• Proceedings of the Korea Water Resources Association Conference
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• 2018.05a
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• pp.71-71
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• 2018

Sea pollution accidents have been occurred due to the increase of marine ship traffic. Oil spill from the hull hole induced by tanker collision results in the huge sea pollution. Proper and prompt reaction on such oil spill disaster is needed to minimize the damage. Thru-hull emergency wood plug is typically used to manually close small holes, while it is required to develop some mechanical devices for closing large holes in the hull due to huge fluid pressure. Accurate estimation of oil discharge and velocity from such holes are important to develop proper device to control hull hole damage. High resolution CFD modeling investigation on the configurations of hull hole of 7.5 m initial depth and 30 cm diameter, which was observed in the oil spill accident of the Hebei Sprit off the west coast of Korea in 2007, has been carried out to compute the oil spill velocity distribution in terms of flow depth. Friction loss due to the viscous flow and the discharge coefficient of crude oil with specific gravity SG = 0.85 and viscosity of $4-12cP(mPa{\cdot}s)$ at the temperature of $20^{\circ}C-100^{\circ}C$ are presented in terms of Reynolds number based on the results of high-resolution CFD modeling.

• Journal of the Korean Society for Marine Environment & Energy
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• v.4 no.4
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• pp.21-31
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• 2001

When an oil-spilling accident occurs at sea, it is of the primary importance to predict the amount of oil leakage for the swift response and decision-making. The simplest method of oil-leakage estimation is based on the hydrostatic pressure balance between oil inside the tank and seawater outside of leakage hole, that is the so-called Torricelli equilibrium relation. However, there exists discrepancy between the reality and the Torricelli relation, since the latter is obtained from the quasi-steady treatment of Bernoulli equation ignoring viscous friction. A preliminary experiment has been performed to find out the oil-leaking speed and shape. Soy-bean oil inside the inner tank was ejected into water of the outer tank through four different leakage holes to record the amount of oil leakage. Furthermore, a CFD (Computational Fluid Dynamics) method was utilized to simulate the experimental situation. The Wavier-Stokes equations were solved for two-density flow of oil and water. VOF method was employed to capture the shape of their interface. It is found that the oil-leaking speed varies due to the frictional resistance of the leakage hole passage dependent on its aspect ratio. The Torricelli factor relating the speed predicted by using the hydrostatic balance and the real leakage speed is assessed. For the present experimental setup, Torricelli factors were in the range of 35%~55% depending on the aspect ratio of leakage holes. On the other hand, CFD results predicted that Torricelli factor could be 52% regardless of the aspect ratio of the leakage holes, when the frictional resistance of leakage hole passage was neglected.

• Journal of the Korean Society for Marine Environment & Energy
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• v.5 no.4
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• pp.63-73
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• 2002

This paper presents the results of a ten-day long survey for assessing the possibility of further oil spillage from the sunken tanker, Kyung-Shin(995 G/T), which had sunken in the East Sea, off Pohang City, in February 1988. The survey was conducted using remotely operated vehicle(ROV), manned submersible and ultrasonic thickness gauge in September 2001. The external inspection by the optical camera shows that small scale oil spill has been continued from the sunken ship. It's hull thickness was also measured at several points of the ship, using an ultrasonic sensor for assessing the current corrosion status of the sunken ship. Taking into account the results of this survey and the existing salvage report, it is estimated that the remaining oil in the tanker is approximately 600 ㎘, and this oil could be leaked into marine environment due to continuous severe corrosion if no preventive is taken.

• Journal of the Society of Naval Architects of Korea
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• v.37 no.2
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• pp.100-108
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• 2000

As U.S. congress and I.M.O. have recently adopted strengthened MARPOL73/78 regulations on marine pollution, it is necessary to develope a new type of tankers such as Double hull tanker(D/H Tanker) and Mid-deck tanker(M/D Tanker) and so on. Because most of researches are concentrated on the volume of oil spill due to collision of ships, in this paper, a structural design program for D/H Tankers and M/D Tankers is developed to suggest the effective type of tankers by comparing structural characteristics between their types. By this program, minimum hull weight designs of D/H tankers and M/D tankers considering tank arrangement are performed and the design results are compared each other. The efficient types of hull structure for the minimum weight design between D/H tankers and M/D tankers is proposed.

• Bulletin of the Society of Naval Architects of Korea
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• v.30 no.2
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• pp.31-43
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• 1993

본 연구에서는 힁부재가 없는 AFRAMAX급 신구조 방식의 유조선을 개발하고자 하였다. 설계의 기본 개념은 1) 이중선체구조를 채용하여 해난사고 발생시 기름유출 방지를 피하고, 2) 힁부재가 없는 극히 단순한 선체구조를 채용하여 용접 로봇등을 활용한 자동건조 비율을 높임으로써 건조 생산성을 향상시키는데 주안점을 두고 있다. 설계 결과 얻어진 선체구조는 기존의 유조선 구 조와 매우 상이하다. 초기구조설계단계에서 구조 부재의 치수는 기존의 선급설계 지침을 활용 하여 결정하였으나, 기존의 유조선 구조와 비교하여 구조배치가 크게 바뀌어 졌기 때문에 기존의 선급설계지침을 만족했다고 해서 구성부재와 국부구조뿐만 아니라 구조 전체적으로도 충분한 구조안전성을 가지고 있는지는 확실치 않다. 따라서 직접구조해석에 의한 구조안전성 평가가 필수적으로 요구되며, 이를 위해 저자들은 선체구조의 최종 종강도(ultimate longitudinal strength), 최종 힁강도(ultimate transverse strength) 및 최종 국부강도(ultimate local strength )를 기준으로한 구조안전성 평가를 수행하였다. 본 논문에서는 이들 중에서 국부 구조부재에 대한 안전성평가 문제만을 다루었다. 결론적으로, 본 연구에서 개발한 선체구조는 건전상태(intact condition)하에서 뿐만 아니라 손상상태하에서도 구조부재는 좌굴 또는 붕괴하지 않고 전반적 으로 충분한 구조안전성을 가지고 있다는 결론을 내릴 수 있었다.

• Proceedings of KOSOMES biannual meeting
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• 2008.05a
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• pp.205-211
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• 2008

Those days, not only many peoples are killed and the wounded by effective of disaster sea wave in Indonesia, but also our country effected by disaster in adjoining sea to japan. At this point, preparation to disaster and the point of quickly communication by happened disaster. For this reason perceptible observation post are making so quickly communication system to zone by effective range of disaster, acd develope than more quality observation tool, contribute to keep citizens property acd life to a minimum by disaster damaged.

• Journal of the Korean Society for Marine Environment & Energy
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• v.12 no.4
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• pp.279-283
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• 2009

Approximately 12,547 kL of oil from the tanker 'Hebei Spirit' released into the western sea of Korea, which subsequently reached and covered extensive areas of the western coastlines of Korea. In the following days great numbers of tar balls hit the southwestern coast. Three different cleanup methods were used to mediate the southwestern coastline tar ball pollution by Korea Coast Guard (KCG) net setting, manual pick up, and sweeping them up. Net setting was useful in protecting coastlines from being hit by tar balls. The cold weather in winter conditions helped the tar ball response efforts because it caused them to harden, allowing them to be swept up from beaches and to be gathered up by hand.

• Journal of the Korean Society for Marine Environment & Energy
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• v.6 no.4
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• pp.3-12
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• 2003

Due to the high demand on energy resources accompanied by continuing industrialization and urbanization, the world marine transportation of crude and product oils is being gradually increased. In Korea, we are exposed to the large-scale marine oil spill accidents because a very large oil tanker of 300,000 tonnage must enter Korean Ports every day to meet the domestic demand on oils. Although we are exerting our strength to reduce the probability of marine oil pollution accidents, a unrestorable oil spill is to occur owing to human errors, severe weather conditions, or combined causes. Thus, area contingency plan equipped with appropriate management system for response and restoration for the worst case discharge scenario must be entirely prepared to protect mine environments and coastal resources. In particular, we are focusing on the Environmental Sensitivity Index Map(ESI Map) to reduce the environmental consequences of both spills and clean-up efforts by specifying protection Priorities in advance and identifying in-situ response strategies. In this paper, Korean ESI Map is introduced with brief definition of sensitivity to oiling and main features of the software developed hitherto.

• Journal of Navigation and Port Research
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• v.26 no.3
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• pp.261-268
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• 2002

At recently, Oil spill accident of large size oiler that happen domestic and outside the country is occured to social impact us as well as economical damage in sea environment. Also, because spread extent of pollution accident is reaching harbor, bay and close water areas, as necessity that traffic control ships are sea place. VTS is changing to concept that control space is magnified gradually. Our country is operated to 14 harbors which is control center. But abroad is operating coastal VTS that do main waterway and coastals to authority dimension. Therefore, necessity that traffic density of ship manages high coastals and ship traffic of waterway to our country is risen. This paper is execute sea traffic survey at Mokop sea areas and sea casualty occurs. It proposal that coastal VTS center field of most suitable and position of radar site.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2011.11a
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• pp.154-155
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• 2011

2010년 천리안위성의 성공적인 발사에 따라 인공위성의 활용에 대한 기대가 커지고 있다. 천리안 해양관측위성(GOCI)이외에 아리랑 2호가 현재 운용중인 우리나라 위성들이다. 가까운 시기에 아리랑 5호(2011년 말), 아리랑 3호(2012년), 아리랑 3A호(2013년)가 발사될 예정이다. 즉, 해양적용을 위한 위성환경은 이제부터 준비되고 있다고 볼 수 있다. 대외적으로 보면, 인공위성 자원은 아주 많다. 문제는 이와 같은 자원을 어떻게 활용할 것인가 인데 이의 활용 기술 개발적 측면에서는 많이 소홀한 것이 사실이다. 전세계적으로 이 시스템 개발을 위한 치열한 경쟁이 진행 중에 있다. 이미 소말리아 주변 감시체계는 많은 부분을 위성에 의지하고 있다. 우리나라에서 최초로 위성활용 가능성을 보여준 사건이 허베이스피리트호 원유유출 사고이다. 이 사고는 2007년 12월7일 아침 7시6분경 서해안 만리포 북서쪽 10km 해상에서 크레인을 적재한 1만1800t급 바지선이 정박 중인 홍콩 선적 유조선 허베이 스피리트호(14만6000t급)와 부딪치면서 발생했다. 이와 같은 기름 유출 사고의 경우, 유출 범위를 정확하게 이해하는 것이 중요하다. 거의 준비된 상태가 아님에도 불구하고 12월 8일 아침 최초로 유출된 기름을 모습을 보여주는 위성이미지(광학위성)가 얻어졌다. 하지만 이와 같은 자료가 관련 전문가가 이용할 수 있기까지 많은 시간이 소용되었고, 이 정보를 전달할 수 있는 방법도 없었다. 사실 단순한 이미지가 아니라 지리정보체계를 가진 오염정보를 제공할 방법도 준비도 되어 있지 못한 상황이었다. 본 발표를 통하여, 허베이스피리트호 사고뿐만 아니라, 2011년 6월부터 수개월간 지속된 발해만 오염사고 적용 등 다양한 사례 소개를 하고, 이를 기반으로 해양경찰청에서 업무활용을 위한 방안을 제시한다. 먼저, 해경청의 주요 임무인, 경비, 수색구조, 오염대응 분야별로 현황 분석을 수행하였다. 또한 국외사례에 대한 조사를 한 후, 최종 인공위성 원격탐사기술의 해경청 도입방안에 대한 설계를 실시하였다. 국제적으로 인공위성을 이용한 해양 경비, 수색구조, 오염 모니터링기술 개발이 이루어지고 있으며, 유럽 국가는 시범도입을 진행 중에 있다. 유럽해사안전국(EMSA)은 해양경비 및 수색구조를 위한 선박통항 및 보고 서비스와 오염대비대응(Pollution Preparedness and Response, PPR) 위성 서비스를 회원국에 제공하고 있다. 해양경찰청 임무 수행뿐만 아니라, 해양영토 관리적 측면에서 첨단 위성장비 활용, 선진국형 해상경비 패러다임의 전환 필요성이 크다고 할 수 있다.