Now showing items 1-20 of 312

    • A comparison of approximations to percentiles of the noncentral chi2-distribution 

      Sahai, Hardeo; Ojeda, Mario Miguel (2009-02-20)
      Various approximations to percentiles of the noncentral 2-distribution are examinedfor their accuracy over a wide range of values of the parameters of the distribution.Keywords: Probability distribution, percentiles, ...
    • A dichotomous property of the total variation of a process with independent increments 

      Lobo Segura, Jaime (2009-02-19)
      We establish a property for the total variation of a cad-lag process with independent increments wich is dichotomous in the sense that only two alternatives are possible. For this purpose we introduce the methods of ...
    • A formula for complex zonal polynomials of second order 

      Caro Lopera, Francisco J.; González Farías, Graciela; Díaz García, José A. (2009-02-20)
      A formula for complex zonal polynomials of second order is derived by solving aparticular partial differential equation.Keywords: Laplace-Beltrami operator, zonal polynomials, Hermitian matrix, Legendre’sdifferential equation.
    • A genetic algorithm in a schedule problem with special constraints 

      Pérez de la Cruz, Carlos; Ramírez Rodríguez, Javier (2011-07-08)
      Ramírez (2001) introduced the generalized robust coloring problem (GRCP), this problem lets solve timetabling problems which considers constraints such as: two events can not be assigned at the same time and there must be ...
    • A Hybrid Random Number Generator(HRNG) 

      Skliar, Osvaldo; Monge, Ricardo E.; Medina, Víctor; Gapper, Sherry; Oviedo, Guillermo (2011-07-29)
      The purpose of this paper is to present a novel Hybrid Random Number Generator (HRNG). Here “hybrid” refers to the fact that to construct this generator it is necessary to use 1)physical components – texts – and a physical ...
    • A method for analyzing turbulence models 

      Grebene, V. N.; Ilyushin, B. B. (2009-02-19)
      In this article we introduce a concept based on the differential constraints methodto examine the closure procedure in Turbulence Models. We show how this conceptmay be applied to study the problem of interaction and mixing ...
    • A mimetic finite difference method using Crank-Nicolson scheme for unsteady diffusion equation 

      Mannarino, Iliana A. (2010-04-09)
          n this article a new mimetic finite difference method to solve unsteady diffusionequation is presented. It uses Crank-Nicolson scheme to obtain time approximationsand second order mimetic discretizations for gradient ...
    • A mixed-effects model for growth curves analysis in a two-way crossed classification layout 

      Ojeda, Mario Miguel; Sahai, Hardeo (2009-02-20)
      We propose a mixed-effects linear model for analyzing growth curves data obtainedusing a two-way classification experiment. The model combines an unconstrainedmeans model and a regression model on the time, in which the ...
    • A multistep fundamental solution scheme for modeling groundwater flow 

      Guevara Jordan, Juan M.; Da Silva Rodrigues, Carmen M. (2009-02-27)
      A new numerical scheme for solving transient pressure in a confined aquifer ispresented. It is based on the fundamental solution method (FSM) and it combinesfree Green functions, superposition principle, and singular value ...
    • A new method for the analysis of images: the square wave method 

      Skliar, Osvaldo; Oviedo, Guillermo; Monge, Ricardo E.; Medina, Víctor; Gapper, Sherry (2013-08-29)
      The Square Wave Method (SWM) – previously applied to the analysis of signals – has been generalized here, quite naturally and directly, for the analysis of images. Each image to be analyzed is subjected to a process of ...
    • A Non-Standard Generating Function for Continuous Dual q-Hahn polynomials 

      Atakishiyeva, Mesuma; Atakishiyev, Natig (2011-03-18)
      We study a non-standard form of generating function for the three-parameter continuous dual q-Hahn polynomials $p_{n} (x; a, b, | q)$, which has surfaced in a recent work of the present authors on the construction of lifting ...
    • A note on $k$-finite objects in a boolean topos with the natural numbers object 

      Acuña Ortega, Osvaldo (2012-07-01)
      We prove that every $k$-finite object in a boolean topos with nat-ural number object is internally the quotient of a natural number object.Keywords: Topoi, $k$-finite objects, natural numbers.Mathematics Subject Classification: ...
    • 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.
    • A Tabu search Approach for the Weighted Tardiness with Sequence-Dependent Setups in one-machine Problem 

      Beausoleil, Ricardo P. (2011-04-29)
      In this paper, a Tabu Search Approach for the weighted tardiness single machine problem with sequence-dependent setups is proposed. The main contribution is the balance obtained between intensification and diversification ...
    • About the exact and asymptotic distribution of the Gini coefficient 

      Martínez Camblor, Pablo; Corral, Norberto (2010-04-09)
      In this paper we deal with the distribution of the Gini Concentration Index (G).We derive its exact sample distribution which is useful only for small sample sizesand basing on the classic results for L-statistics of Egorov ...
    • ACCPlot: gráficos del ACP con Mathematica 

      Arce Salas, Carlos (2009-02-18)
      ACPPlot is a command for creating graphics for Principal Component Analysis (PCA), principal planes and correlation circles; in both cases, adding options for joining points with trajectories, clustering points, labeling ...
    • Agrupamiento de Filas y Columnas Homogéneas en Modelos de Correspondencia 

      Marinelli, Claudia; Winzer, Nélida (2011-04-29)
      Goodman(1981) proposed homogeneity and structures criterias in Associaton Models which allow to determine if certain rows or columns in a contingency table should be grouped. In later works, he showed the relations between ...
    • Ajuste de un modelo VAR como predictor de los campos de anomalías de precipitación en centroamérica 

      Alfaro Martínez, Eric J.; Soley Alfaro, Francisco Javier (2012-04-26)
      Cluster analysis was used to identify common patterns of 15 precipitation points of the region, using their anomaly time series as grouping variables. Five clusters where identified through this process. A Vector Auto ...
    • Algebraic jet spaces and Zilber’s dichotomy in DCFA 

      Bustamante Medina, Ronald F. (2010-04-16)
      This is the first of two papers devoted to the proof of Zilber’s dichotomy for the case of difference-differential fields of characteristic zero. In this paper we use the techniques exposed in [9] to prove a weaker version ...
    • Algoritmo de búsqueda tabú para una variante del problema de coloración 

      Aboytes Ojeda, Mario; Laureano Cruces, Ana Lilia; Ramírez Rodríguez, Javier (2013-08-29)
      El problema de coloración robusta generalizado (PCRG) resuelve problemas de horarios que consideran restricciones especiales. Al ser una generalización del problema de coloración robusta, que es a su vez una generalización ...