In this work, the response of a ship rolling in regular beam waves is studied.The model is one degree of freedom model for nonlinear ship dynamics.The model consists of the terms 92-95 civic k-swap mounts containing inertia, damping, restoring forces, and external forces.The asymptotic perturbation method is used to study the primary dl0211 resonance phenomena.
The effects of various parameters are studied on the stability of steady states.It is shown that the variation of bifurcation parameters affects the bending of the bifurcation curve.The slope stability theorems are also presented.