• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.1A
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• pp.1-9
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• 2006

An analysis of the annual frequency of collapse(AF) is performed for each bridge pier exposed to ship collision. From this analysis, the impact lateral resistance can be determined for each pier. The bridge pier impact resistance is selected using a probability-based analysis procedure in which the predicted annual frequency of bridge collapse, AF, from the ship collision risk assessment is compared to an acceptance criterion. The analysis procedure is an iterative process in which a trial impact resistance is selected for a bridge component and a computed AF is compared to the acceptance criterion, and revisions to the analysis variables are made as necessary to achieve compliance. The distribution of the AF acceptance criterion among the exposed piers is generally based on the designer's judgment. In this study, the acceptance criterion is allocated to each pier using allocation weights based on the previous predictions. To determine the design impact lateral resistance of bridge components such pylon and pier, the numerical analysis is performed iteratively with the analysis variable of impact resistance ratio of pylon to pier. The design impact lateral resistance can vary greatly among the components of the same bridge, depending upon the waterway geometry, available water depth, bridge geometry, and vessel traffic characteristics. More researches on the allocation model of AF and the determination of impact resistance are required.

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

• Journal of the Korean Institute of Intelligent Systems
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• v.24 no.6
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• pp.603-608
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• 2014

In the maritime traffic environment, the near-miss between vessels is the situation approaching on collision course but collision accident is not occurred. In this study, in order to calculate the near-miss between navigating vessels, the discriminating equation using ship bumper theory and vessel position clustering methods are proposed. Applying proposed module to the vessel trajectories of the WANDO waterway, we assessment navigational risk factors of vessel type, navigational speed, meeting situation.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.1
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• pp.67-73
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• 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 Fisheries and Marine Sciences Education
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• v.26 no.3
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• pp.647-655
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• 2014

In this research, unlike other fishing, the diving apparatus fishery is that the diver is engaged in fishing for profits. Because it is unique fishery, conflicts can be occurred in members. So, the purpose of this research is to define the contractual relationship between the parties of the diving apparatus fishery. For example, the relationship between the owner and diver and the owner and fishing ship crew. In addition, civil liability of default on the obligation was reviewed. Also, because the trouble was occurred by illegal fishing, criminal liability of ship crash caused by illegal diving apparatus fishery was considered. As a result, It is important to notifying the necessity of some method for the status of diver and fishing ship crew in diving apparatus fishery. moreover, It is need to educate the risk of illegal fishery for the parties of diving apparatus fishery.

• Journal of the Korean Society of Marine Environment & Safety
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• v.25 no.3
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• pp.313-319
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• 2019

As vessels become larger and competition between ports intensifies, there has been an increase in the number of cases where vessels that exceed the available berths are berthed at the pier. Therefore, there has been an increase in the number of cases in which the bow or stern of a ship is projected and moored. The risk of overhanging berthing is that mooring safety can be compromised because it is not possible to connect the bow and stern mooring line to the ship properly. In addition, collision accidents may occur between moving vessels if the view of a vessel moving in the port is obstructed. Therefore, in this study, the simulation of mooring safety was performed according to the overhanging range in Piers No. 6 and 7 in Ulsan's main port to propose the overhanging limit and operational standards according to each ship. As a result of the assessment, 30,000 DWT bulkers are able to overhang up to 0.75B, and 50,000 DWT bulkers can overhang up to 0.50B. The results of this study are expected to be used as basic data for setting the allowable overhang limit, as well as clear usage criteria for safe unloading operations.

• Ocean Systems Engineering
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• v.10 no.4
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• pp.415-434
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• 2020

Detecting objects is important for the safe operation of ships, and enables collision avoidance, risk detection, and autonomous sailing. This study proposes a ship detection method from images and videos taken at sea using one of the state-of-the-art deep neural network-based object detection algorithms. A deep learning model is trained using a public maritime dataset, and results show it can detect all types of floating objects and classify them into ten specific classes that include a ship, speedboat, and buoy. The proposed deep learning model is compared to a universal trained model that detects and classifies objects into general classes, such as a person, dog, car, and boat, and results show that the proposed model outperforms the other in the detection of maritime objects. Different deep neural network structures are then compared to obtain the best detection performance. The proposed model also shows a real-time detection speed of approximately 30 frames per second. Hence, it is expected that the proposed model can be used to detect maritime objects and reduce risks while at sea.

• Journal of Navigation and Port Research
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• v.34 no.10
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• pp.833-838
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• 2010

The Supreme Court in Korea judged the conduct of vessels in narrow channel was applied in order to prevent a ship collision in narrow channel, regardless of kind of a ship or weather situation, as application was not excluded as vessel restricted in her ability to manoeuvre without other special circumstances such as receiving the right of keep her course and speed from the other vessel, any priority was not guaranteed for vessel restricted in her ability to manoeuvre in regard to the other vessel following the conduct of vessel in narrow channel. In this judgement, there is concern to cause disorder to interpretation in the rule of narrow channel and responsibility between vessels. Therefore, this study aims to suggest correct interpretation about the rule concerned.

• Journal of Navigation and Port Research
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• v.35 no.3
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• pp.205-211
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• 2011

As the increase in maritime traffic and leisure, the marine accident risk has increased in the domestic coast. In this study, the cause and the environment of domestic marine accidents from 1990 to 2009 have been investigated and analyzed by using the statistics issues of Korean Maritime Safety Tribunal. Based on the analysis of most domestic marine accidents such as engine damage, collision, capsizing of small vessels, we propose how to use mobile telecommunication terminals for preventing marine accidents and the best countermeasures.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2013.10a
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• pp.167-170
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• 2013

The objective of this paper is to describe the result of development of collision avoidance supporting system, based on the electronic chart display and information system(ECDIS). In real ship operations, collision accidents happen frequently due to human errors such as the lax vigilance, misinterpretation of international regulations for preventing collisions at sea (COLREGs). We developed a system which will help to avoid these kind of accidents. This system can automatically recognize the risk of collisions, generate the safe alternative routes that comply with COLREGs, and then deliver the results into auto pilot. A virtual simulation assuming progressive collision situations revealed the usefulness of this system.