• Korean Journal of Remote Sensing
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• v.15 no.2
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• pp.175-181
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• 1999

A recurring eddy which located at the terminal end of the Korean East Warm Current was captured on ocean color and sea surface temperature imagery from satellite in spring and autumn. During late April, 1997 thermal infrared imagery from the NOAA AVHRR sensor and ocean color data from the Japanese ADEOS-I OCTS sensor, revealed this feature. The cold core had elevated chlorophyll concentrations, based on OCTS estimates, of greater than 3 mg/m$^3$ while the warmer surrounding waters had chlorophyll concentrations of 1 mg/m$^3$ or less. The elevated cholophyll accociated with this eddy has not been previously described. The eddy is also evident in SST images from autumn, but the SST in the core is warmer than in spring, and the warm jet flowing to the west of the eddy is also warmer is autumn compared to spring. A reccurring eddy and the high chlorophyll_a concentration area which surround around the eddy show on NOAA and SeaWiFS images in March 2, 1998. The eddy forms at the northern extent of the Korean East Warm Current as those waters collide with the cold, south-flowing Liman Current over a topographic shelf about 1500 m deep. This region of the eddy formation appears to have a strong connection with the dynamics of the western part of the polar front eddy field that dominates surface mesoscale structure in the central East (Japan) Sea. Interaction of the eddy with ARGOW tracked drifters, and evidence for its persistence are discussed.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.27 no.9
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• pp.1262-1272
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• 2003

A two-dimensional direct numerical simulation is performed to investigate the dynamic behaviors of a single vortex in counter reacting and non-reacting flow field. A predictor-corrector-type numerical scheme with a low Mach number approximation is used in this simulation. A 16-step augmented reduced mechanism is adopted to treat the chemical reaction. The budget of the vorticity transport equation is examined to reveal a mechanism leading to the formation, destruction and transport of a single vortex according to the direction of vortex generation in reacting and non-reacting flows. The results show that air-side vortex has more larger strength than that of fuel-side vortex in both non-reacting and reacting flows. In reacting flow, the vortex is more dissipated than that in non-reacting flow as the vortex approach the flame. The total circulation in reacting flow, however, is larger than that in non-reacting flow because the convection transport of vorticity becomes much large by the increased velocity near the flame region. It is also found that the stretching and the convection terms mainly generate vorticity in non-reacting and reacting flows. The baroclinic torque term generates vorticity, while the viscous and the volumetric expansion terms attenuate vorticity in reacting flow. Furthermore, the contribution of volumetric expansion term on total circulation for air-side vortex is much larger than that of fuel-side vortex. It is also estimated that the difference of total circulation near stagnation plane according to the direction of vortex generation mainly attributes to the convection term.

• Journal of the Korea Computer Graphics Society
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• v.18 no.3
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• pp.17-27
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• 2012

In this paper, we describe a case study of the film 'Sector 7' which was produced by technologies applied fluid simulation. For the CG scenes in the movie which include highly detailed fluid motions, we used smoothed particle hydrodynamics(SPH) technique to express subtle movements of seawater from a crashed huge tank, and used hybrid simulation method of particles and levelsets to describe bursting water from a submarine's broken canopy. We also used detonation shock dynamics(DSD) technique for detailed flame simulations to produce a burning monster, the film"s main character. At this point, the divergence-free vortex particle method was applied to conserve the incompressible property of fluids. In addition, we used an upsampling method to achieve more efficient video production. Consequently, we could produce the high-quality visual effects by using the domestic technologies.