Now showing items 1-4 of 4

    • A sufficient degree condition for a graph to contain all trees of size k 

      Balbuena Martínez, Maria Camino Teófila; Márquez, Alberto; Portillo, Jose Ramón (Springer Verlag, 2011-01)
      Restricted access - publisher's policy
      The Erdős-Sós conjecture says that a graph G on n vertices and number of edges e(G) > n(k− 1)/2 contains all trees of size k. In this paper we prove a sufficient condition for a graph to contain every tree of size k ...

      Márquez, Alberto (Universitat Politècnica de Catalunya, 2007-10-31)
      Restricted access to the UPC academic community
    • Stabbers of line segments in the plane 

      Claverol Aguas, Mercè; Garijo, Delia; Grima, Clara; Márquez, Alberto; Seara Ojea, Carlos (2011-07)
      Open Access
      The problem of computing a representation of the stabbing lines of a set S of segments in the plane was solved by Edelsbrunner et al. We provide efficient algorithms for the following problems: computing the stabbing wedges ...
    • Witness bar visibility graphs 

      Cortés, Carmen; Hurtado Díaz, Fernando Alfredo; Márquez, Alberto; Valenzuela, Jesús (2013)
      Conference report
      Open Access
      Bar visibility graphs were introduced in the seventies as a model for some VLSI layout problems. They have been also studied since then by the graph drawing community, and recently several generalizations and restricted ...