• Times of analgesic efficacy of two drugs in the treatment of patients with renal-ureteral colic compared by survival models 

      Reyes Velázquez, Luis; Ulín Montejo, Fidel; Pérez Chavez, Jorge Alejandro; Salinas Hernández, Rosa María; Torres López, Jorge Elías (2015-01-01)
      Renourethral colic is a very painful clinical situation that requires a quick diagnosis and treatment. A study was done with patients who were administered two types of analgesics, and whose pain was measured through a ...
    • Transmission dynamics of Dengue in Costa Rica: The role of hospitalizations 

      Sánchez Peña, Fabio Ariel; Arroyo Esquivel, Jorge; Vásquez Brenes, Paola Andrea (2019-12)
      For decades, dengue virus has caused major problems for public health officials in tropical and subtropical countries around the world. We construct a compartmental model that includes the role of hospitalized individuals ...
    • Triángulos casi congruentes 

      Piza Volio, Eduardo (2012-03-29)
      En este artículo se estudian los triángulos casi congruentes, que consisten en las parejas de triángulos que tienen exactamente 5 de sus 6 elementos congruentes. Se caracterizan todas las soluciones enteras a este problema. ...
    • Ttsunami. An Interesting Mathematical Problem 

      González González, Rodrigo; Ortiz Figueroa, Modesto; Montoya Rodríguez, José Miguel (2012-03-12)
      We present some key aspects regarding the mathematics and the computational tool that support the complex description of the physical process tsunami from two specific approaches. In particular, it addresses analytically ...
    • Ultraproductos de f-anillos proyectables 

      Guier Acosta, Jorge Ignacio (2009-02-18)
      In [7], Keimel representes the projectable f-rings as continuous sections of Hausdorff sheaves of totally ordered rings. Here, we give a result about the representation of ultraporducts of projectable f-rings in terms of ...
    • Un Algoritmo Evolutivo para Resolver el Problema de Coloración Robusta 

      Lara Velázquez, Pedro; Gutiérrez Andrade, Miguel Ángel; Ramírez Rodríguez, Javier; López Bracho, Rafael (2012-03-22)
      Let G and \bar{G} be two complementary graphs. Given a penalty function defined over the edges of \bar{G}, it is said that the rigidity of a k-coloring of G is the summation ofthe penalties of the edges of G that join ...
    • Un algoritmo para el entrenamiento de máquinas de vector soporte para regresión 

      Goddard Close, John; de los Cobos Silva, Sergio Gerardo; Pérez Salvador, Blanca Rosa; Gutiérrez Andrade, Miguel Ángel (2009-02-19)
      The aim of the present paper is twofold. Firstly an introduction to the ideas of Support Vector regression is given. then a new and simple algorithm, suggested by the work of Campbell y Cristianini in [16], is proposed ...
    • Un algoritmo paralelo para el problema del conjunto independiente 

      López Bracho, Rafael; Ortuño Sánchez, María Paula (2009-02-19)
      Un conjunto S de vértices de una gráfica G es independiente si no existen dos vértices de S que sean adyacentes, esto es, la subgráfica de G inducida por S no tiene aristas. En este trabajo presentaremos un algoritmo ...
    • Un análisis factorial de la asociación disimétrica entre dos variables cualitativas 

      Abdesselam, Rafik; Schektman, Yves (2012-03-29)
      Asymmetrical “relational association coefficients” are described. Measurements of these coefficients are expressed as inertia in the individual–space with a “relational inner product”. This geometrical and mechanical point ...
    • Un enfoque diferente de las técnicas de clustering para el estudio de epidemias 

      Casas Cardoso, Gladys M.; Grau Abalo, Ricardo (2009-02-18)
      Classification of an outbreak with the category of epidemics requires that some epidemiological and statistical parameters, which have to be studied simultaneously, are satisfied; mathematical theory helps epidemiologists ...
    • Un frailty aditivo en modelos de supervivencia bivariante 

      Navarrete Álvarez, Esteban; García Leal, Julia; Lara Porras, Ana María (2009-02-18)
      Bivariate survival models based on the presence of an unobseved random covariate, grailty, tend to assume a proportional hazard hypothesis. A bivariate survival model is constructed. It is based on frailty model that acts ...
    • Un método para la caracterización exhaustiva de formas de figuras planas, tanto simple como múltiplemente conexas 

      Skliar, Osvaldo; Medina, Víctor; Poveda, José S. (2009-02-20)
      This article presents a method with which the shapes of plane figures may becharacterized exhaustively by using descriptive mathematical entities obtained fromthese figures. They may be either simply or multiply connected. ...
    • un modelo de equilibrio para economías de producción con análisis de actividad 

      Acuña Ortega, Osvaldo (2009-02-20)
      In this paper we study a general equilibrium model for economies with activitiesanalysis production technologies and we prove a global index theorem for regulareconomies.Keywords: Regular economy, economic equilibrium, ...
    • Un Modelo Matemático para la bola de Fútbol 

      Escalante, René; Pacheco, Francisco (2012-03-01)
      This work refers to the analysis, study and resolution of the mathematical problem involved in the design and construction of the cover of a ball, such as the ones used in sports, in order to achieve a ball with optimal ...
    • Un problema de localización de plantas de gran escala 

      Gutiérrez Andrade, Miguel Ángel; de los Cobos Silva, Sergio Gerardo; Pérez Salvador, Blanca Rosa; Goddard Close, John (2009-02-19)
      En este artículo se desarrolla un algoritmo heurístico y su correspondiente implementación para resolver un problema de localización de plantas (facility location) de gran escala, en donde surgen potencialmente más de 640 ...
    • Un procedimiento de fuerte reducción de las dimensiones del RCPS/Pi 

      Álvarez Valdés Olaguíbel, Ramón; Crespo, Enric; Tamarit Goerlich, José Manuel; Villa Juliá, M. Fulgencia (2009-02-27)
      Recently, in the field of project scheduling problems the concept of partially renewableresources has been introduced. Theoretically, it is a generalization of both renewable and non-renewable resources. From an applied ...
    • Una caracterización sobre las soluciones para el problema de reaprovisionamiento conjunto 

      de los Cobos Silva, Sergio Gerardo; Gutiérrez Andrade, Miguel Ángel; Goddard Close, John; Pérez Salvador, Blanca Rosa (2009-02-20)
      In this paper an introduction is given to a multiple-item inventory problem, knownas the Joint Replenishment Problem (JRP). This is a real world problem which hasbeen extensively studied. The JRP has a continuous decision ...
    • Una noción de proceso puntual en tiempo discreto 

      Lobo Segura, Jaime (2012-03-21)
      Luego de señalar las dificultades de la teoría clásica en el tratamiento de los procesos puntuales sobre la recta, se da una noción de proceso puntual en tiempo discreto cuya definición reposa sobre conceptos del análisis ...
    • Una propuesta de Modelamiento para los Sistemas de Recompensa 

      de los Cobos Silva, Sergio Gerardo; Brunet Icart, Ignasi; Pérez Salvador, Blanca Rosa; González Santoyo, Federico; Flores Romero, Beatriz (2012-03-01)
      One of the most important subjects of interest, in nearly any human activity, is the perception of salary. It could even be said that the decision of following a career depends deeply on the perspective that the individual ...
    • Una variante del método que utiliza la simulación de un proceso de difusión para la caracterización de formas de figuras planas 

      Skliar, Osvaldo; Láscaris Comneno, Tatiana; Medina, Víctor; Poveda, José S. (2009-02-20)
      This is a variation of a previously presented method [1] for characterizing the shapesof plane figures. In addition to retaining the advantages of the original method, thisvariant includes one more: it is no longer necessary ...