Digital Library
Close Browse articles from a journal
 
<< previous    next >>
     Journal description
       All volumes of the corresponding journal
         All issues of the corresponding volume
           All articles of the corresponding issues
                                       Details for article 50 of 69 found articles
 
 
  Positive Solutions to Semilinear Elliptic Equations with Logistic Type Nonlinearities and Constant Yield Harvesting in N
 
 
Title: Positive Solutions to Semilinear Elliptic Equations with Logistic Type Nonlinearities and Constant Yield Harvesting in N
Author: Costa, David G.
Drabek, Pavel
Tehrani, Hossein T.
Appeared in: Communications in partial differential equations
Paging: Volume 33 (2008) nr. 9 pages 1597-1610
Year: 2008-09
Contents: We consider a class of semilinear elliptic equations - Δ u = f(x, u) in all of N with nonlinearities of the form [image omitted] where λ, μ are positive parameters, a(x), h(x) are positive functions, and g(u) is a super-linearly increasing function in a more general fashion than the classical logistic term u2. From a practical point of view, these problems can provide models for fishery or hunting management (cf. [8]) where μ h(x) denotes a harvesting term and, as such, one is interested in situations allowing the existence of positive solutions. From a mathematical point of view, these elliptic problems belong to the class of so-called semi-positone problems (cf. [2]) because the nonlinearity f(x, u) satisfies f(x, 0) < 0. Under suitable assumptions on a(x), h(x), we use variational methods to show that, for each λ > λ1 (a) (where λ1 (a) denotes the principal eigenvalue of - Δ u = λ a(x)u ∈ D1,2(N)), there exists a positive solution decaying at infinity like O(|x|-(N-2)), provided that 0 < μ < [image omitted](λ).
Publisher: Taylor & Francis
Source file: Elektronische Wetenschappelijke Tijdschriften
 
 

                             Details for article 50 of 69 found articles
 
<< previous    next >>
 
 Koninklijke Bibliotheek - National Library of the Netherlands