• 한국해안·해양공학회논문집
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• 제24권5호
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• pp.319-325
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• 2012

조간대 저서생물들의 서식환경을 결정하는 중요한 인자 중의 하나인 노출시간을 추정하는 공식을 개발하였다. 이 공식은 기존의 1시간 간격, 1년 기간 조위자료를 이용하여 노출시간을 추정하는 방법과는 달리 대부분 연안의 기본 조석 정보에 해당하는 주요 4분조 조화상수들을 이용하여 노출시간을 간단하게 계산할 수 있다. 서해안의 관측 조위자료를 이용한 노출시간과 본 연구에서 개발한 공식에 의한 추정결과를 비교한 결과 RMS 오차는 0.8-1.4%로 파악되었다. 본 공식은 장기간의 조위자료가 없는 조간대 지역에서 간단하면서도 정확한 노출 시간 및 침수시간 추정에 활용할 수 있다.

• 자원환경지질
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• 제33권5호
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• pp.417-424
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• 2000

We applied SP monitoring and resistivity surveys using the pole-pole electrode array to seawater leakage problems in the Youngsan estuary dam and the Eoeun embankment to estimate and detect the zone of seawater leakage. The embankment is generally affected by tidal variation and has low resistivity characteristics due to the high saturation of seawater. For this reason, SP monitoring and the pole-pole array resistivity surveys, which are relatively more effective to the conductive media, were carried out to delineate the leakage zones of sea water through the embankment. We checked out electrical conductivity (EC) and temperature variations along the inner part of Youngsan estuary dam to detect the zone of seawater leakage and found that the measured EC value agreed to that of seawater in the leakage zone and the temperature was lower than that of the vicinity of leakage zone. SP monitoring results were coincided with tidal variations at each embankment. At the leakage zones in the Youngsan estuary dam and the Eoeun embankment, SP anomalies are in the range of -60~-85 mV and -20~-50 mV, respectively, and true resistivity values obtained by 2-D inversion are 3~15 ohm-m and below 0.3 ohm-m, respectively. Both SP monitoring and the pole-pole array resistivity method are found to be quite effective for investigation of seawater leakage zones in the embankment.

• 한국해양공학회지
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• 제20권4호
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• pp.58-63
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• 2006

When the costal zone surrounded by a breakwater has a narrow vertical opening, currents in the vicinity of a narrow entrance can result in a jet flow, coinciding with the tide. Such a Tidal-Jet Generator(TJG) can change the water mass distribution and transport processes in the domain of influence of the jet. Also, it can decrease the residual time of them. In the present study, the water purification utilizing tidal jets in the coastal zone over constant bathymetry are estimated numerically, using a finite-difference numerical scheme, named the NS-MAC-TIDE method, which isbased on the fully 3D Navier-stokes(NS) equations. The shear velocity near the inlet of the TJG are predicted from the flow field simulation, and are assessed qualitatively with the development of scouring or sediment that is caused by the change of diffusion or sweeping flowup from the seabed of sediment particles. Finally, through solving a transport equation of concentration, the residual time related on mass transport processes and the flushing mechanism for water purification are investigated.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2002년도 학술발표회 발표논문집
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• pp.133-136
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• 2002

A simulation by the TOPAS model, two dimensional finite difference model was performed on the flows through drainage lock gate for the Saemangeum tidal reclamation project. Analysis focus on the changes of intertidal zone areas according to the operation scheme of the gate. The intertidal zone areas were analyzed as $66{\sim}70\;km^2$ when the opening of the gate was 300 m. It occupied about $85{\sim}90%$ of intertidal zone areas compared to that the Mangyung sea basin was opened without sea-dike. It appeared to be the most effective in terms of securing enough intertidal zone areas when the gate was operated as inflowing sea-water after 2 day's drainage.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2013년도 추계 학술논문 발표대회
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• pp.60-61
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• 2013

For reinforced concrete structures located in a sea environment, the Impressed Current Cathodic Protection (ICCP) is mostly used as a signature method to prevent steel corrosion. For this research, specimens to which the ICCP is applied were manufactured under the assumption of two following cases the specimens are exposed to various salt damage environments (submerged zone, tidal zone), and deteriorative factors (crack) occur in concrete. For the specimens manufactured, an enhancement experiment for deterioration was conducted through regular cycle change under the temperature between 15 ~ 70℃ with 70 ~ 90% humidity. Afterwards, the method effect was verified through a half-cell method and application of the ICCP derived from salt damage environments was investigated.

• 대한원격탐사학회지
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• 제25권6호
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• pp.501-505
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• 2009

Quasi-linear bright features persistently appeared on ENVISAT ASAR images as well as X-SAR images along the tidal channels in Gyung-Gi Bay, Korea during the ebb tides. These features are induced by spatial backscatter variations caused by surface convergence (divergence) through the interaction between tidal currents and bathymetry. In order to validate this mechanism, a numerical tidal model simulation is performed on the realistic bathymetry with the tidal boundary conditions. The tide model reproduces the current convergence zone along the tidal channel during the ebb tides, which exactly coincides with the location of bright line features on SAR images.

• 한국습지학회지
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• 제10권1호
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• pp.49-57
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• 2008

연안습지로 분류되는 갯벌은 육상과 해양을 연결하는 주요 전이대로서 다양하고도 고유한 생물상을 포함하면서 필수적인 생태적 기능을 수행하고 있다. 우리 인간을 포함하여 주변의 생물들이 누려왔던 갯벌의 생태계서비스 기능과 그것의 긍정적 효과를 유지 또는 강화하기 위해서는 갯벌의 보전이 매우 중요하나 국내의 경우 지금까지 보존보다는 개발이 우세하게 진행되어 왔다. 따라서 본 연구에서는 갯벌매립으로 인한 환경영향을 최소화할 수 있도록 해안개발사업으로 인한 갯벌훼손의 사례를 유형별로 분석하여 이를 토대로 저감방안을 수립하고자 하였다. 지금까지 해안개발사업을 추진하면서 입지선정단계에서 사업대상지가 갯벌로 구성되어 있다는 사실을 중요한 고려사항으로 인식하지 못하여 왔다. 이에 따라 1960년대 이래 우리나라 갯벌 면적의 거의 절반에 해당하는 갯벌이 매립되었고, 개발로 인해 주변 갯벌은 직 간접적으로 훼손되었으며, 모든 계획을 수립한 이후 환경영향평가의 협의단계에서 문제점이 지적되어 사업이 원래의 계획과는 다르게 수정해야 하는 경우도 나타나게 되었다. 이러한 문제점을 해결하기 위해서는 사업을 계획하는 초기단계에서 갯벌 환경에 대한 고려가 우선적으로 이루어져야 한다. 특히 입지선정단계에서 해양환경이 양호하여 다양한 생태계 기능을 수행하는 갯벌 (펄갯벌 및 모래갯벌)을 포함하여 암반 조간대, 사빈, 조하대 잘피숲 및 해중림 지역은 배제하도록 하여야 할 것이다.

• 한국습지학회지
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• 제8권3호
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• pp.51-65
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• 2006

연구지역에서 2003년 8월에 199개 정점에서 표층퇴적물을 채취하여 분석하였다. 표층 퇴적물은 6개의 퇴적상으로 구성되어 있었다. 일반적으로 모래 펄 퇴적물이 강화 남단 갯벌에서 우세하였고 모래 퇴적물은 강화도 서부의 수로와 조하대에서 우세하였다. 이 지역의 1997년 퇴적상과 비교하여 모래펄 퇴적물은 갯벌의 동쪽으로 확장 되었다. 강화 남단 갯벌과 주변부 30 정점의 표층퇴적물에서 살아있는 유공충 34종을 포함하여 총 61종의 유공충이 확인되었다. 살아있는 유공충에서는 Ammonia beccarii와 Elphidium etigoense, 전체군집에서는 Ammonia beccarii, Elphidium etigoense, Jadammina sp.와 Textularia earlandi가 연구지역에 넓게 분포한다. 일반적으로 개체수와 종 다양성은 갯벌의 서부에서 상대적으로 높은 수치를 나타냈다. 전체 유공충 군집의 집괴분석 결과 4개의 생물상으로 구분되었다. 생물상 1은 강화 남단의 동부 갯벌, 생물상 4는 강화 남단의 서부 갯벌의 저서환경을 나타냈다. 생물상 3은 생물상 1과 4의 전이환경으로 보여 진다.

• 한국지형학회지
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• 제25권1호
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• pp.31-45
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• 2018

This study investigated the characteristics of sedimentary environment changes across a tidal flat in Gagyeongju of Anmyeondo Island. We performed a spatio-temporal analysis on the grain sizes composition of sediments and micro-landform changes during the winter from 2013 to 2016. The results showed that erosion was a dominant processthroughout the study flat, reducing the surface elevation even by 1 m around the upper sand flat. As a consequence, headlands have formed in the entire region of Gagyeongju village. In addition, erosion quickly progressed along the low-lying subtidal zone and tide way and, in contrast, sedimentation progressed in the mid-elevation tidal flat. We posit that a jetty, which had been constructed as a pier facility on the eastern part of the study area, interfered with the flow of tidal current, thereby enhancing these erosional processes. This is because such interference can block the supply of fine-textured sediments from the nearby Cheonsu Bay and therefore reduce surface elevation. According to the surface sediment analysis, the sediments were categorized into 7 sedimentary facies, and generally displayed a high ratio of silt and clay. The result of time-series analysis (2012-2013) showed that the sediments on the tidal flat became fine-grained, and that sorting became worse. However, the sediments on the subtidal zone, embayment and along inside of the jetty tended to be coarse-grained. In conclusion, the tidal flat microlandform change in the study area was caused by a disruption in the seawater circulation due to the jittery construction within the tidal flat, which had a direct effect on erosional and sedimentary environment processes.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2005년도 학술발표회 논문집
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• pp.1053-1057
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• 2005

The occurrence probability (OP) distributions of tide levels using harmonic constants of six tidal gauging stations in Korean coastal zone were estimated and analysed in detail. OP analysis using harmonic constants data of Incheon(Youldo), Mokpo, Yeosu, Pusan, Pohang and Sokcho was carried out and compared with the OP using hourly tidal elevation data which were served through the Internet Homepage by the National Ocean Research Institute. The tidal elevation data were divided by the AHHW (ALLW) value referenced to MSL in order to compare the OP patterns in a relative scale. The OP of the tidal elevation calculated using 38 harmonic tidal constituents relatively well agreed with those of hourly observed tidal elevation data. However, the OP results using four harmonic tidal constituents overestimate the occurrence probability at the peak points and underestimate at the tail-regions of the OP. Especially, the OP patterns of the Sokcho and Pohang tidal gauging stations on the East Sea show totally different patterns and the estimation method using four harmonic constants should be modified and application should be strictly limited on the East Sea areas. The OP patterns are considerably well generated in case of the OP generation using the additional two or three dominant tidal constituents,