Now showing items 1-19 of 19

    • A note on the order of iterated line digraphs 

      Dalfó Simó, Cristina; Fiol Mora, Miquel Àngel (Wiley, 2016-07-27)
      Article
      Open Access
      Given a digraph G, we propose a new method to find the recurrence equation for the number of vertices n_k of the k-iterated line digraph L_k(G), for k>= 0, where L_0(G) = G. We obtain this result by using the minimal polynomial ...
    • Algorismes multicast en xarxes overlay 

      Van Creij González, Víctor Alberto (Universitat Politècnica de Catalunya, 2009-10-08)
      Bachelor thesis
      Open Access
    • Application-layer multicast algorithms for bounded delay transmissions 

      Pratsevall Garcia, Jordi (Universitat Politècnica de Catalunya, 2008-12-16)
      Master thesis
      Open Access
      This work shows the design and study of a family of algorithms that solves the multicast routing problem. In this problem, a given node called root has to send information to a certain group of receiving nodes. Although ...
    • Characterizations of classes of graphs by forbidden minors 

      Böhmová, Katerina (Universitat Politècnica de Catalunya, 2011)
      Master thesis
      Open Access
      En aquest treball tractem el problema de descriure classes de grafs especificades per un menor prohibit. Concretament, presentem resultats de Wagner que caracteritzen grafs sense K5 o bé K3,3 com a menor. També donem ...
    • Completion and decomposition of a clutter into representable matroids 

      Martí Farré, Jaume; Mier Vinué, Anna de (Elsevier, 2015-05-01)
      Article
      Open Access
      This paper deals with the question of completing a monotone increasing family of subsets Gamma of a finite set Omega to obtain the linearly dependent subsets of a family of vectors of a vector space. Specifically, we prove ...
    • Computing denumerants in numerical 3-semigroups 

      Aguiló Gost, Francisco de Asis L.; Llena, David (2018)
      Article
      Open Access
      As far as we know, usual computer algebra packages can not compute denumerants for almost medium (about a hundred digits) or almost medium-large (about a thousand digits) input data in a reasonably time cost on an ordinary ...
    • Models gràfics d'independència 

      Duran Rúbies, Josep M. (Institut d'Estadística de Catalunya, 1999)
      Article
      Open Access
      Los modelos gráficos de independencia son una herramienta del análisis multivariante que utiliza gráficos para representar modelos. En particular, los grafos de independencia resumen y clarifican las interacciones entre ...
    • On the spectra of hypertrees 

      Barrière Figueroa, Eulalia; Comellas Padró, Francesc de Paula; Dalfó Simó, Cristina; Fiol Mora, Miquel Àngel (2007-05)
      Article
      Open Access
      In this paper we study the spectral properties of a family of trees characterized by two main features: they are spanning subgraphs of the hypercube, and their vertices bear a high degree of (connectedness) hierarchy. ...
    • Optimization in graphs under degree constraints. application to telecommunication networks 

      Sau Valls, Ignasi (Universitat Politècnica de Catalunya, 2009-10-16)
      Doctoral thesis
      Open Access
      La premi ere partie de cette th ese s'int eresse au groupage de tra c dans les r eseaux de t el ecommunications. La notion de groupage de tra c correspond a l'agr egation de ux de faible d ebit dans des conduits de ...
    • Subgrafos de broadcasting de energía mínima 

      Ozón Górriz, Eduardo (Universitat Politècnica de Catalunya, 2007-06-25)
      Master thesis (pre-Bologna period)
      Open Access
    • Subgrafs d'energia mínima en xarxes ad-hoc 

      Rodríguez Viaplana, Albert; Aymamí Gili, Eva (Universitat Politècnica de Catalunya, 2008-01-23)
      Master thesis (pre-Bologna period)
      Open Access
      En una xarxa de comunicacions ad-hoc els diferents nodes són normalment dispositius sense fils que poden situar-se sobre qualsevol punt de l’espai. En aquest tipus de xarxes s’ha de definir els enllaços entre els ...
    • El teorema dels 4 colors 

      González I Sentís, Marta (Universitat Politècnica de Catalunya, 2017-07)
      Bachelor thesis
      Open Access
      La coloració de grafs és probablement un dels temes més importants de la Teoria de Grafs. En particular existeix un resultat molt significatiu afirmant que tot graf immergible en el pla té una coloració pròpia amb 4 o menys ...
    • The betweenness centrality of a graph 

      Gago Álvarez, Silvia (2007-05-10)
      Article
      Open Access
      A measure of the centrality of a vertex of a graph is the portion of shortest paths crossing through it between other vertices of the graph. This is called betweenness centrality and here we study some of its general ...
    • The Diameter of undirected graphs associated to plane tessellations 

      Andrés Yebra, José Luis; Fiol Mora, Miquel Àngel; Morillo Bosch, M. Paz; Alegre de Miguel, Ignacio (1985)
      Article
      Open Access
      Thi s paper studi es the di ameter of sorne fami I i es of undirected graphs that can be associated to plane tessel lations which fu1 ly represent them. More precisely, we concentrate upon maximizing the order of the ...
    • The Longest path transit function of a graph and betweenness 

      Changat, Manoj; Prasanth, G. N.; Pelayo Melero, Ignacio Manuel (2010)
      Article
      Open Access
    • The spectral excess theorem for distance-regular graphs having distance-d graph with fewer distinct eigenvalues 

      Fiol Mora, Miquel Àngel (2015-01-01)
      Article
      Open Access
      Let G be a distance-regular graph with diameter d and Kneser graph K=Gd, the distance-d graph of G. We say that G is partially antipodal when K has fewer distinct eigenvalues than G. In particular, this is the case of ...
    • Transformation and decomposition of clutters into matroids 

      Martí Farré, Jaume; Mier Vinué, Anna de (2017-05-25)
      Article
      Open Access
      A clutter is a family of mutually incomparable sets. The set of circuits of a matroid, its set of bases, and its set of hyperplanes are examples of clutters arising from matroids. In this paper we address the question of ...
    • Una fórmula explícita para obtener cuadrángulos generalizados y otros grafos pequeños de cintura 8 

      Abreu, M.; Balbuena Martínez, Maria Camino Teófila; Araujo Pardo, M. Gabriela; Labbate, D. (Universidad de Almería, 2011)
      Conference report
      Open Access
      Para cada potencia de primo q, se han constru do (q+1; 8)-jaulas como super cies cu adricas no degeneradas en 4-espacios proyectivos P(4; q). En primer lugar presentamos una construcci on de estos grafos de un modo ...
    • Vertex labeling and routing in expanded Apollonian networks 

      Zhang, Zhongzhi; Comellas Padró, Francesc de Paula; Fertin, Guillaume; Raspaud, André; Rong, Lili; Zhou, Shuigeng (2007-07)
      Article
      Open Access
      We present a family of networks, expanded deterministic Apollonian networks, which are a generalization of the Apollonian networks and are simultaneously scale-free, small-world, and highly clustered. We introduce a ...