Abstract
The record of any properties of a ship's motion looks very much like the record of wave surface, and for analyzin of them, the same method has been used as in wave analysis. In this paper, the author sought to find the properties of ship's oscillation by TAKAHASHI and FUSHIMI's method, which has been used in the analysis for geophysical problem, as follows ; (1) By means of a periodgram of ship's oscillation, to find the irregularity of it (2) Calculating the properties of ship's oscillation by TAKAHASHI and FUSHIMI's method (3) Analyzing by means of harmonic analysis, to calculate the true period of ship's oscillation (4) On the motion record in Fig.1, the writer got the following results ; 1) True period T_0=6.3 seconds 2) Δφ= λφ^n n=1.67 Δφ: The decrement per swing φ: The mean angle of swing corresponding to the decrement 3) Bertin's coefficient N=0.017
