• 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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• 2015.07a
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• pp.354-356
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• 2015

포항항 관제구역은 2009년 8월 영일만항 개장으로 방파제(길이 5.5km) 신설에 따라 정박지 'S-5'내 조류 및 저질변화로 인해 정박선의 주묘현상이 현저하게 발생하고 있으며, 포항 신항내 고층구조물 신설로 인해 동일 시간대 풍향 풍속등 기상현상이 포항구항 및 영일만항, 호미곶과는 달리 강력하게 발생하여 입 출항선박의 안전에 위험을 초래하고 있다. 이와 같이, 관제구역내 환경변화에 따른 정박선의 현저한 주묘 및 포항 신항내 강력한 풍향 풍속등의 발생이 선박의 안전을 위협하고 있다. 본 연구에서는 관제구역내 환경변화에 따른 해상교통안전의 위험을 줄이기 위한 VTS의 역할 및 대처방안에 대해 모색해 보고자 한다.

• Journal of the Korean Society of Marine Environment & Safety
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• v.15 no.1
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• pp.49-55
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• 2009

Typhoons are usually influencing at least 3 or 4 times per year in Korean peninsula and they accompanied with strong winds and heavy rains and then brought tremendous loss of properties and lives. Especially typhoon "MAEMI" resulted in a lot of marine accidents of vessels such as sinking, stranding, collision etc. at anchoring or on berthing in pier. If the typhoon comes up to expected area influencing the incidents, the vessel tries to escape from the route of typhoon or anchor in sheltering anchorage. However, consideration of the anchoring or judgement of ship's safety against strong winds is decided only by the experience of operators without detail evaluation of the safety. Therefore, this paper evaluated the safety of T.S. HANBADA by comparing the external forces with the holding powers. Furthermore, based on this evaluation, the anchoring manual was produced for the maximum endurable wind velocity, the general precautions and the actions taken on the ship with steps.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2014.10a
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• pp.5-6
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• 2014

Pohang port have specified 19 anchorage and 3 quarantine anchorage, but this anchorage is insufficient required anchorage because the average daily use of more than 40 vessels, also Pohang anchorage have geographical characteristics that are open to offshore northeast direction. Recently, sinking ship accident was caused at Pohang port anchorage by dredging anchor due to strong wind from north or north-east. ${\cdots}$ (중략) ${\cdots}$.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.4
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• pp.474-482
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• 2021

An average of two to three typhoons that occur in the Philippines or Taiwan pass through Korea each year owing to the influence of the geographical location and western winds. Because Jinhae Bay is known as Korea's representative typhoon refuge, it is filled with ships during typhoons and later becomes saturated with ships anchored to the surrounding routes. If a strong wind drags an anchored ship, a collision accident may occur because of the short distance between the ships. Therefore, a systematic anchoring safety management of Jinhae Bay is required. In this study, the minimum wind speeds of a dragging anchor based on the water depths of Jinhae Bay anchorages were investigated. When 7-9 shackles were given, the minimum wind speeds were 48-63, 46-61, and 39-54 knots at depths of 20, 35, and 50 m, respectively. As the water depth increased, the length of the cable laid on the sea bed became shorter than 5 m owing to the external force, and the minimum wind speed showed a significant difference of 4-8 knots. In addition, ships with high holding power anchors (AC-14 type) had higher minimum wind speeds than ships with conventional anchors (ASS type). Finally, it was confirmed that at a depth of 50 m, dragging easily occurred even when a high holding power anchor was applied.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.40 no.3
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• pp.225-231
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• 2004

The power and scale of 950 hPa typhoon "Maemi" which struck the shore of Gosung in Kyungnam Province was same as that of 951 hPa typhoon "Saraho" in 1959. For the purpose of getting the safety of training ship "KAYA", we anchored at Jinhae Bay with riding at two anchors paid out 8 shackles of cable respectively. By the way when wind force being over 30m/s, we could not keep the safety of the ship "KAYA" by means of the holding power of an anchor only. Just by using the main engine moderately, we were able to maintain the security of the ship. The holding the main engine moderately, we were able to maintain the security of the ship. The holding power of an anchor according to the way of anchoring, the quality of sea bottom, the direction and speed of wind and current, and the length of an anchor cable were analyzed. The obtained results are summarized as follows : 1. When riding at two anchors rather than lying at single anchor we could get a good holding power. 2. There was a big difference in holding power according to the quality of the bottom. 3. It would be best anchoring in a soft mud area than in any other place as possible. 4. It would also be desirable to set anchor shackles much more than equipment number prescribed in regulation in order to get safety of a ship providing against typhoon.