• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.41 no.1
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• pp.70-77
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• 2005

The study was results obtained from the trial make of the hybrid GPS-electromagnetic(EM) compass which overcome shortcoming of GPS compass and EM compass. The results were summarized as follows: GPS compass detected the stable ship's heading at 0.1^{\circ}$ intervals with the turning angular velocity of less than 25^{\circ}$/sec in the experiment for the characteristics of turning angular velocity with stepmotor, but in case of over 25^{\circ}$/sec the compass did not detect it. On the contrary, the EM compass always indicated the ship's heading with no connection of the turning angular velocity, however the compass is low accuracy compared with GPS one owing to a compass error. The ship's headings by the hybrid GPS-EM compass were displayed at fixed point and moving by car; if the GPS compass work the headings were displayed by GPS compass, if not, the heading is provided stably by adding or subtracting of a compass error to the heading of EM compass. Also, each ship's heading was derived from not only the GPS compass but also the EM one by add or subtract of the compass errors, and then was worked covariance for the analogy. The results show that the ship's heading of two compasses has been verified the similarity to 95% confidence level.

• Journal of Fisheries and Marine Sciences Education
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• v.8 no.2
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• pp.199-205
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• 1996

실험에 사용된 5.18 G/T의 FRP선(올림픽24호)이 구성하고 있는 선체내 철물 구조로 인하여 발생된 자차는 매우 적게 나타났다. 그러나 자기 컴퍼스 주위에 방치되어 있는 연철봉 및 연철구의 영향으로 발생된 자차는 크게 나타났다. 그 결과를 요약하면 다음과 같다. 1) 선체내 철물구조로 인한 최대자차는 선수방위 N과 SW에서 $0.8^{\circ}$, SE와 W에서 $-0.7^{\circ}$였다. 2) Magnetic Compass주위에 방치되어 있는 연철구 또는 연철봉으로 인한 최대자차는 선수방위 NW에서 $6.0^{\circ}$ 및 NE에서 $-0.5^{\circ}$였다. 3) 연철구로 인한 영향은 선수가 4우점에 접근할수록 자차는 증가하였다.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2014.10a
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• pp.21-22
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• 2014

VDR은 IMO의 협약에 따라 요구되는 모든 선박의 데이터를 기록하는 장비이다. 2002년 7월 1일 이후 건조되는여객선과 3,000톤 이상의 여객선을 제외한 모든 선박을 VDR를 탑재하여야 한다. 이것은 항공기의 블랙박스와 같이 사고조사를 가능하게 한다. 이 논문에서는 VDR을 이용한 선박의 거동 특성에 대하여 실선 M/S WS 선박을 대상으로 실시하기로 한다. 이 선박은 2014년 1월 여천에 있는 GS 칼텍스 터미널 부두와 충돌하여 상당량의 기름을 유출시킨 바 있다. 이 논문에서는 어느 쪽 타각을 더 많이 사용하였는지를 알기 위하기 위하여 타각면적을 도입하였다 그 외에 평균 선수방위, 평균속력, 평균 rpm 등을 사용하였다. 이 결과 이 선박은 우현타각을 많이 사용하는 것으로 나타났고 이것은 이 선박이 좌선회하는 경향이 있음을 확인할 수 있다.

• Journal of Navigation and Port Research
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• v.41 no.4
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• pp.189-194
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• 2017

The Moving Search Radar System (MSRS) monitors sea areas by moving along the coast. Since the radar is initially aligned to the front of the vehicle, it is important to know the changes in the heading azimuth of the vehicle to quickly acquire the target azimuth from the radar after the MSRS has moved. The heading azimuth can be obtained using the gyro compass, the GPS compass or the electronic compass. The electronic compass is suitable for MSRS requiring fast maneuverability due to its small volume, short stabilization time and low price. However, using a geomagnetic sensor may result in an error due to the surrounding magnetic field. Errors can make early automatic tracking of the satellites difficult and can reduce the radar detection accuracy. Therefore, this paper proposes a method to automatically compensate for the error reflecting the correction value on the radar obtained by comparing the reference azimuth calculated by solving the geodesic inverse problem using two coordinates between the radar and the geostationary satellite with the actually-directed azimuth angle of the satellite antenna. The feasibility and convenience of the proposed method were verified by applying it to the MSRS in the field.

• Journal of the Korean Society of Marine Environment & Safety
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• v.15 no.4
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• pp.363-367
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• 2009

The ship maneuverability is changed by the effects of the bank cushion and the squat in the restricted water area. It is difficult to test the ship maneuverability by the real ship in the restricted water area because of ship's safety. In this study, a numerical model ship was used to simulate the ship's motion and to get information about the bank cushion and the squat in the restricted water area. The less apart from the quay the ship ran, the more ship's heading changed. The greatest change of ship's heading was $22.37^{\circ}$ when a ratio of the length between ship and quay to ship's breadh(=D/B) was 0.2. The squat of the ship was greater in shallower water and at faster speed. The greatest squat was 0.29m when a ratio of water depth to ship's draft(H/d) was 1.25 and ship's speed was 8 knots, the reduced speed was found to be the most important factor in the shallow water area for safety of the ship.

• Journal of Navigation and Port Research
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• v.33 no.8
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• pp.505-511
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• 2009

Vessels on anchoring are frequently dragged due to the increased area of wind pressure by enlargement of ship's size and sudden gust of winds in recent years. In the view point of the ship's navigators, the proper measurements corresponding to the dragging of anchor should be taken into account concerned about the time for the occurring of dragging by the external forces such as wind and wave, the pattern and speed of dragging and the possibility of collisions with any other vessels or obstacles. In this paper, it was examined the actual dragging anchor in T.S. HANBADA due to the wind and waves. From this case, it was found the critical external forces by which she was begun to dragged comparing the force by the wind, frictional resistance, drifting force and ship motion moment with the holding power. Also, through the analysis of the dragging pattern, it was known the alteration range of heading angle, swinging width and dragging speed etc.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2013.10a
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• pp.48-50
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• 2013

해상에서의 선박충돌사고 예방에 대한 연구가 IMO를 중심으로 꾸준히 지속되어 왔다. 이러한 항해장비 중에서 AIS는 중요한 역할을 수행하여 왔다. AIS 장비를 통하여 전송되는 정보에는 정적 정보와 동적 정보 및 항해 관련 정보로 구분할 수 있다. 정적 정보에는 MMSI, 선명, 호출부호, IMO번호, 선박길이 및 선폭, 선종 등 선박이 이동해도 변하지 않는 정보로 구성되고, 동적 정보에는 선박의 위치, 시간, 대지침로, 대지속력, 선수방위, 항행상태, ROT(Rate of Turn) 등 선박이 이동함에 따라 변화하는 정보로 구성된다. 그리고 항해 관련 정보에는 흘수, 위험화물, 목적지, ETA 등이 해당된다. 하지만, 이러한 정보들에 대한 활용도의 우선순위 및 정보의 적정성 등에 대해서는 아직까지 조사된 것이 없는 실정이다. 본 연구에서는 AIS 장비의 실 사용자를 대상으로 한 설문조사 및 분석을 통하여 AIS 송수신 정보들에 대한 활용도의 우선순위 및 정보의 적정성 등에 대해 검토해보고 필요시 개선 필요성을 제시하며 아울러 AIS 장비의 개선점도 검토해 보고자 한다.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2013.06a
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• pp.177-179
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• 2013

해상에서의 선박충돌사고 예방에 대한 연구가 IMO를 중심으로 꾸준히 지속되어 왔다. 이러한 항해장비 중에서 AIS는 중요한 역할을 수행하여 왔다. AIS 장비를 통하여 전송되는 정보에는 정적 정보와 동적 정보 및 항해 관련 정보로 구분할 수 있다. 정적 정보에는 MMSI, 선명, 호출부호, IMO번호, 선박길이 및 선폭, 선종 등 선박이 이동해도 변하지 않는 정보로 구성되고, 동적 정보에는 선박의 위치, 시간, 대지침로, 대지속력, 선수방위, 항행상태, ROT(Rate of Turn) 등 선박이 이동함에 따라 변화하는 정보로 구성된다. 그리고 항해 관련 정보에는 흘수, 위험화물, 목적지, ETA 등이 해당된다. 하지만, 이러한 정보들에 대한 활용도의 우선순위 및 정보의 적정성 등에 대해서는 아직까지 조사된 것이 없는 실정이다. 따라서 AIS 송수신 정보 상황을 분석해 관련 사항을 검토 할 수 있는 방안을 제시 및 향후 연구 수행 사항을 언급하고자 한다

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.05a
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• pp.181-184
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• 2016

This study is to compensate for inaccuracies in accordance with the change in the deviation correction value due to the movement and location of the ship cargo, equipment of the vessel, and eliminating the inconvenience of hand. By modifying the deviation through the simplification and automation was planned for accuracy and ease of modification of the modified value. The main method used is charted by measuring 24 direction and inputting the value of magnetic compass direction in automatic deviation-correcting apparatus manually or automaticallyThe measured values are exhibited in Table data and made it possible to calculate accurate correction value deviation. From this it can make deviation table having the margin of error within ${\pm}3^{\circ}$in all regions of the world And this table will help to navigational safety and economy under the unavailable or limited gyro contion.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.35 no.1
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• pp.11-18
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• 1999

In order to secure accuracy and effectiveness of the electromagnetic compass as information sensor for ship's head up bearing with gyro compass, magnetic compass and electromagnetic compass on the sea and on the dock in land.The results obtained were as follows;1. Between the Northeast and the southsouthwest the deviation on ship's head up bearing on electromagnetic compass got easterly deviation with max. $53^{\cire}$on the East and between the Southwest and the Northnortheast westerly deviation with max. $34^{\cire}$ on the Northwest, of which values were not able to be corrected due to the angle excess of deviation adjustment.2. The varies of deviation seemed to have a tendency to increase easterly deviation on the Northeast and the East, easterly deviation after westerly deviation between the South and the Northwest, small one on the North and the Southeast.3. The varies of deviation of ship were larger than the one of around the dock, were extreme on the bow of forecastle deck and were stable on the ship's center line of compass deck at the dock in land.