“On Some Considerations on the Statistical Analysis of Ship Response in Waves”

Abstract

The impulse response function, which had not been used so commonly in ship response, has come to be rather oftenly discussed in these days. This author has written about the usefulness of that function, and made clear the possibility of getting this statistically from the response in rough sea, through correlogram analysis. Here an example of this method is shown and the merit and the demerit of this method is considered.Secondly, the effect of nonlinearity of the response system on the computation of spectrum and the response function is estimated through an approximation method. The character of the truncation of the spectrum by this effect is introduced, and an example in rolling with square damping is shown.As an Appendix, the data processing scheme for the estimation of the frequency response of a ship are summarized from an effort to standardize the statistical analysis of frequency response function of a system.