파랑자료의 sampling rate가 극한파의 통계에 미치는 영향

Abstract

Abstract − In this paper time series wave data are simulated using wave spectrum with random phases of thewave signal. The simulated wave signals are used to study the effect of the sampling rate on the ocean wavecharacteristics. Effect of sampling rate on wave data which include extreme wave such as freak waves areexamined and various wave characteristics including abnormality index (AI), kurtosis of wave profile and maxi-mum wave height are examined. Various wave heights are decreased as the sampling rate decreases. The zero-thmoment of the wave spectrum does not affect much on the sampling rate but the second moment are greatelyaffected on the sampling rate. The error due to the sampling rate is decreases as the wave period increases. Theerror in significant wave height based on the wave spectrum H s is smaller than that on the time domain methodH 1/3 . AI index and kurtosis of wave profile do not deviate much from the exact date as long as the sampling rateis greater than 1 Hz. Ocean wave measurement with the sampling frequency higher than 1 Hz will result theerror less than 5% in estimating the height of extreme waves.Keywords: Ocean Wave statistics(해양파 통계특성), Sampling rate(샘플링 레이트), Extreme wave height(극한파고), Freak wave(이상파랑)