• Journal of Conservation Science
• /
• 제32권4호
• /
• pp.449-457
• /
• 2016

A stoneware bottle was recovered from the Incheon Yeongheungdo Shipwreck in 2013. Primary observations showed that this object had a sealed opening and was covered with a foreign material. After it was cleaned via mechanical and chemical methods, wave patterns were observed on the outer surface of the bottle and a yellowish-brown transparent material was found within. In this paper, the process of conserving the stoneware bottle and the analysis conducted on the unknown material found within is explained. The conservation process included steps such as cleaning, desalination and restoration. After of the missing area located at the rim, the original shape of the bottle was made clear. In addition, the unknown inner material was analyzed using FT-IR and GC-MS. Results showed that the material is similar to golden lacquer. It is speculated that the Yeongheungdo Ship had wrecked during the Unified Silla period while carrying a bottle loaded with golden lacquer.

• Journal of the Society of Naval Architects of Korea
• /
• 제43권1호
• /
• pp.1-14
• /
• 2006

To improve maritime safety, it is very important not only to make safer design and operation but also to do proper response in case of maritime casualty. The large-scaled casualties will be caused by loss of structural strength and stability due to the progressive flooding and enlargement of damage by the effect of waves and wind. To prevent foundering and structural failure, the prediction of ship motion behavior of damaged ship in wave is necessary. This paper describes the motion behavior of damaged ship in waves through theoretical and experimental studies. A time domain theoretical model of damaged ship motions and accidental flooding, which can be applied to any type of ship or arrangement and considers the effects of flooding of compartments, has been developed. The model tests have been carried out in regular and irregular waves with different wave heights and directions in ship motion basin. Those were performed for three different damaged conditions such as engine room bottom damage, side shell damage and bow visor damage of a Ro-Ro ship. Comparison of theoretical and experimental results was performed.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• 제36권3호
• /
• pp.244-248
• /
• 2000

It was investigated and analized on the construction and hull form for the ordinary fishing boat of south coast in Korea, and then analogized on the shipbuilding technology of fishing boat and fishing type around 1900 by B-spline form parameter method. The results obtained can be summarize as follows : (1) It was known that the boats used in this study have more narrow hull form than that of ancient fishing boats and their hull form was improved around 1900. (2) Keel was composed of bar keel with angle cross section. The stem corner have a material of bar stem and makes a sharp pointed stem. (3) Shell plate was jointed by the rabbetted clinker joint method. (4) It was investigated that anchovy drag net fishing boat has high L/B, L/D, B/D value as compared with drift gill net fishing boat. (5) Two boats have a good stability and particularly anchovy drag net fishing boat have a better stability value in comparison to the drift gill net fishing boat.

• Journal of the Society of Naval Architects of Korea
• /
• 제50권3호
• /
• pp.175-181
• /
• 2013

This paper presents a simulation for passenger ship evacuation considering the inclination of a ship. In order to describe a passenger's behavior in an evacuation situation, a passenger is modeled as a rigid body which translates in the horizontal plane and rotates along the vertical axis. The position and rotation angle of a passenger are calculated by solving the dynamic equations of motions at each time step. To calculate inclined angle of damaged ship, static equilibrium equations of damaged ship are derived using "added weight method". Using these equations, physical external forces due to the inclination of a ship act on the body of each passenger. The crowd behavior of the passenger is considered as the flock behavior, a form of collective behavior of a large number of interacting passengers with a common group objective. Passengers can also avoid an obstacle due to penalty forces acting on their body. With the passenger model and forces acting on its body, the test problems in International Maritime Organization, Maritime Safety Committee/Circulation 1238(IMO MSC/Circ.1238) are implemented and the effects of ship's inclination on the evacuation time are confirmed.

• Economic and Environmental Geology
• /
• 제55권2호
• /
• pp.137-148
• /
• 2022

In this study, ship movement simulation was performed based on a marine physics model for the ancient port presumed under the past environmental conditions in the coastal area of Hwaseong, which played an important role as a center of trade in the Three Kingdoms and Unified Silla periods. The paleo topographical surface was reconstructed through the analysis of borehole sediments, and the paleo coastline was extracted through the geomorphological maps published during before independence. Based on the established paleo environmental conditions of the Hwaseong coast, the marine physics model (FVCOM) was used to simulate the flow of surface currents and the route of floating materials assumed to be ancient ships. As a result, the processes of moving ships from the port to the open sea in the Eunsupo area, which is estimated location of the ancient port related to Dangseong, was well simulated, and thus the reliability of the location of the ancient port estimated by the scientific method was secured. This study is significant as a result of convergence research that encompasses archeology, history, geomorpology, geology, and oceanography.

• Journal of Navigation and Port Research
• /
• 제44권3호
• /
• pp.264-274
• /
• 2020

The Ro-Ro ferry ship capsized and sank to the bottom of the sea because of the rapid turning for several reasons, such as lack of stability due to the center of gravity rise from the extension and rebuilding of the stern cabin, excessive cargo loading, and shortage ballast, poor lashing, etc. The purpose of this study was to investigate and analyze the cause of the ship's rapid flooding, capsizing, and sinking accident according to rapid turning scientifically and accurately using the Fluid-Structure Interaction( FSI) analysis technique. Several tests were conducted for this cause investigation of the flooding and sinking accident correctly and objectively, such as the realization of the accurate ship posture tracks according to the accident time using several accident movies and photos, the validation of cargo moving track, and sea water inflow amount through the exterior openings and interior paths compared with the ship's posture according to the accident time using the floating simulation and hydrostatic characteristics program calculation, and the performance of a full-scale ship flooding·sinking simulation.

• Journal of the Korean Society of Industry Convergence
• /
• 제27권1호
• /
• pp.161-172
• /
• 2024

Approximately 89% of all capsizing accidents involve small vessels, and despite their relatively high accident rates, small vessels are not subject to ship stability regulations. Small vessels, where the provision of essential basic design documents for stability calculations is omitted, face challenges in directly calculating their stability. In this study, considering that the majority of domestic coastal small vessels are of the Chine-type design, the goal is to establish the major hull form characteristic data of vessels, which can be identified from design documents such as the general arrangement drawing, as input data. Through the application of a deep learning approach, specifically a multilayer neural network structure, we aim to infer hydrostatic curves, operational draft ranges, and more. The ultimate goal is to confirm the possibility of directly calculating the initial stability of small vessels.

• Journal of Ocean Engineering and Technology
• /
• 제33권6호
• /
• pp.518-525
• /
• 2019

Recently, the Sub-Committee on SDC (Ship Design and Construction) of IMO have discussed actively the technical issues associated with the second-generation intact stability criteria of ships. Generally, second generation intact stability criteria refer to vulnerability five modes ship stability which occurs when the ship navigating in rough seas. As waves passes the ship, dynamic roll motion phenomenon will affect ship stability that may lead to capsizing. Multi-tiered approach for second generation of intact stability criteria of IMO instruments covers apply for all ships. Each ship is checked for vulnerability to pure loss of stability, parametric roll, and broaching/surf-riding phenomena using L1(level 1) vulnerability criteria. If a possible vulnerability is detected, then the L2(level 2) criteria is used, followed by direct stability assessment, if necessary. In this study, we propose a new method to verify the criteria of the surf-riding/broaching mode of small ships. In case, L1 vulnerability criteria is not satisfied based on the relatively simple calculation using the Froude number, we presented the calculation code for the L2 criteria considering the hydrodynamics in waves to perform the more complicated calculation. Then the vulnerability criteria were reviewed based on the data for a given ship. The value of C, which is the probability of the vulnerability criteria for surf-riding/broaching, was calculated. The criteria value C is considered in new approach method using the Froude-Krylov force and the diffraction force. The result shows lower values when considering both the Froude-rylov force and the diffraction force than with only the Froude-Krylov force was considered. This difference means that when dynamic roll motion of ship, more exact wave force needs considered for second generation intact stability criteria This result will contribute to basic ship design process according to the IMO Second-Generation Intact Stability Criteria.

• Journal of the Korean Society of Marine Environment & Safety
• /
• 제25권4호
• /
• pp.413-422
• /
• 2019

Maritime accidents are always accompanied by human/property damages. If management level ship's of icers properly respond to emergency situation in a correct manner based on knowledge required by international conventions, when maritime accidents occur, it will be possible to minimize such human/property damages. To improve the ability to deal with maritime accidents, this study analyze maritime accident cases to identify which competencies ships' officers' were lacking, compared the emergency response competencies required by international conventions, analyzed various emergency management manuals of shipping companies and carried out questionnaire surveys to suggest improvements of emergency response capability for ship's master. Through the analysis of maritime accidents, it was identified that management level ship's officers lacked competencies regarding damage stability and intact stability, and that the training for emergency response required by international conventions had been insuf iciently carried out. In addition, even though emergency management manuals of ships were generally adequate, it has been identified that there were limitations in terms of practical use of emergency response manual. Therefore, based on the questionnaire, this study proposed the expansion of emergency response training required by international conventions based on use of simulators, and the development of guidelines or manuals for effective and efficient response in emergency situations.

• Journal of the Korean Society of Marine Environment & Safety
• /
• 제30권4호
• /
• pp.324-331
• /
• 2024

The height of large car and truck carriers from the keel to the wheel house is 44 ~ 46 m, and as the car-carriers increases in size, it exhibits the 'top heavy' characteristic, where the upper section is heavier than the lower section. This study aims to estimate the maximum outward heel angle of the Golden Ray car-carrier (G-ship) during turning maneuvers for accident investigation and the prevention of similar accidents. The theoretically calculated maximum outward heel is 7.5° (at 19 kn, rudder angle 35°) with a GM of +3.0 m or higher, and 16.7° with a GM of +1.85 m. Meanwhile the experimentally modified maximum outward heel is 10.5° (at 19 kn, rudder angle 35°) with a GM of +3.0 m or higher, and 23.3° with a GM of +1.85 m. The G-ship is maneuvered during an accident at a speed of 13 kn, at starboard rudder angle of 10° to 20°, it changes course from 038°(T) to 105°(T) based on the instructions of the on-board pilot. At this time, the maximum outward heel is estimated to be between 7.8° and 10.9° at the port side, which is 2.2 times higher than the normal outward heel. In the IS code, cargo ships are required to exhibit a minimum GoM of +0.15 m or more. The maneuvered G-ship exhibits a GoM of +1.72 m. It is not maneuvered because it fails to satisfy the international GoM criteria and because its GoM is insufficient to counteract the heeling moment during the maneuver. This study is performed based on accident-investigation results from the Korea Maritime Safety Tribunal and the USCG.