• Journal of the Korean Society of Marine Environment & Safety
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• v.19 no.2
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• pp.111-118
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• 2013

This paper suggested the improvement of marine environmental impact assessment in eastern coast as analyzing consultation on the coastal area utilization for development of ports and fishing harbors for 3years in the east coast. The results of survey are only 3cases, 12cases and 16cases each for ocean currents, wave and sounding data. However, for development of ports and fishing harbors in eastern coast, ocean characteristics in eastern coast different than in the West Sea, South Sea is considered to marine environmental impact assessment. For development of ports and fishing harbors in east coast where the influences of ocean currents, wind-driven current and waves are dominant, the effect of the current should be considered to improve the reproducibility of tidal current. The wave should also be considered as an assessment criteria to obtain the validity of project such as harbor tranquility, functionality of breakwaters and stability. In addition, sediment inflow in river and exact water depth data of the ocean should be applied to numerical modeling and set wave-induced current to external force of sediment transport to predict the problems such as the harbor siltation and the coastal erosion considering ocean characteristics in the east coast.

• Geophysics and Geophysical Exploration
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• v.10 no.1
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• pp.77-88
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• 2007

Following a successful bathymetric mapping demonstration in a previous study, the potential of airborne EM for seafloor characterisation has been investigated. The sediment thickness inferred from 1D inversion of helicopter-borne time-domain electromagnetic (TEM) data has been compared with estimates based on marine seismic studies. Generally, the two estimates of sediment thickness, and hence depth to resistive bedrock, were in reasonable agreement when the seawater was ${\sim}20\;m$ deep and the sediment was less than ${\sim}40\;m$ thick. Inversion of noisy synthetic data showed that recovered models closely resemble the true models, even when the starting model is dissimilar to the true model, in keeping with the uniqueness theorem for EM soundings. The standard deviations associated with shallow seawater depths inferred from noisy synthetic data are about ${\pm}5\;%$ of depth, comparable with the errors of approximately ${\pm}1\;m$ arising during inversion of real data. The corresponding uncertainty in depth-to-bedrock estimates, based on synthetic data inversion, is of order of ${\pm}10\;%$. The mean inverted depths of both seawater and sediment inferred from noisy synthetic data are accurate to ${\sim}1\;m$, illustrating the improvement in accuracy resulting from stacking. It is concluded that a carefully calibrated airborne TEM system has potential for surveying sediment thickness and bedrock topography, and for characterising seafloor resistivity in shallow coastal waters.

• Journal of the Korean earth science society
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• v.34 no.2
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• pp.120-135
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• 2013

To investigate the changes in depositional environment around Gangneung Harbor, we analyzed the surface sediment textural parameters and topography data collected five times from February 2007 to February 2009. In the study area, sediments were mainly composed of sand and its sediment size became finer at offshore sites. During summer time, however, the sand grains became coarser than winter season near Namhangjin Beach, inside the harbor, and offshore areas. On the other hand, the grain size of Anmok Beach showed a gradual finer trend with time. Compared with the previous studies conducted before the completion of Gangneung Harbor construction, the mean grain size became finer on Anmok Beach, while it was coarser on Namhangjin Beach. The bathymetric changes observed over a 2-year period showed predominant erosion in the area of 5 to 10 m water depths and deposition in 2 to 5 m water depths. The shallower area less than 2 m water depths showed an alternating trend and yet slightly more dominant erosion process. The sediment textural parameters and the distribution of erosion and deposition have changed continuously. Results imply that such changes show long-term trends as well as seasonal variations in which the trend may have been formed after the completion of Gangneung Harbor construction.

• Proceedings of the Korea Water Resources Association Conference
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• 2018.05a
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• pp.77-77
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• 2018

한국 건설기술연구원의 하천실증연구센터는 기존에 불가능했던 준 실규모 하천실험, 생태실험, 치수분야 대형 모형실험 및 하천관련 기준수립을 위한 치수분야 수요와 하천 구조물의 품질성능평가 등을 목적으로 설립된 대규모 하천실증연구센터이다. 안동 하천실증연구센터는 총면적 $193,051m^2$의 부지에 하천의 일반적인 형상을 갖고 있는 완경사, 급경사, 만곡수로가 있으며, 수리량 측정 실험을 위한 초음파 유속계, 프로펠러 유속계, 전자식 유속계 등의 유속 측정 장비를 보유하고 있고, Total Station, Lidar, RTK-GPS 등 지형 측량에 사용할 수 있는 장비들도 보유하고 있어, 하천관련 실험을 수행하기에 충분한 여건을 보유하고 있다. 하천실증연구센터는 2013년부터 내 외부활용에서 활용할 수 있도록 지원을 수행하였으며, 총 118건의 하천 수리 및 생태분야, 지반분야 등 다양한 토목분야의 연구자들이 하천실증연구센터를 방문하여 실험을 수행하였고, 국내 기관 및 대학뿐만 아니라 미국의 Iowa 대학, Idaho 대학, USGS, 네덜란드 Deltares, 프랑스 Irstea 등 외국의 대학 및 기관에서도 방문하여 실험 및 공동연구를 수행하였다. 안동 하천실증연구센터의 활용 범위와 활용 건수가 지속적으로 증가함에 따라 자체적인 검토 및 외부의 의견에 따라 센터의 실험시설에 대한 개선이 필요한 사항이 발생하게 되었다. 하천실증연구센터의 수로는 기존의 지반위에 성토를 하여 인공적으로 건설하였기 때문에 일반적인 실내의 실험수로와는 다르게 하상에서의 침투가 발생하며, 이에 따라 하류방향으로 흐름이 진행될수록 유량의 변동이 발생하게 된다. 이에 따라 침투로 인해 발생하는 유량의 변동이 하도 유량 공급의 안정화에 미치는 영향에 대한 신뢰성 검증의 필요성이 필요하다고 판단되어 펌프에서의 유량 공급 및 하도내에서의 유량 안정화에 대한 검증 실험을 수행하고자 한다. 유량 공급에 대한 검증 실험은 크게 두 단계로 구성하였다. 첫 번째 단계는 펌프의 유량 공급에 대한 검증실험을 수행하고, 두 번째 단계에서는 동일한 조건내에서 하류의 지하수 수심, 공급수조의 수심, 하도내의 수심과 ADV 및 ADCP로 측정된 유량과의 관계를 통해 하도내의 유량이 얼마나 일정하게 공급되고, 하류방향으로 갈수록 유량 손실의 경향에 대한 실험을 계획하였으며, 전체적인 실험은 장기적으로 각 수로에 대하여 수행하는 것을 목표로 하였으며, 본 실험단계에서는 완경사 수로를 대상으로 하였다.

• Information and Communications Magazine
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• v.34 no.6
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• pp.73-79
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• 2017

해마다 증가하고 있는 피서철 해수욕장 안전사고 및 비선박 사고의 감소를 위해 본고에서는 연안해역정밀조사 자료를 활용한 해양안전지도의 제작 및 체감형서비스를 구축하여 서비스하는 방안을 마련하였다. 해양안전에 관련한 각종 자료를 수집, 현장조사, GPS측량, 전문가 및 현지주민의 인터뷰 등을 통해 취득하였다. 서비스에 이용될 기본 배경지도로는 5m급 육상 지형기복도와 국립해양조사원의 수심자료를 사용한 해저지형기복도를 융합하여 제작, 이용하였다. 각종 해양안전관련 정보들은 해양영토(구역), 어촌양식, 항로, 각종사고이력, 시설, 위험요소 등 해양안전과 관련한 총 26종의 다양한 분류체계를 구성하여 구축하였다. 이렇게 수집, 구축된 기본 해양공간정보들을 바탕으로 사용자에게 정보의 전달성을 고려하여 국민이 간접적으로 체감할 수 있는 형태의 사이트(해수욕장 등)별 도면 형태의 해양안전지도를 제작하고, 개방형 대국민 해양공간정보 웹서비스인 '개방해(海)', 해양전문 공공기관용 웹서비스인 '공유해(海)' 대국민 해야안전정보 앱서비스 안전해(海)'와 시스템들을 구축하여 서비스 방안을 구축하였다. 각 서비스에는 해양안전사고 예방을 위한 각종 안전 및 위험정보 콘텐츠들을 수록하였고, 목적에 따라 이용가능한 분석 기능들을 제공하였으며, 위험구역에 노출될 경우 사용자간 위험을 알려주는 알림 기능 등을 제공함으로써 위험에 노출되고 조치하는데 도움을 줄 수 있도록 하였다. 그 결과, 현재 각종 기관에서 해양공간정보의 이용을 확대하고자 연계신청 증가와 더불어, 대국민 서비스 이용자수가 증가하는 실적을 기록하였으며, 향후 보다 광범위한 영역에서 안전사고, 안전대응, 안전관리 등의 분야에서 대책 도구로 활용이 가능할 것으로 기대된다.

• Proceedings of the Korea Water Resources Association Conference
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• 2018.05a
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• pp.222-222
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• 2018

최근 이상기후로 인한 집중호우의 증가로 인해 하천의 홍수방어능력을 초과하는 침수피해가 급증하고 있다. 특히, 제주도는 태풍의 길목에 위치하고 있는 강우량이 약 2,061mm에 달하는 우리나라 최다우 지역으로 평시에는 건천인 상태의 하천이 집중호우 시 급격한 유출 발생으로 하류도심지역에 하천 범람으로 인한 많은 피해가 발생하고 있다. 제주도에서는 이를 방어하기 위해 하도 내 첨두 홍수량을 조절하여 하류지역의 피해를 경감시키기 위한 구조물인 저류지를 상류에 설치하여 운영하고 있다. 하지만 저류지의 건설을 통한 실제 홍수조절효과에 대한 정량적인 분석은 미흡한 실정이다. 이에 본 연구에서는 태풍 '나리' 때 가장 큰 피해가 발생한 한천의 한천1, 2 저류지를 대상지역으로 선정하여 2차원 수치모형인 Nays2d Flood 모형을 활용한 한천 저류지의 운영에 따른 홍수조절효과를 분석하였다. 지형자료는 드론을 활용하여 측정된 약 7cm 간격의 정밀한 하상 측량자료를 사용하였고, 태풍 '차바' 발생 시 계측된 저류지내의 수심 측정 센서 자료를 활용하여 모형의 검보정을 수행하였다. 보정된 모의결과를 활용하여 태풍 '차바' 때의 저류지가 활용되는 모습을 재현할 수 있었고, 이를 통해서 현재 설치된 저류지의 구조적인 문제점과 운영방법에 따른 홍수조절효과 개선방안을 제시하고자 하였다. 또한 저류지 설계 시 사용된 100년 빈도의 설계 홍수량을 바탕으로 모의를 수행하여, 기존에 제시된 한천저류지의 홍수 저감량과의 비교를 통해서 실제 저류지의 운영에 따른 홍수조절효과를 정량적으로 분석하였다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.5D
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• pp.533-540
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• 2010

Dam is very important facility in water supply and flood control. Therefore study needs to analyze reservoir capacity accurately to manage Dam efficiently. This study compared time series reservoir capacity using multi-dimensional spatial information to Chungju Dam reservoir and major conclusions are as follows. First, LiDAR and multi beam echo sounder survey were carried out in land zone and water zone of Dam reservoir area. And calibration process was performed to enhance the accuracy of survey data and it could be constructed that multi dimensional spatial information which was clearly satisfied with the standard of tolerance error by validation with ground control points. Reservoir capacity by water level was calculated using triangle irregular network from detailed topographic data that was constructed by linked with airborne LiDAR and multi beam echo sounder data, and curve equation of reservoir capacity was developed through regression analysis in 2008. In the comparison of the reservoir capacity of 2008 with those of 1986 and 1996, the higher water level goes, total reservoir capacity of 2008 showed decrease because of the increase of sediment in reservoir. Also, erosion and sediment area could be analyzed through calculating the reservoir capacity by the range of water level. Especially the range of water level as 130.0~135.0 which is the upper part of average water level, showed the highest erosion characteristics during 1986~2008 and 1996~2008 and it is considered that the erosion of reservoir slant by heavy rainfall is major reason.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.4C
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• pp.137-145
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• 2011

The amount of material upheaved owing to the installation of a granular compaction pile (GCP) in the seabed was analyzed by a field execution. The amount of material upheaved was predicted by existing equations, proposed by the Korea Construction New-Technology Association (KCNET; 2003) and Shiomi and Kawamoto (1986), and compared with the amount measured by bathymetry in the field. As a result, the upheaval heights were found to show a clear increase with increasing replacement ratio. The measured amount was larger than the amount predicted by the equations, but the amount predicted from the equation proposed by KCNET (2003) was relatively close to the measured amount. The upheaval heights were found to be more sensitive to the replacement ratio than the installation depth. The increasing trends of the upheaval heights with the installation depth as predicted by the equation of KCNET (2003) were in agreement with the measured trends at a replacement ratio of 25%. As a result of comparing the coefficients of upheaval by the equations, the coefficients of upheaval determined by the equation of KCNET (2003) were larger than those determined by the equation proposed by Shiomi and Kawamoto (1986), which were relatively close to the measured trends. Specifically, the difference between results obtained by both these equations was large when the replacement ratio was relatively low.

• Journal of the Korean Association of Geographic Information Studies
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• v.17 no.4
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• pp.28-39
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• 2014

Several studies have been performed globally on the construction of integrated systems that are available for the integrated use of 3D geographic information on terrain and oceans. Research on 3D geographic modeling is also facilitated by the application of Lidar surveying, which enables the highly accurate realization of 3D geographic information for a wide area of land. In addition, a few marine research organizations have been conducting investigations and surveying diverse ocean information for building and applying MGIS(Marine Geographic Information System). However, the construction of integrated geographic information systems for both terrain and oceans has certain limitations resulting from the inconsistency in reference systems and datum levels between two data. Therefore, in this investigation, integrated geospatial information has been realized by using a combined topographical map, after matching the reference systems and datum levels by integration of airborne Lidar data and multi-beam echo sounder data. To verify the accuracy of the integrated geospatial information data, ten randomly selected samples from study areas were selected and analyzed. The results show that the 10 analyzed data samples have an RMSE of 0.46m, which meets the IHO standard(0.5m) for depth accuracy of hydrographic surveys.

• The Journal of the Korea Contents Association
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• v.16 no.4
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• pp.442-454
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• 2016

Recently, due to the increment of national income and the living standard of citizens, the leasure business has been dramatically expanded. Among the business, inland water activities such as cruise tour or water taxi have drawn attention from the people. As more people come for a new pleasure, the frequency and the number of services continues to rise yet the safety of people values less recently. In fact, the number of relating accidents also has risen accordingly. In order to prevent such accidents in inland waters, the vessels' real time voyage data, the advanced warning system and the emergency rescuing system are required. In this paper, we have developed navigation guiding application for safety of passengers and vessels in inland waters. Navigation guiding applications not only provide Inland Electronic Navigational Chart(IENC) and vessel information but also allows communication between traffic service center and nearby vessels in case of an emergency situation. In order to implement Navigation guiding applications, developing Inland Electronic Navigational Chart was inevitable. Therefore, IENC of Han River, has developed based on measuring the water depth using multi-beam echo sounder system.