Now showing items 1-20 of 79

    • A new upper bound for 3-SAT 

      Díaz Cort, Josep; Lefteris, Kirousis; Mitsche, Dieter; Perez-Gimenez, Xavier (Schloss Dagstuhl - Leibniz-Zentrum fuer Informatik, Germany, 2008)
      Conference report
      Open Access
      We show that a randomly chosen 3-CNF formula over n variables with clauses-tovariables ratio at least 4.4898 is asymptotically almost surely unsatisfiable. The previous best such bound, due to Dubois in 1999, was 4.506. ...
    • A note on the subgraphs of the (2×\infty)-grid 

      Díaz Cort, Josep; Kaminski, Marcin; Thilikos Touloupas, Dimitrios (2010-02)
      Article
      Restricted access - publisher's policy
      We give a linear-time algorithm checking whether a graph is a subgraph of the (2×k)-grid for some value of k. Our algorithm is based on a detailed characterization of the structure of such graphs.
    • A personal account of Turing’s imprint on the development of computer science 

      Díaz Cort, Josep; Torras, Carme (Elsevier, 2012)
      Article
      Open Access
      The rst part of the XX century saw the development of the digital computer and the eld of computer science. In the present paper, we sketch our vision of that period and of the role that Alan Turing and some of his ...
    • A Random graph model for optical networks of sensors 

      Díaz Cort, Josep; Petit Silvestre, Jordi; Serna Iglesias, María José (2002-12)
      External research report
      Open Access
      In this paper we propose a model for Smart Dust Networks and show its applicability when the goal of the network is monitoring an area under the surveillance of a base station. We analyze basic parameters of these nets and ...
    • A Survey on graph layout problems 

      Díaz Cort, Josep; Petit Silvestre, Jordi; Serna Iglesias, María José (2000-10)
      External research report
      Open Access
      In this paper we survey results on several graph layout problems from an algorithmic point of view. Graph layout problems are a particular class of combinatorial optimization problems whose goal is to find a linear layout ...
    • Absorption time of the Moran process 

      Díaz Cort, Josep; Goldberg, Leslie Ann; Richerby, David; Serna Iglesias, María José (2016-08-01)
      Article
      Open Access
      © 2016 Wiley Periodicals, Inc. The Moran process models the spread of mutations in populations on graphs. We investigate the absorption time of the process, which is the time taken for a mutation introduced at a randomly ...
    • Adversarial models for priority-based networks 

      Álvarez Faura, M. del Carme; Díaz Cort, Josep; Blesa Aguilera, Maria Josep; Fernández Anta, Antonio; Serna Iglesias, María José (2003-06)
      External research report
      Open Access
      We propose several variations of the adversarial queueing model. The priority model takes into account the case in which the packets can have different priorities, assigned by the adversary at injection time. The ...
    • Algorithms for learning finite automata from queries: a unified view 

      Balcázar Navarro, José Luis; Díaz Cort, Josep; Gavaldà Mestre, Ricard; Watanabe, Osamu (1996-09)
      External research report
      Open Access
      In this survey we compare several known variants of the algorithm for learning deterministic finite automata via membership and equivalence queries. We believe that our presentation makes it easier to understand what ...
    • ALGORÍSMICA 

      Díaz Cort, Josep (Universitat Politècnica de Catalunya, 2012-01-18)
      Exam
      Restricted access to the UPC academic community
    • ALGORÍSMICA (Examen 1r quadrim) 

      Díaz Cort, Josep (Universitat Politècnica de Catalunya, 2000-01-29)
      Exam
      Restricted access to the UPC academic community
    • ALGORÍSMICA (Examen 1r quadrim) 

      Díaz Cort, Josep (Universitat Politècnica de Catalunya, 2006-01-12)
      Exam
      Restricted access to the UPC academic community
    • ALGORÍSMICA (Examen 1r quadrim) 

      Díaz Cort, Josep; Pérez, X. (Universitat Politècnica de Catalunya, 2005-01-14)
      Exam
      Restricted access to the UPC academic community
    • ALGORÍSMICA (Examen 1r quadrim) 

      Díaz Cort, Josep (Universitat Politècnica de Catalunya, 2002-01-16)
      Exam
      Restricted access to the UPC academic community
    • ALGORÍSMICA (Examen 1r quadrim) 

      Díaz Cort, Josep (Universitat Politècnica de Catalunya, 2004-01-09)
      Exam
      Restricted access to the UPC academic community
    • ALGORÍSMICA (Examen 1r quadrim) 

      Díaz Cort, Josep (Universitat Politècnica de Catalunya, 2008-01-07)
      Exam
      Restricted access to the UPC academic community
    • ALGORÍSMICA (Examen 1r quadrim) 

      Díaz Cort, Josep (Universitat Politècnica de Catalunya, 2000-06-25)
      Exam
      Restricted access to the UPC academic community
    • ALGORÍSMICA (Examen 1r quadrim) 

      Díaz Cort, Josep (Universitat Politècnica de Catalunya, 1999-01-27)
      Exam
      Restricted access to the UPC academic community
    • Algorítmica per a paral·lelisme massiu : introducció 

      Díaz Cort, Josep; Serna Iglesias, María José (Edicions UPC, 1999)
      Book
      Restricted access to the UPC academic community
      Aquest llibre és una introducció al disseny d’algorismes paral·lels per a màquines síncrones. Als capítols 1-5 es presenten els conceptes bàsics del disseny d’algorismes per a xarxes d’interconexió: vectors, meshes, meshes ...
    • Algunes consideracions teòriques al problema de la construcció d’horaris (comunicació breu) 

      Berenguer, Xavier; Díaz Cort, Josep (Universitat Politècnica de Barcelona. Centre de Càlcul, 1980-03)
      Article
      Open Access
      Corominas i Roselló varen presentar una visió general dels algorismes per a resoldre el problema de la construcció d'horaris en centres escolars. En aquesta comunicació es pretén completar aquest treball amb una revisió ...
    • Approximating layout problems on random sparse graphs 

      Díaz Cort, Josep; Petit Silvestre, Jordi; Serna Iglesias, María José; Trevisan, Marco (1998-07)
      External research report
      Open Access
      We show that, with high probability, several layout problems are approximable within a constant for random graphs drawn from the standard Gnp model with p=c/n for some constant c. Our results establish that, in fact, ...