• Proceedings of the Korean Information Science Society Conference
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• 2002.04b
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• pp.202-204
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• 2002

디지털 지형 모델은 크게 세가지로 구분되는데 이들을 이용하면 여러 가지 분석 작업을 할 수 있다. 그 중 하나인 TIN은 데이터 양이나 계산의 정확도 면에서 커다란 장점을 가진다. 그런데 TIN을 구성하고 있는 삼각형이 기형적인 모형을 하고 있거나 분석 작업에 필요한 정보가 제대로 구성되지 않으면, 정확한 분석 작업을 수행 할 수가 없다. 특히 등고 데이터로부터 점 데이터를 추출해 TIN을 구성하게 되면 그러한 현상이 두드러지게 나타난다. 본 논문에서는 TIN을 생성할 때 이러한 단점을 보완하기 위해 좋은 TIN이 가져야 하는 속성을 나열하고 그러한 속성을 가질 때 어떤 점에서 좋은지 서술하고자 한다.

• Journal of the Korean Association of Geographic Information Studies
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• v.14 no.3
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• pp.174-187
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• 2011

The flowed soil is able to be estimated from topographic data of before and after the debris flow. However, it is often difficult to obtain airborne LiDAR data before the debris flow area. Thus, this study tries to develop a topographic restoration method that can provide spatial distribution of flowed soil and reconstruct the topography before the debris flow using airborne LiDAR data. The topographic restoration method can express a numerical formula induced from a Gaussian mixture model after extracting the cross sections of linear or non-linear in debris flowed area. The topographic restoration method was verified by two ways using airborne LiDAR data of before and after the debris flow. First, each cross section extracted from the debris flow sites to restore the topography was compared with airborne LiDAR data of before the debris flow. Also, the topographic data produced after the topographic restoration method applied to the debris flow sites was verified by airborne LiDAR DEM. Verifying the results of the topographic restoration method, overall fitting accuracy showed high accuracy close to 0.5m.

• 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 Korean Association of Geographic Inforamtion Studies Conference
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• 2008.10a
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• pp.173-174
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• 2008

해안 침식이 진행되고 있는 부산 해운대 해수욕장을 중심으로 해수면 상승에 따른 해안선 변화에 대한 분석을 실시하였다. 1947년부터 2008년까지 항공사진을 활용하여 해안선을 추출하였는데 사진촬영시간에 따라 해안선의 위치가 현저히 변화하기 때문에 위치만으로는 비교할 수 없고, 평균적인 해안선 부근의 경사와 촬영시의 조수상태를 고려한 수심별 해빈 면적 산정 공식을 활용하여 해안선 면적을 구하였다. 또한 조위자료를 통하여 40년 동안의 해수면 상승량을 산출하고, 이를 바탕으로 미래의 해안선 후퇴거리를 계산해 보았다. 그 결과 3008년도 해빈 면적은 1947년도와 비교하면 약 29% 면적이 감소하였고, 1992년도에는 일시적으로 해빈 면적이 상승하는데 이는 양빈 사업으로 인한 것으로 이후 다시 감소현상을 보인다. 그리고 조위자료 분석 결과 해수면은 연평균 2.462mm/year의 속도로 상승하였다.

• Korean Journal of Construction Engineering and Management
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• v.17 no.5
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• pp.71-77
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• 2016

Solar energy is a viable source to replace fossil fuels. However, challenges associated with site selection for solar panel installation inhibit the uptake of solar energy systems. Expressway slopes offer a potentially attractive alternative for solar panel installation for the following reasons: expressway slopes are vacant public sites, they are abundant (about 4,193km in South Korea), and they are linear in nature. Traditoinally when selecting sites for solar systems conventional surveying methods are employed. Unfortunately, these methods can be dangerous, time consuming, and labor intensive. To overcome these limitations of conventional site selection methodologies, we propose an automated approach using numerical maps. First, contour and expressway polylines are extracted separately from numeric maps. The extracted contour lines are then converted into a digital terrain model; this is used to calculate aspect and slope information. Next, the extracted expressway lines are projected onto a binary image and refined to recover the disconnections, and then applied to create a buffer zone to narrow the search space. Finally, all data sets are overlaid to identify candidate sites for solar panel systems and are visually verified through comparisons with aerial photos.

• Proceedings of the Korea Water Resources Association Conference
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• 2016.05a
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• pp.169-169
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• 2016

농업 유역 내 수문 순환 및 비점오염원의 발생 및 거동에 대해서 유역단위로서의 많은 연구가 진행되어 왔다. 하지만 유역단위로서의 모의를 통해서는 필지 별 발생되는 농업 비점오염물질을 평가하고 대책을 세우기에는 한계가 있다. 따라서 농업 유역의 농경지를 대상으로 유역단위 모의가 아닌 필지단위 모의를 진행함으로써 농업 비점오염물질에 대한 관리를 해야 할 필요성이 있다. 그리하여 본 연구에서는 필지단위로 상세한 모의가 가능한 ArcAPEX 모형을 사용하였으며 모형 내 임계값 조정을 통한 유역 구분 시 우리나라 지형 및 농업특성 상 지형인자 추출의 어려움으로 Pre-defined Streams and Watersheds 기능을 활용하는 것이 농경지를 대상으로 정확한 필지 분할 및 필지 특성 반영이 될 것이라 판단하였다. 하지만 Pre-defined Streams and Watersheds 기능에 필요한 자료를 구축하는데 시간과 노력이 많이 소모되고 어려움이 있었다. 따라서 본 연구에서는 입력 자료 구축의 편의를 도모하고자 Subarea-Stream 자동 연결 모듈을 개발하여 그 활용성을 평가하고자 하였다. 이를 위해 지형적 특성으로 인해 집약적인 농업이 행해지고 있는 강원도 양구군에 위치한 해안면 유역의 농경지 경계와 하천 및 수로에 대한 자료를 Subarea-Stream 자동 연결 모듈에 입력하여 최종적으로 Pre-defined Streams and Watersheds 기능에 필요한 입력 자료를 변환시켜 모형에 적용하였다. 본 연구결과 Pre-defined Streams and Watersheds 기능에 필요한 입력 자료를 단시간에 편리하게 구축할 수 있었으며, 농경지를 대상으로 필지 단위로 분할이 된 것을 확인 할 수 있었다. 최종적으로 본 연구를 통해 지형인자 추출 오류로 인해 수계 추출 시 나타날 수 있는 문제점에 대한 해결을 할 수 있었으며 모형 내 Pre-defined Streams and Watersheds 입력 자료 구축 시 Subarea-Stream 자동 연결 모듈을 활용한다면 농업 유역 내 농경지에 대해서 편리하게 유역단위에서의 모의가 아닌 필지단위에서의 상세한 모의를 하는데 큰 기여를 할 것이라 판단된다.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.10
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• pp.1082-1089
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• 2006

This study describes a methodology to develop a environmental and geographical information system for managing a national scale which is supports the environmental fate modeling. This system was developed via the integration of environmental and geographical information database(DB) and the DB usage software. For the sound environmental management, the DB were constructed by extracting the geometrical figures-such as points, polylines, and/or polygons-based on the geographical information previously developed in Korea. Then it was connected with the environmental information. Based on the Visual Basic Complier, the software can be a useful tool for visualizing the DB, for searching the environmental & geographical information, and supporting the environmental fate modeling.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.29 no.4
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• pp.343-349
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• 2011

Seabed topography and marine site survey should be performed first in the design and construction of marine structures. We could successfully acquire the seafloor topography information can be obtained by bathymetric survey and side scan sonar and the sediment layer thickness and 3D bedrock depth by seismic reflection. It is necessary to apply carry out the integrated interpretation to each other in the ocean civil Eng. In this paper, we have obtained information on the sea bottom topography and water depth at the same time using interferometer technique and on the basement depth by seismic reflection. We have performed to assess the proposed method on the seafloor topographic survey with bedrock.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.18 no.1
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• pp.63-68
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• 2006

Time series of waterline changes during a flood/ebb cycle can be utilized for supplementary data for measuring bottom topography. The waterlines extracted from consecutive images are substituted for depth contours using water level data. The distances between contours are quantified through a rectification image process. This technique is applied to the Keunpoolan beach in the Daeijak Island near Incheon. A camera monitoring technique supported by natural water level changes produces bottom topography with high precision. It is also less time consuming and more economical. The technique also can be utilized effectively to the physical modeling f3r measuring bottom changes in the three dimensional basin.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2002.04a
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• pp.219-228
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• 2002

Because western sea on the shore development is threatening sea ecosystem by decrease of silt and large size land-reclamation work by industrialization causes surrounding weather change and sea change, generate much changes bottom of the sea topography and coastline. Also, is influencing to route for safe entry into port of ship, departure. Therefore, this research did 0m boundary line, anxiety 2m line which appear to coastline of land portion and the border of silt using sea base level of lowest low tone side that is base line that appear because of sea waves to basis data numerical value Tuesday, numerical value by divide drawing that is changed to 4 area and analyze change degree of new airport construction and new town development, seashore by western sea district along the coast development of tide embankment construction and so on and bottom of the sea recognize.