Recent Submissions

  • Differentially closed fields of characteristic zero with a generic automorphism 

    Bustamante Medina, Ronald F. (2009-02-25)
    Hrushovski showed that the theory of difference-differential fields of characteristiczero has a model-companion, which we shall denote DCFA. We give an axiomatizationfor DCFA and prove some important model-theoretic results ...
  • A note on Dirichlet and Fejér kernels 

    López Bonilla, José; Vidal Beltrán, Sergio; Yalja Montiel, Jesús (2009-02-25)
    We exhibit a trigonometric identity wich implies a link between the kernels ofDirichlet and Fejér.
  • Caracterización de espacios de Banach mediante desigualdades y el mapeo de dualidad 

    Ugalde Gómez, William Javier (2009-02-25)
    Using a result of C. E. Chidume, we present a shorter and improved proof of aresult of Xu and Roach on characterization of uniformly convex and uniformly smoothBanach spaces by the duality map and inequalities involving ...
  • Valores propios asociados al operador de Hill unidimensional. Caso general. 

    Cambronero, Santiago; Alfaro, Marco (2009-02-25)
    We study Hill’s equation with general boundary conditions and white noise potential.In [3] they solve the problem with Dirichlet conditions, leaving the general case unresolved.The problem is important both from the ...
  • Estudio de opinión sobre el T.L.C. con EE.UU. 

    Poltronieri Vargas, Jorge (2009-02-25)
    We expose the results of an opinion survey on the Free Trade Agreement with theUnited States of America. The technique of Principal Component Analysis helped usto reveal the subjacent opinion in the Costarican comunity. ...
  • Selección de Personal mediante Redes Neuronales Artificiales 

    Acevedo Orduña, German Leonardo; Caicedo Bravo, Eduardo Francisco; Loaiza Correa, Humberto (2011-04-29)
    We study the personnel selection problem by the application of techniques of computing intelligence for the classification of psychological patterns. The system is based on the psychological test 16-PF, for the extraction ...
  • The Black-Scholes type financial models and the arbitrage opportunities 

    Sukhomlin, Nikolay (2009-02-25)
    By using the conservation laws concept, we study certain financial models similar tothe Black–Scholes model. We show that without complement limitations such modelscan have two or more volatilities. This fact imposes several ...