Browsing by Author "Silveira, Rodrigo Ignacio"
Now showing items 120 of 61

A faster algorithm to compute the visibility map of a 1.5D terrain
Löffler, Maarten; Saumell, Maria; Silveira, Rodrigo Ignacio (2014)
Conference report
Open AccessGiven a 1.5D terrain, i.e., an x monotone polygonal line in R 2 with n vertices, and 1 m n viewpoints placed on some of the terrain vertices, we study the problem of computing the parts of the terrain that are visible ... 
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 policyWe use the concept of production matrices to show that there exist sets of n points in the plane that admit ¿(41.77n) crossingfree geometric graphs. This improves the previously best known bound of ¿(41.18n) by Aichholzer ... 
A new lower bound on the maximum number of plane graphs using production matrices
Huemer, Clemens; Pilz, Alexander; Silveira, Rodrigo Ignacio (20191101)
Article
Open AccessWe use the concept of production matrices to show that there exist sets of n points in the plane that admit ¿(42.11n ) crossingfree geometric graphs. This improves the previously best known bound of ¿(41.18n ) by Aichholzer ... 
A new metamodule for efficient reconfiguration of hingedunits modular robots
Parada, Irene; Sacristán Adinolfi, Vera; Silveira, Rodrigo Ignacio (Institute of Electrical and Electronics Engineers (IEEE), 2016)
Conference report
Open AccessWe present a robust and compact metamodule for edgehinged modular robot units such as MTRAN, SuperBot, SMORES, UBot, PolyBot and CKBot, as well as for centralpointhinged ones such as Molecubes and Roombots. Thanks ... 
A note on flips in diagonal rectangulations
Cardinal, Jean; Sacristán Adinolfi, Vera; Silveira, Rodrigo Ignacio (Chapman & Hall/CRC, 20181109)
Article
Open AccessRectangulations are partitions of a square into axisaligned rectangles. A number of results provide bijections between combinatorial equivalence classes of rectangulations and families of patternavoiding permutations. ... 
A scalable method to construct compact road networks from GPS trajectories
Guo, Yuejun; Bardera Reig, Anton; Fort Masdevall, Marta; Silveira, Rodrigo Ignacio (20201006)
Article
Restricted access  publisher's policyThe automatic generation of road networks from GPS tracks is a challenging problem that has been receiving considerable attention in the last years. Although dozens of methods have been proposed, current techniques suffer ... 
Adjacencypreserving spatial treemaps
Buchin, Kevin; Eppstein, David; Löffler, Maarten; Nöllenburg, Martin; Silveira, Rodrigo Ignacio (2016)
Article
Open AccessRectangular layouts, subdivisions of an outer rectangle into smaller rectangles, have many applications in visualizing spatial information, for instance in rectangular cartograms in which the rectangles represent geographic ... 
Affine invariant triangulations
Bose, Prosenjit; Cano Vila, María del Pilar; Silveira, Rodrigo Ignacio (2019)
Conference report
Restricted access  publisher's policyWe study affine invariant 2D triangulation methods. That is, methods that produce the same triangulation for a point set S for any (unknown) affine transformation of S. Our work is based on a method by Nielson [A ... 
Balanced partitions of 3colored geometric sets in the plane
Bereg, Sergey; Hurtado Díaz, Fernando Alfredo; Kano, Mikio; Korman, Matias; Lara, Dolores; Seara Ojea, Carlos; Silveira, Rodrigo Ignacio; Urrutia Galicia, Jorge; Verbeek, Kevin (2015)
Article
Open AccessLet SS be a finite set of geometric objects partitioned into classes or colors . A subset S'¿SS'¿S is said to be balanced if S'S' contains the same amount of elements of SS from each of the colors. We study several ... 
Cellpaths 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 AccessWe 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 ... 
Characteristic polynomials of production matrices for geometric graphs
Huemer, Clemens; Pilz, Alexander; Seara Ojea, Carlos; Silveira, Rodrigo Ignacio (20170801)
Article
Open AccessAn n×n production matrix for a class of geometric graphs has the property that the numbers of these geometric graphs on up to n vertices can be read off from the powers of the matrix. Recently, we obtained such production ... 
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 AccessWe study the cyclic sequences induced at in nity by pairwisedisjoint 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 ... 
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 (201805)
Article
Open AccessWe study the cyclic color sequences induced at infinity by colored rays with apices being a given balanced finite bichromatic point set. We first study the case in which the rays are required to be pairwise disjoint. We ... 
Colored spanning graphs for set visualization
Hurtado Díaz, Fernando Alfredo; Korman, Matias; Van Kreveld, Matias; Löffler, Maarten; Sacristán Adinolfi, Vera; Shioura, Akiyoshi; Silveira, Rodrigo Ignacio; Speckmann, Bettina; Tokuyama, Takeshi (201803)
Article
Open AccessWe study an algorithmic problem that is motivated by ink minimization for sparse set visualizations. Our input is a set of points in the plane which are either blue, red, or purple. Blue points belong exclusively to the ... 
Colored spanning graphs for set visualization
Hurtado Díaz, Fernando Alfredo; Korman Cozzetti, Matías; Van Kreveld, Matias; Löffler, Maarten; Sacristán Adinolfi, Vera; Silveira, Rodrigo Ignacio; Speckmann, Bettina (Springer, 2013)
Conference report
Open AccessWe study an algorithmic problem that is motivated by ink minimization for sparse set visualizations. Our input is a set of points in the plane which are either blue, red, or purple. Blue points belong exclusively to the ... 
Computing a visibility polygon using few variables
Barba, Luis; Korman Cozzetti, Matías; Langerman, Stefan; Silveira, Rodrigo Ignacio (20141001)
Article
Restricted access  publisher's policyWe 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 readonly memory and only few working variables ... 
Computing correlation between piecewiselinear functions
Agarwal, Pankaj; Aronov, Boris; Van Kreveld, Matias; Löffler, Maarten; Silveira, Rodrigo Ignacio (2013)
Article
Restricted access  publisher's policyWe study the problem of computing correlation between two piecewiselinear bivariate functions defined over a common domain, where the surfaces they define in three dimensionspolyhedral terrainscan be transformed ... 
Computing optimal shortcuts for networks
Garijo Royo, Delia; Marquez Pérez, Alberto; Rodríguez, Natalia; Silveira, Rodrigo Ignacio (2018)
Conference report
Open AccessWe augment a plane Euclidean network with a segment or shortcut to minimize the largest distance between any two points along the edges of the resulting network. In this continuous setting, the problem of computing distances ... 
Computing optimal shortcuts for networks
Garijo Royo, Delia; Marquez Pérez, Alberto; Rodríguez, Natalia; Silveira, Rodrigo Ignacio (2018)
Conference report
Open AccessWe study augmenting a plane Euclidean network with a segment, called shortcut, to minimize the largest distance between any two points along the edges of the resulting network. Questions of this type have received considerable ... 
Computing optimal shortcuts for networks
Garijo Royo, Delia; Marquez Pérez, Alberto; Rodríguez, Natalia; Silveira, Rodrigo Ignacio (Elsevier, 20191116)
Article
Restricted access  publisher's policyWe study augmenting a plane Euclidean network with a segment, called a shortcut, to minimize the largest distance between any two points along the edges of the resulting network. Problems of this type have received ...