• Búsqueda de comunidades en grafos grandes mediante configuraciones implícitas de vectores 

    Muntés Mulero, Víctor; Padrol Sureda, Arnau; Perarnau Llobet, Guillem; Pfeifle, Julián (PUBL. UNIVERSIDAD DE ZARAGOZA, 2009)
    Text en actes de congrés
    Accés obert
    Presentamos el algoritmo OCA para buscar comunidades solapadas en grafos grandes, como por ejemplo la Wikipedia con 1,6×107 nodos y 1,8×108 aristas. OCA se basa en la búsqueda iterativa de subconjuntos localmente óptimos ...
  • Constructing neighborly polytopes and oriented matroids 

    Padrol Sureda, Arnau (2012)
    Comunicació de congrés
    Accés obert
    A d-polytope P is neighborly if every subset of b d 2 c vertices is a face of P. In 1982, Shemer introduced a sewing construction that allows to add a vertex to a neighborly polytope in such a way as to obtain a new ...
  • Graph operations and Laplacian eigenpolytopes 

    Padrol Sureda, Arnau; Pfeifle, Julián (2010-07)
    Text en actes de congrés
    Accés obert
    We introduce the Laplacian eigenpolytopes ("L-polytopes") associated to a simple undirected graph G, investigate how they change under basic operations such as taking the union, join, complement, line graph and cartesian ...
  • Neighborly and almost neighborly configurations, and their duals 

    Padrol Sureda, Arnau (Universitat Politècnica de Catalunya, 2013-03-12)
    Tesi
    Accés obert
    This thesis presents new applications of Gale duality to the study of polytopes with extremal combinatorial properties. It consists in two parts. The first one is devoted to the construction of neighborly polytopes and ...
  • Overlapping community search for social networks 

    Padrol Sureda, Arnau; Perarnau Llobet, Guillem; Pfeifle, Julián; Muntés Mulero, Víctor (IEEE Press. Institute of Electrical and Electronics Engineers, 2010)
    Text en actes de congrés
    Accés obert
    Finding decompositions of a graph into a family of clusters is crucial to understanding its underlying structure. While most existing approaches focus on partitioning the nodes, real-world datasets suggest the presence ...
  • Overlapping community search in very large graphs 

    Padrol Sureda, Arnau (Universitat Politècnica de Catalunya, 2009-06)
    Projecte Final de Màster Oficial
    Accés obert
    "In this master thesis we present a novel approach to finding communities in large graphs. Our method finds the overlapped and hierarchical structure of communities efficiently, outperforming previous proposals. We propose ...
  • Overlapping community search in very large graphs 

    Padrol Sureda, Arnau (Universitat Politècnica de Catalunya, 2010-01)
    Projecte Final de Màster Oficial
    Accés obert
    The main objective of the thesis is the creation of an algorithm to detect the community structure of large graphs, allowing for nestings and overlappings. Although it has been shown that communities are usually ...
  • Polygons as sections of higher-dimensional polytopes 

    Padrol Sureda, Arnau; Pfeifle, Julián (2015-02-09)
    Article
    Accés obert
    We show that every heptagon is a section of a 3-polytope with 6 vertices. This implies that every n-gon with n >= 7 can be obtained as a section of a (2 + [n/7])-dimensional polytope with at most [6n/7] vertices; and ...