• International Journal of Ocean Engineering and Technology Speciallssue:Selected Papers
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• v.6 no.1
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• pp.15-21
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• 2003

A common feature in the three-dimensional numerical model experiments of coastal discharge with simplified model and idealized external forcings is investigated. The velocity fields due to the buoyancy and flaw flux, are spreaded radiately and the surface velocites are much greater than the homegeneous discharges. The coastal dischargd due to the Coriolis force and flaw flux are shaped a anticyclical gyre (clockwise) and determined the scale of the gyre in the coastal zone, respectively. The bottom topography restricts a outward extention of the coastal fronts and it accelerates a southward flow.

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 2002.08a
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• pp.191-197
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• 2002

The prediction of the dynamic behaviors of buoyant water discharges into a large volume of water bodies, the flows of water accompanying the density differences due to temperature differences and sometimes also to salinity differences, have attracted great concern over several decades. Heated water surface discharges from power plants and freshwater discharges in estuaries are typical examples of the buoyant flows. (omitted)

• Journal of Ocean Engineering and Technology
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• v.17 no.2
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• pp.1-7
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• 2003

A common feature in the three-dimensional numerical model experiments of coastal discharge with simplifed model and idealized external forcings is investigated. The velocity fields due to the buoyancy and flow flux, are spreaded radiately and the surface velocites are much greater than homegeneous discharges. The coastal dischargd due to the Coriolis force and flow flux are shaped a anticyclical gyre (clockwise) and determined the scale of the gyre in the coastal zone, respectively. The bottom topography restricts a outward extention of the coastal fronts and it accelerates a southward flow.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.16 no.4
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• pp.213-223
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• 2004

The discharges of groundwater flow were estimated using Darcy's method along the coastal zone in the Masan Bay. The estimates using the information, i.e., groundwater level, location of the observation well, hydraulic conductivity, the thickness of the aquifer, and coastline length, were 1.65% of the precipitation of the watershed. The estimated groundwater discharges through fractured rock aquifer and the aquifer with sedimentary material were $0.7\times10^4$$m^2/year$and $1.0\times10^7$$m^3/year$ respectively. Whereas, the discharge estimated by KORDI (2003) using isotopes method is about 20 times larger than the estimates from this study because of the influence of the re-circulated seawater through the coastal zone aquifer. In order to quantify this effect in detail, the groundwater levels and salinity changes in the observation wells located in the coastal zone should be continuously monitored and analyzed.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2012.11a
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• pp.7-11
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• 2012

Plasma electrolytic oxidation of magnesium alloys is a well known technique to produce corrosion and wear resistant coatings. The addition of particles to the electrolyte provides a possibility to produce coatings with an increasing range of composition by in-situ incorporation of those particles into the coating. An extensive literature review has revealed that the mode of incorporation depends mainly on the melting point of the used particles and the energy provided by the discharges of the PEO process. The spectrum ranges from inert to partly reactive incorporation, but a complete reactive incorporation and a formation of a new single phase coating was not observed so far. Thus a new approach in PEO processing is introduced using specific particles as a kind of sintering additive, changing not only the composition but lowering the melting temperature and increase the liquid phase fraction during the discharges, resulting in a new amorphous coating.

• Ocean and Polar Research
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• v.22 no.1
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• pp.45-56
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• 2000

Hydrodynamic mixing characteristics of submerged effluent discharges into Masan Bay were investigated by both field observations and numerical model simulations. CORMIX model, a length-scale mixing model, was adopted to obtain the near-field dilution and wastefield characteristics of the effluent discharges into Masan Bay. Model predictions of the near-field dilution rates were in a good agreement with field observations in summer and winter seasons. Seasonal variations in the dilution rates showed that the highest dilution rate was obtained in winter while the lowest dilution rate was in summer. As the effluent discharges are increased with the treatment capacity expansion to be completed by 2011, the dilution rates are expected to be much reduced and the near-field stability of the wastefields will become unstable due to the increased effluent discharges.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2014.10a
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• pp.87-88
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• 2014

The Coastal sediment is highly contaminated due to ship transportation, industries discharges and urban sources. Various contaminants release into seawater and settle in marine sediment and it significantly affect marine eco system. In the present study evaluated the optimization of slow release biostimulant ball (BSB) in coastal sediment in busan. The effective variables like BSB size, distance and month variables on VS reduction was determined by using Response surface methodology(RSM). The analysis of variance (ANOVA) and coefficient determination (R2) of VS was 0.9369 and maximum reduction of VS was obtained in 3cm ball size and 5.5cm distance and 4 month interval time. This result revealed that the BSB in effective VS reduction in coastal sediment.

• Proceedings of the KSRS Conference
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• v.1
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• pp.126-129
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• 2006

The marine environment is under considerable threat from intentional or accidental oil spills, ballast water discharged, dredging and infilling for coastal development, and uncontrolled sewage and industrial wastewater discharges. Monitoring spills and illegal oil discharges is an important component in ensuring compliance with marine protection legislation and general protection of the coastal environments. For the monitoring task an image processing system is needed that can efficiently perform the detection and the tracking of oil spills and in this direction a significant amount of research work has taken place mainly with the use of radar (SAR) remote sensing data. In this paper the level set image segmentation technique was tested for the detection of oil spills. Level set allow the evolving curve to change topology (break and merge) and therefore boundaries of particularly intricate shapes can be extracted. Experimental results demonstrated that the level set segmentation can be used for the efficient detection and monitoring of oil spills, since the method coped with abrupt shape’s deformations and splits.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.23 no.1
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• pp.101-108
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• 2011

The purpose of salinity intrusion due to numerical simulation is analaysis for saline intrusion to the upstream channel in Nakdong River Estuary Barrage(NREB) to get enough fresh water. Conditions that occur salinity intrusion affect by tidal distribution at seas, so salinity concentration changes according to tidal phenomenon. Making this connection cleary can help preventing salinity intrusion. In this study, estimating salinity intrusion to the upstream channel in NREB using EOMSED model, we reexamine NREB's existence. Comparison is also made with observing data. In result, when inflow discharges at $75m^3/s$ is more similar with respect to observing data than $130m^3/s$ at ECOMSED model. Thus, estimations are more precise at little discharges than lots of discharges.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.9 no.2
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• pp.74-85
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• 1997

Accurate analysis of water budget and seawater exchange characteristics is essential for the improvement and management of the degraded water quality in Masan Bay. In this study, water budget is simulated for the four divided coastal zones on the monthly base, and watershed runoff discharges which are important as input parameters are estimated using the runoff coefficient(=0.7). The main results are as follows : The runoff-contribution rate due to water supply discharge is increased from 10% in 1978 to the equivalent amount at present. The reduction quantity due to the wastewater interception is about 25% of total inflow discharges, and the net effects of both precipitation and evaporation is about 10%. As the hydraulic detention time in Masan Bay is estimated about 3 months, water exchange rate is to be very low. From the analysis of the salinity variation on account of water mixing, it appears no temporal correlation between monthly average precipitation and salinity, whereas only regional correlation is apparent.