The envelope process is a useful analytical tool which is often used to study wave groups. Most research on statistical properties of the envelope, and thus of wave groups, was focused on one dimensional records. However for the marine application, an appropriate concept should be two dimensional in space and variable in time. Although a generalization to higher dimensions was introduced by Adl...

In order to simulate or control the coupled heave–pitch motion of ships in waves as realistically possible, an appropriate mathematical model must be established advance. this paper, a nonparametric identification method, based on combination random decrement technique (RDT) and support vector regression (SVR), was proposed by only using measured responses at sea. First, describe irregular wave...