• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• v.2
• /
• pp.9-11
• /
• 2006

우리나라에는 매년 평균 $2{\sim}3$회의 태풍이 내습하고 있다. 이러한 태풍의 내습시 우리나라 남해 근방의 항만에 정박증인 선박과 항행중인 선박의 대부분을 진해만으로 피항을 하고 있는 실정이다. 이러한 진해만 피항시 정박하고 있는 많은 선박들 사이로 정박지를 찾아 헤메는 선박들로 인하여 위험한 상황을 초래하고 있다. 이러한 정박지 선정을 레이더를 통하여 진해만 정박지를 사전에 결정할 수 있으면 좋으리라 판단된다. 이 연구는 현재 정박지에서 선박간의 최소거리를 진해만 태풍 내습시의 자료를 이용하여 모델화하고 이 모델을 통하여 선박간의 최소 정박지 거리제공으로 선박항자에게 신속하고 정확한 정박지 선정에 도움이 되고자 한다. 또한 VTS center에서 정박지를 사전에 지정하는데 도움이 되는 시스템을 구축하는 기초자료로 이용하고자 한다.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• v.2
• /
• pp.5-7
• /
• 2006

항행하는 선박은 자기선박 주변을 하나의 영역으로 생각하여 그 영역안에 타선박의 허가하지 않는 자기만의 영역을 가지고 있다. 지금까지 우리나라에서는 선박간의 항과거리를 일본의 자료를 이용하여 해상교통 환경평가의 하나인 해상교통혼잡도를 평가하고 있다. 이 일본의 자료는 30년전의 자료이며 선박의 고속화${\cdot}$대형화로 인하여 선박간 항과거리는 선박의 통항형태, 항로의 종류, 선박의 크기에 따라 상이할 것으로 사료된다. 하지만, 상기의 모든 요소를 다 가미하여 일반화한 연구는 찾아보기 힘들며 상당한 자료를 이용하여야 하므로 분석하는데 시간이 많이 걸릴 것으로 판단된다. 이 연구에서는 해상교통량이 대단히 높은 중국 상해항을 입출항하는 선박간의 항행거리를 기초로 선박간의 최소 항과거리를 모델화함으로써 우리나라 실정에 맞는 해상교통혼잡도 평가에 이용하고자 하며, 선박운항자들의 항행에 최소 항과거리를 제공함으로써 안전항행에 도움을 주고자 한다.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.16 no.4
• /
• pp.401-406
• /
• 2010

Vessel Operator has been navigating with subjective sate distance in accordance with night & daytime, fore & aft, port & stbd abeam and visibility situation. This sate distances may different depending on inside & outside harbor limit, current, wind and visibility situation. By now, the concept of proper sate distance between navigating vessels has been adopted in Korea, using the early 1980's foreign data. And the safe distance is being used with the same value without any consideration of inside & outside harbor and the kind of vessel. So it is necessary to evaluate or search proper distance concept based on different sate consciousness of Korean manners. This paper aims to develop the basic model for marine traffic evaluation and the new model of marine traffic congestion. Also this paper proposes the basic control guideline of vessel traffic service center. The result of this study showed that minimum sate distance should be 4.4L forward, 3.1L aft and 26L abeam in case of good visibility in daytime, considering various parameters such as visibility, day and night. Some differences Here found between the existing minimum sate distance and the new minimum sate distance derived from the result of this study.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2011.11a
• /
• pp.21-22
• /
• 2011

In this study, an analytical algorithm for collision avoidance is proposed, which is applicable to designing collision avoidance maneuvers for two encountering ships. The minimum separation distance is defined and an appropriate maneuver sequence is computed for safe and effective collision avoidance. Two approaches: 1) collision avoidance through speed change and 2) collision avoidance through heading change, are considered, and the initiation point of the avoidance maneuver is computed analytically using the geometric configuration of the two encountering ships. To verify the feasibility of the proposed algorithm, numerical simulations are carried out using a set of ship-to-ship encountering scenarios.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.29 no.4
• /
• pp.338-347
• /
• 2023

Jinhae Bay, characterized by frequent runaway ships and strong winds during typhoon attacks, poses a high risk of maritime accidents such as ship collisions and groundings. This study aims to determine a safe separation distance between ships in the Jinhae Bay anchorage, considering the unique environmental characteristics of the Korean sea area. Analysis revealed that an average of 100-200 ships anchor in the typhoon avoidance area in Jinhae Bay during typhoon attacks, with approximately 70% of ships experiencing anchor dragging owing to strong external forces exceeding 25 m/s wind speeds. In this study, we analyzed and presented the separation distances between ships during anchoring operations based on domestic and international design standards, separation distances between ships used as actual typhoon shelters in Jinhae Bay, and appropriate safe distances for ships drifting under strong external forces. The analysis indicated that considering the minimum criteria based on the design standards and emergency response time, a minimum safe distance of approximately 400-900 m was required. In cases where ample space was available, the separation distance was recommended to be set between 700 to 900 m. The findings of this study are anticipated to contribute to the development of guidelines for establishing safe separation distances between ships seeking refuge from typhoons in Jinhae Bay in the future.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.32 no.4
• /
• pp.363-371
• /
• 1996

The Steering and Sailing Rules of International Regulations for Preventing Collisions at Sea now in use direct the best aid - action to avoid collision by the stand - on vessel. But these rules do not refer to the safety relative distance between two vessels when she should take such action. In this paper, the author analyzed the ship's collision avoiding actions from the viewpoint of ship motions and worked out mathematical formulas to calculate the relative distances necessary for taking action to avoid collision. Figuring out the values of maneuvering indices through experiments of 11 actual ships of small, medium, large and mammoth size, the author applied these values to the calculating formulas and calculated the minimum relative distances. The main results are as follows: 1. It was confIrmed that the stand - on vessel should keep the greatest relative distance for taking best aid - action to avoid collision when the cross angle of course was $90^{\circ}$ and near it(70-$90^{\circ}$ ). 2. When the cross angle of course was $90^{\circ}$ , the minimum relative distance of small vessel(GT: 160-650tons) was found to be more than about 6.8 times of her own length, and those of medium(GT : 2,300-3,500tons), large(GT : 22,OOO-62,OOOtons) and mammoth(GT : 91,000-139,000tons) vessels were found to be more than about 9.0 times, about 5.4 times and about 6.8 times of their own lengths. 3. It was confIrmed that collision danger was greater when crossing angle was obtuse than in an acute angle, therefore greater relative distance was to be kept by the stand - on vessel for taking best aid - action to avoid collision in the case of the obtuse angle. 4. In every vessels, in the case of $90^{\circ}$ cross angle of course the safety minimum relative distance was found to be more than about 9.0 times of their own lengths.

• Journal of Navigation and Port Research
• /
• v.38 no.4
• /
• pp.327-333
• /
• 2014

The Convention on the international regulations for preventing collisions at sea, 1972(COLREGs) defines the collision avoidance principles and various navigation rules for the prevention of collision at sea. In particular, the initial responses to avoid risk of collision are mainly decided by navigation officer's experience and subjective judgement. However, collision accidents could be effectively prevented if the minimum criteria of quantitative initial response are suggested to the junior officers and the cadets who have insufficient sea experience and navigation competency. This study reviewed the COLREGs terms related to the initial response and the existing papers concerned with risk assessment model. A questionnaire survey is also carried out for safe passing distance, degrees of alternating course and initial response distance to avoid collision in accordance with various encounter situations. Base on these results, we propose the proper minimum safe passing distance between the vessels, the initial response distance and required turning angles for alternation in each encounter situations. The suggested criteria of initial response will contribute to the prevention of collision at sea as well as the improvement of gradual navigation technology.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2012.06a
• /
• pp.565-567
• /
• 2012

최근 목포 해상교통관제(VTS)구역 내 만곡부 항로상에 연륙교가 건설됨에 따라 연륙교를 통과하는 선박들의 충돌사고 위험성이 높아질 개연성이 커졌다. 해당 수역에서의 선박교차와 관련된 선박교통의 분석을 집중적으로 실시함으로써 향후 해상교통관제 업무와 관련하여 주의하여야 할 사항 및 대책들을 제시하였다. 특히 교차빈도가 높은 여객선과 예부선 간의 C PA를 분석함으로써 해상교통사고의 위험을 줄이기 위해 확보되어야 할 최소안전거리에 대해서 중점적으로 검토하였다.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.27 no.1
• /
• pp.67-73
• /
• 2021

The purpose of this study is to obtain a safe area for a passing vessel between anchored vessels by developing a model to predict the collision risk, frequent collisions occur between the anchored vessel and the passing vessel through the anchorage. For this, this study selected the southern anchorage of Busan port, which is the largest harbor in Korea, as the target area and extracted and analyzed VTS (Vessel Traffic Service) data during the period in which anchored vessels were the most waited. The ratio of D/L for each bearing was obtained to determine the safe distance (D) passes based on the length (L) of the passing vessel between anchored vessels. Based on the average domain of the D/L ratio distribution, the percentage of anchored vessels within the scope of the pre-studied ship's domain was analyzed to obtain a domain reflecting the degree of risk of VTSOs. Further research will evaluate and analyze the collision risk of a passing vessel using Domain-watch, the minimum safe distance between anchored vessels, and the safe domain of a passing vessel through anchorage, to develop a model for VTS to manage anchorages more efficiently and safely.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.24 no.7
• /
• pp.841-847
• /
• 2018

Since global energy consumption and demand for energy have dramatically risen, a focus on environmental problems and sustainability has become more important. Clean and renewable energy sources such as offshore wind power generation have received attention among new renewable energy options as alternative energy resources. Due to maintenance and operational perspectives, offshore wind farms have been planned for installation in many coastal waters. However, development of offshore wind farms faces interference from existing maritime traffic along the planned areas. In order to safely and effectively govern marine traffic in the vicinity of wind farms and inner areas, standard criteria are suggested to allow vessels to sail the internal waters of offshore wind farm areas. Therefore, the purpose of this study is to establish allowable criteria for sailing vessels and safety zones for offshore wind farms by investigating the local regulations of various offshore wind farm cases overseas. The commended inner safety zone of wind farms is proposed to be a distance of 150 % of the rotation diameter of the wind turbine rotor and a distance of 200 m from the outer wind turbine for the outer safety zone. Besides this, the allowable criteria for sailing vessels within a wind farm is proposed to have an air draft of 14.47 m south-west wind farm sea areas for a minimum margin to avoid hull contact through evaluation of the tide and height of a wind turbine. further studies will be needed to establish vessel sailing criteria among adjacent offshore wind farms as well as vessel sailing criteria within a single offshore wind farm.