Journal of Korean Society of Coastal and Ocean Engineers (한국해안·해양공학회논문집)

Korean Society of Coastal and Ocean Engineers (한국해안·해양공학회)
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Optimal Estimation of the Peak Wave Period using Smoothing Method

평활화 기법을 이용한 파랑 첨두주기 최적 추정

  • Uk-Jae, Lee (Coastal Development and Ocean Energy Research Center, Korea Institute of Ocean Science & Technology) ;
  • Byeong Wook, Lee (Rural Research Institute, Korea Rural Community Corporation) ;
  • Dong-Hui, Ko (Coastal Development and Ocean Energy Research Center, Korea Institute of Ocean Science & Technology) ;
  • Hong-Yeon, Cho ( Marine Big-data Center, Korea Institute of Ocean Science and Technology)
  • 이욱재 (한국해양과학기술원 연안개발에너지연구센터) ;
  • 이병욱 (한국농어촌공사 농어촌연구원) ;
  • 고동휘 (한국해양과학기술원 연안개발에너지연구센터) ;
  • 조홍연 (한국해양과학기술원 해양빅데이터센터)
  • Received : 2022.11.01
  • Accepted : 2022.12.12
  • Published : 2022.12.31
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Abstract

In this study, a smoothing method was applied to improve the accuracy of peak wave period estimation using the water surface elevation observed from the Oceanographic and Meteorological Observation Tower located on the west coast of the Korean Peninsula. Validation of the application of the smoothing method was per- formed using variance of the surface elevation and total amount wave energy, and then the effect on the application of smoothing was analyzed. As a result of the analysis, the correlation coefficient between variance of the surface elevation and total amount wave energy was 0.9994, confirming that there was no problem in applying the method. Thereafter, as a result of reviewing the effect of smoothing, it was found to be reduced by about 4 times compared to the confidence interval of the existing estimated spectrum, confirming that the accuracy of the estimated peak wave period was improved. It was found that there was a statistically significant difference in proba- bility density between 4 and 6 seconds due to the smoothing application. In addition, for optimal smoothing, the appropriate number of smoothings according to the significant wave height range was calculated using a statistical technique, and the number of smoothings was found to increase due to the unstable spectral shape as the significant wave height decreased.

본 연구에서는 한반도 서해안에 위치한 해상기상관측타워에서 관측된 수면변동자료를 이용하여 첨두주기 산정의 정확도 향상을 위한 평활화 기법을 적용하였다. 평활화 기법 적용에 대한 검증은 파형의 분산값과 관측 자료의 에너지 총량을 통해 수행하였으며, 이후 평활화 적용에 대한 영향을 분석하였다. 분석결과, 파형의 분산값과 관측 자료의 에너지 총량의 상관계수는 0.9994로 나타났으며, 해당 기법 적용에 문제가 없음을 확인하였다. 이후, 평활화 영향 검토를 수행한 결과, 기존 추정 스펙트럼의 신뢰구간에 비해 최대 26% 감소하는 것으로 나타남으로서, 추정되는 첨두주기의 정확도가 향상됨을 확인하였다. 평활화 적용으로 인하여 4~6초 사이에서 확률밀도는 통계적으로 유의미한 차이가 발생하는 것으로 나타났다. 또한, 최적 평활화를 위해 통계적 기법을 이용하여 유의파고 범위에 따른 적정 평활화 개수를 산정하였으며, 평활화 개수는 유의파고가 작아짐에 따라 불안정한 스펙트럼 형상에 의해 증가하는 것으로 나타났다.

Keywords

Acknowledgement

본 연구는 산업통상자원부의 신재생에너지핵심기술개발 사업인 "해상풍력 전주기 HSE 운영지원 모델 개발(과제번호: PN90970)"의 일환으로 수행되었습니다. 연구지원에 감사드립니다.

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