• Proceedings of the Computational Structural Engineering Institute Conference
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• 2005.04a
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• pp.696-703
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• 2005

Recently, the collision problems between a bridge and a navigating ship are frequently issued at the stage of structure design. Even the many study results about vessel to vessel collision are presented, but the collision studies between vessel and bridge structure have been hardly presented. In this study, nonlinear dynamic analysis of vessel and fender system carry out using ABAQUS/Explicit commercial program with consideration of some parameters, such as bow structure we composed to shell element also ship's hull is modeling to beam element. Also, buoyancy effect is considered as spring element. The two types of fender systems was comparable with both collision analysis about steel materials fender system and rubber fender system On the purpose of study is analyzed the plasticity dissipated energy of vessel and fender system. We blow characteristic that kinetic energy is disappeared by plastic large deformation in case of collision. Also, We considered dissipated kinetic energy considering friction effect.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2005.04a
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• pp.143-150
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• 2005

In this study, to evaluate the collision behaviors of the navigating vessel and the dolphin protective system protecting the substructures of bridges, the numerical simulation was performed. The analysis model of vessel bow that the plastic deformations are concentrated was composed by shell elements, and the main body of vessel was modeled by beam elements to represent the mass distribution and the change of potential energy. The material model reflecting the confining condition was used for the modeling of the filling soil of dolphin system. The surrounding soil of the dolphin system was modeled as nonlinear springs. As results, it is verified that the dolphin system can adequately dissipate the kinematic energy of the collision vessel. The surrounding soil of the dolphin system is able to resist the collision force of the vessel. And the major energy dissipation mechanism of collision energy is the plastic deformation of the vessel bow and the dolphin system.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2008.04a
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• pp.380-385
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• 2008

3 DOFs model for the collision analysis of a bridge super-structure and a super-structure of the navigating vessels were proposed and analyzed. The collision event between the super-structure of vessel and the super-structure of bridge are different from the normal collision event that collided at sub-structure of bridge. Because of its moment arm, the stability force of vessel could affect to the collision behaviors. To consider this effect, 3 DOFs model including two translation DOFs and one rotational DOF were introduced. The restoration forces of the collision system were considered as nonlinear springs. The equations of motion were derived if form of differential equations and numerically solved by 4th order Runge-Kutta method. The accuracy and the feasibility of this model were verified by the numerical example with parameter of moment arm length.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2001.05a
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• pp.197-200
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• 2001

A manufacturing process of composite pressure vessel was studied. The vessel was fabricated using the filament winding process. It is utilized as a container of high pressure Helium gas which propels a rocket fuel and an oxidizer. The layup patterns were determined based on the lamination theory. 3-axis controlled filament winding machine was developed to realize the patterns. The vessel was successfully fabricated using the developed machine. And the hydraulic pressure test was performed to measure an applied pressure-strain relations on the composite vessel.

• Journal of the Korean Society of Industry Convergence
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• v.9 no.4
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• pp.247-253
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• 2006

Power consumption for double-stage paddle impeller in spherical and cylindrical agitated vessel was measured over a wide range of Reynolds number from laminar to turbulent flow regions. The power correlation was obtained which was applied to both spherical and cylindrical vessel, when the apparent diameter of the spherical vessel was equal to the diameter of the cylindrical vessel which had a height equal to its diameter and had the same volume as the spherical vessel. The power consumption for the double-stage impeller was dependent upon the distance of among the impeller in the agitated vessels, as follows: $$f/2={\frac{C_L}{Re_G}}+{\frac{Ct}{2}}({\frac{C_tr}{Re_g}}+Re_g)^{-m}$$

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.05a
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• pp.743-749
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• 2005

In this work, two dynamic absorbers are introduced and designed to reduce the vibration of the large-size pressure vessel of a reactor for a petrochemical plant. The vibration modes and harmonic responses of the vessel are firstly analyzed by the finite element method. On the basis of the analyzed results, two dynamic absorbers are designed by a simple design theory. Furthermore, an optimization process is executed and an optimal design of the dynamic absorber is obtained to improve performance and structural safety of the vessel. As a result, the maximum displacement and stress of the vessel is decreased about 85% and 65% respectively, the design criteria being satisfied.

• Journal of the Korean Institute of Navigation
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• v.19 no.3
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• pp.67-81
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• 1995

There is a vessel which shall not impede the passage of any other vessel in the COLREGS 1972. But the issue was raised that the words of "not to impede" were vague. Therefore, IMO adopted new paragraph (f) to be added to Rule 8 that a vessel which is required not to impede the passage of another vessel is not relieved of this obligation if approaching the vessel so as to involve risk of collision. It means that the ship which is obliged not to impede should contributes to avoid collision and to the safe passage of the other vessel. Also it results that the application of Collision Rules should be changed. But until now, it seems that the mariners are not familiar with this subject. This paper, therefore, aims to define the meaning of "not to impede" and clarify it's legal concept so as to adequate application of the Collision Rules for the collision avoidance at sea.on avoidance at sea.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.44 no.1
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• pp.75-80
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• 2008

A scrapped fiber-reinforced plastic(FRP) fishing vessel causes many environmental problems, because technology development for recycling FRP vessel has not been adequately addressed. FRP is a main material for constructing a small coastal fishing vessel that is an object of reduction policy. Therefore, the FRP wastes derived a scrapped fishing vessel are increasing. In this study, I investigated an effective disposal process for FRP through the analysis of the actual conditions of scrapped FRP fishing vessel. The treatment processes of scrapped FRP fishing vessel are carried out with oil-removing, dismantling, intermediated processing(crushing), and then reclaiming follows burning in the final processing in Korea. However, in Japan, several recycling methods have been developed, for example, the incineration including thermal recovery, the use of cement-reclamation, and the use of asphalt concrete aggregate, because the method of reclaiming after incinerating which is generally used in Korea produces a toxic by-product such as dioxin.

• Proceedings of KOSOMES biannual meeting
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• 2006.11a
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• pp.143-149
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• 2006

This paper is primarily focused on the safe navigation between overtaking and overtaken vesselsin restricted waterways under the external forces, such as wind and current. The maneuvering simulation between two ships was conducted to find an appropriate safe speed and distance, which is required to avoid collision. From the viewpoint of marine safety, a greater transversedistance between two ships is more needed for the smaller vessel. Regardless of external forces, the smaller vessel will get a greater effect of hydrodynamic forces than the higher one. In the case of close navigation between ships under the forces of wind and current, the vessel moving at a lower speed is potentially hazardous because the rudder force of the lower speed vessel is not sufficient for steady-state course-keeping, compared to that of the higher speed vessel.

• Proceedings of the KIEE Conference
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• 2005.10b
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• pp.3-5
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• 2005

Vessel boundary detection and modeling is a difficult but a necessary task in analyzing the mechanics of inflammation and the structure of the microvasculature. In this paper we present a method of analyzing the structure by means of an active contour model(using GVF Snake) for vessel boundary detection and 3D reconstruction. For this purpose we used a virtual vessel model and produced a phantom model. From these phantom images we obtained the contours of the vessel by GVF Snake and then reconstructed a 3D structure by using the coordinates of snakes.