• Journal of the Korean Magnetics Society
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• v.24 no.6
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• pp.197-201
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• 2014

As the importance of rare metal is increasing globally, Japan introduced the concept of Strategic Elements in 2004, and started Strategic Elements Project in 2007. The Goal of this project run by MEXT (Ministry of Education, Culture, Sports, Science and Technology) is to develop high-function materials and components that do not use rare or harmful elements by studying the role and characteristics of the elements that compose materials and components and decide their functions and characteristics. In September 2010, Japanese coast guard arrested a Chinese fishing boat near Senkaku Islands (Diaoyudao Islands by China), which escalated to the territory issue and eventually a big diplomatic and economic conflict. In order to put pressure on Japanese Government, China used an economic option, which is the ban of rare earth export to Japan. This incident doubled Japan's motivation to develop Strategic Elements and put more efforts into this Project. MEXT set the following three research areas in February 2012: Study of alternative materials using sufficient and harmless elements, Study of applications for the high-functions of Strategic Elements, Study of practical design for components using Strategic Elements. Through a course of gathering the opinion of professionals, MEXT settled down with the following 4 research and study areas for the Strategic Elements Project in June 2012. 1. Magnetic materials to replace Dy, Nd. 2. Catalyst/Battery materials to replace Pt, Rh/Li, Co. 3. Electronic materials to replace In, Ta. 4. Structural materials to replace Nb, Mo. This paper deals with the first area and reviews the results of the research and study as of now.

• Journal of Navigation and Port Research
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• v.40 no.1
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• pp.27-34
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• 2016

For the prevention of marine casualties, international bodies have mainly focused on strengthening ship's stability and design, maritime education and training, and improving maritime traffic environment. Statistics analysis on marine casualties showed that most of casualties occurred in coastal waters, especially by human elements. In order to review the conformity of existing prevention measures with the result of the statistics analysis, the IMO's SHELL model was applied to the established measures. As a result, ergonomic approaches were needed for the prevention of human errors in coastal waters, so that the priority should be given to the interface between ship's operator and navigational environment. For this study, Rasmussen's SRK pyramid, which showed decision making mechanism of human, and the US Coast Guard's investigation manual on marine casualties concerning the collapse of safe maritime transportation system were reviewed, and the merits and demerits within the risk assessment tools such as IWRAP, PAWSA, ES model, PARK model, and NURI model were also studied. Although the effectiveness of the existing risk assessment models was proved in ports and approaching channels, it is concluded that the need of new models for converting Korean seafarers' qualitative risk to quantitative risk was proposed so as to print hazard maps which make seafarers instinctively recognize comparative hazard levels of coastal waters.

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.1
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• pp.98-103
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• 2017

In this study, contributes to improving the state of this problem using cavitation by ultrasonic energy to reduce fuel costs, which take up a considerable part of ship operation costs, by making the use of on-board blended fuel oil more stable. An experiment simulating on-board blending methods was completed. Fuel (M.G.O & MF-180) was mixed at a volume ratio of 0.25:0.75 and, 0.75:0.25, and the effect of ultrasonic energy on blended fuel oil was examined after applying ultrasonic energy to blended fuel oil using an ultrasonic treatment unit. With the results, we confirmed the blending problem reported by vessels and residual carbon was reduced by up to 28.4%. In addition, based on the results for reduction of residual carbon content and dispersion stability, it was confirmed that the collapse pressure of the cavity due to the ultrasonic energy was effective to atomization of fuel particle and the temporary availability of mixed fuel containing a heavy fuel increased.

• Strategy21
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• s.44
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• pp.352-376
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• 2018

Through this research, the current state of naval coordination and guidance of shipping is reviewed whereupon which a suggestion is made for a novel role which satisfies the needs of the people and the country asked of the Navy. Taking into consideration the dynamic security environment, the developing relationship between the two nations on the Korean peninsula, and the influence that the Republic of Korea has on maritime security, it is made more urgent that the Navy takes a proactive course of action in terms of naval coordination and guidance of shipping. The current form of Korean naval coordination and guidance of shipping is adapted from the logical and flexible concepts of NCAPS and NCAGS and is one of many tasks that the Republic of Korea Navy must perform. However, when the Republic of Korea Navy develops blue-water capabilities with the ambitions of protecting its people and their way of life, naval coordination and guidance of shipping could potentially become one of the primary functions of the Republic of Korea Navy that the it must champion. Already, there are indications that foreign navies are, through many developments and commitment towards naval coordination and guidance of shipping, protecting its people and states' interests wherever is necessary. In the case of Chile, its Navy has taken the helm of naval coordination and guidance of shipping and has integrated various maritime organizations including the coast guard and the National Customs Service for the sake of maintaining regional maritime security, showing immediate force if necessary. Presently, as the Republic of Korea Navy looks to be a global naval power, it is important that a reprioritization of the Navy's mission is undertaken, all the while sustaining military readiness posture on the Northern Limit Line. It cannot be any more emphasized how crucial thorough military readiness posture is as a natural stance against the enemy. That being said, contributing towards international maritime security is consistent with the nation's standing. It is a fact that maritime security has been conceptualized and developed merely as a study within the Ministry of Maritime Affairs and Fisheries, the Republic of Korea Navy, and other governmental organizations, forces, and academia. Naval cooperation and guidance of shipping suggested by this research as a practical operational field is a concrete solution to what once was an abstract concept. To stand firm on its status as a maritime nation, the Republic of Korea must establish a Maritime Security Organization within its Navy and develop the appropriate doctrines. Attaining experts, developing doctrines, and cultivating the capability to deploy maritime forces will allow for the Republic of Korea to execute a primary role in keeping international maritime security and naval coordination and guidance of shipping. To fully achieve its latent potential necessitates the Republic of Korea Navy to expedite the introduction of naval coordination and guidance of shipping concepts and to establish the appropriate doctrines, operation plans, and organizations.

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.6
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• pp.620-627
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• 2017

The importance of "Golden time", the early hours for saving lives in case of an accident, is being increasingly recognized day by day. Especially for marine accidents, it may take several hours for a rescue team to arrive, depending on location. Therefore, captains should always be prepared to handle situations independently. In this paper, in order to make better use of Golden Time in an emergency, we determined what the first consideration should be when selecting a ship evacuation route from perspective of the ship operator. To achieve this, we used maritime accident judgments and ship emergency response manual to identify ship evacuation priorities. AHP analysis (decision-making hierarchy analysis) was conducted for ship operators to determine consideration priorities. As a result, it was found that ship operator consider the safety of people about 6 times more important than that of the actual ship. In order to select an evacuation route, the location of coast guard ships, port of refuge, emergency anchorage, surrounding vessels, drifting and beaching factor are taken into consideration. By using these priority considerations, the decision-making processes of ship operators in emergency situations can be improved.

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.4
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• pp.415-421
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• 2018

The Republic of Korea has a more rapidly aging society than any other country in the world. In order to prepare for the attendant challenges, this research provides basic data for policies related to aging ship officers, analyzing the relationship between elderly ship officers and marine accidents. The data used here spans 11 years, from 2006 to 2016, and the survey and regression analysis were conducted only on ship officers, excluding crew. As a result of this research, first, it was found that the number of employed ship officers older than 60 has increased 2.7 times over the past 11 years and the range of this increase was larger than for other age categories. Second, the number of elderly ship officers disciplined for marine accidents increased by around 2.6 times. Third, elderly ship officers had around 1.5 times the rate of marine accidents compared to non-elderly ship officers. Fourth, as a result of conducting regression analysis between the number of employed elderly ship officers and the number of officers disciplined, the degree of explanatory power of elderly ship officers for disciplined officials was 75.1%. Since our society will age quickly, policies such as license renewal education for elderly ship officers and regulation enforcing the quality of renewal will be needed.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.5
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• pp.647-655
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• 2021

The IMO (International Maritime Organization) is discussing the improvement of energy ef iciency of ships in order to reduce greenhouse gas emissions from ships. Currently, by applying an ORC power generation system using waste heat generated from ships, high energy conversion efficiency can be expected from ships. This technology uses an organic medium based on Freon or hydrocarbons as the working fluid, which evaporates at a lower temperature range than water. Through this, it is possible to generate steam (gas) and generate power at a low and low temperature relatively. In this study, the analysis of heat flow between the refrigerant and waste heat in the ORC power generation system, which is an organic Rankine cycle, is analyzed using 3D simulation techniques to determine the temperature change, velocity change, pressure change, and mass change of the fluid flowing of the WHRU (Waste Heat Recovery Unit) inside and the outside the structure. The purpose of this study is to analyze how the mass change affects the structure, and this study analyzed the heat transfer of the heat exchanger from the refrigerant and the exhaust gas of the ship's main engine in the ORC power generation system using this technique.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.2
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• pp.247-255
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• 2021

The Ulsan anchorage has not secured a sufficient area than the anchorage demand, and the criteria for objective evaluation are not clearly defined. In this study, a general formula to solve the problems of the current anchorage density and occupancy concept was derived, and new adequacy evaluation criteria were proposed. The proposed criteria were applied to the Ulsan E anchorage to evaluate the suitability of the anchorage. The anchorage density and occupancy of the E1 anchorage were 129 % and 122 %, respectively, showing that both evaluation techniques exceeded 100 %, requiring anchorage expansion according to the evaluation criteria. A plan to expand the anchorage was reviewed considering the traffic pattern and the distance from the pilot boarding point. Therefore, a plan to open 35˚ on a sector at the end of the Ulsan No. 1 fairway was developed, and its suitability was verified. Base on the verification results, there was a part of the overlap between the extended area and the traffic track on the south of the E3 anchorage, but the possibility of affecting the marine traffic was minimal. In addition, it was confirmed that anchorage adequacy was achieved.

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.7
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• pp.916-922
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• 2018

Recently, power plant effluent condensers received a Renewable Energy Certificate as components of hydrothermal energy (weighted 1.5 times) as one target item of the Renewable Portfolio Standard (RPS) policy. Accordingly, more attention is being paid to the value of thermal wastewater as a heat source. However, for utilization of thermal wastewater from power plants in high-turbidity areas like the West Sea of Korea, a turbidity reducing system is required to reduce system contamination. In this study, an experimental test was performed over a month on thermal wastewater from power plants located in the West Sea of Korea. It was found that water turbidity was reduced by more than 80 % and that the concentration of organic materials and nutrient salts was partially reduced due to the reduction of floating/drifting materials. To conduct a comparative analysis of the level of contamination of the heat exchanger when thermal wastewater flows in through a turbidity reducing system versus when the condenser effluent flows in directly without passing through the turbidity system, we disassembled and analyzed heat exchangers operated for 30 days. As a result, it was found that the heat exchanger without a turbidity reducing system had a higher level of contamination. Main contaminants (scale) that flowed in to the heat exchanger included minerals such as $SiO_2$, $Na(Si_3Al)O_8$, $CaCO_3$ and NaCl. It was estimated that marine sediment soil flowed in to the heat exchanger because of the high level of turbidity in the water-intake areas.

• Journal of the Korean Society of Marine Environment & Safety
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• v.25 no.5
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• pp.550-559
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• 2019

The sinking of the M/V SEWOL in April 2014 was not a mere marine accident, but a marine catastrophe. This grim case developed into a social tragedy that impinged the national sentiment and communal integrity. It is imperative that thorough provisions and measures be outlined at the national level with regard to massive marine accidents, oil pollution, and natural disasters that might critically affect government affairs. Pivoting on "The Black Swan Theory," a concept of improperly rationalizing a national crisis based on uncertainties, this research assesses a variety of response strategies that minimize the national economic and social damage caused by a large-scale marine disaster. Along with the effort of minimizing any potential defects in each protective barrier, the "Black Swan Detection System of the Marine Disaster" needs to be incorporated to prevent cases wherein such defects lead to an actual crisis. Maritime safety must be systematically unified under a supervisory organization, and a structure for maritime crisis on-scene command and cooperation must likewise be established in order that every force on the scene of a marine disaster may act effectively and consistently under the direction of an on-scene commander.