A new kind of integral transform and its application to periodic solutions (Q1105805)

The author makes an interesting study on a new integral transform and proves several theorems concerning the properties of the transform. He also proves some general existence theorems for periodic solutions of the semilinear wave equation with the forcing term having double frequency. The present method is then applied to solve almost periodic solution for nonlinear wave equation, and to semilinear autonomous wave equation. This long article contains many new and interesting results which seem to have useful applications.