• Journal of the Korean Society of Marine Environment & Safety
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• v.2 no.1
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• pp.11-33
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• 1996

This work aims at examining the navigational safety of the entrance channel of Inchon harbour and suggesting the way to improve ship's navigation of the navigational safety at Inchon, that small ships such as fishing boats and barges coming out of the harbour through the East Channel cause major threat to the inbound large ships using the channel. An additional new waterway, therefore, has been recommended to be established in the middle of the East and West Channels so that the outbound small ships can use it. A waterway design simulation methodology has been applied to examin the sagety of the newly suggested channel. Minor chansge has been made to the original design after the simulation experiment, and the corrected final design of the waterway has been suggested to be implemented as soon as possible.

• Journal of the Korean Society for Marine Environment & Energy
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• v.17 no.4
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• pp.318-323
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• 2014

When a disabled ship is being towed in a seaway, the speed and direction of the towed ship are estimated by using the towing force and direction of the selected tug boats at the predicted sea conditions including the wind and currents. In this paper, prediction method at the towing conditions of the various towing operations for a disabled ship are studied. The proposed calculation method suggests firstly the method to import the speed and resistance of the forward direction of the towed ship calculated by the existing computer program, second, the method to calculate the speed and resistance of the towed direction of the towed ship acquired from the selected tug boats at the initial towing conditions and lastly, the method to calculate the speed and resistance of the towed direction for the towed ship at the stable towing conditions. These calculation methods have been applied to the computer program and this program has been approved to be a useful program, capable of appropriately predicting the towed ship's conditions.

• Proceedings of KOSOMES biannual meeting
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• 2005.05a
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• pp.37-43
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• 2005

Recently, many ships such as fishing boats, cargo ships, high speed ferry boats are visiting Mokpo harbor. In particular, many marine accidents rave been occurred at this area because of the narrow channel, a thick fog, the existing of the shallow waters etc. However there is no suitable ships' routeing system which takes account of today's traffic situations in this area. This study aims at the settling of hazardous factors to mitigate the danger to vessels in mokpo harbor and to secure the safety qf maritime environment.

• Journal of Advanced Marine Engineering and Technology
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• v.38 no.4
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• pp.495-501
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• 2014

Users of passenger ships and cruise ships are rapidly increasing year by year, and the needs of the floating architecture are newly come out. But the studies about the passengers' safety and the countermeasures against incidents on board the ships are rare, although the ships' incidents are occurred averagely 15 cases per year during last 10 years. For the purposes of the analysis of the safety consciousness and gathering the some of input data for evacuation simulation for Korean passengers on board ships, this study performed surveys targeting ordinary 394 passengers who are not specially trained and/or accustomed with onboard living conditions. The results are the followings. The reliability on ships' safety is surveyed as 32.3%. Only 14.6% of respondents are aware that there were safety education on board ship during sailing. And 42.2% and 40.9% of respondents answered that they saw the map of emergency routes and knew where the life boats are, respectively. And 73.3% select crews' direct or in-direct(like announcement by indoor broadcasting system) guidances as the most effective evacuation method.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2023.11a
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• pp.114-115
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• 2023

Research on eco-friendly ships is being actively conducted due to the strengthening of environmental regulations in the shipping sector by the International Maritime Organization (IMO). However, most studies are on large ships, and research on small ships is insufficient. Since most fishermen operate small boats, research on eco-friendly fuel vessels is necessary. This study performed resistance performance analysis, model tests, and POW tests to develop a hybrid electric propulsion ship, and compared and verified the CFD and model test results.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2009.10a
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• pp.40-41
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• 2009

In general, ships are towed to keep the safe operations in harbor or channel by tug boats. Due to increase in ocean traffic, many accidents are happened in harbor or channel in these days. Therefore it is necessary to predict manoeuvrability of tug-barge system, and to assure the safety of that system. Turg-barge system is composed of tug boat, barge, and towing cable, connecting both ships. Manoeuvring equations of tug-barge system are suggested, and the scopes of model tests are discussed to establish the mathematical models for tug boats in this paper.

• 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 Navigation and Port Research
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• v.33 no.1
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• pp.1-7
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• 2009

Navigation speed control is an important factor to improve the traffic safety, it is only researched about maximum speed control until now. Recently, there are lots of the low speed vessels including towing boats, carry heavy shipbuilding blocks in the Korean waters, so the danger degree of navigating vessels was increasing more and more. This paper analysed the effectiveness of minimum speed control with the operation burden's decrease, and it proposed the proper the minimum navigation speed of each traffic volume. Main results of this research are as follows. (1) in the case of 5 ships/hour, minimum speed control is effective if the lowest speed is fixed more than 5kts. (2) in the case of more than 10 ships/hour, speed control is some effective if the lowest speed is established 7kts. (3) But, when there are many ships in the waters, minimum speed control is not effective because distances between ships become near and ships navigate for a long time by a lot of ship having a few difference of relative speed.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.39 no.2
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• pp.134-142
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• 2003

Most of the vibration and noise generating in small boats come from shipboard machinery such as main engine, generator and auxiliary machinery etc. In order to build up the comfortable environment for the crew and to reduce the ambient noise, and provide basic materials for reasoning selection application, the design under allowable vibration & noise conditions and the examination of vibration condition of the new ships, this paper researches the frequency spectrum and order analysis of vibration and noise. The obtained results are summarized as follows : Through comparing the small boat internal noise with the regulation of IMO and DNV, it revealed that the noise level of main engine room accords with the standard, and the noise of other places are beyond the values. In this paper, two boats are analyzed, which are same type, same size and power, but the main engines noise of them is different. In order to search the noise source, the noise of main engine room and relative parts are measured. The third order of measured points is dominant in frequency domain by the order analysis.

• Journal of Ocean Engineering and Technology
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• v.27 no.4
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• pp.45-54
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• 2013

In this study, various types of composite materials and adhesives that are actually used in the shipbuilding field for small ships, leisure boats, and fishing boats were applied in the hand lay-up method and vacuum infusion method to manufacture specimens. Then the tensile strength, tensile modulus, flexural strength, and flexural modulus values of these specimens were obtained. In addition, the barcol hardness and fiber content were obtained from the specimens. The results showed that the strengths of the specimens manufactured using the vacuum infusion method were higher than those manufactured using the hand lay-up method. Moreover, the barcol hardness and fiber content were also higher in those manufactured using the vacuum infusion method. The specimens manufactured using the vacuum infusion method were thinner despite their large fiber content.