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.
La reflexión docente ante el desempeño de los estudiantes en la evaluación de sus aprendizajes matemáticos
Resumen: Este trabajo se enmarca en un enfoque sobre reflexividad (Shön, 1998), su principal propósito es describir las prácticas reflexivas de los docentes cuando analizan desempeños de aprendizaje matemático de sus estudiantes. Se usó la técnica de pensamiento en voz alta para registrar y detectar las reflexiones de seis docentes de la región Metropolitana mientras analizaban los desempeños de sus estudiantes al corregir una evaluación de aprendizaje. Posteriormente, se usó un análisis de contenido para levantar categorías que permitieran...
Restrictions on the group of automorphisms preserving a minimal subshift
ABSTRACT : A subshift is a closed shift invariant set of sequences over a finite alphabet. An automorphism is an homeomorphism of the space commuting with the shift map. The set of automorphisms is a countable group generally hard to describe. We will present in this talk a survey of various restrictions on these groups for zero entropy minimal subshifts.
Well-posedness and long time behavior for the Schrödinger-Korteweg-de Vries interactions on the half-Line
Abstract: In this talk we discuss about the initial-boundary value problem for the Schrödinger-Korteweg-de Vries system on the left and right half-line for a wide class of initial-boundary data, including the energy regularity H1(R±) × H1(R±) for initial data. Assuming homogeneous boundary conditions it is shown for positive coupling interactions that local solutions can be extended globally in time for initial data in the energy space; furthermore, for negative coupling interactions it was proved, for a certain class of regular initial...
On the action of the semigroup of non singular integral matrices on $\R^n$
Abstract. Let Γ be the multiplicative semigroup of all n × n matrices with integral entries and nonzero determinant. Let 1 ≤ p ≤ n−1 and V = Rnp = Rn ⊕···⊕Rn (p copies). Consider the action of Γ on V , given by the natural action on each component, by matrix multiplication on the left. Then for x= (x1, . . . , xp) ∈ V , the Γ-orbit is dense in V if and only if there is no linear combination pj=1 λjxj, with λj ̸= 0 for some j, which is a rational vector in Rn; in fact the assertion holds also for the orbit of the subgroup SL(n, Z) that...
Decidability of the isomorphism and the factorization for minimal substitution subshifts
ABSTRACT Classification is a central problem in the study of dynamical systems, in particular for families of systems that arise in a wide range of topics. Hence it is important to have algorithms deciding wether a dynamical system have some given property. Let us mention subshifts of finite type that appear, for example, in information theory, hyperbolic dynamics, $C^*$-algebra, statistical mechanics and thermodynamic formalism. The most important and longstanding open problem for this family originates in [Williams:1973] and is stated in...
Resonances in deformed tubes: twisting and bending & Gross-Pitaevskii equation and integrable systems
16:00 hrs. Expositor Pablo Miranda, (USach) Título Resonances in deformed tubes: twisting and bending Abstract: In this talk we will consider an infinite straight tube and we will deform it by a periodic twisting and a local bending. On the deformed tube we will define the Laplacian and will study the existence of scattering resonances created by the deformations. We will show the existence of exactly one resonance or one eigenvalue near the bottom of the essential spectrum, depending on the strength of the twisting and the bending. We...
An approach to optimality in convex optimization via some new Moreau- Rockafellar type formulas for the subdifferential of the supremum function.
Abstract: We present different characterizations of the subdifferential of the supremum function of finitely and infinitely indexed families of convex functions under weak continuity assumptions. The resulting formulas are given in terms of the exact subdifferential of the data functions at the reference point, and not at nearby points. Based on these characterizations we give new Fritz-John and KKT-type optimality conditions for semi-infinite convex optimization, dropping out the typical continuity/closedness assumptions which are usual in...
Confort y la calidad climática en el Espacio Público. Estudio de caso: ciudad de Chillán, Chile
Seminarios de la Alianza Copernicus-Chile Titulo Confort y la calidad climática en el Espacio Público. Estudio de caso: ciudad de Chillán, Chile Expositor Pamela Smith U. de Chile Sala: Sala Multimedia, Centro de Modelamiento Matemático, Beauchef 851, Edificio Norte, Piso 6. Fecha: Lunes 05 de Noviembre de 2018 Hora: 16:00 horas Participación en Linea: http://vcespresso.redclara.net/@352109705c115cdd511fb968f9f4ff86# Use Explorer, Firefox o Safari, debe tener instalado Flash Player...
