• Journal of Korean Society of Transportation
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• v.28 no.6
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• pp.33-42
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• 2010

Recently, the reduction of greenhouse gases(GHG) for climate change is the most important international issue. In order to control efficiency GHG emission rate reduction, it is essential to establish GHG emission inventory preferentially. The emission of ships that are emitting its $CO_2$ in international waters is becoming chief among the issues which country is put under an obligation. In the IMO reports, shipping is estimate to emit 1,046million tonnes of $CO_2$, which corresponds to 3.3% of global emission during 2007. International shipping is estimated to have emitted 870 million tonnes, about 2.7% of global emission of $CO_2$ in 2007. In this study, the general information of GHG emission, based on fuel consumption statistic, Tier 1, and the emission inventory is calculated to break down in to domestic and international emission. The GHG emission from ships in Korea was total 31,646 Gg $CO_2$-eq in 2009, which is included fishing, Korea flag coastal ship, Korea flag ocean going ship and foreign flag ships. And domestic emission and international emission was 5,398Gg $CO_2$-eq, 7,630Gg $CO_2$-eq and foreign flag ship was 18,618Gg $CO_2$-eq respectively.

• Journal of the Korean Society for Marine Environment & Energy
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• v.16 no.3
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• pp.202-210
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• 2013

As incomes increase, interest in ocean leisure picks up. As a result, a lot of research and developments on hull form design and production of planing boats, mostly used for ocean leisure, are needed. Analysis in researches on resistance of planing boats shows that resistance characteristic of planing boats is different from resistance characteristic of general boats because the former is fast, and its wetted surface is very small. Using Savitsky formula widely used in the calculation of effective horse power in shipbuildingyards, and propulsion system and engine manufacturers, this study calculated total resistance of a research planing boat. Then it analyzed the flow characteristics of the planing boat through theoretical analysis and wind tunnel experiment, and computed air resistance and lift force by changes of speed and trim angle. It also compared and analyzed result of theoretical analysis and experiment of the ratio of air resistance to total resistance under variations of velocity and trim angle. When the study is used to estimate more accurate effective horse power, it is expected to remedy abuses of unnecessarily installing high-powered engine. As nature disasters due to abnormal changes of weather increase, interest in greenhouse gas grows. International Maritime Organization (IMO) legislated Energy Efficiency Design Index (EEDI) and Energy Efficiency Operational Indicator (EEOI) to reduce ship greenhouse gas emissions. But this index will be applied to over 400 tons ships, small ships, emitting more greenhouse gases than larege ships per unit power, will dodge the regulations. Thus, this study indicated a problem by calculating greenhouse gas emissions of an ocean leisure planning boat (a small ship), and suggested the need for EEDI of small ships.

• Journal of Advanced Marine Engineering and Technology
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• v.41 no.1
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• pp.15-20
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• 2017

The International Maritime Organization(IMO) has adopted and implemented compulsory regulation for reducing greenhouse gas emission that cause global warming. However, with global warming underway, the IMO plans to enforce voluntary carbon dioxide emissions reduction based on the Ship Energy Efficient Management Plan and the Energy Efficiency Operational Indicator(EEOI) in the near future. Large container ships sail at low speeds in order to save fuel and reduce carbon dioxide emissions. However, bulbous bows designed for high-speed ships decrease fuel efficiency by acting as resistance when reduced speeds are adopted by large container ships. In order to adopt low-speed operations and increase fuel savings, the bulbous bow of a large container ship was modified into the proper shape and size. Fuel consumption was compared for checking the result of EEOI before and after modifying the bulbous bow adopted on low speed operation of large high-speed ships. The results confirmed much larger carbon dioxide emissions reduction than expected. If EEOI would be implemented as compulsory regulation for reducing carbon dioxide emissions, bulbous bow modification can be considered as one of the fuel saving methods for the high-speed ships.

• Journal of Advanced Marine Engineering and Technology
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• v.38 no.7
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• pp.877-882
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• 2014

The reduction of CO2 emission has been discussed in the Marine Environment Protection committee in the International Maritime Organization as the biggest causes of GHG for the purpose of indexing CO2 amounts released into the atmosphere from ships. Accordingly, various methods including the change in the hull design to improve energy efficiency, the coating development to reduce friction resistances, the additives development for improving thermal efficiency in an engine, the low-speed operation to reduce fuel consumptions, and etc. have been applied. The main engine of a ship is an electronic engine for improving the efficiency of the whole load area. However, marine generator engines still use mechanical drive engines in intake, exhaust, and fuel injection valve drive cams. In addition, most of marine generator engines in ships apply a part-load operation of less then 80% due to an overload protection system. Therefore, marine auxiliary diesel engine set at 100% load is necessary to readjust in order to efficient operation because of part-load operation. The objective of this study is to report the results of the part-load fuel consumption improvement by injection timing readjust to identifying the operational characteristics of a marine generator engine currently operated in a ship.

• Journal of the Society of Naval Architects of Korea
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• v.54 no.3
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• pp.171-186
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• 2017

This paper introduces a study on ship performance in waves to consider the effects of added resistance in the early stage of hull-form design. A ship experiences a loss of speed in actual seaways, hence this study proposes the overall procedure of a new design concept that takes into account the hydrodynamic performance of ship in waves. In the procedure, the added resistance is predicted using numerical methods: slender-body theory and Maruo's far-field formulation, since these methods are efficient in initial design stage, and an empirical formula is adopted for short waves. As computational models, KVLCC2 hull and Supramax bulk carrier are considered, and the results of added resistance and weather factor for test models are discussed. The computational results of vertical motion response and added resistance of KVLCC2 hull are compared with the experimental data. In addition, the sensitivity analysis of added resistance and weather factor for KVLCC2 hull to the variations of ship dimensions are conducted, and the change of the added resistance and propulsion factors after hull form variations are discussed.

• Journal of the Korean Society of Marine Environment & Safety
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• v.22 no.5
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• pp.576-582
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• 2016

To cope with international regulations, such as Energy Efficiency Design Index (EEDI), Ship Energy Efficiency Management Plan (SEEMP) and so forth, and to enforce limitations on $CO_2$ emissions, green-ship technology to lower fuel consumption has been actively researched, and the development of an energy-saving device (ESD) is being pursued. In order to design an ESD for small and medium-sized domestic vessels, an analysis on flow characteristics has been performed in the present study. Through a model test and numerical analyses, the characteristics of flow around the stern bilge and bulb have been compared to improve wake quality and resistance performance. As a result of these comparisons and analyses, a vertical plate has been adopted,, as a new ESD. Design criteria for the proposed ESD are also suggested. By applying this new ESD, it is expected that the total resistance and average nominal wake can be reduced by 3.04 % and 18.8 %, respectively.