• Journal of the Society of Naval Architects of Korea
• /
• v.46 no.6
• /
• pp.595-602
• /
• 2009

Great number of ships has been built by Korean Shipyards since early of 2,000 due to the expanding worldwide trade. Most of shipyards have enlarged the weight of erection block and many blocks have been assembled in block fabrication factories outside the shipyards to reduce the shipbuilding period. Especially, Giga blocks that exceed 2,000 tons are often assembled by the block fabrication factories outside the shipyard. Generally, the blocks are transported to building dock in shipyard by towing barges. Accident can be occurred during the sea transportation and it may bring about not only the delay of delivery but also a disaster on the ocean environments. Transportation condition of GPE (Grand Pre-Erection) block differs from the ocean going conditions of marine vessels. Special consideration should be included before transportation work in order to guarantee the safety of GPE blocks and barge carriers. In this paper, several examples, which have been investigated to set up the safety standard of transportation of the GPE blocks on coastal routes, are introduced. For the barge transportation on coastal sea route, the design criteria are discussed, considering the design wave, the acceleration induced by wave, structural strength, and the fixture condition of blocks.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.25 no.2
• /
• pp.151-158
• /
• 2019

Wireless communication technology (WAVE) for vehicles, which is the core technology behind the next-generation intelligent transport system (C-ITS), is used to deliver information about vehicles to prevent traffic accidents and traffic situations that may arise between vehicles and infrastructure. Similar traffic issues often arise in marine scenarios. Currently, AIS is being used as a means of transmitting information such as the status of relative vessels, but research is being carried out to solve problems with AIS such as overloading by applying wireless communication technology for vehicles to the sea. In this study, a collision warning system suitable for small-sized vessels was developed based on the marine application of WAVE for vehicles verified through prior research, and the adequacy of this collision warning system was reviewed through a practical test. It is expected that this system will contribute greatly to future e-Navigation applications or self-driving ships as well as to preventing marine accidents.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.29 no.2
• /
• pp.215-222
• /
• 2023

Alternative marine power (AMP) is continuously used in ports and on docks because of regulations on global ship emission reduction. In Korea, the use of AMP is also mandatory under the Special Act on Port Air Quality Improvement, and efforts are under way in connection with various eco-friendly ships, such as electric-propulsion ships. In this study, AC load flow analysis was performed by modeling the situation in which onboard power is supplied through AMP. This analysis made it possible to study the electrical parameters and losses when power was supplied to the ship. In addition, through a transient stability analysis, the high-speed generation transfer limit value for uninterruptible conversion through onboard generators in the event of a system accident was derived. The results obtained when it was applied are presented

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.26 no.1
• /
• pp.22-30
• /
• 2020

In March 2016, a 6.67-ton fishing boat capsized owing to the loss of stability during crane operations. Capsizing occurs when a boat or ship is flipped over (or turned upside down) for reason other than accidents caused by collisions, contact, stranding, fire or explosion. Over the past nine years (2010-2018), capsize accidents have accounted for 2.34 % of all marine accidents and are gradually increasing. The loss of stability from improper shipping is the main cause of most capsizes, especially for small fishing vessels weighing 10 tons. According to the Fishing Vessel Act, small fishing vessels weighing less than a ton are exempted from inspections on stability and load cranes. This study analyzes the issue cited as the reason for the capsizing of the small fishing boat in Goseong, namely, the reduction of restoring moment due to increased weight of the crane. Fishing boats with similar loading conditions were modeled on the basis of re-determination, and their stability before and after the accident was assumed. The fishing boats with heavier cranes were found to be at higher risk of capsizing owing to the reduction of the restoring moment and the angle of deck immersion. Under standard loading conditions, the stability moments of fishing vessels are lesser during fishing, compared to when they depart from or arrive at the port.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.22 no.7
• /
• pp.1021-1029
• /
• 2018

The marine buoys are operated in various domains, which are navigation route and danger maker, weather and environment monitoring, military strategical element, etc. If the marine buoy is damaged, there consumes many cost and time for recovery or replacement, because of severe environmental condition, and causes a risk possibility of secondary accident. In this paper, we developed an active monitoring and approach alarm providing system using trail cameras and AIS for protection for the marine buoys. To do this, we analyzed existing researches and similar systems, extracted requirements for enhancement, and designed the system architecture that applied the enhanced elements. The main considerations of system enhancement are: integration of AIS and trail cameras, adopting of phased alarm technique by approaching ships, applying of selective communication module, conducting the image processing of ships for providing alarm, and applying thermal cameras. After that, we developed the system using designed architecture and verified effectiveness of the system based on laboratory or field-level tests.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.28 no.4
• /
• pp.632-638
• /
• 2022

As Korean coastal activity is high, the incidence of accidents caused by marine waste is extensive. An accident in which marine floating waste ropes and fishing nets are wound around the propeller of a sailing ship is termed "Rope wrapped accident." To prevent such accidents, this study applied the Finite Element Method (F.E.M.) for performance evaluation of the shaver type cutter, commercialized in Korea, through a structural safety review and water tank test. The results demonstrate that all parts constituting the rope cutter were damaged before reaching 0.5s, and the safety factor of each part was found to be at least 2 based on the maximum stress generated compared to the tensile strength. In the basin test, the cutting process of the shaver type rope cutter was reviewed, and the installation angle was set for each case considering that the rope floating in the sea actually enters at various angles. Consequently, as it was successful at cutting in all the cases, it can be concluded that there will be no problem in cutting the rope regardless of the mounted angle of the cutting blade.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.27 no.7
• /
• pp.967-976
• /
• 2021

Over the last ten years, the number of entanglement marine accidents has increased more than other accident types. This study analyzed the annual statistical report of marine accidents from the Korea Maritime Safety Tribunal and Korea Coast Guard. Despite some discrepancies between data of the two organizations, it was found that marine accidents involving fishing vessels were more prevalent than those involving non-fishing vessels. In addition, the main floating materials that caused wounded entanglement accidents were fishing nets, fishing gear, and ropes, and the proportion of them was high. Foreign and domestic policies on marine plastics recognize most marine plastics as marine environmental hazards and focus on marine litter recovery and the prevention of marine pollution. The representative Acts related to the marine environment and marine litter, the Marine Environment Management Act and the Marine Waste and Sediments Management Act, recognize marine litter as a type of marine waste, and deal with the types and definition of this waste. However, clearly defining marine waste is difficult. Therefore, this study tried to examine the relevant legal system of marine litter on ship operation and suggested improvement measures. Moreover, the definition of marine litter for the safe navigation and operation of ships was clearly proposed.

• Journal of Navigation and Port Research
• /
• v.32 no.8
• /
• pp.569-576
• /
• 2008

By the development of international trade in last decades, Korean International Trade has been grown rapidly and Korean Port and Port facilities have been improved stimultaneously: finally volume of the marine traffic increased rapidly. Presently, 15 VTS centers have serving in Korean waters and since the introduction of the first VIS Center in Korea there is no quantitative analysis to find workload of VIS operator. After that Port-MIS and De-brief data have been gathered for 7 days and inbound-outbound vessels time-g/t table prepared and traffic volume examined for each V1S center. Hence $L^2$ conversion traffic volume and dangerous vessel ratio obtained Later on conversion controlled number obtained by denoting ratio 1.0 to directly controlled vessels by VTSO and denoting ratio 0.3 to indirectly controlled vessels by VTSO. Traffic volume, large vessel ratio, dangerous vessel ratio, dimension of VTS controlled area, marine accident occurrence frequency and communication volume of comm. log can be counted as a factor which influence to workload of VTSO. All those factors have been examined and analyzed. Finally, ship's size and dangerous vessel ratio have been chosen to derive the Number of composite conversion control for workload formula.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2019.05a
• /
• pp.230-231
• /
• 2019

This study is a development on condition based maintenance(CBM) technology which is a core item of future autonomous ships. It is developing to design & installation of condition monitoring system and acquisition & processing of data from ongoing ships for fault prediction & prognosis of engine in operation. The ultimate goal of this study is to develop a predicts and decision support software for marine engine faults. To do this, the FMEA and fault tree analysis of the main engine should be accompanied by the analysis of classification of system, identification of the components, the type of faults, and the cause and phenomenon of the failure. Finally, the CBM system solution software could predict and diagnose the failure of main engine through integrated analysis for bid-data of ongoing ships and engineering knowledge. Through this study, it is possible to pro-actively cope with abnormal signals of engine and to manage efficiently, and as a result, expected that marine accident and ship operation loss during navigation will be prevented in advance.

• Ocean and Polar Research
• /
• v.44 no.4
• /
• pp.355-364
• /
• 2022

When the 60-ton-class patrol boat '72' of the Korea Coast Guard (KCG) was on duty and she accidentally collided with another patrol boat ('207', 200-ton-class) and sank. A month-long search found a small amount of lost items, but neither the crew nor the ship was found. For the first time in 39 years since the accident, the Korea Institute of Ocean Science and Technology (KIOST) searched the boat 72 using the latest integrated geophysical techniques. A number of sonar images presumed to be of a sunken ship was acquired using a combined system of side scan sonar and marine magnetometer, operated at an altitude of approximately 30 m from the seabed. At the same time, a strong magnetic anomaly (100 nT) was detected in one place, indicating the presence of an iron ship. A video survey using a remotely operated underwater vehicle (ROV) confirmed the presence of a shielding part of a personal firearm at the stern of the sunken vessel. Based on these comprehensive data, the sunken vessel discovered in this exploration was assumed to be '72'. This result is meaningful in terms of future ocean exploration and underwater archaeology, as the integrated system of various geophysical methods is an efficient means of identifying objects present in the water.