• Proceedings of the Korea Water Resources Association Conference
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• 2003.05a
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• pp.513-516
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• 2003

• Journal of the Korean Association of Geographic Information Studies
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• v.10 no.4
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• pp.14-21
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• 2007

In general bathymetric surveying is the method which gets depth. The water depth on chart is generally measured by a 200Khz frequency echo-sounder. In this study the thickness of the floating silt-clay was measured by a duel frequency sounder using 33Khz and 200Khz. This study shows the method of measuring the volume of the floating silt-clay in dredged basins dredged basin. After this surveying RI test was performed for verifying the existence of the silt-clay.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2010.04a
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• pp.403-406
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• 2010

Shoreline Investigation Survey in Korea 2001 Taean ended 2009 Tongyeong with start, Gosung in 2010 to survey the shoreline plans to complete the survey. Shoreline Investigation Survey of the country shape formulation and accurate coastline produced to by 2007 baseline survey, level survey, the terrain level survey, water level survey, tidal observations, property survey, etc was conducted. Since 2007 the status of topography survey were performed by replacing the Airborne LiDAR survey. In this research study surveying the shoreine of the business status, issues, improvements in the updated plan to analyze the shoreline land department future research and surveying the shoreline Island department plan is presented.

• Journal of Korean Society for Geospatial Information Science
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• v.24 no.1
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• pp.3-8
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• 2016

Due to the recent technical development and the enhancement of image resolution, Unmanned Airborne Vehicles(UAVs) have been used for various fields. A low altitude UAV system takes advantage of taking riverbed imagery at small rivers as well as land surface imagery on the ground. The bathymetric data are generated from the low altitude UAV system. The accuracy of the data is analyzed along water depths, comparing GPS observations and a DSM generated from UAV images. It is found that the depth accuracy of the geospatial data below 50 cm depth of water satisfies the regulation(${\pm}10cm$ spatial accuracy) of bathymetric surveying. Therefore this research shows that the geospatial data generated from UAV images at shallow regions of rivers can be used for bathymetric surveying.

• Journal of the Korean Association of Geographic Information Studies
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• v.21 no.3
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• pp.119-126
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• 2018

In this study, In this study, the Datum Level-based hydrography surveying system and the ellipsoid-based system were analyzed to acquire more consistent depth data. For the study, the ellipsoid-based surveying for hydrography was conducted twice for the same track line. And the depth was calculated by correcting rise and fall of water level (water level change by tidal energy and other marine environmental energies) respectively by the traditional water level correction method and ellipsoidally referenced water level correction method. there is able to check that Ellipsoid-based hydrographic surveying data is more improved than Datum Level-based hydrographic surveying data in aspect of level difference phenomenon in the same area (surveying line). This result shows that if the Ellipsoid-based hydrographic surveying is performed, the sea level change (tidal energy and other marine environmental energy) of the survey area in real time could be reflected to more consistent generating bathymetric data.

• Journal of the Korean Association of Geographic Information Studies
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• v.26 no.1
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• pp.56-68
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• 2023

A system that extracts seabed topographic information by simultaneously and continuously observing the horizontal position and water depth in the sea by combining a single beam echosounder and GNSS was constructed. By applying the developed system to actual measurements of small-scale sea areas, the effectiveness of bathymetry and sea-floor topographic data acquisition using GNSS and echosounder was examined. By using the developed outdoor program DS-NAV and indoor program DS-CAD and applying the tide level data at the time of actual measurement of the target sea area, it was possible to derive bathymetry results based on the datum level i.e. approximate lowest low water level(A.L.L.W). By using the developed outdoor program DS-NAV and indoor program DS-CAD and applying the tide level data at the time of actual measurement of the target sea area, it was possible to derive the results of bathymetric survey based on the datum level. From database built through the actual measurement. it was possible to create 3D model of the sea-floor topography and extract cross-sections. The results of this study are expected to be economically useful for extracting seabed topographical information from small sea areas or in dredging sites for offshore construction.

• Proceedings of the Korea Water Resources Association Conference
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• 2019.05a
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• pp.68-72
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• 2019

대하천사업으로 4대강에 다기능보 건설 및 대규모 준설이 이루어졌으며, 그 과정을 통해 인위적으로 변화된 하천지형은 시간이 경과함에 따라 유사공급과 유수흐름 등 다양한 요인들의 복합적 영향 하에서 지속적 변화과정을 거치게 된다. 따라서 하천의 효율적인 운영 및 관리를 위해서는 하천지형에 대한 연속적인 측정 및 분석을 통해 하천유로의 지형학적 특성과 그 변화의 양상과 정도를 파악하는 것이 필요하다. 본 연구에서는 낙동강 중 하류 구간에 대하여 음향측심기를 이용한 수심측량을 통해 유로의 지형정보를 취득 분석하여 다기능보 건설 후 유로의 지형학적 특성에 있어서의 변화 양상을 파악하고자 하였다. 이를 위하여 취득된 지형자료를 활용하여 유로 단면에 대한 기하학적 특성치들을 통한 형태학적 분석을 실시하였다. 또한 대하천사업 준공시 취득된 측량성과정보와의 비교를 통해 지형변화 양상과 정도를 파악하였다. 이를 통 해 대하천사업 이후 낙동강 중 하류 구간 유로의 지형변화 양상과 규모를 파악할 수 있었으며, 대하천사업 이후 준공측량성과를 기반으로 고시된 하천기본계획 상 지형정보의 정확성에 대해 평가할 수 있었다. 본 연구의 공간적 범위가 낙동강 중 하류 중 일부 구간들에 제한되었기에, 향후 본 연구에서 제안한 방법론을 활용한 지형특성 및 변화의 양상과 규모에 대한 지속적인 평가가 필요할 것으로 판단된다.

• Journal of Advanced Marine Engineering and Technology
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• v.34 no.4
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• pp.560-566
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• 2010

Port of Samcheonpo, designated as a Trading Port, is constructing New Port for the increase in trade and the requirement of maritime safety is growing. To meet these requirement for maritime safety, hydrographic surveying around south sea area of Samcheonpo using Multibeam Echo Sounder(MBES), DGPS etc was conducted. In this study, major item of hydrographic surveying such as sounding data was acquired and analyzed depth data comparing with vertical uncertainty in the special publication for hydrographic minimum specification published in Feb, 2008 by International Hydrographic Organization. By analyzing the depth data with 3 steps procedure, the port and starboard beam by removing the outskirts of the data processing could improve the efficiency and accuracy. The error of south sea were about 0.2m and the upper central part of the error were within 0.2m. Depth data of the study area are included in the 99% of 1st order and satisfied with a 100% tolerance of special order based on the international hydrograhic survey standard. This study will be a good case to support efficient decision-making for safe navigation, coastal management.

• Journal of Korean Society for Geospatial Information Science
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• v.10 no.1 s.19
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• pp.27-35
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• 2002

The dam made reservoir, a major means to overcome the problems caused by water resource's uneven supply by time and space, plays an important role, particularly, of water supply. The role of water supply will get more important, considering the usage of water resource becomes more intensive. Therefore, it is continuously required to construct new dams securing water supply and to study on effective operation plans of the dam. The size of reservoir needs to be measured according to possible supply estimation in the pre-design stage. The depth of water, at this point, should be taken. Among many ways of sounding, echo sounding has been frequently used recently. This study, therefore, presents a new way of sounding that takes less time with stronger accuracy, uniting GPS and echo sounder to apply a means of obtaining three dimensional position data. This enables the designer to escape from the conventional way of sounding in the estimation of reservoir to design and redesign a new dam.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.22 no.1
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• pp.58-66
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• 2010

In this paper, we have constructed high-resolution topographical map of macro-tidal Malipo beach through integration of terrestrial LiDAR measurement and MBES survey data at inter-tidal zone. To acquire the enough information of inter-tidal zone, we have done terrestrial LiDAR measurement mounted on the roof of vehicle with DGPS through go-stop-scan method at the ebb tide and MBES depth surveying with tide gauge and eye staff measurement for tide correction and MSL calculation at the high tide all together. To integrate two kinds of data, we have unified the vertical coordination standard to Incheon MSL. The mean error of overlapped inter-tidal zone is about 2~6 cm. To verify the accuracy of terrestrial LiDAR, RTK-DGPS measurement have done simultaneously and the difference of Z value RMSE is about 4~7 cm. The resolution of Malipo topographical map is 50 cm and it has constructed to DEM (Digital Elevation Model) based on GIS. Now it has used as an input topography information for the storm-surge inundation prediction models. Also it will be possible to use monitoring of beach process through the long-term periodic measurement and GIS-based 3D spatial analysis calculating the erosion and deposition considering with the artificial beach transition and coastal environmental parameters.