)
      Bachelor thesis
      Open Access
      Secret sharing refers to methods used to distribute a secret value among a set of participants. This work deals with the optimization of two parameters regarding the efficiency of a secret sharing scheme: the information ...
    • Self-similar non-clustered planar graphs as models for complex networks 

      Comellas Padró, Francesc de Paula; Zhang, Zhongzhi; Chen, Lichao (2008-10-10)
      Article
      Open Access
      In this paper we introduce a family of planar, modular and self-similar graphs which have small-world and scale-free properties. The main parameters of this family are comparable to those of networks associated with complex ...
    • Semantic clustering based on ontologies: an application to the study of visitors in a natural reserve 

      Batet, Montserrat; Valls, Aïda; Gibert, Karina (2011)
      Conference report
      Open Access
      The development of large ontologies for general and specific domains provides new tools to improve the quality of data mining techniques such as clustering. In this paper we explain how to improve clustering results by ...
    • Structure and enumeration of K4-minor-free links and link diagrams 

      Rué Perna, Juan José; Thilikos Touloupas, Dimitrios; Velona, Vasiliki (2018-07-01)
      Article
      Open Access
      We study the class L of link-types that admit a K4-minor-free diagram, i.e., they can be projected on the plane so that the resulting graph does not contain any subdivision of K4. We prove that L is the closure of a subclass ...
    • Systematic strategies for 3-dimensional modular robots 

      De Parada Muñoz, Irene María (Universitat Politècnica de Catalunya, 2015-07)
      Master thesis
      Open Access
      Modular robots have been studied an classified from different perspectives, generally focusing on the mechatronics. But the geometric attributes and constraints are the ones that determine the self-reconfiguration strategies. ...