• KSCE Journal of Civil and Environmental Engineering Research
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• v.42 no.5
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• pp.689-699
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• 2022

Recently, high productivity capabilities have been improved due to the application of advanced technologies in various industries, but in the construction industry, productivity improvements have been relatively low. Research on advanced technology for the construction industry is being conducted quickly to overcome the current low productivity. Among advanced technologies, 3D scan technology is widely used for creating 3D digital terrain models at construction sites. In particular, the 3D digital terrain model provides basic data for construction automation processes, such as earthwork machine guidance and control. The quality of the 3D digital terrain model has a lot of influence not only on the performance and acquisition environment of the 3D scanner, but also on the denoising, registration and merging process, which is a preprocessing process for creating a 3D digital terrain model after acquiring terrain scan data. Therefore, it is necessary to improve the terrain scan data processing performance. This study seeks to solve the problem of density inhomogeneity in terrain scan data that arises during the pre-processing step. The study suggests a 'pixel-based point cloud comparison algorithm' and verifies the performance of the algorithm using terrain scan data obtained at an actual earthwork site.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2002.04a
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• pp.279-280
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• 2002

본 연구에서는 라그랑지안 확산모델(LDM; Lagrangian dispersion model)을 이용하여 평지 및 언덕지형에서의 연기확산을 수치모사하였다. 수치예측의 검증을 위하여 평지지형의 경우는 풍동실험 결과와 비교하고 언덕지형의 경우는 오일러리안 확산모델(EDM; Eulerian dispersion model)의 모사결과와 비교함으로써 언덕지형에서 오염물질의 확산특성을 연구하였다. (중략)

• Journal of the Korean earth science society
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• v.32 no.2
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• pp.190-199
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• 2011

A photovoltaic energy map that included a topography effect on the Korean peninsula was developed using the Gangneung-Wonju National University (GWNU) solar radiation model. The satellites data (MODIS, OMI and MTSAT-1R) and output data from the Regional Data Assimilation Prediction System (RDAPS) model by the Korea Meteorological Administration (KMA) were used as input data for the GWNU model. Photovoltaic energy distributions were calculated by applying high resolution Digital Elevation Model (DEM) to the topography effect. The distributions of monthly accumulated solar energy indicated that differences caused by the topography effect are more important in winter than in summer because of the dependency on the solar altitude angle. The topography effect on photovoltaic energy is two times larger with 1 km resolution than with 4 km resolution. Therefore, an accurate calculation of the solar energy on the surface requires high-resolution topological data as well as high quality input data.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.17 no.4
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• pp.393-401
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• 1999

Non-point source pollution poses a serious threat to river. therefore non-point pollution model was developed. This non-point pollution model requires detailed spatial data for accurate predictions Geo-spatial Information System(GSIS) is well suited to those needs. The parameters for these models provided by the GSIS were slope, slope shape, field slope length and SCS run off curve number. Hence, this study presents an application of GSIS processing tools for AGNPS model developed by the ARS(Agricultural Research Service) in cooperation with the MPCA(Minnesota Pollution Control Agency) and has developed interface that construct the input data of ASCII type in the AGNPS model using GSIS.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2008.06a
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• pp.254-259
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• 2008

지형의 표고값물 격자간격으로 표현하는 수치표고모델(DEM)은 지형분석을 위한 GIS데이터 활용과 휴대전화 중계안테나의 영향권 분석, 정밀지오이드 계산을 위한 지형효과계산 등 여러 가지 분야에 활용되고 있다. 본 연구에서는 이렇게 활용성이 증가하고 있는 수치표고모델을 수집하고 또 진주시 지역을 대상으로 LiDAR촬영을 통한 LiDAR 수치표고모델을 구축하여 그 정확도를 분석하고자 하였다. 연구에 활용된 수치표고모델은 GTOPO30, SRTM-3, 지형도(1/50,000) 독취 DEM, 환경부 DEM, 항공사진에 의해 생성된 DEM, 그리고 LiDAR DEM의 6가지이며, 정확도 분석을 위해 GPS측량과 수준측량이 동시에 실시된 409점의 진주시 3차원 도시기준점 성과를 이용하였다.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.7 no.2
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• pp.7-19
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• 1989

The developments in remote-sensing, digital mapping, and automation of land information system have provided the impetus for the increasing use of Digital Terrain Models in engineering planing and design. In this paper, an evaluation is made on tile method of accurate earth-volume determination in computerized road design using by Digital Terrain Models. The result of numerical test shows that the $BL_{in}$-1 Model is the most efficient model in Earth-volume determination of road design.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.34 no.5
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• pp.1463-1476
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• 2014

In order to understand hydrodynamic and morphodynamic characteristics under wave-current interactions in an estuary, a coupled model for two-way analysis between existing 3-d numerical wave tank and newly-developed 3-d morphodynamic model has been suggested. Comparing to existing experimental results it is revealed that computed results of the newly-suggested model are in good agreement with each laboratory test result for wave height distribution, vertical flow profile and topographical change around ocean floor pipeline in wave-current coexisting field. Also the numerical result for suspended sediment concentration is verified in comparison with experimental result in solitary wave field. Finally, it is shown that the 3-D coupled Hydro-Morphodynamic model suggested in this study is applicable to morphological change under wave-current interaction in an estuary.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.25 no.1
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• pp.55-62
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• 2007

Recent advances in airborne LiDAR technology allow rapid and inexpensive measurements of topography over large areas. The generation of DTM/DEM is essential to numerous applications such as the fields of civil engineering, environment, city planning and flood modeling. The demand for LiDAR data is increasing due to the reduced cost for DTM generation and the increased reliability, precision and completeness. In order to generate DTM, measurements from non-ground features such as building and vegetation have to be classified and removed. In this paper, a segmented morphology filter was developed to detect non-ground LiDAR measurements. First, segments LiDAR point clouds based on the elevation. Secondly classifies those protruding segments into non-ground points. Those non-ground points such as building and vegetation are removed, while ground points are preserved for DTM generation. For experiments, data sets used in Comparison of Filters (ISPRS, 2003) depicting urban and rural areas were selected. The experimental results show that the proposed filter can remove most of the non-ground points effectively with less commission and omission errors.

• Geophysics and Geophysical Exploration
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• v.27 no.1
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• pp.37-50
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• 2024

The magnetotelluric (MT) survey can be affected by external environmental factors. In particular, when acquiring MT data in islands, it is essential to consider the combined effect of topography and sea to understand the results and make accurate interpretations. To analyze the MT response (apparent resistivity, phase) with consideration of the effect of topography and sea, a small cone-shaped island model surrounded by deep sea was created. Two-dimensional (2-D) and three-dimensional (3-D) forward modeling were performed on the terrain model considering topography and the island model considering both topography and sea. The 2-D MT response did not reflect the topographic and sea effect of the direction orthogonal to the 2-D profile. The 3-D MT response included topographic and sea effects in all directions. The XY and YX components of the apparent resistivity were separated on undulating topography, such as a hill. A conductor at 1 km below sea level could be distinguished from topographic and sea effects in the MT response, and low resistivity anomaly was attenuated at greater depths. This study will facilitate understanding of field data measured on small islands.

• Water for future
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• v.18 no.2
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• pp.143-152
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• 1985

A method is suggested for the reappearance of a surface runoff hudorgraph of a river basin by linking the hydrologic response of a catchment represented by the instantaneous unit hydrograph(IUH) with the Horton's empirical gemorphologic laws. The geomorphologic theory of the IUH developed by G. Itrube et al. and the geomorphoclimatic theory of the IUH developed by Bras et al. are used to derive the new hydrologic response function in consideration of geomorphologic parameters and climatic characteristics by applying to Sukekawa's rainfall-runoff model. The derived response function was tested for on some observed hydrographs in a natural watershed and showed promising, and by considering a drainage basin as m(1∼4) identical linear reservoir in series, it was founded that the model(m=2) is most applicable to predict hydrologic response regardless of the size of basins. A modelization algorithm of a basin using Sthahler's ordering scheme of drainage network will give good result in analysis of the surface runoff huydrograph by the method of this study.