• International Journal of Ocean Engineering and Technology Speciallssue:Selected Papers
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• 제6권1호
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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.

• 한국해안해양공학회:학술대회논문집
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• 한국해안해양공학회 2002년도 한국해안해양공학발표논문집 Proceedings of Coastal and Ocean Engineering in Korea
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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)

• 한국해양공학회지
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• 제17권2호
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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.

• 한국해안해양공학회지
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• 제16권4
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• pp.213-223
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• 2004

마산만 연안유역의 지하수 유출량을 Darcy 방법을 이용하여 추정하였다. 지하수위, 관정의 위치, 투수계수, 대수층 두께, 해안선 길이 정보를 이용하여 추정한 지하수 유출량은 강우량 대비 1.65%정도이다. 마산만 유역의 암반층을 통한 지하수 유출량은 $0.7\times10^4$ $m^2/year$정도로 추정되었으며, 충적층을 통한 지하수 유출량은 $1.0\times10^7$$m^3/year$정도로 추정되어 암반층을 통한 유출량은 무시할 만한 정도로 파악되었다. 한편, 한국해양연구원(2003)에서 방사성 동위원소를 이용하여 추정한 지하수 유출량은 본 연구에서 추정한 지하수 유출량의 20배 정도에 해당하지만, 이는 연안 대수층으로 침입한 재순환 해수의 영향으로 파악되었으며, 해안선에 근접한 관측정의 운영을 통하여 지하수위 및 염도 변화를 지속적으로 관측하여 재순환해수의 정량적인 영향분석을 보다 상세하게 연구할 필요가 있는 것으로 판단된다.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2012년도 추계총회 및 학술대회 논문집
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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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• 제22권1호
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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.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2014년도 추계학술대회
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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.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume I
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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.

• 한국해안·해양공학회논문집
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• 제23권1호
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• pp.101-108
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• 2011

염분도 수치계산의 목적은 낙동강 하구둑 상류로 침투되는 염수 쐐기 침입을 분석하여 담수량을 확보하는데 있다. 염분 침투가 발생되는 조건은 바다에서의 조석 분포에 따라서 침투길이가 달라지고 있으므로 염분농도는 조석의 현상에 따라서 달라진다. 이러한 현상을 확실히 파악하면 보다 효율적으로 염분 침투를 차단할 수 있다. 본 연구에서는 염분 침투에 대해서 ECOMSED 모델을 이용하여 낙동강 하구둑 상류로 침투되는 염분농도를 정확히 추정함으로써 낙동강 하구둑의 존재를 재평가하게 될 것이다. 또한 이 모델의 타당성을 입증하기 위해 실제 관측값과 비교하였다. 분석결과 ECOMSED모델은 상류 유입유량이 $130m^3/s$의 경우가 $75m^3/s$보다 실제 관측값과 거의 동일한 값을 나타내었다. 따라서 유입유량이 많은 경우가 적은 경우보다 예측이 정확한 것을 알 수 있다.

• 한국해안해양공학회지
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• 제9권2호
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• pp.74-85
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• 1997

마산만의 악화된 수질을 개선하고 관리하기 위해서는 정확한 물수지 및 해수교환 특성 분석이 선결되어야한다. 본 연구에서는 모형적용 영역을 4개의 해역으로 분할하여 월별로 물수지를 분석하였으며, 중요한 입력자료인 유역 유출량은 유출계수(=0.7)를 이용하여 추정하였다. 물수지 분석모형을 마산만 및 인근해역에 적용한 결과는 다음과 같다. 마산만 유역의 용수공급에 의한 유출기여율은 1978년 10% 수준에서 점차 증가하여, 현재는 강우에 의한 유출량과 대등한 수준이다. 또한, 하수 차집관거에 의한 유출저감량은 총 유입량의 약 25% 정도이며, 강우 및 증발에 의한 순영향은 10% 정도이다 한편, 마산만의 수리하적 정체시간은 약 3개월(97일)로, 해수교환이 잘 이루어지지 않는다. 해수교환에 의한 염도변화를 분석한 결과 월평균 강우와 염도의 시기적인 상관성은 없고, 염도간 지역적인 상관성만이 있는 것으로 나타났다