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Mostrando ítems 1-10 de 14
Artículo
Bifurcation from zero of a complete trajectory for non-autonomous logistic PDEs
(World Scientific Publishing, 2005-08)
In this paper we extend the well-known bifurcation theory for autonomous logistic equations to the non-autonomous equation ut − ∆u = λu − b(t)u 2 with b(t) ∈ [b0, B0], 0 < b0 < B0 < 2b0. In particular, we prove the ...
Artículo
Study of an elliptic system arising from angiogenesis with chemotaxis and flux at the boundary
(Elsevier, 2008-06-15)
The main goal of this paper is to study a stationary problem arising from angiogenesis, including terms of chemotaxis and flux at the boundary of the tumor. We give sufficient conditions on terms of the data of the problems ...
Artículo
Existence of a positive solution for a singular system
(Cambridge University Press, 2010-04)
We show the existence and nonexistence of positive solutions to a system of singular elliptic equations with Dirichlet boundary condition. This system arises in studies of pattern formation in biology and in the ...
Artículo
Permanence and asymptotically stable complete trajectories for nonautonomous Lotka-Volterra models with diffusion
(Society for Industrial and Applied Mathematics, 2009)
Lotka-Volterra systems are the canonical ecological models used to analyze population dynamics of competition, symbiosis or prey-predator behaviour involving different interacting species in a fixed habitat. Much of the ...
Artículo
A logistic equation with degenerate diffusion and Robin boundary condition
(American Institute of Mathematical Sciences, 2008-09)
In this paper we study a model for a species confined in a bounded region. This species diffuses slowly, follows a logistic law in the habitat and there is a flux of population across the boundary of the habitat. Basically, ...
Ponencia
Algunos modelos estacionarios de dinámica de poblaciones estructurados en edad con difusión
(2004)
En este trabajo, daremos algunos resultados de existencia y unicidad de solución para un problema de dinámica de poblaciones estructurado en edad con difusión. Primero describiremos un método de sub-supersolución para este ...
Artículo
Bifurcations in non-autonomous scalar equations
(Elsevier, 2006-02)
In a previous paper we introduced various definitions of stability and instability for non-autonomous differential equations, and applied these to investigate the bifurcations in some simple models. In this paper we ...
Artículo
Existence and nonexistence of unbounded forward attractor for a class of non-autonomous reaction diffusion equations
(American Institute of Mathematical Sciences, 2007)
The goal of this work is to study the forward dynamics of positive solutions for the nonautonomous logistic equation ut − ∆u = λu − b(t)up, with p > 1, b(t) > 0, for all t ∈ R, limt→∞ b(t) = 0. While the pullback asymptotic ...
Artículo
Positive solutions of a system arising from angiogenesis
(De Gruyter, 2008-11)
We study a system of equations arising from angiogenesis which contains a nonregular term that vanishes below a certain threshold. This loss of regularity forces one to modify the usual methods of bifurcation theory. ...
Artículo
The competition between incoming and outgoing fluxes in an elliptic problem
(World Scientific, 2007)
In this work we consider existence and uniqueness of positive solutions to the elliptic equation −∆u = λu in Ω, with the nonlinear boundary conditions ∂u ∂ν = u p on Γ1, ∂u ∂ν = −u q on Γ2, where Ω is a smooth bounded ...