Now showing items 1-20 of 106

    • A constraint-based dynamic geometry system 

      Freixas Boleda, Marc; Joan Arinyo, Robert; Soto Riera, Antoni (Elsevier, 2010-02)
      Article
      Restricted access - publisher's policy
      Dynamic geometry systems are tools for geometric visualization. They allow the user to define geometric elements, establish relationships between them and explore the dynamic behavior of the remaining geometric elements ...
    • A kinematic-geometric approach to spatial interpretation of line drawings 

      Ros Giralt, Lluís (Universitat Politècnica de Catalunya, 2000-11-14)
      Doctoral thesis
      Open Access
      This Thesis contributes with new algorithms for line drawing interpretation. A line drawing is a 2D diagram of vertices and straight edges aiming to depict a polyhedral 3D scene. Given one such drawing we usually want ...
    • A methodology to discover and understand complex patterns: interpreted integrative multiview clustering (I2MC) 

      Sevilla-Villanueva, Beatriz; Gibert, Karina; Sànchez-Marrè, Miquel (Elsevier, 2017-02-10)
      Article
      Open Access
      The main goal of this work is to develop a methodology for finding nutritional patterns from a variety of individual characteristics which can contribute to better understand the interactions between nutrition and health, ...
    • A new lower bound on the maximum number of plane graphs using production matrices 

      Huemer, Clemens; Pilz, Alexander; Silveira, Rodrigo Ignacio (2018)
      Conference lecture
      Restricted access - publisher's policy
      We use the concept of production matrices to show that there exist sets of n points in the plane that admit ¿(41.77n) crossing-free geometric graphs. This improves the previously best known bound of ¿(41.18n) by Aichholzer ...
    • A parametric-space-based scan-line algorithm for rendering of bicubic surfaces 

      Pueyo Sánchez, Xavier; Brunet Crosa, Pere (1987)
      Article
      Open Access
      A novel scan-line algorithm for displaying bicubic surfaces is presented. Patches are decomposed on regions of constant sign of the z component of the normal before the scan process. Most of the computations are done in ...
    • Alya: Multiphysics engineering simulation toward exascale 

      Vázquez, Mariano; Houzeaux, Guillaume; Koric, Seid; Artigues, Antoni; Aguado Sierra, Jazmin; Arís Sánchez, Ruth; Mira, Daniel; Calmet, Hadrien; Cucchietti, Fernando; Owen, Herbert; Taha, Ahmed; Dering Burness, Evan; Cela Espín, José M.; Valero Cortés, Mateo (Elsevier, 2016-05)
      Article
      Open Access
      Alya is a multi-physics simulation code developed at Barcelona Supercomputing Center (BSC). From its inception Alya code is designed using advanced High Performance Computing programming techniques to solve coupled problems ...
    • An octree isosurface codification based on discrete planes 

      Boada, Imma; Navazo Álvaro, Isabel (2001)
      Conference report
      Open Access
      Describes a method to code a decimated model of an isosurface on an octree representation while maintaining volume data if it is needed. The proposed technique is based on grouping the marching cubes (MC) patterns into ...
    • Analysis and Prediction of Human Motion Trajectories in Urban Environments 

      Ferrer M´ınguez, Gonzalo (Universitat Politècnica de Catalunya, 2011-09)
      Master thesis
      Restricted access - author's decision
      The design and development of intelligent service mobile robots that interact with humans in daily living activities or cooperate with persons in specific tasks, requires the design of new tools that allow the understanding ...
    • Blocking the k-holes of point sets in the plane 

      Cano, Javier; Garcia Olaverri, Alfredo Martin; Hurtado Díaz, Fernando Alfredo; Shakai, Toshinori; Tejel Altarriba, Francisco Javier; Urrutia Galicia, Jorge (2015-09)
      Article
      Open Access
      Let P be a set of n points in the plane in general position. A subset H of P consisting of k elements that are the vertices of a convex polygon is called a k-hole of P, if there is no element of P in the interior of its ...
    • Bounds on the coefficients of tension and flow polynomials 

      Breuer, Felix; Dall, Aaron Matthew (2011-05)
      Article
      Restricted access - publisher's policy
      The goal of this article is to obtain bounds on the coefficients of modular and integral flow and tension polynomials of graphs. To this end we use the fact that these polynomials can be realized as Ehrhart polynomials of ...
    • Caminos de desviación mínima local 

      Abellanas, Manuel; Hernández, Gregorio; Sacristán Adinolfi, Vera (U. Zaragoza, 2009)
      Conference report
      Open Access
      Un camino que conecta dos puntos s y t en el plano es de desviación mínima respecto de un conjunto de puntos S si la mayor de las distancias entre un punto del camino y S es la menor posible entre todos los caminos que ...
    • Cell-paths in mono- and bichromatic line arrangements in the plane 

      Aichholzer, Oswin; Cardinal, Jean; Hackl, Thomas; Hurtado Díaz, Fernando Alfredo; Korman Cozzetti, Matías; Pilz, Alexander; Silveira, Rodrigo Ignacio; Uehara, Ryuhei; Vogtenhuber, Birgit; Welzl, Emo (2014)
      Conference report
      Open Access
      We show that in every arrangement of n red and blue lines | in general position and not all of the same color | there is a path through a linear number of cells where red and blue lines are crossed alternatingly (and no ...
    • Colored Ray configurations 

      Fabila Monroy, Ruy; Garcia Olaverri, Alfredo Martin; Hurtado Díaz, Fernando Alfredo; Jaume, Rafel; Pérez Lantero, Pablo; Saumell, Maria; Silveira, Rodrigo Ignacio; Tejel Altarriba, Francisco Javier; Urrutia Galicia, Jorge (2014)
      Conference report
      Open Access
      We study the cyclic sequences induced at in nity by pairwise-disjoint colored rays with apices on a given bal- anced bichromatic point set, where the color of a ray is inherited from the color of its apex. We derive a lower ...
    • Combining geometric and appearance priors for pose recovery 

      Seradel Domingo, Eduard (Universitat Politècnica de Catalunya, 2009-09)
      Master thesis
      Restricted access - author's decision
      Estimar la pose (rotació i translació) de la càmera a partir dels punts d'interés de l'escena 3D i punts de la imatge 2D és un problema ben resolt en el cas que es coneguin les correspondències entre ells. No obstant, quan ...
    • Complejidad de estructuras geométricas y combinatorias 

      Hernando Martín, M. Carmen (Universitat Politècnica de Catalunya, 1999-04-30)
      Doctoral thesis
      Open Access
      En la presente memoria, se abordan cuatro problemas, existiendo en todos ellos una gran interacción entre la combinatoria y la geometría. El primer problema que se estudia es la introducción de varias extensiones del ...
    • Computing a visibility polygon using few variables 

      Barba, Luis; Korman Cozzetti, Matías; Langerman, Stefan; Silveira, Rodrigo Ignacio (2014-10-01)
      Article
      Restricted access - publisher's policy
      We present several algorithms for computing the visibility polygon of a simple polygon P of n vertices (out of which r are reflex) from a viewpoint inside P, when P resides in read-only memory and only few working variables ...
    • Computing correlation between piecewise-linear functions 

      Agarwal, Pankaj; Aronov, Boris; Van Kreveld, Matias; Löffler, Maarten; Silveira, Rodrigo Ignacio (2013)
      Article
      Restricted access - publisher's policy
      We study the problem of computing correlation between two piecewise-linear bivariate functions defined over a common domain, where the surfaces they define in three dimensions---polyhedral terrains---can be transformed ...
    • Computing maximal tiles and application to impostor-based simplification 

      Andújar Gran, Carlos Antonio; Brunet Crosa, Pere; Chica Calaf, Antonio; Navazo Álvaro, Isabel; Rossignac, Jarek; Vinacua Pla, Álvaro (North Holland, 2004-08)
      Article
      Restricted access - publisher's policy
      The computation of the largest planar region approximating a 3D object is an important problem with wide applications in modeling and rendering. Given a voxelization of the 3D object, we propose an efficient algorithm to ...
    • Configurations of non-crossing rays and related problems 

      Garcia Olaverri, Alfredo Martin; Hurtado Díaz, Fernando Alfredo; Tejel Altarriba, Francisco Javier; Urrutia Galicia, Jorge (2016-04)
      Article
      Open Access
      Let S be a set of n points in the plane and let R be a set of n pairwise non-crossing rays, each with an apex at a different point of S. Two sets of non-crossing rays R1R1 and R2R2 are considered to be different if the ...
    • Connecting Red Cells in a Bicolour Voronoi Diagram 

      Abellanas, Manuel; Bajuelos, Antonio L.; Canales, Santiago; Claverol Aguas, Mercè; Hernández, Gregorio; Pereira de Matos, Inés (2012-11)
      Article
      Restricted access - publisher's policy
      Let S be a set of n + m sites, of which n are red and have weight wR, and m are blue and weigh wB. The objective of this paper is to calculate the minimum value of the red sites’ weight such that the union of the red ...