• 한국지구과학회지
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• 제25권4호
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• pp.277-288
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• 2004

서해 상에서 저기압과 태풍 통과 시 해상상태를 비교 분석을 하였다. 1999년 4월 9일${\sim}$12일에 강한 저기압이 화중지방에서 발생하여 서해를 지나 한반도에 영향을 미친 경우의 9905호 태풍 NEIL과 9907호 태풍 OLGA가 서해를 통과하면서 서해 연안에 영향을 미친 사례이다. 봄철 이동성 저기압 발생 시 에는 저기압 중심부의 풍속이 주변 지역에 비해 위상이 빠르고 강하게 나타나며, 이에 수반되어 발생하는 파고는 주변의 지형적 영향으로 다르게 나타날 수 있다. 이에 비해 두 태풍에 의해 발생한 파고는 태풍 Olga가 서해 남부해역에서 북상할 시기에 칠발도 근해상에서 5m이상의 높은 유의파고를 발생한 것 이외에는 저기압 통과 시보다 파고가 낮다. 해일도 태풍보다 저기압 통과 시에 더 크게 나타나는데, 이러한 결과는 강하지만 국지적이고 빠르게 이동하는 태풍보다 종관적이고 느리게 이동하는 기압장에 의해 발생한 파도와 해일이 더 클 수 있음을 보여준다.

• 융합신호처리학회논문지
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• 제22권4호
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• pp.164-170
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• 2021

해상 풍력발전기의 운동 성능 분석 및 개선을 위한 연구가 수행되었다. 본 연구에 사용된 형상은 과거 연구를 참고하여 가져온 것이며 이를 바탕으로 수선면적의 크기를 80% 60% 40% 20%로 각각 설계하여 이에 따른 운동성능을 확인해 보았다. 해상상태는 Sea State 4, 5, 6에서 계산을 수행하였다. 계산과정에서는 상업용 전산 유체역학(ANSYS)과 AQUA를 사용하여 계산을 수행하였다. 전반적인 운동성능의 경우 이론과 동일하게 수선면적의 크기가 줄어들수록 HEAVE, ROll, PITCH와 같은 운동이 줄어드는 것을 확인할 수 있었다. 하지만 수선면적의 크기가 급격히 줄어든 형상의 경우 복원성 계산을 진행하였을 때 복원성능에서 만족하지 못하는 경우가 발생할 수도 있다는 것을 확인할 수 있었다. 또한 해상상태에 따른 적정의 수선면이 있을 수도 있다는 것을 확인할 수 있었다.

• Strategy21
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• 통권41호
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• pp.153-173
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• 2017

On 15 December 2015, China seized an underwater drone belonging to the U.S. in the South China Sea. The underwater drone was then about to be retrieved by the Bowditch, a U.S. naval ship.Although China returned the underwater drone to the U.S. on 20 December 2016, the incident resulted in the considerable controversy involving the use of underwater drones. The reason for this is that the seizure of the underwater drone happened in the exclusive economic zone (hereafter referred to as "EEZ") of the Philippines. Part XIII of the United Nations Convention on the Law of the Sea (hereafter referred to as "UNCLOS") governs the matters of marine scientific research (hereafter referred to as "MSR"). If a State intends to use an underwater drone in the EEZ of another coastal State for the purpose of MSR, the former has to obtain the consent of the latter in accordance with relevant provisions included in Part XIII of the UNCLOS. However, it is not obvious whether the consent of a coastal State should be required to launch an underwater drone in the EEZ of the State for the purpose of hydrographic surveying or military surveying. Maritime powers such as the U.S. regard hydrographic surveying or military surveying as part of "other internationally lawful uses of the sea related to these freedoms, such as those associated with the operation of ships, aircraft and submarine cables and pipelines" found in Article 58(1) of the UNCLOS, or part of the freedom of the high seas. This interpretation is not incompatible with the implications that the UNCLOS has. Nevertheless, Korea cannot accept this kind of interpretation that is supported by maritime powers. The freedom of hydrographic surveying or military surveying could imply that the EEZ of Korea would be full of underwater drones launched by China, Japan or even Russia. Hence, Korea should claim that the data collected for the purpose of MSR cannot be distinguished from that collected for the purpose of hydrographic surveying or military surveying. This means that hydrographic surveying or military surveying without the consent of a coastal State in the EEZ of the State should not be permitted.

• 한국해양학회지:바다
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• 제24권3호
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• pp.389-399
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• 2019

동해 울릉분지의 탄산칼슘 포화상태를 1999, 2014, 2017, 2018년도 해양 조사를 통해 수집된 pH, 용존무기탄소(DIC), 총알칼리도(TA) 자료를 이용하여 계산하였다. 1999년에 비해 2010년대에 전 수심에서 탄산염 포화상태는 유의하게 감소하였다. 2018년 현재 방해석과 선석의 포화면 수심은 각각 약 500 m와 200 m로 상승하였다. 탄산칼슘 포화상태를 결정하는 주된 화학종인 탄산이온은 상층과 심층에서 다른 분포를 보였다: 상층에서는 약 $175{\mu}mol\;kg^{-1}$로 비교적 높고, 심층에서는 $50{\mu}mol\;kg^{-1}$ 이하로 아주 낮게 나타났다. 그러나 탄산이온 농도의 감소 경향은 심층보다 상층에서 두드러졌는데, 이는 2000년대에 대기에서 이산화탄소의 침투가 주로 상층에서 일어나는 것이 반영된 결과로 해석된다.

• 한국해양공학회지
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• 제19권3호
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• pp.47-53
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• 2005

Model for dust and salt transportation from the dried bottom of the Aral Sea is suggested. Theoretical analysis is based on the turbulent diffusion equation for the averaged function of passive impurity concentration. One-layer model of the atmospheric boundary layer is assumed. Impurity precipitation rates are calculated as the functions of the particle size and the distance source of particles. Analytical solutions for the point and two-dimensional sources of impurities are found. Model calculations for salt and sand transport from the Aral Sea basin are made on the basis of 2D source model with a constant intensity.

• 한국수산과학회지
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• 제47권2호
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• pp.168-173
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• 2014

The effect of critical minimum depth in the coastal region on storm surges was examined using a three-dimensional primitive equation model (POM). Case studies using numerical experiments in a small coastal bay in the southern sea of Korea (Hanam Bay) have examined the 'critical depth' (CD) that stabilizes the numerical calculations. Dependence of the CD of typhoon tracks and tidal components such as M2, S2, O1, and K1 were examined. The model results clearly demonstrated that the numerically unstable state of the calculation was caused by the coarse resolution of sea surface elevation.

• 수산해양교육연구
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• 제26권1호
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• pp.126-133
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• 2014

For boarding comfort and pleasant boarding sensitivity of passenger in passenger ship, there are a few methods such as motion sickness rate or MSI(Motion Sickness Incidence) to assess safety of passenger ship. To find out MSI or motion sickness rate of the training vessel Kaya of Pukyong National University, we use lots of various factors: sea condition, incident angle in main sail way, economic speed, calculation position of motion sickness, sea state, work place and reduce zone of ship. In this paper, we adopted Maxsurf Seakeeper program based on Strip Theory and carefully compared theoretical results with experimental results.

• 해양환경안전학회지
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• 제2권1호
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• pp.143-143
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• 1996

Recent Class requirements and IMO recommendations concerning Hull Strength Monitoring (HSM) have prompted an increasing number of shipowner to adopt monitoring systems on bulk carriers and tanker. Such systems are designed to give warning when stress levels and the frequency and magnitude of ship motions approach levels which require corrective action. When fitted these systems provide enhanced operational safety and efficiency. This paper describes a development beyond the standard BMT HSM system through the integration of stress, motion and radar-based sea state monitoring with powerful, on-board, artificial intelligence (AI) tools. The latter utilises conceptual clustering techniques as an aid to pattern recognition in stress, fatigue. motion and sea state data clusters. This, in turn, provides additional operational guidance for ship's staff. Feedback from applications of the standard BMT HSM and extended HSM systems on board the British Steel Bulk Shipping fleet is described.