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Study of Rip Current Warning Index Function according to Real-time Observations at Haeundae Beach in 2012

2012년 해운대 해수욕장의 실시간 관측정보에 따른 이안류 경보지수 함수 연구

  • Choi, Junwoo (Korea Institute of Civil Eng. & Building Tech.)
  • 최준우 (한국건설기술연구원 하천해안연구실)
  • Received : 2014.01.10
  • Accepted : 2014.06.17
  • Published : 2014.08.01

Abstract

The rip current warning index function, which estimates the likelihood of dangerous rip current in the real-time rip current warning system operating to help mitigate against rip current accidents at Haeundae beach, was studied. The rip current warning index evaluated as a function of various real-time observations was developed based on Choi et al. (2013b). This study shows a version of rip current warning index improved by including the effect of wave direction and spreadings of frequency-directional spectrum on rip current likelihood. The wave and tidal observations in 2012 at Haeundae coast were applied to the rip current index function, and its performances at several real events found based on CCTV images were presented and analyzed.

이안류 안전사고의 저감을 목적으로 매년 여름 해운대 해수욕장을 대상으로 운영되고 있는 실시간 이안류 경보시스템에서 이안류의 발생정도를 생산하는 이안류 경보지수 함수를 연구하였다. 실시간 관측정보를 입력변수로 하여 이안류 발생정도를 산정하는 이안류 경보지수 함수는 Choi et al. (2013b)의 연구를 기반으로 연구가 진행되었다. 본 연구에서는 입사파의 파향과 스펙트럼의 광협도가 이안류 발생정도에 미치는 영향을 고려하므로 이안류 경보지수 함수를 개선하였다. 2012년에 운영된 해운대 파랑 관측자료와 부산조위소의 조위정보를 개선된 이안류 지수 함수에 적용하였고, CCTV를 통해 확인된 몇 차례의 이안류 발생사건에 대하여 관측결과와 적용한 결과를 비교하여 제시하였다.

Keywords

References

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