• 한국항해항만학회지
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• 제32권8호
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• pp.569-576
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• 2008

전세계적으로 물동량이 증가하고 동시에 지난 10여년간 VTS는 급격한 성장을 하여 왔다. 그러나 VTS가 생겨난 이후 15년간 VTS 관제사의 업무량에 대한 관심과 연구는 미흡하였다. VTS 관제사의 업무량을 측정하기 위해 우선, Port-MIS 자료와 De-briefing자료를 이용하여 7일간 입출항 척수를 시간-톤수별로 구별하여 조사한다. 그러나, 한 척의 선박이 입항하더라도 관제사가 느끼는 부담의 정도가 달라지므로 선종, 크기, $L^2$ 환산치등을 조사한다. 여기에 설문조사를 통하여 구해진 관제 비관제 척수를 1과 0.3의 가중치를 주어 환산관제척수를 구한다. VTS 업무량에 영향을 주는 요소인 관제구역 크기, 사고발생 빈도, 거대선, 위험선을 조사 분석하여 관계식을 정립하고, 이 연구의 결론인 복합환산 관제척수(실제로 관제사에게 부담이 되는 업무량 교통량)를 산출한다.

• 한국해양바이오학회지
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• 제1권1호
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• pp.40-47
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• 2006

Large scale marine biodiversity studies in China have been carried out for more than half a century since the founding of the Institute of Oceanology, CAS, in 1950. Through a series of coastal and multi-disciplinary oceanographic investigations in the shelf seas and biodiversity studies since the late fifties, a total of 20,278 species of marine biota have been recorded upto 1994. Recent intensive studies have further revealed the richness of marine biota of the China seas,a great number of marine species have been found and many new taxa established. The total species number of main biotic groups increased about 50 % of that estimated in 1994. The results have promoted the fast development of China's marine fisheries, medicine (drug) and biodiversity research, and attracted many scientists, particularly bio-technologists, to join their studies. Environmental deterioration and human activity strongly stressed the sustainable development and conservation of marine bio-diversity, and resulted in the increase of end angered species as record ed in the new published ${\ll}$China Species Red List${\gg}$ with the threatened category of species assessed by adopting the new IUCN criteria. To further reveal the high diversity and their history, present status and future of marine organisms existed in the world ocean, an international Project ${\ll}$Census of Marine Life (CoML)${\gg}$ was established in 2000 in the USA. Scientists predicted that 2 to 3 times of numbers of the known species will possibly be found in various marine habitats, particularly the abyssal ocean. The Research Plan and the Projects were briefly introduced, and the relationship between marine biodiversity and biotechnology was discussed. The Project planned to apply new and high techniques and new equipments on board research vessel and in laboratory. Brief review of recent advances of Chinas' marine biodiversity and biotechnology studies indicated that fascinate results have been achcieved; but further effort should be made to promote the continuous advance of our basic researches and their application in related production and maintain sustainable development.

• 수산해양교육연구
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• 제27권2호
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• pp.441-451
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• 2015

The one-year onboard training, which has been implemented since 1988 according to the STCW Convention in 1978, is a crucial part of cadets' training and education. The choice of training shipping company is important that like a internship. This basic study is for the satisfaction at the shipping companies that trains cadets the Mokpo National Maritime University. The satisfaction for onboard training consists of a conscious, educational and environmental parts with six demographic characteristics and carried out the questionnaire survey of 206 cadets in shipping companies. The low parts of satisfaction are implemented cross tabulation analysis and in-depth interview for realize the reason. In this paper, the satisfaction from environmental part($3.83{\pm}0.75$) is high but conscious part($3.35{\pm}0.86$) and educational part($3.33{\pm}0.79$) are low. In demographic characteristics, male in gender, apprentice officer in duty, others in kind of crew, container in kind of vessel and 30,000~100,000 tons in size of vessel are high satisfaction in general. Specifically, feeding service($4.02{\pm}0.75$) in environment, influence on future vision($3.65{\pm}0.84$) in consciousness, goal for training($3.50{\pm}0.65$) in education showed the highest level in satisfaction.

• 한국항해항만학회지
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• 제36권4호
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• pp.279-284
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• 2012

This study aims to identify the degree of safety when mariners take their actions in several different situations. We have carried out many experiments to observe mariners' behavior and then measured the safety level based on their actions to avoid dangerous situations of ships collision. One of the most important actions that mariners have to take, either as their daily routine or when they are in a collision situation and then want to avoid that situation is the lookout. In this paper, behaviors on the lookout have been defined as a standard sequence of three steps which are "time of first detection", "time of recognition as risky vessel" and "time of starting avoiding action", and the suitability and applicability of the definition have been shown. And also we propose the risk assessment on ships collision and the recommendation for reducing ships collision at sea. Some analyzing results and the application of the results are reported. By combining these knowledge and some systematic studies, we propose the risk assessment on ships collision and the recommendation for reducing ships collision at sea.

• 해양환경안전학회지
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• 제24권3호
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• pp.302-310
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• 2018

Despite the accident rate for fishing vessels accounts for 70% of all maritime accidents, few studies on such accidents have been done and most of the them mainly focus on causes and mitigation policies to reduce that accident rate. Thus, this risk analysis on sea accidents is the first to be performed for the successful and efficient implementation of accident reducing measures. In risk analysis, risk is calculated based on the combination of frequency and the consequence of an accident, and is usually expressed as a single number. However, there exists uncertainty in the risk calculation process if one uses a limited number of data for analysis. Therefore, in the study we propose a probabilistic simulation method to forecast risk not as a single number, but in a range of possible risk values. For the capability of the proposed method, using the criteria with the ALARP region, we show the possible risk values spanning across the different risk regions, whereas the single risk value calculated from the existing method lies in one of the risk regions. Therefore, a decision maker could employ appropriate risk mitigation options to handle the risks lying in different regions. For this study, we used fishing vessel accident data from 1988 to 2016.

• Journal of Advanced Marine Engineering and Technology
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• 제21권5호
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• pp.564-570
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• 1997

The most important factor for the desalination system is the fresh water production cost dependent upon the possible energy source which should be obtained easily and with low price. Recently in Korea the demand of LNG, as a cheap and clean energy which does not cause an environmental problem, has sharply been increased. In general, LNG is storaged in a tank as a liquid state below -162 'C. When it is serviced, however, the LNG absorbs energy from a heating source and transforms to the gaseous state with high pressure. During this process a huge amount of cold energy accumulated in LNG is wasted. This waste cold energy can be utilized for producing fresh water from sea water using a sea water freezing desalination system. In order to develop a sea water freezing desalination system and to establish its design technique, a qualitative and quantitative data regarding the freezing behavior of sea water is needed in advance. The goal of this study, therefore, are to reveal the freezing mechanism of sea water, to measure the freezing rate, and to investigate the freezing heat-transfer characteristics. The experimental results help to provide a general understanding of the sea water freezing behavior in a Rectangular vessel cooled from below.

• Journal of Advanced Marine Engineering and Technology
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• 제25권6호
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• pp.1228-1236
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• 2001

In this study, CT specimens were prepared from ASTH A5l6 steel which was used for pressure vessel plates for moderate and lower temperature service. And we got the fellowing characteristics from fatigue crack growth test carried out in the environment of room and low temperature at $25^{\circ}C$ , $-30^{\circ}C$, $-60^{\circ}C$, $-80^{\circ}C$, $-100^{\circ}C$ and $-120^{\circ}C$ and in the range of stress ratio of 0.1, 0.3 by means of opening mode displacement. At the constant stress ratio, the Threshold stress intensity factor range ΔAKth in the early stage of fatigue crack growth (Region I) and stress intensity factor range $\DeltaK$ in the stable of fatigue crack growth (Region II) was increased in proportion to descend temperature. It assumed that the fatigue resistance characteristics and fracture strength at low temperature is considerable higher than that of room temperature in the early stage and stable of fatigue crack growth region. The straight line slope relation of logarithm da/dN-$\Delta$K in Region II that is, the fatigue clack growth exponent m increased with descending temperature at the constant stress ratio. It assumed that the fatigue crack growth rate da/dN is rapid in proportion to descend temperature in Region II and the cryogenic-brittleness greatly affect a material with decreasing temperature.

• Journal of Advanced Marine Engineering and Technology
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• 제32권7호
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• pp.1019-1029
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• 2008

In this study, visual investigation of sprays and flames has been performed and soot formation in Diesel and GTL fuels has been compared in a specially designed Rapid Charging Combustion Vessel (RCCV) under various ambient gas $O_2$ concentrations and two injection pressures. It has been concluded that soot in the mixing-controlled combustion of Diesel and GTL fuels has similar tendency to be formed in the leading portion of the jet boundaries. Auto-ignition delay for GTL fuel is shorter than that for diesel fuel. The temporal and special variation of soot concentration in the diesel flame jets at various $O_2$ concentrations was correlated with the heat release rate. Soot concentration appears in the regions when diffusion combustion starts, and its concentration reaches maximum at the peak of heat release curve and then decreases due to oxidation. Visualization by shadowgraph method showed that soot decreases with lower $O_2$ concentration, and higher injection pressure.

• Journal of Advanced Marine Engineering and Technology
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• 제35권4호
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• pp.443-450
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• 2011

연료가스 압축 시스템은 중급의 FPSO에 설치되며, 이 시스템에서 서지를 방지하기 위하여 안티 서지 밸브가 사용되어진다. 만약 서지가 발생하게 되면 시스템의 파괴를 초래할 수 있으므로 안티서지 밸브는 반드시 구조강도와 구조안전성 평가가 수반되어야한다. 특히, 비상시에도 밸브는 구조안전성과 그 성능을 보장해야 된다. 이 연구에서는 안티서지 밸브의 구조강도와 구조안정성 평가를 수치해석을 통하여 수행하였다. 형상모델은 유니그래픽스 NX4.0을 사용하였으며 시뮬레이션은 ANSYS Workbench 12.1 버전을 이용하였다. 밸브의 허용 강도와 안전계수는 ASME Boiler & Pressure Vessel Code를 참조하였다.

• 해양환경안전학회지
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• 제14권4호
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• pp.309-316
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• 2008

해상에서의 선박 임장임검과 불심검문의 법적성격과 강제력을 수반한 영장 없는 선박 임장임검과 불심검문의 가능성 및 그 허용범위의 문제를 특히 미국 및 일본의 경우와 비교하여 고찰하였다. 선박의 임장임겁이나 해상에서의 선박에 대한 불심검문이 원칙적으로 육상의 불심검문과 같은 성격을 갖지만, 선박의 특수성과 육상과는 다른 해상에서의 상황의 특수성을 고려 한다면, 선박의 임장임검이나 해상에서의 불심검문이 육상의 불심검문과 같이 항상 임의적으로 이루어져야 한다고 보기는 어려운 측면이 있는 것으로 판단된다.