• KEPCO Journal on Electric Power and Energy
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• v.6 no.2
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• pp.163-171
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• 2020

A model test for assessment of towing stability and seakeeping of a multi-purpose mobile base (MMB) was performed in calm water and wave conditions. Scale ratio of the MMB was 1/48. Tension of the towing line was measured during tests to estimate effective power to tow the full scale MMB. The tests were repeated with towing speed. In addition, an inertial measurement unit was used to measure six DOF motion of the model. Seakeeping performance was assessed through the captive model test.

• Journal of Navigation and Port Research
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• v.31 no.10
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• pp.905-910
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• 2007

As the ship is getting bigger and faster lately, ship's structure or cargoes might be often damaged and the ship might be cut in two in extreme conditions by a wave impact on its bow. In this paper, the vertical acceleration, which is one of factors for evaluating seakeeping performance, was measured under the various sea states by the hull stress monitoring system(HMS) on the bridge, and the result was compared with those of model test and theoretical studies. Then, we confirmed the seakeeping performance of T.S. HANBADA by comparing it with ITTC seakeeping criteria This result will be a great help for the safe navigation by making it possible to estimate the possibility of work and the amount of risk under the various sea conditions with which may be confronted, and the shipbuilding yard can be possible to construct the vessel with superior performance through these data measured on the actual ship.

• Journal of the Society of Naval Architects of Korea
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• v.36 no.4
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• pp.56-63
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• 1999

The seakeeping and resistance tests of a 47.7m class catamaran are conducted in a towing tank with the 1/21.5 scale model. The effect of the trim tab on the resistance is investigated with the trim tab angle variations and the resistance and trim angle of the catamaran with the trim tab are compared with those without the trim tab. The heave and pitch motions are measured at the three full scale speeds in sea state of 3.4 and 5 and the vertical accelerations at five points on the deck are also measured. The measured accelerations are compared with the criteria of ISO 2631/3 and it is shown that the seakeeping performance of the catamaran is good.

• Journal of the Korean Institute of Intelligent Systems
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• v.22 no.3
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• pp.379-385
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• 2012

This paper developes the navigation visual aid supporting a watch officer's situation awareness and analyzes its performance test result. Developing the equipment made from composite video sensor which transfer video signal, ranger laser measurement model which search out distance, Pan/ Tilt, center control device. The developed equipment with Pan/Tilt was made from high performance video sensor and ranger laser measurement. To make a real ship test, we carried on setting the developed equipment on ship, observed a danger factor and analyzed a image, and from that we can evaluate marine environment awareness. Through this result, the developed equipment can show effective ability of the awareness of the clearer check and resolution situation when compare with the binocular.

• Journal of Fisheries and Marine Sciences Education
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• v.21 no.1
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• pp.52-58
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• 2009

With the increase of marine traffic capacity, marine accidents have also been increased for recent several years. Especially watch officer must maneuver not entering into the safety minimum approaching distances when two power-driven vessels are crossing. The author calculated the safety minimum approaching distances to provide a navigator with them based on zig-zag motion by experimental ship. The obtained results are summarized as follows : 1. The greatest distance is to be kept by the give way vessel to avoid collision when the crossing course angle is $90^{\circ}$. In this case the safety minimum approaching distance must be more than from 5 times to 11 times of her own length according to her size. 2. The watch officer of the give way vessel must always take an action to avoid collisions outside of the safety minimum approaching distance. 3. When the navigator used rudder to small angle than to large angle to avoid other vessel he must take action outside the sufficient safety minimum outside distances in advance. 4. Risk of collision in crossing situation is more greater in obtuse situation than in acute one.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.19 no.2
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• pp.99-105
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• 1983

In the Steering and Sailing Rules of International Regulations for Preventing Collicions at Sea, 1972, any relative distance between two vessels necessary for taking action to avoid collision in head-on situation is not referred. In this paper, the author analyzed the ship's collision avoiding actions from a viewpoint of ship motions and worked out mathematical formulas to calculate the relative distances necessary for collision avoiding actions. Figuring out the values of maneuvering indices through experiments of actual ships, the author applied these values to the calculationg formulas and calculated the minimum safe relative distances. On the assumption that two vessels same in size and condition are approaching each other in head-on situation, the minimum safe relative distance was calculated as 5.0 times, sufficient safe relative one as 10.0 times their own length.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.4
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• pp.15-24
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• 2019

The optimum solutions of MOSCOS antenna arrangement were studied to solve the EMI between it and EWT mounted on an MTB. Two candidates of optimal place for MOSCOS antenna were determined by using a fishbone diagram to determine seven reasons based on 4M1E, to identify the design factors on Friis equations, and to analyze the case study of EMI related to MOSCOS. MOSCOS antenna was rearranged by the final optimal position, which was selected by measuring the Power Spectral Density (PSD) at two locations, and the proposed improvement was tested on board to determine its efficiency.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2019.05a
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• pp.121-122
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• 2019

차도선과 같은 연안 화물 여객선에는 필수 탑재 항해통신장비 이외에 유지보수 지원이나 운항 효율 향상을 위한 장비는 거의 탑재 되어 있지 않은 상황으로 ICT 기술 기반 운영 및 유지보수(O&M, operating and maintenance) 지원 서비스 제공 시스템 도입이 필요하다. 이에 중소형 선박 기자재의 데이터 수집, 통합, 분석을 통해 선박 관리, 유지보수 지원, 운항 모니터링 등의 스마트 O&M 서비스를 제공하기 위한 시스템의 개발을 진행 중에 있다. 개발하는 시스템은 빅데이터 분석 기술, 모바일 어플리케이션 개발 기술, 증강현실(AR) 기술을 기반으로 선박을 구성하는 요소의 상태 모니터링, 최적 관리, 원격 유지보수 지원 등의 서비스를 제공할 예정이다. 또한, 클라우드 기반 육해상 통합 O&M 서비스 지원 시스템의 개발을 통해 선단 단위 분석, 중소형 해운선사 소모품 관리 및 운영 지원 등 종합적인 부가 서비스를 제공하는 것이 목적이다. 이러한 시스템의 개발이 완료되면, 실선 시험을 통해 개발 시스템과 서비스의 유용성을 검증할 계획이다. 본 논문에서는 이러한 O&M 지원을 위한 시스템에 관해 소개하고, 앞서 언급한 각종 서비스를 제공하기 위한 선박 및 육상 측 구성요소 정의와 서비스 아키텍처의 설계에 관한 내용을 다룬다.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.15 no.1
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• pp.87-94
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• 2016

Although studies and investments on electro-magnetic fields in terrestrial areas are being conducted, they are not applied to a ship. Especially ship is consist of Top Side, Bridge, and Engine Room. Top Side is mounted Antenna and radar. Bridge is mounted navigation and navigation equipment that have a safe voyage. Finally, Engine Room is mounted switchboard and this is used to ship propulsion system. Therefore the purpose of this paper is for suggesting optimized standard to apply to marine environment through analyzing electromagnetic wave environment in ship. For this, we were measured EMF in Hanbada ship in Korea Maritime and Ocean University and we compared and analyzed to measured values in Korea standards and international standards. Consequently, Engine Room of ship for the identified that there are limits to apply. The proposed results of this research will be expected to utilize for establishing standard a plan for EMF in ship.

• Journal of Navigation and Port Research
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• v.39 no.6
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• pp.465-472
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• 2015

SEEMP (Ship Energy Efficiency Management Plan) guidelines for a ship's GHG reduction include a machinery modification of hull, an installation of energy efficiency enhanced attachment in hardware methods. It is also possible to bring a ship energy efficiency improvement by fuel-efficient operations or in other software methods. Hardware modification or installation on ship can bring financial burdens to a ship company compared to its improvement expectation. On the other hand, Software based energy-saving technology can be applicable on various ship types, and it is also expected high efficiency of ship energy use compared to hardware based technology in perspective of the investment costs and efficiency. In this paper, it is described that the ship handling simulator based evaluation was carried out using representative ship model of bulk, container and VLCC. Simulation environments were separated into 6 conditions according to the sea-state and weather condition, and the operation results were compared with those before and after energy saving system applied The container ship showed the largest FOC save rate after energy saving system applied although the others also showed energy save rate after using the system.