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Artículo
On the existence and multiplicity of positive solutions for some indefinite nonlinear eigenvalue problem
(American Mathematical Society, 2004-06)
This paper concerns with the existence, uniqueness and/or multiplicity, and stability of positive solutions of an indefinite weight elliptic problem with concave or convex nonlinearity. We use mainly bifurcation method to ...
Artículo
On the controllability of the heat equation with nonlinear boundary Fourier conditions
(Elsevier, 2004-01-20)
In this paper we analyze the approximate and null controllability of the classical heat equation with nonlinear boundary conditions of the form ∂y ∂n + f(y) = 0 and distributed controls, with support in a small set. We ...
Artículo
Study of the optimal harvesting control for an elliptic problem with slow diffusion
(Sociedade Brasileira de Matemática, 2007)
In this paper our aim is to present a survey of known results of an optimal control problem with concave non-quadratic cost functional and a state equation arising from population dynamics. First, we study in detail the ...
Artículo
Age-dependent diffusive Lotka-Volterra type systems
(Elsevier, 2007-03)
In this paper it is shown that the sub-supersolution method works for age-dependent diffusive nonlinear systems with non-local initial conditions. As application, we prove the existence and uniqueness of positive solution ...
Artículo
A model for two coupled turbulent fluids. Part II: numerical analysis of a spectral discretization
(Society for Industrial and Applied Mathematics, 2002)
We consider a system of equations that models the stationary flow of two immiscible turbulentfluids on adjacentsubdomains. The equations are coupled by nonlinear boundary conditions on the interface which is here a fixed ...
Artículo
Existence and uniqueness of positive solution of a logistic equation with nonlinear gradient term
(Cambridge University Press, 2007-06)
The main goal of this work is to study the existence and uniqueness of positive solution of a logistic equation including a nonlinear gradient term. In particular, we use local and global bifurcation together with some ...
Artículo
Existence and uniqueness of positive large solutions to some cooperative elliptic systems
(De Gruyter, 2003-05)
In this work we consider positive solutions to cooperative elliptic systems of the form −∆u = λu−u2 +buv, −∆v = µv −v2 +cuv in a bounded smooth domain Ω ⊂ RN (λ, µ ∈ R, b, c > 0) which blow up on the boundary ∂Ω, that is ...
Artículo
Inclusiones diferenciales, matemática difusa y aplicaciones
(Sociedad Española de Matemática Aplicada, 2003-06)
En este trabajo diremos cómo se pueden modelar ciertos sistemas tomados de la realidad que usan conceptos propios de la Matemática Difusa (conjuntos, multifunciones e inclusiones diferenciales “fuzzy”). Consideraremos ...
Artículo
Nonnegative solutions for a heterogeneous degenerate competition model
(Cambridge University Press, 2004-10)
This paper deals with the existence, uniqueness and qualitative properties of nonnegative and nontrivial solutions of a spatially heterogeneous Lotka-Volterra competition model with nonlinear diffusion. We give conditions ...
Artículo
Análisis de algunos modelos de dinámica de poblaciones no lineales estructurados en edad y espacio
(Sociedad Española de Matemática Aplicada, 2005)
En este trabajo estudiamos modelos de la dinámica de poblaciones estructurados en edad con difusión. Construiremos un método de subsupersolución y veremos que, efectivamente, bajo la hipótesis de la existencia de un par ...