• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.3
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• pp.319-324
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• 2018

The collision problem is one of the design factors that must be carefully considered for the risk of collision occurring during the operation of ships and offshore structures. This paper presents the main results of the ship collision study, and its main goal is to analyze potential crash scenarios that may occur in the FLNG (Floating Liquefied Natural Gas) considering the likelihood and outcome. Consideration being given to vessels visiting the FLNG and surrounding vessels navigating around, such as functionally supported vessels and offloading carriers. The scope includes vessels visiting the FLNG facility such as in-field support vessels and off-loading carriers, as well as third party passing vessels. In this study, based on QRA (quantitative risk assessment), basic research methods and information on collision are provided. Based on the assumptions and methodologies documented in this study, it has been possible to clarify the frequency of collision and the damage category according to the type of visiting ship. Based on these results, the risk assessment results related to the collision have been derived.

• Journal of Navigation and Port Research
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• v.38 no.6
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• pp.689-694
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• 2014

The Korean government has introduced and enforced maritime traffic safety assessment to secure traffic safety since 2010. The maritime traffic safety assessment is needed by law to design a new port or modify an existing one. According to Korea Maritime Safety Act, in the assessment the propriety of marine traffic system consists of the safety of channel transit and berthing/unberthing maneuver, safety of mooring, and safety of marine traffic flow. The safety of channel transit and berthing/unberthing maneuver can be evaluated only by ship-handling simulation. The ship-handling simulation is carried out by sea pilots working with the port concerned. The vessel's proximity measure is an important factor to evaluate traffic safety. The proximity measure is composed of vessel's closest distance to channel boundary and probability of grounding/collision. What is more, the probability of grounding becomes important. According to central limit theorem, a sample has a normal distribution on condition that its size is more than 30. However, more than 30 simulation runs bring about the increase of assessment period and difficulty of employing sea pilots. Therefore this paper is to find out minimum sample size for evaluating vessel's proximity. First sample sets of size of 3, 5, 7, 9 etc. are selected randomly on the basis of normal distribution. And then KS test for goodness of fit and t-test for confidence interval are applied to each sample set. Finally this paper decides the minimum sample size. As a result this paper suggests the minimum sample size of 5, that is, the simulation of more than five times.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2009.06a
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• pp.30-31
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• 2009

Through the full scale ship collision response analysis of high speed passenger ship with underwater floating matters, the objective of this study is to perform the crashworthy safety assessment of its hull and passengers. For this safety assessment, diverse collision scenarios could be established through the thorough understanding of damage mechanisms due to the collision of its hydrofoil system with underwater floating matter examining the damage informations of its hull and passengers from the collision accidents, and through the estimation of the damages of its hull and passenger. The next step, crashworthy safety assessment of its hull and passengers, was carried out by the collision response analyses of high speed passenger ship with underwater floating matter using Fluid-Structure Interaction(FSI) analysis technique of LS-DYNA code in consideration of surrounding water, and using local zooming analysis technique.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2011.10a
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• pp.114-116
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• 2011

By 33 CFR 154.828 regulation, a liquid seal must be installed on the inlet to vapor destruction unit in vapor control system. However, install and maintenance of liquid seal are subject to many problems in ship environment. Therefore, US Coastguard, which is the governing body of the regulation, have prepared another clause in the regulation for the exemption from previous clauses. In this paper, relevent regulation is reviewed, together with the requirements for exemption from liquid seal installation. A previous example case is also studied to propose how safety assessment for the alternative safety devices replacing liquid seal should be performed.

• Journal of the Society of Naval Architects of Korea
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• v.40 no.6
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• pp.30-36
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• 2003

To improve survivability of damaged ship, assessment of stability and structural safety, and behavior analysis in wave is required. Prediction of sinking time, damage stability and structural strength considering progressive flooding and dynamic force in wave is very important. To do it, a geometric model which can be express damaged ship is prepared. This paper described the geometric modeler for survivability assessment of damaged ship. The modeler is developed based on 3-D geometric modeling kernel, ACIS. The hull form and compartment definition is available fundamentally. And requirement for modeler contains data generation and interface for hydrostatic calculation, behavior analysis, and longitudinal strength analysis and so on. To easy access modeling system by conventional user such as crew, user interface is developing.

• Journal of the Korean Society of Marine Environment & Safety
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• v.21 no.3
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• pp.297-302
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• 2015

To prevent cargo accidents by repeated loads, a continuous monitoring for securing rope or additional safety measures are needed, but most of prevention measures have been conducted only by operator's own experience not a quantitative assessment. Hence, the Load-Displacement curve and approximation formula of securing rope were drawn in this research for a quantitative assessment and simplified measurement on a tension of securing rope using a tensiometer. Moreover, a com parison was conducted between m easuring tension and calculated tension on securing rope with portable tensiometer, 'Load-Displacement' approximation formula. The calculated tension of securing rope is obtained 153.3kfg using the formula and that result has not much difference with initial tension 150.0kgf. Lastly, an analysis of the characteristics of various ropes was suggested to enhance the reliability about quantitative assessment of securing rope's tension through further research.

• Journal of the Society of Naval Architects of Korea
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• v.40 no.2
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• pp.34-40
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• 2003

Ship damage due to maritime casualties lead to marine pollution, loss of life and properties. The maritime casualties come from the rough sea and bad weather condition generally. Therefore the large-scaled casualties will be derived from loss of structural strength and stability due to the progressive flooding and enlargement of damage by the effect of wave and wind. The improvement of damage survivability is very important in maritime safety This paper described the damage survivability assessment system which can be evaluate and improve the ship safety in consideration of loading, sea and damage condition. The components of the system and decision criteria for damage stability and structural safety is established. The ship modeler and behavior analysis program in wave is developed. Finally further research work is also discussed.

• Journal of the Korean Society of Marine Environment & Safety
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• v.7 no.3
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• pp.61-74
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• 2001

The prevention of marine accidents has been a major topic in marine society and various policies and countermeasures has been developed, applied to the industries. Formal Safety Assessment is a structured and systematic methodology, aimed at enhancing maritime safety, including protection of life, health, the marine environment and property, by using risk and cost-benefit assessments. In addition, it provides a means of being proactive, enabling potential hazards to be considered before a serious accident occurs. In this paper, we has been screening and ranking of hazards using fuzzy structural modeling method and quantitative risk assessment for the ship's collision in the last 10 years marine accidents.

• Journal of the Korean Society of Marine Environment & Safety
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• v.4 no.2
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• pp.25-33
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• 1998

This paper deals with PC-based ship handling simulator, which is now widely utilized not only for total assessment of safety in harbour area but also for training purpose. The suitable mathematical model for low advance speed manoeuvre is treated with the effects of current, wind, wave, tug force and water depth. We adopt 3 dimensional graphic technique for perspective representation of relative ship motion. Some graphical panels on the screen are devised for data input/output or ship manoeuvring information. We show the real time simulation of berthing menoeuvre applied to Pusan harbour as an example.

• Journal of Ship and Ocean Technology
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• v.4 no.4
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• pp.1-18
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• 2000

The paper describes a formalisation of a Design for Safety methodology in an integrated envi-ronment, outlines early developments of a software tool, and presents the results of an appli-cation of the methodology to a case study. The approach adopted attempts link safety per-formance prediction through the utilisation of appropriate technical tools, safety assessment deriving from risk-based methodologies and disparate design activities and issues. Black-board systems have been utilised as the platform in the development of the integrated design environment, allowing safety assessment to become an integral part of the design process. Finally, the case study addresses the application of the developed methodology to three dif-ferent arrangements of a conventional passenger Ro-Ro vessel, with the aim to demonstrate the validity of the process and methodology adopted. The findings are presented and dis-cussed, and recommendations given for the way forward.