• Journal of Navigation and Port Research
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• v.27 no.2
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• pp.193-198
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• 2003

The slew motion of a single point moored ship by the external forces is considered to control itself. The maneuvering equations of motion are derived to express the motion of a ship. The wind forces and the wave forces are considered as the external forces of the single point moored ship in the simulation. The wave forces in the time domain analysis are generated from the frequency transfer function calculated by 3-D source distribution method. The wind forces are used the results from OCIMF(1994). To control the slew motion, the bow thruster and the bridle anchoring with 2nd anchor are used in the numerical simulation.

• Journal of Navigation and Port Research
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• v.27 no.1
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• pp.55-61
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• 2003

The maneuvering equations of motion are derived to express the motion of a ship. The wave forces in the time domain analysis are generated from the frequency transfer function calculated by 3-D source distribution method. The linear wave forces whose periods are equal to those of incident waves and the nonlinear wave forces that make long period drift forces are computed for the simulation. The consideration of irregular waves and nonlinear wave force effects on the slew motion are carried on the analyzing the motion of ship in the regular and irregular waves.

• Transactions of the Korean hydrogen and new energy society
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• v.28 no.2
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• pp.212-219
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• 2017

As an environmental pollution and global warming due to an excessive carbon emission are intensified, the importance of renewable energy is in rise today. TCP (Tidal Current Power), one of the renewable energy sources, generates electricity by converting kinetic energy of current into rotational energy of turbine. Also the TCP has a great advantages of predictability and reliability. Because the generating power is proportional to cubic of stream velocity, amplifying current speed by applying duct is highly effective to increase the generating power. SPM (Single Point Mooring) can be applied for the weather vane with various current direction and also augments generating power of the system. In addition, simple installation and retrieval could be a merit of SPM system. By combining duct and SPM, TCP system for relatively low-speed-current and shallow water region can be feasible and economical. In this study, single point moored duct-type TCP system was designed and the motion of submerged structure was investigated in both numerical and experimental method. DNV wadam V4.8-1 and OrcaFlex 10.0a were used for the frequency and time domain motion analysis of system respectively. Duct model scaled by 0.05 of Froude conformity ratio and CWC (Circulate Water Channel) are used for experiment.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2000.10a
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• pp.84-89
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• 2000

Thermal simulation of typical stack-type and newly proposed planar-type micro-gas sensors were studied by FEM method. The thermal analyses for the proposed planar structure including temperatur distribution over the sensing layer and power consumption of the heater were carried using finite element method by computer simulation and well compared with those of typical stack-type micro-gas sensor. The thermal properties of the microsensor from thermal simulation were compared with those of a actual device to investigate the acceptability of the computer simulation.

• Journal of the Society of Naval Architects of Korea
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• v.46 no.6
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• pp.659-666
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• 2009

Recently, there are several problems in space, contiguity and facility of the existing harbors issued due to the trend of enlarging the container capacity of the large container vessel, the Mobile Harbor has been proposed conceptually as an effective solution for those problems. This concept is a kind of transfer loader of the containers from the large container ship, which is a floating barge with a catamaran type in the underwater part, and so prompt maneuverability and work effectiveness. For the safe mooring of two floating bodies, a container and the mobile harbor, in the near sea apart from the quay, a robot arm mooring facility specially devised would be designed and verified through comparison study under various environmental sea condition in the inner and outer harbor. DP system (Dynamic Positioning System) using the azimuth thruster and a pneumatic fender, etc, will be considered as a next research topic for the mooring security of multi-body floaters.

• Journal of Navigation and Port Research
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• v.42 no.3
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• pp.167-176
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• 2018

A solar power generation system on single point moored offshore plant has independent power system In order to satisfy the maritime environment and account for the number of sunless days, it is important to supply stable electric power to the systems. For these reasons, solar panels are installed in multiple directions. However, a partial shading effect occurs because the amount of light incident on each panel is different. The generated power by the solar generation system installed on land is affected by the latitude, then it is installed at an angle of 30 to $45^{\circ}$. in the case of Korea. In the case of a solar power generation system installed in a mooring type of marine plant, there is a possibility that the maximum power point is outside of the controllable range due to the partial shading effect. Therefore, a power generation loss occurs. By reducing the light amount difference between both panels, the maximum power point can exist in a range where the MPPT algorithm can track the power. The purpose is so the power generation efficiency can be further increased. In this paper, simulation results show that the highest power generation efficiency is obtained at an installation angle of $20^{\circ}$.

• Journal of the Society of Naval Architects of Korea
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• v.50 no.1
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• pp.8-13
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• 2013

Excessive yaw motion of a turret moored vessel was examined in this paper. The vessel was moored by an internal turret and catenary mooring lines. The experiments were conducted in regular waves. Turret moored vessel can oscillate from side to side or move to one particular direction, and eventually exhibit large yaw motion. The results showed that the excessive yaw occured for specific condition, ratio of wave lengths and vessel length. It was found that turret moored floating vessel was unstable for regular wave period from 14 to 18 sec and excessive yaw occurred to maximum 50 deg. The time series, trajectory, phase plot and qualitative analysis are performed. The analysis showed that the results of experiments agreed with the that of analytic method and the excessive yaw could be predicted by the stability analysis.