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Mostrando ítems 31-40 de 43
Ponencia
A symbolic-numeric dynamic geometry environment for the computation of equidistant curves
(2013)
A web-based system that determines point/curve and curve/curve bisectors in a dynamic geometry system in a completely automatic way is presented. The system consists of an interactive drawing canvas where the bisector is ...
Ponencia
On the nonexistence of k-reptile simplices in R3 and R4
(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 with disjoint interiors that are all mutually congruent and similar to S. For d=2, triangular ...
Ponencia
Drawing the double circle on a grid of minimum size
(2013)
In 1926, Jarník introduced the problem of drawing a convex n-gon with vertices having integer coordinates. He constructed such a drawing in the grid [1, c ·n 3/2]2 for some constant c > 0, and showed that this grid size ...
Ponencia
Note on the number of obtuse angles in point sets
(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 at least n3/18−O(n2) obtuse angles and also presented a special set of nn points to show the upper ...
Ponencia
Guarding the vertices of thin orthogonal polygons is NP-hard
(2013)
An orthogonal polygon of P is called “thin” if the dual graph of the partition obtained by extending all edges of P towards its interior until they hit the boundary is a tree. We show that the problem of computing a minimum ...
Ponencia
Distance domination, guarding and vertex cover for maximal outerplanar graphs
(2013)
In this paper we de ne a distance guarding concept on plane graphs and associate this concept with distance domination and distance vertex cover concepts on triangulation graphs. Furthermore, for any n-vertex maximal ...
Ponencia
Flips in combinatorial pointed pseudo-triangulations with face degree at most four
(2013)
In this paper we consider the flip operation for combinatorial pointed pseudo-triangulations where faces have size 3 or 4, so-called combinatorial 4-PPTs. We show that every combinatorial 4-PPT is stretchable to a geometric ...
Ponencia
On three parameters of invisibility graphs
(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 vertices are connected by an edge if and only if the straight-line segment connecting the two corresponding ...
Ponencia
Empty convex polytopes in random point sets
(2013)
Given a set P of points in Rd, a convex hole (alternatively, empty convex polytope) of P is a convex polytope with vertices in P, containing no points of P in its interior. Let R be a bounded convex region in Rd. We show ...
Capítulo de Libro
Diferenciales cuadráticas holomorfas en superficies lineales de Weingarten elípticas
(Godel, 2015)
En este trabajo definimos una diferencial de Hopf para superficies lineales de Weingarten que además satisfacen una relación de tipo elíptico al ser vistas como grafo sobre sus planos tangentes. Como consecuencia damos ...