Positive solutions of singular Dirichlet and periodic boundary value problems

Positive and dead core solutions of singular Dirichlet boundary value problems with phi-Laplacian

The paper discusses the existence of positive solutions, dead core solutions and pseudodead core solutions of the singular Dirichlet boundary value problem (φ(u)) = λ[ f (t, u, u) + h(t, u, u)], u(0) = u(T ) = A. Here λ is the positive parameter, A > 0, f is singular at the value 0 of its first phase variable and h may be singular at the value 0 of its second phase variable. c © 2007 Elsevier L...

Positive Solutions for a Class of Singular Boundary-value Problems

This paper concerns the existence and multiplicity of positive solutions for Sturm-Liouville boundary-value problems. We use fixed point theorems and the sub-super solutions method to two solutions to the problem studied. Introduction Consider the boundary-value problem Lu = λf(t, u), 0 < t < 1 αu(0)− βu′(0) = 0, γu(1) + δu′(1) = 0, (0.1) where Lu = −(ru′)′ + qu, r, q ∈ C[0, 1] with r > 0, q ≥ ...

Positive Solutions of Singular Complementary Lidstone Boundary Value Problems

Positive Solutions for a Class of Singular Boundary-value Problems

Using regularization and the sub-super solutions method, this note shows the existence of positive solutions for singular differential equation subject to four-point boundary conditions.

Positive Symmetric Solutions of Singular Semipositone Boundary Value Problems

Using the method of upper and lower solutions, we prove that the singular boundary value problem, −u = f(u) u in (0, 1), u(0) = 0 = u(1) , has a positive solution when 0 < α < 1 and f : R → R is an appropriate nonlinearity that is bounded below; in particular, we allow f to satisfy the semipositone condition f(0) < 0. The main difficulty of this approach is obtaining a positive subsolution, whi...