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https://hdl.handle.net/10784/27677

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ADOMIAN DECOMPOSITION METHOD AND TAYLOR SERIES METHOD IN ORDINARY DIFFERENTIAL EQUATIONS
(2013-08-01) Sanchez, Jose Albeiro; Sanchez, Jose Albeiro; Universidad EAFIT. Departamento de Ciencias; Matemáticas y Aplicaciones
Adomian Decomposition Method for a Class of Nonlinear Problems
(Hindawi Publishing Corporation, 2011-01-01) Cano, JAS; Cano, JAS; Universidad EAFIT. Departamento de Ciencias; Matemáticas y Aplicaciones
The Adomian decomposition method together with some properties of nested integrals is used to provide a solution to a class of nonlinear ordinary differential equations and a coupled system
An alternative model to explain the vectorial capacity using as example Aedes aegypti case in dengue transmission
(Elsevier BV, 2019-01-01) Catano-Lopez A.; Rojas-Diaz D.; Laniado H.; Arboleda-Sánchez S.; Puerta-Yepes M.E.; Lizarralde-Bejarano D.P.; Catano-Lopez A.; Rojas-Diaz D.; Laniado H.; Arboleda-Sánchez S.; Puerta-Yepes M.E.; Lizarralde-Bejarano D.P.; Universidad EAFIT. Departamento de Ciencias; Matemáticas y Aplicaciones
Vectorial capacity (VC), as a concept that describes the potential of a vector to transmit a pathogen, has had historical problems related to lacks in dimensional significance and high error propagation from parameters that take part in the model to output. Hence, values estimated with those equations are not sufficiently reliable to consider in control strategies or vector population study. In this paper, we propose a new VC model consistent at dimensional level, i.e., the definition and the equation of VC have same and consistent units, with a parameter estimation method and mathematical structure that reduces the uncertainty in model output, using as a case of study an Aedes aegypti population of the municipality of Bello, Colombia. After a literature review, we selected one VC equation following biological, measurability and dimensional criteria, then we rendered a local and global sensitivity analysis, identifying the mortality rate of mosquitoes as a target component of the equation. Thus, we studied the Weibull and Exponential distributions as probabilistic models that represent the expectation of mosquitoes infective life, intending to include the best distribution in a selected VC structure. The proposed mortality rate estimation method includes a new parameter that represents an increase or decrease in vector mortality, as it may apply. We noticed that its estimation reduces the uncertainty associated with the expectation of mosquitoes' infective life expression, which also reduces the output range and variance in almost a half. Virology; Applied mathematics; Health sciences; Epidemiology; Infectious disease; Mortality; Uncertainty analysis; Vectorial capacity; Sensitivity analysis; Dengue © 2019 The Authors
Analysis of the stability and dispersion for a Riemannian acoustic wave equation
(ELSEVIER SCIENCE INC, 2019-01-15) Quiceno, H. R.; Arias, C.; Quiceno, H. R.; Arias, C.; Universidad EAFIT. Departamento de Ciencias; Matemáticas y Aplicaciones
The construction of images of the Earth's interior using methods as reverse time migration (RTM) or full wave inversion (FWI) strongly depends on the numerical solution of the wave equation. A mathematical expression of the numerical stability and dispersion for a particular wave equation used must be known in order to avoid unbounded numbers of amplitudes. In case of the acoustic wave equation, the Courant–Friedrich–Lewy (CFL) condition is a necessary but is not a sufficient condition for convergence. Thus, we need to search other types of expression for stability condition. In seismic wave problems, the generalized Riemannian wave equation is used to model their propagation in domains with curved meshes which is suitable for zones with rugged topography. However, only a heuristic version of stability condition was reported in the literature for this equation. We derived an expression for stability condition and numerical dispersion analysis for the Riemannian acoustic wave equation in a two-dimensional medium and analyzed its implications in terms of computational cost. © 2018 Elsevier Inc.
Analysis with wavelets of electrocardiographic alterations in chronic Chagas patients
(BOARD, 2013-01-01) Riveros, Fernando; Jairo A Villegas G; Riveros, Fernando; Jairo A Villegas G; Universidad EAFIT. Departamento de Ciencias; Matemáticas y Aplicaciones
article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Aplicación de un modelo de a un molino de bolas en la industria del cemento
(Fondo Editorial Universidad EAFIT, 2014-01-01) LOAIZA, GABRIEL IGNACIO; LOAIZA, GABRIEL IGNACIO; Universidad EAFIT. Departamento de Ciencias; Matemáticas y Aplicaciones
Aplicación de un modelo de balance poblacional a un molino de bolas en la industria del cemento
(Fondo Editorial Universidad EAFIT, 2014-06-01) Loaiza, G; Rivera, Ismael; Quintero, Freddy; Bustamante, Oswaldo; Loaiza, G; Rivera, Ismael; Quintero, Freddy; Bustamante, Oswaldo; Universidad EAFIT. Departamento de Ciencias; Matemáticas y Aplicaciones
En este artículo se estudia un molino rotatorio continuo para la industria del cemento. Precisamente, se emplea un modelo de balance poblacional, utilizando como ecuación constitutiva una ley de desgaste constante, con el objetivo...
An Application of Hensel's Lemma and Puiseaux series to the problem of the existence of limits of quotients of real analytic functions
(ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD, 2012-10-01) Vélez, Juan Diego; Vélez, Juan Diego; Universidad EAFIT. Departamento de Ciencias; Matemáticas y Aplicaciones
An approach to emotion Recognition in Single-channel EEG Signals using Stationary Wavelet Transform
(SPRINGER, 2017-04-01) MEJIA, GUSTAVO ANTONIO; QUINTERO, OLGA LUCIA; MEJIA, GUSTAVO ANTONIO; QUINTERO, OLGA LUCIA; Universidad EAFIT. Departamento de Ciencias; Matemáticas y Aplicaciones
Bidomain model solution using the finite volume method
(Hikari Ltd., 2016-01-01) Jairo Villegas, G.; Jorge Castaño, B.; Javier Gil, G.; Andrei González, G.; Jairo Villegas, G.; Jorge Castaño, B.; Javier Gil, G.; Andrei González, G.; Universidad EAFIT. Departamento de Ciencias; Matemáticas y Aplicaciones
In this paper we consider cardiac electrical activity through bidomain model, to describe the electrical behavior of cardiac tissue, based on current flow, electric potential distribution and conservation of charge. So we use the finite volume scheme built on rectangular meshes. Discretizing will focus on existing algorithms for elliptic and parabolic equations, with convergence guaranteed by the classical theory. © 2016 Jairo Villegas G.
Characterization of the maximal ideal of operators associated to the tensor norm defined by an Orlicz function
(HELDERMANN VERLAG, 2001-01-01) Loaiza, G; Molina, JAL; Rivera, MJ; Loaiza, G; Molina, JAL; Rivera, MJ; Universidad EAFIT. Departamento de Ciencias; Matemáticas y Aplicaciones
Given an Orlicz function H satisfying the 2 property at zero, one can use the Orlicz sequence space lH to define a tensor norm gHc and the minimal (Hc-nuclear) and maximal (Hc-integral) operator ideals associated to gHc in the sense of Defant and Floret. The aim of this paper is to characterize Hc-integral operators by a factorization theorem. © Heldermann Verlag.
Detección de puntas epilépticas en señales electroncefalográficas para pacientes con epilepsia del lóbulo temporal utilizando wavelets
(Fondo Editorial Universidad EAFIT, 2009-06-01) VILLEGAS, JAIRO ALBERTO; VILLEGAS, JAIRO ALBERTO; Universidad EAFIT. Departamento de Ciencias; Matemáticas y Aplicaciones
The direct summand conjecture for some bigenerated extensions and an asymptotic version of Koh¿s conjecture
(Springer Verlag, 2016-01-01) Gallego, Edisson; Gallego, Edisson; Universidad EAFIT. Departamento de Ciencias; Matemáticas y Aplicaciones
Early Detection for Dengue Using Local Indicator of Spatial Association (LISA) Analysis.
(MDPI, 2016-03-29) Parra, Mayra Elizabeth; M.E PUERTA; Lisarralde, Diana Paola; Arboleda, Sair; Parra, Mayra Elizabeth; M.E PUERTA; Lisarralde, Diana Paola; Arboleda, Sair; Universidad EAFIT. Departamento de Ciencias; Matemáticas y Aplicaciones
Dengue is a viral disease caused by a flavivirus that is transmitted by mosquitoes of the genus Aedes. There is currently no specific treatment or commercial vaccine for its control and prevention; therefore, mosquito population control is the only alternative for preventing the occurrence of dengue. For this reason, entomological surveillance is recommended by World Health Organization (WHO) to measure dengue risk in endemic areas; however, several works have shown that the current methodology (aedic indices) is not sufficient for predicting dengue. In this work, we modified indices proposed for epidemic periods. The raw value of the epidemiological wave could be useful for detecting risk in epidemic periods; however, risk can only be detected if analyses incorporate the maximum epidemiological wave. Risk classification was performed according to Local Indicators of Spatial Association (LISA) methodology. The modified indices were analyzed using several hypothetical scenarios to evaluate their sensitivity. We found that modified indices could detect spatial and differential risks in epidemic and endemic years, which makes them a useful tool for the early detection of a dengue outbreak. In conclusion, the modified indices could predict risk at the spatio-temporal level in endemic years and could be incorporated in surveillance activities in endemic places.
Ecuación de Clairaut: un desarrollo algebraico
(2019-10-01) GARCIA, ORLANDO; Cano, JAS; GARCIA, ORLANDO; Cano, JAS; Universidad EAFIT. Departamento de Ciencias; Matemáticas y Aplicaciones
En este artículo se presenta una forma alternativa para encontrar la solución singular de la ecuación diferencial de Clairaut, usando para ello un razonamiento algebraico.
Effects on Electricity Markets of a Demand Response Model Based on Day Ahead Real Time Prices: Application to the Colombian Case
(IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, 2018-05-01) Rivera, Juan Carlos; Paramo, Oscar Alejandro; Lopez, Gustavo Adolfo; Rivera, Juan Carlos; Paramo, Oscar Alejandro; Lopez, Gustavo Adolfo; Universidad EAFIT. Departamento de Ciencias; Matemáticas y Aplicaciones
This paper presents an alternative methodology, based on a cost optimization model, for evaluating some effects of the implementation of an alternative Demand Response (RD) program based on Day Ahead Real-Time Pricing (DA-RTP) in electricity markets. The proposed methodology has three special characteristics: the first one is to assume that users can modify their consumption patterns without altering the quantity demanded daily; second one, users flexibility to shift demand between hours depend of the kind of user and the time (peak vs off peak hours); finally, consumers have limited capability to shift demand outside of certain periods withing the day. The model is tested with a simulation exercise for the Colombian electricity market. The results show a significant improvement in system and market performance, including consumer savings, a flattened load curve, and reduced operational risk in the system. © 2003-2012 IEEE.
The Electrical Activity of Cardiac Tissue via Finite Element Method
(Hikari, 2012-06-01) VILLEGAS, JAIRO ALBERTO; VILLEGAS, JAIRO ALBERTO; Universidad EAFIT. Departamento de Ciencias; Matemáticas y Aplicaciones
Ellipse-based principal component analysis for self-intersecting curve reconstruction from noisy point sets
(SPRINGER, 2011-03-01) Ruiz, O.; Vanegas, C.; Cadavid, C.; Ruiz, O.; Vanegas, C.; Cadavid, C.; Universidad EAFIT. Departamento de Ciencias; Matemáticas y Aplicaciones
Surface reconstruction from cross cuts usually requires curve reconstruction from planar noisy point samples. The output curves must form a possibly disconnected 1-manifold for the surface reconstruction to proceed. This article describes an implemented algorithm for the reconstruction of planar curves (1-manifolds) out of noisy point samples of a self-intersecting or nearly self-intersecting planar curve C. C:[a,b]R?R 2 is self-intersecting if C(u)=C(v), u v, u,v (a,b) (C(u) is the self-intersection point). We consider only transversal self-intersections, i.e. those for which the tangents of the intersecting branches at the intersection point do not coincide (C (u)=C(v)). In the presence of noise, curves which self-intersect cannot be distinguished from curves which nearly self-intersect. Existing algorithms for curve reconstruction out of either noisy point samples or pixel data, do not produce a (possibly disconnected) Piecewise Linear 1-manifold approaching the whole point sample. The algorithm implemented in this work uses Principal Component Analysis (PCA) with elliptic support regions near the self-intersections. The algorithm was successful in recovering contours out of noisy slice samples of a surface, for the Hand, Pelvis and Skull data sets. As a test for the correctness of the obtained curves in the slice levels, they were input into an algorithm of surface reconstruction, leading to a reconstructed surface which reproduces the topological and geometrical properties of the original object. The algorithm robustly reacts not only to statistical non-correlation at the self-intersections (non-manifold neighborhoods) but also to occasional high noise at the non-self-intersecting (1-manifold) neighborhoods. © 2010 Springer-Verlag.
Erratum: Ellipse-based principal component analysis for self-intersecting curve reconstruction from noisy point sets (Visual Computer DOI: 10.1007/s00371-010-0527-x)
(SPRINGER, 2011-01-01) Ruiz, O.; Vanegas, C.; Cadavid, C.; Ruiz, O.; Vanegas, C.; Cadavid, C.; Universidad EAFIT. Departamento de Ciencias; Matemáticas y Aplicaciones
[No abstract available]
Espacios de sucesiones de orlicz l_H y representabilidad finita
(2004-01-01) LOAIZA, GABRIEL IGNACIO; LOAIZA, GABRIEL IGNACIO; Universidad EAFIT. Departamento de Ciencias; Matemáticas y Aplicaciones

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