Kinks in the parametrically excited sine-Gordon equation and method of   averaging
  Parametrically excited sine-Gordon equation is considered. Excitation is a fast oscillating periodic function with zero mean. Technique of classical method of averaging enables to construct the averaged equations in a variety of assumptions about driving amplitude. The averaged equation possesses kinks solutions. The results can be applied to the study of movement of Bloch walls for ferromagnetic crystals in the presence of a rapidly oscillating magnetic field and to describe the fluxon dynamics in long Josephson junctions. 
Vladimir Burd
math.CA