• Journal of the Korean Society for Marine Environment & Energy
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• v.9 no.2
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• pp.92-97
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• 2006

Hull forms of a high speed small boat have been developed through numerical studies. A round bilge type hull form has been drived form a using chine hull form with HCAD, a hull form variation software. Wave resistance and the flow fields around the ships have been computed using well-known software, WAVIS. This software employs Rankine source method with non-linear tree surface condition as well as dry transom boundary conditions. The round bilge hull form showed better resistance performance than to the chine hull form for the whole speed range. However, considering the building and labor costs of the small shipyard, the chine hull form has been selected and its wave resistance characteristics has been improved by modifying the bow regions and applying the stem wedge. It is found that the effect of stem wedge is quite satisfactory to improve the resistance characteristics of high speed chine hull form.

• Journal of the Korean Society of Marine Environment & Safety
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• v.13 no.3
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• pp.229-234
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• 2007

Currently offshore fisheries are one of shrinking industries and fishermen are getting older. Moreover it is difficult to work fisheries for decreasing fishermen as the time goes. Two people per a boat work together at least for proper fisheries. If the unskilled fisherman boards on boat, it will make some troubles to speak each other and diminish the efficiency of working because one person should control the boat. So it need to study the remote control system for leasure and outboard engine that can control and work at the same time. The remote control system is consisted of engine, steering gear and forward reverse neutral gear controls. These three controls are made by position and speed control using DC motor, and microcontroller is used to control the engine speed and rudder angle. This system can be controled and worked alone and we tested the system at sea and confirmed that the system works properly.

• Journal of Navigation and Port Research
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• v.43 no.4
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• pp.250-255
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• 2019

The objective of this study was to analyze the risk of collision accidents to the VTSOs (Vessel Traffic Service Operators) as small ferries and fishing boats are expanded for monitoring targets. The VTSOs was surveyed, the scale of the small vessels defined and the course of general cargo vessels and small vessels along the Busan VTS area investigated for three days. From calculating the risk with CoRI, patterns of increased or decreased risk due to course deviation were similar, and there was no significant difference between the maximum values and the minimum values. In addition, most VTSOs responded that the minimum time required was approximately three minutes to safely instruct in encounter situation, however, the collision risk with a small vessel is very rapidly changing within the three minutes, which is likely to increase the workload and decrease the concentration of the VTSOs. The objective of this study was to investigate the effect on VTSOs with respect to the expansion of small vessels as collision risk, it is expected that it will contribute to the establishment of a suitable scale for the target vessels for VTS through the analysis of each index of the CoRI model and various case studies.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.2
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• pp.238-246
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• 2021

Collision of small vessels such as fishing boats cause great personal injury. Prior to this study, the collision prevention algorithm was developed to assess the collision risk and make the collision alarm. However, a service provided for safety, such as a collision warning, not only prevents risks, but also requires a certain degree of user satisfaction to function effectively. In this study, the collision prevention algorithm for small vessels was improved to be more practical, and the effects of the improvement were confirmed by applying the algorithm. A survey conducted on the users of the collision warning service confirmed the user requirements for improving the accuracy of the collision warning system and reducing the volume and number of alarms. Accordingly, the algorithm was improved for user satisfaction, and the actual vessel experiment was performed applying the improved algorithm in an actual maritime environment. As a result, the frequency of alarm occurrence decreased compared to former algorithm, but the alarm was relatively steadily generated in dangerous situations. It was analyzed that the accuracy and practicality of the collision alarm were improved. If the practicality and reliability of the improved algorithm are verified in the further study, it will be able to effectively contribute to the prevention of collisions of small vessels.

• Journal of Advanced Navigation Technology
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• v.16 no.6
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• pp.920-926
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• 2012

In this paper, marine accidents recently happened in Korea and Japan for 5 years, especially through the analysis of accident characteristics for fishing vessels, including small vessels were analyzed. Also propose a new maritime safety communication network in the form of a comprehensive considering the wave propagation characteristics and operational characteristics of radio communication equipments should be installed in the vessel through comprehensive analysis of the regulation according to the radio equipment and the ship's location identification device installation and operation.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2012.06a
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• pp.542-544
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• 2012

조선기술의 발달과 해운업체의 요구로 선박이 점차 고속화 대형화됨에 따라 선박의 통항량은 매년 증가하고 있으며, 해양사고의 위험도 함께 높아지고 있다. 또한 최근 들어 어선이나 예선 등 소형선도 AIS(선박자동식별장치)를 설치하면서 관제대상 선박은 날이 갈수록 증가하는 추세이다. 따라서 선박이 항만으로 진입하기 이전 단계에 해양사고의 위험을 예방하기 위하여 항만관제의 범위가 확대되어야 한다는 필요성이 제기되고 있으며, 이로 인한 관제사의 업무량 및 스트레스도 증가하는 실정이다. 그러나 현재 사용중인 관제시스템은 모두 외국 제품으로 관제사의 다양한 요구사항을 반영하기에는 어려움이 있으며, 여러 기종이 혼재해 있어 VTS 간 연계도 불가능한 실정이다. 본 연구에서는 관제장비를 통합 연동하여 관제사의 업무량을 효과적으로 감소시키고 전국 VTS 및 관련 기관 업체와 상호 유기적으로 연계할 수 있는 맞춤형 관제지원시스템의 개발에 대한 필요성 및 개념, 주요기능, 활용방안 등을 모색하여 보았다.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2016.05a
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• pp.85-87
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• 2016

기존의 내연기관만을 이용한 선박 추진시스템은 내연기관의 저부하 운전 구간에서 효율이 낮아지는 문제점을 해결하지 못하고 있다. 그러나 최근 내연기관의 효율이 낮은 저부하 운전 구간에서 전동기를 기동함으로써 연료 효율을 높일 수 있는 하이브리드 추진시스템이 적용되고 있고, 이는 소형 어선부터 호화 여객선, 요트 등에 탑재되어 연료 절감 효과를 입증하고 있다. 본 연구에서는 하이브리드 추진시스템의 연료 절감 효과를 검증하고, 연료 효율을 높이기 위한 하이브리드 추진시스템을 제안한다.

• Journal of Power System Engineering
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• v.16 no.6
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• pp.24-29
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• 2012

In this study, the numerical simulation has been performed to investigate the hydrodynamic evaluation between double plate steel rudder and newly designed foil type rudder for small fishing boat. The simulations are carried out in 2 speed ranges with 7 variations of flow's angle of attack which is at intervals of about 5 degree respectively. As the well-known commercial code, FLUENT and CATIA are used as the solver. The simulation results show that new designed foil type rudder is better than conventional double plate rudder in terms of Lift and Drag of running boat in the water.

• Journal of Advanced Marine Engineering and Technology
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• v.25 no.6
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• pp.1324-1329
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• 2001

The depression of the external situation like the departure of WTO system and the plan of EEZ proclaim is forcing fishery into improving their fishing condition. By this international and domestic circumstance, development of the sea water cooling apparatus for fish hold storage is demanded sincerely. This study represents the thermal characteristics of the fish hold storage during transportation. The numerical analysis in this study is the finite volume method with the SIMPLE computational algorithm to study the seawater flow behavior in the fish hold storage. The computation were carried out with the variations of the circulating flow velocity and depth of fish hold storage. As the result of the three dimensional simulations, the mean temperature doesn't almost change by the circulating flow rate. find the mean temperature is suddenly changed by the ratio of depth of fish hold storage.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.44 no.1
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• pp.68-74
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• 2008

This study is concerned with the development of the basic planing hull form of small fishing boat in 25 knots high speed. A series of model test to determine the optimum performance hull form of actual fishing boat with 10 gross tonnage was carried out for 5 models made available planing hull form in the circulation water channel. Model test was performed with the resistance test to study the hydrodynamic characteristics of model ships and the sinkage and trim measurement to investigate the stability of model ships and also the wave pattern observation to analyze the effectiveness of model ships. As the result, the planing hull form of P-4 with deep V type bow can be derived as the best hull form with good performance especially in ship's resistance efficiency showing less residual resistance and sinkage and trim and the spray effect, etc..