Now showing items 1-20 of 121

    • A branch-and-price algorithm for the Aperiodic Multi-Period Service Scheduling Problem 

      Fernández Aréizaga, Elena; Kalcsics, Jörg; Núñez del Toro, Alma Cristina (Elsevier, 2017-12-16)
      Article
      Open Access
      This paper considers the multi-period service scheduling problem with an aperiodic service policy. In this problem, a set of customers who periodically require service over a finite time horizon is given. To satisfy the ...
    • A combinatorial method for the evaluation of yield of fault-tolerant systems-on-chip 

      Suñé, Víctor; Rodríguez Montañés, Rosa; Carrasco, Juan A.; Munteanu, D-P (2003)
      Conference report
      Open Access
      In this paper we develop a combinatorial method for the evaluation of yield of fault-tolerant systems-on-chip. The method assumes that defects are produced according to a model in which defects are lethal and affect given ...
    • A connection between Inverse Problems and Nonstandard Analysis 

      Martínez Moraian, Alejandra (Universitat Politècnica de Catalunya, 2018-10)
      Master thesis
      Restricted access - author's decision
      Nonstandard analysis was born in the decade of 1960 an attempt to give a formal context to the Leibniz approach to differential calculus, in particular in order to provide a rigorous foundation to the notions of infinitesimal ...
    • A finite version of the Kakeya problem 

      Ball, Simeon Michael; Blokhuis, Aart; Domenzain, Diego (2016-06-02)
      Article
      Open Access
      Let L be a set of lines of an affine space over a field and let S be a set of points with the property that every line of L is incident with at least N points of S. Let D be the set of directions of the lines of L considered ...
    • A novel model for arc territory design: promoting Eulerian districts 

      Garcia Ayala, Gariela; González Velarde, José Luis; Rios Mercados, Roger; Fernández Aréizaga, Elena (2015-01-01)
      Article
      Open Access
      The problem of district design for the implementation of arc routing activities is addressed. The aim is to partition a road network into a given number of sectors to facilitate the organization of the operations to be ...
    • A Random Features Model for Contextual Multi-armed Bandits with Non-linear Reward Function 

      Bernal Sagué, Sergi (Universitat Politècnica de Catalunya, 2020-06)
      Bachelor thesis
      24 months embargo
    • 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)
      Article
      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 ...
    • Activities and coefficients of the Tutte polynomial 

      Hakim, Sahar (Universitat Politècnica de Catalunya, 2019-01)
      Master thesis
      Open Access
      Matroids are combinatorial objects that capture abstractly the essence of dependence. The Tutte polynomial, defined for matroids and graphs, has a numerous amount of information about these structures. In this thesis, we ...
    • Algebraic characterizations of bipartite distance-regular graphs 

      Fiol Mora, Miquel Àngel (Iniciativa Digital Politècnica, 2011)
      Conference report
      Open Access
      Bipartite graphs are combinatorial objects bearing some interesting symmetries. Thus, their spectra—eigenvalues of its adjacency matrix—are symmetric about zero, as the corresponding eigenvectors come into pairs. Moreover, ...
    • Algorithms for the weighted independent domination problem 

      Rodríguez Corominas, Guillem (Universitat Politècnica de Catalunya, 2019-07-04)
      Bachelor thesis
      Open Access
      El problema de la dominació independent ponderada és un problema NP-hard d'optimització combinatòria en grafs. Aquest problema només ha estat abordat a la literatura per enfocaments de programació lineal entera, heurístiques ...
    • An algebraic fractal approach to Collatz Conjecture 

      Martín Chabrera, Víctor (Universitat Politècnica de Catalunya, 2019-05)
      Bachelor thesis
      Open Access
      The Collatz conjecture is one of the most easy-to-state unsolved problems in Mathematics today. It states that after a finite number of iterations of the Collatz function, defined by C(n) = n/2 if n is even, and by C(n) = ...
    • An algebraic framework for Diffie-Hellman assumptions 

      Escala Ribas, Alex; Herold, Gottfried; Kiltz, Eike; Ràfols Salvador, Carla; Villar Santos, Jorge Luis (2017-01)
      Article
      Open Access
      We put forward a new algebraic framework to generalize and analyze Di e-Hellman like Decisional Assumptions which allows us to argue about security and applications by considering only algebraic properties. Our D`;k-MDDH ...
    • An analogue of Vosper's theorem for extension fields 

      Bachoc, Christine; Serra Albó, Oriol; Zemor, Gilles (2017-11-01)
      Article
      Open Access
      We are interested in characterising pairs S, T of F-linear subspaces in a field extension L/F such that the linear span ST of the set of products of elements of S and of elements of T has small dimension. Our central result ...
    • An ROBDD-based combinatorial method for the evaluation of yield of defect-tolerant systems-on-chip 

      Carrasco, Juan A.; Suñé, Víctor (2009-02)
      Article
      Open Access
      In this paper, we develop a combinatorial method for the evaluation of the functional yield of defect-tolerant systems-on chip (SoC). The method assumes that random manufacturing defects are produced according to a model ...
    • Analytic combinatorics of chord and hyperchord diagrams with k crossings 

      Pilaud, Vincent; Rué Perna, Juan José (2014-05-07)
      Article
      Open Access
      Using methods from Analytic Combinatorics, we study the families of perfect matchings, partitions, chord diagrams, and hyperchord diagrams on a disk with a prescribed number of crossings. For each family, we express the ...
    • Approximation schemes for randomly sampling colorings 

      González I Sentís, Marta (Universitat Politècnica de Catalunya, 2019-10)
      Master thesis
      Open Access
      Graph colouring is arguably one of the most important issues in Graph Theory. However, many of the questions that arise in the area such as the chromatic number problem or counting the number of proper colorings of a graph ...
    • Arcs and tensors 

      Ball, Simeon Michael; Lavrauw, Michel (2019-08-01)
      Article
      Open Access
      To an arc A of PG(k-1,q) of size q+k-1-t we associate a tensor in ¿¿k,t(A)¿¿k-1 , where ¿k,t denotes the Veronese map of degree t defined on PG(k-1,q) . As a corollary we prove that for each arc A in PG(k-1,q) of size ...
    • Bijections for Baxter families and related objects 

      Felsner, Stefan; Fusy, Éric; Noy Serrano, Marcos; Orden, David (2011-04)
      Article
      Open Access
      The Baxter number can be written as $B_n = \sum_0^n \Theta_{k,n-k-1}$. These numbers have first appeared in the enumeration of so-called Baxter permutations; $B_n$ is the number of Baxter permutations of size $n$, and ...
    • Binary labelings for plane quadrangulations and their relatives 

      Felsner, Stefan; Huemer, Clemens; Kappes, Sarah; Orden, David (2010)
      Article
      Open Access
      Motivated by the bijection between Schnyder labelings of a plane triangulation and partitions of its inner edges into three trees, we look for binary labelings for quadrangulations (whose edges can be partitioned into two ...
    • c-Critical graphs with maximum degree three 

      Fiol Mora, Miquel Àngel (John Wiley and Sons, Inc., 1995)
      Part of book or chapter of book
      Restricted access - publisher's policy
      Let $G$ be a (simple) gtoph with maximum degree three and chromatic index four. A 3-edge-coloring of G is a coloring of its edges in which only three colors are used. Then a vertex is conflicting when some edges incident ...