Study on Short-term Variability of Ship Responses in Waves

Toshio Iseki, Ulrik Dam Nielsen

Research output: Chapter in Book/Report/Conference proceedingArticle in proceedingsResearchpeer-review

257 Downloads (Pure)


Short-term variability of ship responses is investigated from the view point of cross-spectrum analysis. In a steady state condition, it is well known that a certain length of sampled data are required for stable spectral analysis. However, the phase angle of the cross-spectra has not been discussed in detail. Using long stationary time histories, the transition of amplitudes and relative phase angles of the cross-spectra have been investigated by iterative analyzes with a few seconds of time shifting. In the results, the short-term variability of the relative phase angle was observed. This concludes that the variability influences the accuracy of the wave buoy analogy.
Original languageEnglish
Title of host publicationProceedings of the 131st Conference of Japan Institute of Navigation
Number of pages4
PublisherJapan Institute of Navigation
Publication date2014
Publication statusPublished - 2014
Event131st Conference of Japan Institute of Navigation - Hakodate, Japan
Duration: 1 Oct 2014 → …
Conference number: 131


Conference131st Conference of Japan Institute of Navigation
Period01/10/2014 → …


  • Ship handling and propulsion
  • Wave buoy analogy
  • Aleatory uncertainty
  • Fourier transform
  • Relative phase


Dive into the research topics of 'Study on Short-term Variability of Ship Responses in Waves'. Together they form a unique fingerprint.

Cite this