### Recent Submissions

• Presentation #### Recent developments on the crossing number of the complete graph ﻿

(2013)
• Presentation #### 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 ...
• Presentation #### Monotone crossing number of complete graphs ﻿

(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 ...
• Presentation #### On 4-connected geometric graphs ﻿

(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.
• Presentation #### Phase transitions in the Ramsey-Turán theory ﻿

(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 ...
• Presentation #### The alternating path problem revisited ﻿

(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 ...
• Presentation #### Witness bar visibility ﻿

(2013)
Bar visibility graphs were introduced in the seventies as a model for some VLSI layout problems. They have been also studied ...
• Presentation #### On making a graph crossing-critical ﻿

(2013)
A graph is crossing-critical if its crossing number decreases when we remove any of its edges. Recently it was proved that ...
• Presentation #### 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 ...
• Presentation #### Improved enumeration of simple topological graphs ﻿

(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 ...
• Presentation #### Stackable tessellations ﻿

(2013)
We introduce a class of solids that can be constructed gluing stackable pieces, which has been proven to have advantages ...
• Presentation #### Stabbing simplices of point sets with k-flats ﻿

(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 ...
• Presentation #### 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 ...
• Presentation #### 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 ...
• Presentation #### Simulating distributed algorithms for lattice agents ﻿

(2013)
We present a practical Java tool for simulating synchronized distributed algorithms on sets of 2-and 3-dimensional ...
• Presentation #### 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 ...
• Presentation #### Simulated annealing applied to the MWPT problem ﻿

(2013)
The Minimum Weight Pseudo-Triangulation (MWPT) problem is suspected to be NP-hard. We show here how Simulated Annealing ...
• Presentation #### SensoGraph: Using proximity graphs for sensory analysis ﻿

(2013)
Sensory evaluation of foods is as important as chemical, physical or microbiological examinations, being specially relevant ...
• Presentation #### 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 ...
• Presentation #### 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 ...