The effect of random perturbations on near-resonant motions in non-lin
ear oscillatory systems is investigated. It is assumed that the equati
ons of motion of the system can be reduced to standard form with a sma
ll parameter epsilon, and that an isolated primary resonance exists in
the unperturbed system [1]. The behaviour of the perturbed system in
the epsilon-neighbourhood of the resonance surface is considered and a
n effect analogous to deterministic ''capture in resonance'' [1] in an
asymptotically long time interval is investigated. (C) 1998 Elsevier
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