R. Grimshaw et N. Joshi, WEAKLY NONLOCAL SOLITARY WAVES IN A SINGULARLY PERTURBED KORTEWEG-DEVRIES EQUATION, SIAM journal on applied mathematics, 55(1), 1995, pp. 124-135
A fifth-order Korteweg-de Vries equation is considered, where the fift
h-order derivative term is multiplied by a small parameter. It is know
n that solitary wave solutions of this model equation are nonlocal in
that the central core of the wave is accompanied by copropagating trai
ling oscillations. Here, using the techniques of exponential asymptoti
cs, these solutions are reexamined and it is established that they for
m a one-parameter family characterized by the phase shift of the trail
ing oscillations. Explicit asymptotic formula relating the oscillation
amplitude to the phase shift are obtained.