Now showing items 1-20 of 61

    • A brief survey of Higgs bundles 

      Zúñiga Rojas, Ronald Alberto (2019-06)
      Considering a compact Riemann surface of genus greater or equal than two, a Higgs bundle is a pair composed of a holomorphic bundle over the Riemann surface, joint with an auxiliar vector field, so-called Higgs field. This ...
    • A Geometric Splitting Theorem 

      Rosales Ortega, José (2019)
      Let G = G1...Gl be a connected noncompact semisimple Lie group with Lie algebra g = g_1+g_2+....+ g_l acting topologically transitive on a manifold M. We obtain a geometric splitting of the metric on M that consider ...
    • A two-level overlapping Schwarz method for H(curl) in two dimensions with irregular subdomains 

      Calvo Alpízar, Juan Gabriel (2015-10-07)
      A bound is obtained for the condition number of a two-level overlapping Schwarz algorithm for problems posed in H(curl) in two dimensions, where the subdomains are only assumed to be John subdomains. The coarse space is ...
    • An adaptive choice of primal constrains for BDDC domain decomposition algorithms 

      Calvo Alpízar, Juan Gabriel; Widlund, Olof B. (2016-12-12)
      An adaptive choice for primal spaces based on parallel sums is developed for BDDC deluxe methods and elliptic problems in three dimensions. The primal space, which forms the global, coarse part of the domain decomposition ...
    • Analyzing the Measurement Equivalence of a Translated Test in a Statewide Assessment Program 

      Carvajal Espinoza, Jorge Eduardo; Welch, Greg W. (2016-09)
      When tests are translated into one or more languages, the question of the equivalence of items across language forms arises. This equivalence can be assessed at the scale level by means of a multiple group confirmatory ...
    • Asymptotic expansion of the invariant measure for ballistic random walk in the low disorder regime 

      Campos Fernández, José David; Ramírez Chuaqui, Alejandro Francisco (2015)
      We consider a random walk in random environment in the low disorder regime on Zd. That is, the probability that the random walk jumps from a site x to a nearest neighboring site x+e is given by p(e)+ǫξ(x,e), where p(e) is ...
    • Clifford Geometry: a Seminar 

      Várilly Boyle, Joseph C.; Gracia Bondía, José M. (1995-12-15)
      Este documento fue desarrollado durante el seminario de posgrado SP--1313 (Seminario en Matemática A) en 1995; por razones de difusión, fue redactado en inglés. Se trata de una exposición de los aspectos de la geometría ...
    • Comparative analysis of dengue versus chikungunya outbreaks in Costa Rica 

      Sánchez Peña, Fabio Ariel; Barboza Chinchilla, Luis Alberto; Burton, David; Cintrón Arias, Ariel (2018-06)
      For decades, dengue virus has been a cause of major public health concern in Costa Rica, due to its landscape and climatic conditions that favor the circumstances in which the vector, Aedes aegypti, thrives. The emergence ...
    • Contribuciones al estudio de las métricas en análisis de datos 

      Bolaños Guerrero, Fabricio (2012-10-25)
      Nos hemos planteado estudiar la dependencia de los resultados al cambiar las métricas para el mtodo de Análisis en Componentes Principales (A.C.P.). En efecto, para este análisis el problema de la escogencia de la distancia ...
    • Correction to: The chirality theorem 

      Gracia Bondía, José M.; Mund, Jens; Várilly Boyle, Joseph C. (2018-10)
    • Definable Additive Subgroups of Partial Differential Fields of Characteristic Zero with an Automorphism 

      Bustamante Medina, Ronald F. (2020-10-19)
      Abstract.The theory of partial differential fields of characteristic zero withan automorphism has a model companion denoted DCFmA. This theory isnot complete, but its completions are easily discribed. They are supersimpleand ...
    • Domain Decomposition Methods for Problems in H(curl) 

      Calvo Alpízar, Juan Gabriel (2015-05)
      Two domain decomposition methods for solving vector field problems posed in H(curl) and discretized with Nedelec finite elements are considered. These finite elements are conforming in H(curl). A two-level overlapping ...
    • Drinking as an epidemic - a simple mathematical model with recovery and relapse 

      Sánchez Peña, Fabio Ariel; Wang, Xiaohong; Castillo Chávez, Carlos; Gorman, Dennis M.; Gruenewald, Paul J. (2007)
      This chapter discusses a simple mathematical model of drinking lapse. Problem drinking is modeled as an acquired state - the result of frequent or intense interactions among individuals in three drinking states within a ...
    • Faltings heights of CM elliptic curves and special Gamma values 

      Barquero Sánchez, Adrián Alberto; Cadwallader, Lindsay; Cannon, Olivia; Genao, Tyler; Masri, Riad (2017-12)
      In this paper, we evaluate the Faltings height of an elliptic curve with complex multiplication by an order in an imaginary quadratic field in terms of Euler’s Gamma function at rational arguments.
    • La geometría en su contexto histórico 

      Várilly Boyle, Joseph C. (Las Matemáticas y su Enseñanza 6(17):21–34, 1995 octubre, 1995-10-15)
      La geometría en los sistemas de enseñanza media ha sido retomado por diversas propuestas para remozar los programas de matemáticas; y en el caso de Costa Rica, con la puesta en práctica de un programa ambicioso que destaca ...
    • Los grupos clásicos y su clasificación 

      Várilly Boyle, Joseph C. (Coloquios de Matemática., 2011-08-10)
      Esta es la memoria de un coloquio en la Escuela de Matemática, el 10 de agosto del 2011, en la ocasión de la visita a la UCR del Profesor Luis Joaquín Boya, de Zaragoza. Es un bosquejo de la clasificación de los grupos ...
    • ¿Ha escuchado del Dengue, Zika o Chikungunya? 

      Vásquez Brenes, Paola Andrea; Sánchez Peña, Fabio Ariel (2020)
      ¿Ha escuchado del Dengue, Zika o Chikungunya? Ese es el nombre de las enfermedades que yo, el mosquito Aedes aegypti puedo transmitir cada vez que me alimento.Vivo en lugares con agua estancada, esos son mis favoritos, ahí ...
    • Improved Automatic Centerline Tracing for Dendritic and Axonal Structures 

      Jiménez López, David Adrián; Labate, Demetrio; Kakadiaris, loannis A.; Papadakis, Manos (2015-04)
      Centerline tracing in dendritic structures acquired from confocal images of neurons is an essential tool for the construction of geometrical representations of a neuronal network from its coarse scale up to its fine scale ...
    • Isometry groups of borel randomizations 

      Berenstein, Alex; Zamora Calero, Rafael (2018-08)
      We study global dynamical properties of the isometry group of the Borel randomization of a separable complete structure. In particular, we show that if properties such as the Rohklin property, topometric generics, extreme ...