• Proceedings of the Korean Information Science Society Conference
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• 2004.04a
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• pp.904-906
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• 2004

효율적인 예망훈련을 위해서는 사실성에 근거한 어군분포와 어선운항 시뮬레이터의 개발이 절실하다. 그러나 수중이라는 다변적인 환경요인이 현장 계측을 어렵게 하거나 어류의 분포가 비선형적인 양상을 보이기 때문에 단순한 그래픽처리는 실제 예망훈련을 위한 어군분포에 따른 탐지에 제한성를 갖게 된다. 이에 본 논문에서는 사실성에 근거하면서도 비선형적인 특성을 부과한 어군분포모델을 제안하여 효과적인 어탐 시뮬레이터가 이루어지도록 구현하였다. 아울러, 어탐 시뮬레이터와 연동하여 어선운항 시뮬레이터를 제공함으로서 실제 어로작업 환경과 유사하도록 구현하였다. 또한, 제안된 시뮬레이터는 현재 사용되고 있는 어선의 운항 브리지와 통계학적 근거에 따른 데이터베이스의 사용으로 훈련효과를 극대화할 수 있다.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2003.05a
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• pp.742-748
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• 2003

As for marine propulsion shafting system using 4 stroke diesel engine, it is common to apply reduction gear box between diesel engine and shafting with a view of increasing mechanical efficiency, which inevitably require elastic coupling due to avoid chattering and hammering inside of gear box. In this study, optimum method of rectifying propulsion shafting system in case of 750ton fishing vessel specially in a view of torsional vibration, is theoretically studied. After exchange of diesel engine and gear box, analysis result of torsional vibration get worse and so some countermeasure are needed. The elastic coupling is modified from present block type rubber coupling showing relatively high torsional stiffness to rubber coupling with two series elements directly connected. The vibration measurement using two laser torsion meters was done during sea trial, whose results are compared to those of calculation and verified.

• Journal of Korea Ship Safrty Technology Authority
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• s.24
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• pp.38-56
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• 2008

우리나라의 경우 해양사고에서 어선이 차지하는 비율은 매우 높아 최근 5개년 동안 전체 해양사고 중 어선사고 비율이 약 68%를 점유하고 있어 해양사고 비율이 가장 높은 어선사고로 부터 인명손실을 예방하기 위한 실용적이고 효과적인 대책이 시급한 실정이다. 본 연구는 어선사고 중 다른 사고에 비해 막대한 인명피해나 재산상의 손실을 초래하는 어선사고 유형인 전복.침몰.화재와 최근에 많이 발생하고 있는 낚시어선사고와 어업재해사고를 중점 대상으로 사례조사를 통하여 자율적인 어선 인명사고 예방체제 수립 및 어업종사자와 안전의식 고취를 제고하고자 한다.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.2
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• pp.335-338
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• 2006

This report introduces a National Vessel Monitoring System(NVMS) within the General Information Center On Maritime Safety and Security(GICOMS) project and a national legislation system for ship's safety management in Korea. We also represent future directions of NVMS in terms of E-Navigation(E-Nav), which is the new study item for COMSAR and NAV that has been adopted from the Maritime Safety Committee(MSC) 81st session. It concludes the future E-Nav system, when it is built, that all functions of NVMS should be used by NVMS controllers as well as mariners, and we should also consider the existing NVMS infrastructure including S/W and H/W.

• Journal of Power System Engineering
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• v.9 no.3
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• pp.5-9
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• 2005

A study on the performance and exhaust emissions of diesel engine with reducing exhaust gas temperature is performed experimentally. In this paper, experiments are performed at engine speed 2200rpm, 2600rpm and load 0%, 25%, 50%, 75% and 100% by test engine with F.W. cooler passing through exhaust gas. Main measured & analyzed parameters are exhaust gas temperature, specific fuel consumption, NOx and soot emissions etc. The obtained conclusions are as follows. (1) Specific fuel consumption is the least value at load 75% and it is decreased 1.5% after remodeling F.W. cooler. (2) NOx emission is the most value at load 100% and it is increased 30.1% after remodeling F.W. cooler. (3) Soot emission is the most value at load 100% and it is decreased 20.0% after remodeling F.W. cooler.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.57 no.1
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• pp.69-77
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• 2021

The noise environment was evaluated using the ISO recommended NR evaluation curve and PSIL (Preferred Sound Interference Level) in order to investigate the onboard educational environment according to the noise in the Motor Vessel Saehaerim, a fishing training ship under making way. As a result, NRNs were measured at 37-61 dB in accommodation areas, 44-56 dB in work areas, 37-57 dB in educational and conference areas, 83-103 dB in engine areas and 65.3 dB and 51.2 dB in the work and education areas respectively based on PSIL. The NRNs, which evaluated the cabin of the experimental ship according to the purpose, exceeded all of the indoor standard noise recommended by the ISO, and the PSIL had a generally short conversational distance within 0.25-2.3 m and 0.75-1.3 m for teaching and work areas.

• Journal of the Korean Society of Systems Engineering
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• v.18 no.1
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• pp.14-32
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• 2022

In this paper, we report the results of a conceptual study to develop of a multi-purpose medium-sized UAV that can safely perform missions in harsh maritime environments. In this study, we focused on developing UAVs capable of performing three maritime missions that urgently require the application of medium-sized UAVs: marine ecosystem management, ocean surveillance system, and response to marine accidents. Furthermore improvement points for the above three naval missions using medium-sized UAVs were derived in preparation for the problems of the existing mission performance. Finally, by developing and analyzing the utilization scenario of the medium-class UAV, the required performance suitable for each mission was defined and assigned to the related mission equipment, A new maritime management plan was proposed using the medium-class UAV system equipped with replaceable mission equipment.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2022.06a
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• pp.401-402
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• 2022

해상 상태의 변화는 어선에 탑승하고 있는 선원들의 피로도, 인지능력, 활동성 및 숙련도 변화 등과 같은 현상이 발생한다. 어선의 동요가 심해지면 특히, 멀미 증상이 발생하게 되며 개개인의 작업수행 능력이 급격히 떨어진다. 본 연구에서는 3톤급, 7톤급, 10톤급, 20톤급 어선을 대상으로 하여 파랑 중 운동 성능을 평가하여, 실해역 조건으로 어선의 선내 위치별 수직가속도 성분을 선체 운동 계산법을 통하여 계산하였다. 어선의 크기별 정박상태에서 수직가속도 스펙트럼을 사용한 멀미의 정도를 표시하였으며, MSI 계산은 입사파 방향 180도, 150도, 120도, 90도, 60도, 30도, 0도로 수행하였다. 그 결과 특정 주파수에서 입사파 방향에 따른 멀미의 가능성이 나타났다.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.18 no.2
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• pp.94-100
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• 1985

M/S Pusan 403(GT 243, 1000ps) was originally built as a research vessel on skipjack pole and line fishing in 1972. She had begun to serve as a fishing training ship of National Fisheries University of Pusan from 1974, since the interior structure has been remodelled and some weight articles have been removed, her stability is in doubt. The authors carried out an inclining experiment by using two pendulums at fore and aft with two weights on both sides. Each value obtained was compared with the IMO safety code for fishing vessels and safety regulation for fishing vessels of Korea. 1. The GZ value, being 0.207 m under light ship condition and 0.325 m under departure condition with full load, can be assumed as no impediment on her stability, 2. Under the light ship condition, GM decreased by 0.046 m and KG increased by 0.141 m, compared with the values determined at the time of official sea trial. Therefore, no impediment on the stability exists. 3. The GM decreased by 0.163 m and the KG increased by 0.173 m, compared with the values determined at the time of official sea trial. In no consideration of the free surface effects of liquid in the oil and fresh water tanks, no impediment on the stability exists. But, in consideration of the free surface effect, it may be regarded that some impediment exists.

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.2
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• pp.267-274
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• 2018

A variety of appendages are attached to coastal and offshore fishing boats to improve stability during navigation or fishing operations (stability performance and roll reduction). These appendages are generally classified into three types, which are shown in Fig. 1. The numerical calculations were conducted for the following eight cases: one case of a bare hull, three cases where a single appendage attached, three cases of a pair of appendages attached, and one case where all three appendages were attached. Table 1 presents the main dimensions of the bare hull and Table 2 describes the main dimensions of the three appendages. The fluid dynamic performance with regard to the three hull appendages was evaluated via CFD for the following cases: each of the appendages attached independently, a pair of appendages attached, and all three appendages attached simultaneously. The No. 1 appendage showed that pressure resistance was proportionally greater than friction resistances. Both Nos. 2 and 3 appendages showed comparable levels of pressure and friction resistances. The correlation between appendages was minimal in the case of pairs and Comparing the cases of the No. 2 appendage attached and all appendages attached, at 11 kn, the EHP showed an difference of 9 %.