• Journal of Fisheries and Marine Sciences Education
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• v.23 no.3
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• pp.351-360
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• 2011

In order to reduce the casualties of fishing boats, the author analyzed the fishing boat accident on the 412 cases in Korean maritime safety tribunal for the 2005~2009, and then studied the relation between the weather element and the accidents. According to this studies, the occurring ratio of sea casualty for fishing boat in fog weather was appeared 1 boat per 1.6 days. It means that the restricted visibility condition gives the most influence on the fishing boat accident. The casualties in winter season from November to next January occurred 139(33.7%), and small boats less than 50tons broke out more casualties with 68.4%. From this we can find that small fishing boats are very deeply affected on the sea weather condition. According to the boat types for fishing the casualty of jig boat was ranked first, and collision accident account for first with 77.9% for the types of casualties. As mentioned above, most sea casualties for small fishing boats were resulted from the human factors such as poor watch keeping in invisibility and the bad sea condition, it is necessary for navigation operators and the manager to take more attention to the meteorological factors.

• Journal of Navigation and Port Research
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• v.44 no.3
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• pp.166-173
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• 2020

AtoN Accident causes navigation dangerous to ships and reduces the credibility of aids to navigation. The most light buoys on the sea have the highest accident rate from the influence of sea weather such as wind, current, and waves. However, in Korea, despite the different sea weather conditions in each sea area, in calculating the dynamic stability of the light buoy, there is a problem that only limit value conditions are applied to all sea areas. Thus, the purpose of this study was to analyze the dynamic stability of the LL-26(M) light buoy, the most installed buoy of its kind on the sea and suggest a stable operation plan for the LL-26(M) light buoy. To achieve this, after analyzing the weather for each sea area of the previous study related to the light buoy, the dynamic stability (inclination angle) was estimated by applying to the representative light buoys of each sea area wherein the number of accidents caused by sea weather was high. As a result of this study, the inclination angle of LL-26(M) light buoy for each sea area was different. That is, the inclination angle caused by winds was 10.329°-36.868°, the inclination angle caused by currents was 0.123°-18.834° and the inclination angle caused by waves was 4.777°-20.695°. The results of study can be used as basic data useful for installation standards for each sea area for stable operation of the LL-26(M) light buoy.

• Journal of Advanced Marine Engineering and Technology
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• v.33 no.5
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• pp.705-712
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• 2009

The state changes of ocean covered over 70% of earth surface are one of the greatest factor of weather catastrophe. Recently weather extraordinary events are followed by steep increase of sea water temperature and scientists in various fields are studying and warning the weather changes. In this paper, floating buoy is developed to monitor ocean environments via Orbcomm satellite and a method is proposed to increase measurement accuracy of sea water temperature with common low price temperature sensor. Experimental results are presented to illustrate the usability and effectiveness of the developed system. A web-based real time monitoring system is built to monitor ocean environmental information such as sea and air temperature, salinity according to the position of buoy through the internet for user convenience.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2018.11a
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• pp.241-247
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• 2018

Deep-sea fishing vessel No. 501 Oryong was fully flooded through its openings and sunk to the bottom of the sea due to the very rough sea weather on the way of evasion after a fishing operation in the Bearing Sea. As a result, many crew members died and/or were missing. In this study, a full-scale ship flooding and sinking simulation was conducted, and the sinking process was analyzed for the precise and scientific investigation of the sinking accident using a highly advanced Modeling & Simulation (M&S) system of the Fluid-Structure Interaction (FSI) analysis technique. To objectively secure the weather and sea states during the sinking accident in the Bering Sea, time-based wind and wave simulation at the region of the sinking accident was conducted and analyzed, and the weather and sea states were realized by simulating the irregular strong wave and wind spectrums. Simulation scenarios were developed and full-scale ship and fluid (air & seawater) modeling was performed for the flooding sinking simulation, by investigating the hull form, structural arrangement & weight distribution, and exterior inflow openings and interior flooding paths through its drawings, and by estimating the main tank capacities and their loading status. It was confirmed that the flooding and sinking accident was slightly different from a general capsize and sinking accident according to the simple loss of stability.

• Proceedings of KOSOMES biannual meeting
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• 2003.05a
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• pp.31-40
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• 2003

There are winds and waves in the sea, and they are changed frequently in accordance with the weather. By analyzing them which have the closest relation to the ship's safe voyage. evaluating the seakeeping performance and then taking a proper action, navigators should carry out safe navigation on the sea. A ship in seaways suffers continuous disturbances by irregular waves, and ship motions with irregular waves cannot be easily described as a system model which is adequate to a control system. But, in general, for seakeeping analysis, ship motions in irregular seas can be estimated by the superposition of the motion responses in regular wave components of the sea spectrum. After comparing and analyzing the winds and waves in major sea areas, this paper evaluates the navigational safety of ships on the Korean coast with potential dangerous seakeeping performance using the weather information provided by land. The conclusion is as follows : (1) It is possible that the safety of ships could be secured more accurately by evaluating the seakeeping performance of ships. (2) When the weather is bad, the departure of ships could be controlled by evaluating the navigational safety of ships. (3) When a ship is placed in commission in any area, this evaluation could be used to decide the type and size of ship in use.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2009.06a
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• pp.449-451
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• 2009

Sea level rise and increase of the typhoon/hurricane intensity due to global warming have threaten coastal areas for residential and industrial and have been widely studied. In this study we showed our recent efforts on sea wind which is one of critical factors for safe maritime traffic and prediction for storm surges and waves. Currently, most of numerical weather models in korea do not have sufficient spatial and temporal resolutions, therefore we set up a find grid(about 9km) sea wind prediction system that predicts every 12 hours for three day using Weather Research and Forecasting(WRF). This system covers adjacent seas around korean peninsula Comparisons of two observed data, Ieodo Ocean Research station(IORS) and Yellow Sea Buoy(YSB), showed reasonable agreements and by data assimilation we will improve better accurate sea winds in near future.

• Journal of the Korean Institute of Navigation
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• v.14 no.2
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• pp.33-59
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• 1990

In cold season, the developed extratropical cyclones and associated cold fronts, and NW winter monsoon are encountered very frequently in the North Pacific, especially in the northwest part of it. The two sea areas, namely, the northwest part of North Pacific, especially the eastern area far off Japan east coast, and Burmuda Triangle in the North Atlantic are generally known as two of the most dangerous areas in the world because of high incidence of sea casualties. Even large ocean going vessels were sunk frequently due to strong winds and very high seas caused by NW monsoon or developed cyclones during the winter months. The purpose of this paper is to analyse the real state of heavy weather and high sea phenomena on the vesscls at sea, thus helping mariners operate in such conditions.

• Journal of Ocean Engineering and Technology
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• v.17 no.2
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• pp.67-71
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• 2003

Using motions (Maruo) and wave reflection (the author), speed loss due to wind (van Berlekom) and ITTC standard spectrum, and various effects of weather(:such as weather intensity, ship type, ship size and draught) on ship speed performance at sea were investigated. Further, a comparison of the relative effects of weather and hull roughness on speed loss was also studied for a VLCC.

• Journal of Environmental Science International
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• v.25 no.6
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• pp.853-864
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• 2016

Meteo-tsunamis are tsunamis that are typically caused by strong atmospheric instability (e.g., pressure jumps) in low pressure systems, but some meteo-tsunamis in winter can be caused by local atmospheric instability in high pressure systems (e.g., the Siberian High). In this study, we investigated a meteo-tsunami event related to a high pressure system that occurred during winter on the Yellow Sea in 2005. Sea level data from tidal stations were analyed with a high-pass filter, and we also performed synoptic weather analyses by using various synoptic weather data (e.g., surface weather charts) collected during the winter season(DJF) of 2005. A numerical weather model (WRF) was used to analyze the atmospheric instability on the day of the selected event (21 Dec. 2005). On the basis of the results, we suggest that the meteo-tsunami triggered by the high pressure system occurred because of dynamic atmospheric instability induced by the expansion and contraction of the Siberian High.

• Journal of the Korean Society of Marine Environment & Safety
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• v.9 no.1
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• pp.41-50
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• 2003

There are winds and waves in the sea, and they are changed frequently in accordance with the weather. By analyzing then which have the closest relation to the ship's safe voyage, evaluating the seakeeping performance and then taking a proper act on, navigators should carry out safe navigation on the sea A ship in seaways suffers continuous disturbances by irregular waves, and ship motions with irregular waves cannot be easily described as a system model which is adequate to a control system. But, in general, for seakeeping analysis, ship motions in irregular seas can be estimated by the superposition of the motion responses in regular wave components of the sea spectrum. After comparing and analyzing the winds and waves in major sea areas, this paper evaluates the navigational safety of ships on the Korean coast with potential dangerous seakeeping performance using the weather information provided by land The conclusion is as follows: (1) It is possible that the safety of ships could be secured more accurately by evaluating the seakeeping performance of ships. (2) When the weather is bad, the departure of ships could be controlled by evaluating the navigational safety of ships. (3) When a ship is placed in commission in any area, this evaluation could be used to decide the type and size of ship in use.