数学物理学报(英文版) ›› 1994, Vol. 14 ›› Issue (S1): 40-45.

• 论文 • 上一篇    下一篇

EXISTENCE OF POSITIVE SOLUTION TO-Δu=f(x,u) WHEN f CHANGES SIGNS

姜明   

  1. Dept. Appl. Math, Beijing Institute of Technology, Beijing 100081, China
  • 收稿日期:1992-03-06 出版日期:1994-12-31 发布日期:1994-12-31
  • 基金资助:
    Research supported by a Youth Grant from National Natural Science Foundation of China.

EXISTENCE OF POSITIVE SOLUTION TO-Δu=f(x,u) WHEN f CHANGES SIGNS

Jiang Ming   

  1. Dept. Appl. Math, Beijing Institute of Technology, Beijing 100081, China
  • Received:1992-03-06 Online:1994-12-31 Published:1994-12-31
  • Supported by:
    Research supported by a Youth Grant from National Natural Science Foundation of China.

摘要: The existence of positive solutions to the semlinear elliptic boundary value problem
-Δ=f(x,u) in Ω and u=0 on ∂Ω is studied in this paper. The result obtained differs from the other known results in that the positivity of the solution does not follow from the positivity of f.Our result roughly says that if Ω is not too wide in some one direction, there is always a positive solution even if f changes signs, which is proved using the so-calles sub-super solution approach.

关键词: Positive solution, Semliinear elliptic boundary valed problem

Abstract: The existence of positive solutions to the semlinear elliptic boundary value problem
-Δ=f(x,u) in Ω and u=0 on ∂Ω is studied in this paper. The result obtained differs from the other known results in that the positivity of the solution does not follow from the positivity of f.Our result roughly says that if Ω is not too wide in some one direction, there is always a positive solution even if f changes signs, which is proved using the so-calles sub-super solution approach.

Key words: Positive solution, Semliinear elliptic boundary valed problem