Abstract:
The existence of solutions for the Dirichlet problem associated to
bounded perturbations of positively-(p, q)-homogeneous Hamiltonian sys tems is considered both in nonresonant and resonant situations. In order
to deal with the resonant case, the existence of a couple of lower and up per solutions is assumed. Both the well-ordered and the non-well-ordered
cases are analysed. The proof is based on phase-plane analysis and topo logical degree theory