共振条件下具有奇异性和无界扰动Duffing方程的周期解

In this paper, we study the existence of periodic solutions of Duffing equations with singularities where is a positive integer and is locally Lipschitz continuous and has a singularity at the origin. By using phase plane analysis method and the continuation theorem, we prove that the given equation has at least one periodic solution provided that is unbounded and satisfies sub-quadratic condition at infinity.