대한민국의
발전과 안전은
바다에서도
멈추지 않습니다
대한민국 해양과학기지는 바다 위의 안전 그리고
대한민국 대륙의 발전을 수호합니다
연구성과
해양과학기지의 연구성과
해양과학기지의
연구는
바다, 하늘 그리고
대륙을 가리지
않습니다
연구성과 전체 보기
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In order to study oceanic environmental changes affecting the climate change and global warming, the Korean government supports the construction and operation of several ocean research stations (ORS) such as Ieodo ORS, Gageocho ORS and Sochengcho ORS in remote area. Among these ORSs, the Gageocho ORS was directly attacked by Typhoon Muifa in 2011 and its structural members were severely damaged. After this structural failure, the Gageocho ORS was rehabilitated and instrumented with dynamic measurement system. In this study, the preliminary finite element (FE) model of the repaired Gageocho ORS was updated using the natural frequencies estimated by the measurement. Mass reallocation method and the pattern search method were utilized for the FE model updating. The former was applied to rationally redistribute the lumped mass ignored in static analysis in platform and the latter was used to obtain the optimal values for mass redistribution as well as other material properties such as an elastic modulus of concrete. This significantly reduced the errors of natural frequencies for the estimated values by under 1% from larger than 15% in the preliminary FE model. The updated baseline FE model can be useful for further performance analysis including reliability analysis, wave and seismic analysis, and also for structural health monitoring.
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This study aims at characterizing the distinctive features of a spatio-temporal nonlinear wave surface. We analyze wind-generated 3-D wave fields observed during the passage of an atmospheric front, which led to a wide directional spreading of wave energy. Data were acquired from the ocean research station Socheongcho-ORS (Yellow Sea) with a stereo wave imaging system. They include 3-D (i.e. 2-D + time) measurements of the sea surface elevation with high spatial and temporal resolution over a swath larger than any previous similar deployment. We examine the shape and the nonlinear properties of the wavenumber/frequency 3-D wave spectrum, and the characteristic spatial, temporal and spatio-temporal length scales of the wave field. We then focus on analyzing the probability of occurrence and the spatio-temporal size of the rogue waves we identified in the data. In particular, we provide for the first time an empirical estimate of the extent of the horizontal sea surface spanned by rogue waves. We also propose and assess a novel strategy to determine from the 3-D wave spectrum the vertical current profile, to be then used to map the spectrum on intrinsic frequencies.
미디어
해양과학기지의 사진과 비디오
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옹진소청초 해양과학기지
옹진소청초 해양과학기지
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신안가거초 해양과학기지
신안가거초 해양과학기지
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이어도 해양과학기지
이어도 해양과학기지