Mostrando ítems 1-20 de 35

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      Flips in combinatorial pointed pseudo-triangulations with face degree at most four 

      Aichholzer, Oswin; Hackl, Thomas; Orden Martín, David; Pilz, Alexander; Saumell Mendiola, María; Vogtenhuber, Birgit (2013)
      In this paper we consider the flip operation for combinatorial pointed pseudo-triangulations where faces have size 3 or ...
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      Monotone crossing number of complete graphs 

      Balko, Martin; Fulek, Radoslav; Kynčl, Jan (2013)
      In 1958, Hill conjectured that the minimum number of crossings in a drawing of Kn is exactly Z(n) = 1/4 n-1/2/2 n−2/2 ...
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      On 4-connected geometric graphs 

      García Olaverri, Alfredo; Huemer, Clemens; Tejel Altarriba, Francisco Javier; Valtr, Pavel (2013)
      Given a set S of n points in the plane, in this paper we give a necessary and sometimes sufficient condition to build a 4-connected non-crossing geometric graph on S.
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      Phase transitions in the Ramsey-Turán theory 

      Balogh, József (2013)
      Let f(n) be a function and L be a graph. Denote by RT(n, L, f(n)) the maximum number of edges of an L-free graph on n ...
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      The alternating path problem revisited 

      Claverol Aguas, Mercè; Garijo Royo, Delia; Hurtado Díaz, Ferran; Lara Cuevas, María Dolores; Seara Ojea, Carlos (2013)
      It is well known that, given n red points and n blue points on a circle, it is not always possible to find a plane geometric ...
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      Witness bar visibility 

      Cortés Parejo, María del Carmen; Hurtado Díaz, Ferran; Márquez Pérez, Alberto; Valenzuela Muñoz, Jesús (2013)
      Bar visibility graphs were introduced in the seventies as a model for some VLSI layout problems. They have been also studied ...
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      On making a graph crossing-critical 

      Hernández Vélez, César Israel; Leaños Macías, Jesús (2013)
      A graph is crossing-critical if its crossing number decreases when we remove any of its edges. Recently it was proved that ...
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      On three parameters of invisibility graphs 

      Cibulka, Josef; Korbelář, Miroslav; Kynčl, Jan; Mészáros, Viola; Stolař, Rudolf; Valtr, Pavel (2013)
      The invisibility graph I(X) of a set X ⊆ Rd is a (possibly infinite) graph whose vertices are the points of X and two ...
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      Improved enumeration of simple topological graphs 

      Kynčl, Jan (2013)
      A simple topological graph T = (V (T ), E(T )) is a drawing of a graph in the plane where every two edges have at most one ...
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      Stackable tessellations 

      Enrique Monzo, Lluís; Jaume Deyà, Rafel (2013)
      We introduce a class of solids that can be constructed gluing stackable pieces, which has been proven to have advantages ...
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      Stabbing simplices of point sets with k-flats 

      Cano Vila, Javier; Hurtado Díaz, Ferran; Urrutia Galicia, Jorge (2013)
      Let S be a set of n points in Rd in general position. A set H of k-flats is called an mk-stabber of S if the relative ...
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      Note on the number of obtuse angles in point sets 

      Fabila Monroy, Ruy; Huemer, Clemens; Tramuns Figueras, Eulàlia (2013)
      In 1979 Conway, Croft, Erd\H{o}s and Guy proved that every set SS of nn points in general position in the plane determines ...
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      Empty convex polytopes in random point sets 

      Balogh, József; González Aguilar, Hernán; Salazar Anaya, Gelasio (2013)
      Given a set P of points in Rd, a convex hole (alternatively, empty convex polytope) of P is a convex polytope with vertices ...
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      Simulating distributed algorithms for lattice agents 

      Aichholzer, Oswin; Hackl, Thomas; Sacristán Adinolfi, Vera; Vogtenhuber, Birgit; Wallner, Reinhardt (2013)
      We present a practical Java tool for simulating synchronized distributed algorithms on sets of 2-and 3-dimensional ...
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      A symbolic-numeric dynamic geometry environment for the computation of equidistant curves 

      Abánades Astudillo, Miguel Ángel; Botana Ferreiro, Francisco (2013)
      A web-based system that determines point/curve and curve/curve bisectors in a dynamic geometry system in a completely ...
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      Simulated annealing applied to the MWPT problem 

      Gagliardi, Edilma Olinda; Leguizamón, Mario Guillermo; Hernández Peñalver, Gregorio (2013)
      The Minimum Weight Pseudo-Triangulation (MWPT) problem is suspected to be NP-hard. We show here how Simulated Annealing ...
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      SensoGraph: Using proximity graphs for sensory analysis 

      Miguel, David N. de; Orden Martín, David; Fernández Fernández, Encarnación; Rodríguez Nogales, José Manuel; Vila Crespo, Josefina (2013)
      Sensory evaluation of foods is as important as chemical, physical or microbiological examinations, being specially relevant ...
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      Drawing the double circle on a grid of minimum size 

      Bereg, Sergey; Fabila Monroy, Ruy; Flores Peñaloza, David; Lopez, Mario A.; Pérez Lantero, Pablo (2013)
      In 1926, Jarník introduced the problem of drawing a convex n-gon with vertices having integer coordinates. He constructed ...
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      On the nonexistence of k-reptile simplices in R3 and R4 

      Kynčl, Jan; Safernova, Zuzana (2013)
      A d-dimensional simplex S is called a k-reptile (or a k-reptile simplex) if it can be tiled without overlaps by k simplices ...