Now showing items 1-8 of 8

    • Diseño e implementación de algoritmos de unificación y matching para términos comprimidos. 

      Ramos Garrido, Lander (Universitat Politècnica de Catalunya, 2011-06-30)
      Master thesis (pre-Bologna period)
      Open Access
      Las gramáticas incontextuales se pueden utilizar como herramienta para comprimir palabras o términos. Estas gramáticas pueden permitir en casos extremos comprimir hasta un factor exponencial. Sobre este tipo de compresiones ...
    • Excessively duplicating patterns represent non-regular languages 

      Creus López, Carles; Godoy Balil, Guillem; Ramos Garrido, Lander (2014-03-01)
      Article
      Restricted access - publisher's policy
      A constrained term pattern s:¿ represents the language of all instances of the term s satisfying the constraint ¿. For each variable in s, this constraint specifies the language of its allowed substitutions. Regularity of ...
    • Graph enumeration and random graphs 

      Ramos Garrido, Lander (Universitat Politècnica de Catalunya, 2017-03-27)
      Doctoral thesis
      Open Access
      In this thesis we use analytic combinatorics to deal with two related problems: graph enumeration and random graphs from constrained classes of graphs. We are interested in drawing a general picture of some graph families ...
    • Maximal independent sets and maximal matchings in series-parallel and related graph classes 

      Drmota, Michael; Ramos Garrido, Lander; Requilé, Clément; Rué Perna, Juan José (2020-01-10)
      Article
      Open Access
      The goal of this paper is to obtain quantitative results on the number and on the size of maximal independent sets and maximal matchings in several block-stable graph classes that satisfy a proper sub-criticality condition. ...
    • Subgraph statistics in subcritical graph classes 

      Drmota, Michael; Ramos Garrido, Lander; Rué Perna, Juan José (2017-04-01)
      Article
      Open Access
      Let H be a fixed graph and math formula a subcritical graph class. In this paper we show that the number of occurrences of H (as a subgraph) in a graph in math formula of order n, chosen uniformly at random, follows a ...
    • The HOM problem is decidable 

      Godoy, Guillem; Giménez, Omer; Ramos Garrido, Lander; Álvarez Faura, M. del Carme (2009-06)
      External research report
      Open Access
      We close affirmatively a question which has been open for 35 years: decidability of the HOM problem. The HOM problem consists in deciding, given a tree homomorphism $H$ and a regular tree languagle $L$ represented by a ...
    • The HOM problem is EXPTIME-complete 

      Creus López, Carles; Gascon Caro, Adrian; Godoy Balil, Guillem; Ramos Garrido, Lander (2016)
      Article
      Open Access
      We define a new class of tree automata with constraints and prove decidability of the emptiness problem for this class in exponential time. As a consequence, we obtain several EXPTIME-completeness results for problems on ...
    • Too much duplicating patterns represent nonregular languages 

      Ramos Garrido, Lander (Universitat Politècnica de Catalunya, 2011)
      Master thesis
      Open Access
      A constrained term pattern s:phi represents the language of all instances of the term s satisfying the constraint phi. For each variable in s, this constraint specifies the language of its allowed substitutions. The ...