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Boundary Value Problems
Boundary Value Problems Cover Image
  • Research Article
  • Open Access

Quasi-concavity for semilinear elliptic equations with non-monotone and anisotropic nonlinearities

Boundary Value Problems20062006:80347

https://doi.org/10.1155/BVP/2006/80347

©  Antonio Greco 2006

  • Received: 24 August 2004
  • Accepted: 9 August 2005
  • Published:

Abstract

A boundary-value problem for a semilinear elliptic equation in a convex ring is considered. Under suitable structural conditions, any classical solution lying between its (constant) boundary values is shown to decrease along each ray starting from the origin, and to have convex level surfaces.

Keywords

  • Differential Equation
  • Partial Differential Equation
  • Ordinary Differential Equation
  • Functional Equation
  • Structural Condition

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Authors’ Affiliations

(1)
Dipartimento di Matematica e Informatica, via Ospedale 72, Cagliari, 09124, Italy

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Copyright

© Antonio Greco 2006

This article is published under license to BioMed Central Ltd. This is an open access 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.

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