• Journal of Ocean Engineering and Technology
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• v.33 no.6
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• pp.526-534
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• 2019

The average coastline and the erosion control line introduced as the management coastline, and the average shoreline (MSL) was established from the observed coastline. Also, the median grain size and the wave height of 30-years return period were applied. The erosion control line (ECL) was established through the model, HaeSaBeeN. These two lines set the coastline for evaluation. Based on the observed monitoring data along the coastline, the 1-day variation according to the normal distribution was used to estimate the regional variation, and the width of the erosion was calculated by applying the median grain size (D₅₀) and the wave height of 30-years return period through the high-wave coastal erosion width model, i.e., HaeSaBeeN.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.13 no.1
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• pp.1-8
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• 2001

Wave-induced currents drive nearshore transport processes, and hence an accurate understanding of wave-current interaction is required for proper management of coastal zone. This paper presents details of an adaptive quadtree grid based numerical model of the coupled wave climate and depth-averaged current field. The model accounts for wave breaking, shoaling, refraction, diffraction, wave-current interaction, set-up and set-down, mixing processes, bottom friction effects, and movement of land-water interface at the shoreline. The wave period- and depth-averaged governing equations arc discrctized explicitly by means of an Adarns¬Bashforth second-order finite difference technique on adaptive hierarchical staggered quadtree grids. Results from the numerical model are in reasonable agreement with the laboratory data of longshore current generated by oblique waves on a plane beach (Visser 1980, 1991).

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.29 no.6
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• pp.399-409
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• 2017

This study numerically investigates the characteristics of the velocity field including the average flow velocity, longshore current and turbulent kinetic energy acting as the main external forces of the salient formed behind the permeable submerged breakwaters. Shoreline response is also predicted by the longshore-induced flux. In this paper, a three-dimensional numerical wave tank based on the OLAFOAM, CFD open source code, is utilized to simulate the velocity field around permeable submerged breakwaters under the formation condition of salient. The characteristics of the velocity field around permeable submerged breakwaters with respect to the gap width between breakwaters and the installing position away from the shoreline under a range of regular waves for different wave height are evaluated. The numerical results revealed that as the gap width between breakwaters increases, the longshore currents become stronger. Furthermore, as the gap width becomes narrower, the point where flow converges moves from the center of the breakwater to the head part. As a result, it is possible to understand the formation of the salient formed behind the submerged breakwaters. In addition, it was found that the longshore currents caused by the gap width between breakwaters and the installation position away from the shoreline are closely related to the turbulent kinetic energy.

• Journal of the Korean Association of Geographic Information Studies
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• v.2 no.1
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• pp.1-11
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• 1999

The Korean government is developing a systematic plan of integrated coastal management for effective conservation, utilization, and development of coastal areas. For this plan, integrated maps of land maps and nautical charts are indispensable. However, these maps are not made, nor studied yet in terms of integration, although digital maps(DM) on land and electronic nautical charts(ENC) have been recently developed by Korean Geography Institute and National Marine Investigation Institute, respectively. In this study, as preliminary studies to make eventual integrated maps, the concept of coastal areas are defined, specifically, coastal lines from DM and ENC are matched against each other. Issues on map production procedures, coordinate systems, and map projections, are carefully considered. A test coastal area located in Seo-Gu, Pusan, over 14 km of coastal lines is selected for the edge matching of coastal lines. RMS differences are 13.83 m and 4.37 m over man-made coastal lines and natural coast lines, respectively, which are quite larger considering a scale difference and other factors. However, no systematic differences are found.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2008.06a
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• pp.461-464
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• 2008

연안에서의 태풍 해일에 의한 침수범람 지역 예측을 위하여 GIS를 통한 정밀 육도-해도 접합 및 분석을 만리포 해변을 대상으로 시범 수행하였다. 만리포 해변의 정밀 육도-해도 접합을 위하여 고해상도 지상 LIDAR 시스템의 시범 측량 자료와 국토지리정보원의 수치지형도, 국립해양조사원의 수치해도 수심자료 및 한국 주변해역의 30초격자 수심자료를 사용하였다. 또한 평균해수면 산정을 위하여 만리포에 설치된 수압식파고계 조위자료와 해변의 표척을 통한 목측 관측을 통한 조위자료를 활용하였다. 다양한 자료의 GIS 기반 육도-해도 접합 및 분석을 통한 정밀 지형도 구축 기술은 태풍 해일에 의한 침수범람 예측을 위한 정밀 격자 수치모델의 입력 자료로 활용되어 침수 범람 예측 결과의 재해도(Hazard Map) 작성이 가능하고, 나아가 침식 퇴적 등의 지속적인 해안선 변화 모니터링에 활용될 수 있다.

• Proceedings of the Korea Water Resources Association Conference
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• 2022.05a
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• pp.233-233
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• 2022

최근 기후변화로 인해 집중호우 및 돌발홍수의 증가로 침수피해가 빈번하게 발생하고 있다. 마찬가지로 해안지역의 피해 또한 증가하고 있으나, 해안지역의 특성을 고려한 연구가 미비한 실정이다. 따라서 본 연구에서 해안지역의 특성을 고려해 폭풍해일로 인한 월파뿐만 아니라 강우도 고려하여 해안지역의 범람 양상을 확인하고자 하였다. 본 연구에서는 국내 해안지역에 대한 빈도별 폭풍해일과 강우로인한 범람 모의를 진행하였다. 우선, 수치해석 모형의 경계조건을 산정하기 위해 EurOtop(2018)의 경험식을 이용하여 월파량을 산정하였다. EurOtop의 월파량 산정 시 암석 옹벽이 아닌 콘크리트 옹벽으로된 경사식 단면으로 고려하여 계산하였고 산책로와 벽까지 고려하여 계산하였다. 경험식 계산을 위해 매개변수(유의파고, 여유고, 구조물의 조도계수, 구조물의 기울기 및 경사 등)를 조정하여 계산하였다. 이 중, 계산에 사용된 유의파고는 시나리오별 강우에 대해 SWAN(Simulating WAves Nearshore)으로 계산된 값을 활용하였고, 해안선을 두 부분으로 나누어 해안지역 각 지점별 파고값의 평균을 사용해 월파량 계산을 진행했다. 이때, 파고의 종류로 5% 확률의 파고, 평균 파고, 중앙값 파고, 95% 확률의 파고로 분류해 월파량 계산을 진행했고, 그 중, 평균 파고를 이용해 계산한 월파량을 수치해석 모델의 입력자료로 활용하였다. 시나리오별로 계산된 월파량만을 이용해 2차원 침수모형인 FLO-2D의 경계조건 입력값으로 사용하여 침수 양상을 표출하기 위해 Mapper와 ArcGIS를 이용하여 침수와 범람 양상을 확인하였다. 또, 다른 조건으로 시나리오별 계산된 월파량, 연구유역 해안 반대편에 위치한 산으로부터 유입되는 물의 양 그리고 해안지역 전체에 내리는 강우를 입력자료로 사용해 모의를 진행한 후 Mapper와 ArcGIS로 표출하여 침수 및 범람 양상을 확인하였다.

• Proceedings of the Korea Water Resources Association Conference
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• 2009.05a
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• pp.1960-1963
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• 2009

본 연구에서는 부산시 용호만 해안대수층에서 전기전도도와 지하수위의 수직적인 관측을 통해, 조석에 의한 해수/담수 경계면의 변동을 산정하였다. 연구지역은 부경대학교 대연캠퍼스 기숙사 신축부지 주변 해안대수층이며, 응회질퇴적암과 안산암 및 안산암질 화산각력암 등으로 구성되어 있다. 관측공의 개발심도는 120 m, 케이싱심도는 19 m, 내경은 0.2 m, 관측공과 해안선의 이격거리는 180 m 정도이다. 전기전도도에 의해 산정된 밀도는 담수에서 997.58 $kg/m^3$, 해수에서 1020.36 $kg/m^3$ 이었다. 관측기간(2008년 8월 21일${\sim}$10월 18일) 동안 해수/담수 경계면의 변동 범위는 해수면 기준 -21.69${\sim}$-21.53 m 이었으며, 경계면의 평균 위치는 해수면 기준 -21.62 m 정도이었다. 해수/담수 경계면과 지하수위의 상관성은 매우 높게 나타났으며, 해안대수층 내 해수/담수 경계면의 변동은 조석의 일(고조, 저조) 및 보름(대조, 소조) 단위의 변동에 영향을 받고 있음이 확인되었다. 관측기간 동안 지하수위는 전반적으로 하강하는 경향을 나타내었으며, 이는 관측기간이 풍수기에서 갈수기로 전환되고 있었기 때문이다. 향후에는 지속적인 관측을 통해, 용호만 해안의 해수면 상승에 의한 내륙으로의 해수침투를 연구하고자 한다.

• Journal of The Geomorphological Association of Korea
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• v.20 no.1
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• pp.97-109
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• 2013

This study introduces an analysis of the quantitative characteristics of topography and topographical changes based on precise 3D topography through 6 times surveys from December 2008 to January 2010 using Terrestrial LIDAR on the Malipo beach. The Malipo sand beach is mostly located between 0m to 1.5m MSL. The area of the beach above 2.25m, the Mean High Water, is very small. It have characteristics of topographical change of erosion and deposition along the entire coast line which more apparently appear in the northern beach than the southern part of the beach. Erosion prevails from spring to autumn, while during winter both erosion and deposition largely occur. Volumes from first and last survey were almost equal.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2003.05a
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• pp.141-146
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• 2003

Time seres of suspended sediment concentration, surface elevation and velocity were measured and analysed to investigate the role of waves and the predominance of infra-gravity wave component for sediment suspension phenomena in the surf zone. For the investigation in detail, we adopted the cross spectral analysis method between sediment concentration and the characteristic values of wave, and ensemble average analysis method about long-period wave component, which is dominant to sediment suspension in the measurement point. The obtained results are summarized as follows: 1) The relationship between sediment concentration and the characteristic values of wave is stronger for the long-period standing wave components(about 60s and 30s) than the long wave components(about 100s), which have the most energetic power, 2) and also, it is cleared that sediment concentration is increased in the case of the phase, the velocity components of the first mode long-period standing wave(60sec) were accelerated toward on-shore direction, that is, the water surface in offshore side is higher than on-shore side.

• 한국해양학회지
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• v.22 no.2
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• pp.71-79
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• 1987

We studied the annual variation of water temperatures in the upper 200m off southeast coast of Korea by means of harmonic analysis of the temperatures at 10 standard depths of 51 stations. The distributions of the mean temperature in coastal zone are almost parallel to the coast, whereas those in offshore are almost zonal. With an increase of depth, the annual amplitude decreases nearly exponentially and the annual phase increases nearly linearly. The average e-folding depth for the annual amplitudes is 65m, vertical change of the annual phase is 180 per 200m, and the vertical eddy conductivity is $4\textrm{cm}^2/sec$. Annual variations of temperatures in the coastal zone of a few tens miles from the coast are considerably different from those in offshore area. The e-folding depths in coastal zone are shallower than those in offshore region, and the changes of phase with depths in coastal zone are smaller than those in offshore region.