• Journal of the Korean Society for Marine Environment & Energy
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• v.9 no.4
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• pp.253-262
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• 2006

In this paper, collision analysis is carried out between two FRP fishing boats. A computer simulation with finite element method is used to accomplish this objective. At first, a detailed geometric model of the boat is constructed using 3-D CAD program. The formation of a finite element from a geometric data of the boats is carried out using HYPERMESH that is the commercial software for mesh generation and post processing. Twelve collision configurations are established by combining two kinds of contact angle($90^{\circ},\;135^{\circ}$) and three different speed(5, 10, 15knot) for small and large boats. Collision analysis is accomplished using DYNA3D. Stress distribution and deformation shape are investigated for each collision condition. In general, $90^{\circ}$ collision angle generate larger stress than $135^{\circ}$ case and the collision for two moving boats showed larger maximum stress than the case that one is moving and the other is stationary. When analysis is carried out until 150ms contact parts of two boats are broken for 10 and 15knot collision speed, in which maximum stress is larger than ultimate strength of the material.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.25 no.2
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• pp.82-86
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• 1989

This paper is concerned with the effects of temperature of diesel fuel on combustion characteristics and engine performance in a home-made precombustion diesel engine for small-sized fishing boat. The results may be summarized as follows: 1. The fuel injection timing was delayed with increase in temperature for diesel fuel, and remarkably delayed at low load. 2. The point of maximum pressure was delayed with increase in temperature for diesel fuel, the maximum pressure decreased with increase in temperature for diesel fuel but increased with increase in load. 3. The brake specific fuel comsumption (BSFC) decreased with increase in load, the optimum temperature of the heated fuel was about 15$0^{\circ}C$. 4. The smoke emissions increased with increase in load and temperature for diesel fuel.

• Journal of Ocean Engineering and Technology
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• v.24 no.5
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• pp.75-80
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• 2010

Fiberglass-Reinforced Plastic (FRP) composites have been used for small fishing boats and leisure boats for many years. These composites have different physical characteristics, depending on the constitution of lay-up and manufacturing method. Recently, new manufacturing methods, such as vacuum infusion, have been used to make the composites lighter and stronger. In this research, the mechanical properties of fiberglass reinforcements with constitution of lay-up, manufacturing method, and two different resins were investigated experimentally. It was found that the mechanical properties of FRP composites increased with increasing thickness, with the use of vacuum infusion method, and with the use of vinyl ester resin. The mechanical properties of diverse FRP composites can be used as a practical guide for selecting appropriate materials for specific applications.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2012.06a
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• pp.100-101
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• 2012

According to growing the leisure boat market, safety-related and weather information have been required by different users with different electronic devices. NAVTEX messages transmitting worldwide from local stations are a kind of useful service, even for non mandatory carriage requirement vessel, such as small or fishing vessels. However, it is not easy for all users to recognize intuitively. This paper is to implement the NAVTEX message on tablet PC, indicating warning positions of message on Android-based google map.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.16 no.6
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• pp.119-123
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• 2016

In the coastal area, many kind of vessels are operating and exposed to the various marine accidents. In particular, small-size vessels, which are not equipped with the safety equipment, are in the defenceless state to the marine accidents such as the accident according to vessel's own state caused by the diverse reasons and the collision with the neighborhood vessels and objectives. So it is necessary to resolve these situations through the inexpensive equipment. This paper implements the function that can detect vessel's own motion using Smart Phone. if the motion is over the threshold value assigned, this function decides that the current situation is dangerous for this vessel. So this function informs Smart Phone's ower in the vessel and the control center of this situation. This function can be applied to small-size vessels, such as fishing boating, passenger ship, and leasure boat, which have few the safety equipments, and then improve vessel's safety navigation.

• Proceedings of KOSOMES biannual meeting
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• 2005.05a
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• pp.155-159
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• 2005

Analysis target ship is not introduced yet in domestic as steel yacht that is getting into the spotlight by leisure life in Australia or Japan. Sailing yacht or Yacht for leisure time made of FRP into controlling power fare mainly and the design and made of latest fishing boat and something of domestic is consisting mainly. To need investigated for concept is various kinds overall strength as that use mainly steel wire material structurally of steel yacht by small crafts about Longi strength, Transe strength portion even of design safety factor at subject to do Rule's allowable stress enough stable structure accomplish. But it is assessment of part intensity that become refer to most in small size ship.

• Journal of Navigation and Port Research
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• v.47 no.6
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• pp.358-366
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• 2023

This study aimed to provide a solution for improving ship collision alert of the 'accident vulnerable ship monitoring service' among the 'intelligent marine traffic information system' services of the Ministry of Oceans and Fisheries. The current ship collision alert uses a supervised learning (SL) model with survey labels based on large ship-oriented data and its operators. Consequently, the small ship data and the operator's opinion are not reflected in the current collision-supervised learning model, and the effect is insufficient because the alarm is provided from a longer distance than the small ship operator feels. In addition, the supervised learning (SL) method requires a large number of labeled data, and the labeling process requires a lot of resources and time. To overcome these limitations, in this paper, the classification model of collision alerts for small ships using unlabeled data with the semi-supervised learning (SSL) algorithms (Label Propagation and TabNet) was studied. Results of real-time experiments on small ship operators using the classification model of collision alerts showed that the satisfaction of operators increased.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 1998.10b
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• pp.11-25
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• 1998

Many Countries have made efforts to assist ships navigate accurately , safely and expeditiously for the safety control against increasing marine traffic , in their coastal waters. However, they are exposed in spite of these efforts,to risks of casulaties and marine polluation caused by traffic congestion when ships are navigating through waterways approaches to ports or harbors and in narrow fairways. Therefore, efficient control of VTS in Port is necessary nowadays to provide ships with necessary service , which interacts with shipping and organize the flow of traffic so as to maximize the efficiency of the port or harbor while minimizing the risk of accident and environmental pollution. Even though the navigation condition of ships is very inferior compared to other ports in Korea, such as the big difference between the ebb and flood tide, the frequent fog, the narrow fairway , the density of navigation traffic in Inchon Port is high and transportation quantity of dangerous cargoe increases gradually. In cosideration of the characteristics of natural circumstance and traffic circumstance the VTS established newly in Inchon port have to operate efficiently. The purpose of this study is to help efficient operation of VTS in Inchon port by accomplishing both the literature research and questionnaire survey. Questionnaire survey was read to the VTS personnel in Inchon Port and customer familiar to Inchon Port such as ship navigators, pilots, shipping companies and so on. Most of ship navigators who occupy half of the respondents are Korean Officer who had responded while they were calling at Inchon port. The conclusions and recommendations includes ; First, the service area should be extended over Designated area to provide the vessel with navigational assistance service regarding the information of traffic congestion area, fishing boat and small ship's activities. Second, the types of information service to be offered are ship's movement and weather condition inthe vicinity of the port and state of fairway in the approaching channel to thte fairway. Third, VTS personnel should be upgraded by the on-the-job training and continuous simulation training as well as supplement of the qualified personnel for VTS operation. Fourth , the Harbor Master System to be introduced for safe navigation and efficient port operation.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.42 no.6
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• pp.657-663
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• 2009

This paper reports the strandings of sea turtles on Korean shores monitored for the first time in 2008. A total of 19 sea turtles, consisting of 12 greens and 7 loggerheads, were recorded as stranded from the east coast to the south including Jeju Island. Reported strandings reached a peak in July and dominant area was Jeju Island. The curved carapace length of loggerhead sea turtles ranged 65-84.2cm and that of green sea turtles ranged 39.2-90cm, indicating most of them were immature to sub-adult. Out of 19 turtles, 11 were found dead with unknown reasons. Possible causes of death may include drawning by fishing gear, swallowing of marine debris, boat collision, and diseases. An immature green sea turtle tagged with a satellite transmitter spent winter near Jeju Island where it was released, suggesting that the Island provide immature greens a feeding ground. Considering thousands of sea turtles crawl on Japanese shores for nesting every year, the number of sea turtles reported in Korean waters was relatively small. Therefore, it is suggested that an appropriate monitoring system be necessary to protect and conserve endangered sea turtle species in Korean waters.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.4
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• pp.804-810
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• 2017

Distress accidents occur annually by and failure of sea rescue and time delay lead to fatal accident. In the event of maritime distress, most of the equipments used for search and rescue are in responsible for the position of ships. An MOB equipment is a representative equipment for lifesaving and uses AIS communication method. However, the MOB equipment has problems of interference with existing vessel traffic process and it is difficult to apply because there is no proper certification standard. Therefore, this paper proposes a maritime search and rescue supporting system using smartphone. Utilizing the widely constructed IT infrastructure, it collects position information of the fishing boat and leisure ship using GPS embedded in the smartphone. Also the developed system supports to participate in the rescue by sending the information about the occurrence of the survivor in a certain area to the ship operator.