Noticias en español
Seminars appear in decreasing order in relation to date. To find an activity of your interest just go down on the list. Normally seminars are given in English. If not, they will be marked as Spanish Only.
Uso de GIS en Plataformas Web
Seminarios de la Alianza Copernicus-Chile Titulo Uso de GIS en Plataformas Web Expositor Carlos Patillo CPRSIG Ltda. Fecha: Lunes 13 de Mayo de 2019 Hora inicio: 16:00 horas Lugar: Sala Multimedia, Centro de Modelamiento Matemático, Facultad de Ciencias Físicas y Matemáticas, Universidad de Chile. Beauchef 851, Santiago – Edificio Norte, Piso 6 Participación en Linea: http://vcespresso.redclara.net/@352109705c115cdd511fb968f9f4ff86# Use Explorer, Firefox o Safari. Debe tener instalado Flash Player en su...
Generalizations of the geometric de Bruijn Erdős Theorem
Abstract: A classic Theorem of de Bruijn and Erdős states that every noncollinear set of n points in the plane determines at least n distinct lines. The line L(u, v) determined by two points u, v in the plane consists of all points p such that dist(p, u) + dist(u, v) = dist(p, v) (i.e. u is between p and v) or • dist(u, p) + dist(p, v) = dist(u, v) (i.e. p is between u and v) or • dist(u, v) + dist(v, p) = dist(u, p) (i.e. v is between u and p). With this definition of line L(uv) in an arbitrary metric space (V, dist), Chen and Chvátal...
Decay of small odd solutions of the long range Schrödinger and Hartree equations in one dimension.
Abstract: We consider the long time asymptotics of (not necessarily small) odd solutions to the nonlinear Schrödinger equation with semilinear and nonlocal Hartree nonlinearities, in one dimension space. We assume data in the energy space only and we prove decay to zero in compact regions of space as time tends to infinity. We give three different results were decay holds: NLS without potential, NLS with potential and Hartree (defocusing case). The proof is based in the use of suitable virial identities and covers all range of scattering...
Enhancing Mathematics Instruction to Facilitate Student Participation: Studying Elementary Classrooms Using Head-Mounted Cameras
Resumen: During the talk participants will view video clips filmed by third grade students who wore head-mounted cameras and discuss an intervention that helped teachers learn about how to support the development of mathematics and student interactions.
Cost functionals for large random trees
Abstract : Additive tree functionals allow to represent the cost of many divide-and-conquer algorithms. We give an invariance principle for such tree functionals for the Catalan model and for simply generated trees . In the Catalan model, this relies on the natural embedding into the Brownian excursion. (Joint work with Jean-François Delmas and Marion Sciauveau)
ALMOST DESCRIPTION OF DECAY FOR HAMILTONIAN ABCD SYSTEM CHULKWANG KWAK
ABSTRACT The Boussinesq abcd system was originally derived by Bona, Chen and Saut [J. Nonlinear. Sci. (2002)] as first order 2-wave approximations of the incompressible and irrotational, two dimensional water wave equations in the shallow water wave regime. Among many particular regimes, the Hamiltonian generic regime is characterized by the setting b = d > 0 and a,c < 0. It is known that the system in this regime is globally well-posed for small data in the energy space H1 × H1 by Bona, Chen and Saut [Nonlinearity (2004)]. In this...
Finding 2-factors without triangles
Abstract: A 2-factor is a set of edges M of a graph G such that each vertex is incident to exactly two edges of M. Thus M determines a set of cycles in G. One can efficiently compute minimum cost 2-factors in weighted graphs. It is open whether one can do the same, if we forbid triangles, i.e., each cycle has at least four edges. For the unweighted case, a complicated result of Hartvigsen shows that one can find such a 2-matching in polynomial time. In the talk, we will review known results related to finding triangle free...
Liouville dynamical percolation & The signature method
Seminario doble conjunto Modelamiento Estocástico / Núcleo Milenio MESCYD Primera Sesión: 3pm Avelio Sepúlveda (U. Lyon 1) Liouville dynamical percolation A dynamical percolation is a process on black and white colourings of the vertices of a graph, in which each vertex has an independent Poissonian clock, and each time a clock rings the colour of its correspondent vertex is resampled. In this talk, we will study a dynamical percolation in the triangular grid, using clocks whose rate is defined in terms of a Liouville measure of parameter...
