• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2003.10a
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• pp.411-416
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• 2003

다목적 대형 댐의 건설로 수몰된 과거의 삶의 공간을 20년이 지나서 다시 복원한다는 것은 그곳에 살던 실향민 등에게는 참으로 반가운 소식이다. 본 연구에서는 1980년대 초에 완공된 충주댐으로 인하여 물 속에 잠긴 청풍 지구를 수몰이전의 입체 지형 공간적으로 원형복원하기 위한 원격탐사 기법을 적용한 것이다. 비교적 해상도가 좋은 인공위성 사진자료와 원격탐지된 디지털 영상자료를 수집하고, 수몰직전에 제작된 지형도를 이용하여 위성영상자료의 통합 적용하여 수몰이전의 지형공간정보를 현재시간으로 영상 복원하는 실험을 한 것이다. 이를 위하여 지형도에서 추출한 등고선과 현재의 등고선과의 접목을 통하여 청풍 주변지역을 중심으로 당시의 수치표고모형을 생성하였다. 또한 이를 입체적으로 보여주기 위한 투시조감도를 각 방향에서 생성함으로서 수몰이전의 아름다운 모습을 3차원적으로 영상복원 하였다. 좀더 가깝게 수몰마을을 보기 위한 최근접 시뮬레이션 동영상을 제작하여 과거 기억 속의 고향을 찾아볼 수 있도록 한 것이다.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.20 no.1
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• pp.13-19
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• 2002

In a different way of satellite image or aerial photo, the image acquired by terrestrial photogrammetry has to go through complicated management according to the desired precision and analysis range. In this study, digital surface model and ortho image for cultural asset, terrestrial structures, were made by reflectorless total station in order to increase the application of single photo, and that was analyzed and compared with the method using stereo image. Single photo is expected to be utilized as the measuring method for drawing cultural assets or examining the stability of slope in which high precision doesn't need by performing the various geometric and visual analysis using ortho image made by excluding the difficulties of acquisition and plotting of stereo image.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.1016-1019
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• 2009

Detailed survey of the rock mass is essential for design, construction and maintenance of rock slope. However, geological survey of poor outcrops and various geophysical aids provides limited information for slope engineering. Remote measurement system for excavation surface (Surface Mapper) and projection s/w for borehole data (Fracjection) are developed for further support of slope surveying. The Surface Mapper measures orientation of joint, fault, foliation on excavated rock surface and database the measured data. The Fracjection projects measurements in boreholes, which are obtained by BIPS, Televideo and DOM operation, to any expected excavation space. These methods promise new approaches for surveying, designing, constructing and maintaining processes of slope.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.16 no.2
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• pp.177-185
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• 1998

There is an increasing request for 3D data and outlines on building for urban planning and design. This paper describes an approach to extract building using Digital Surface Models(DSM) and stereo pairs of aerial images. DSM contain informations not only about the topographic surface like Digital Elevation Models(DEM), but also about buildings and other objects higher than the surrounding topographic surface, e.g. tees. We therefore describe our approach consisting of two step procedures. The first step of the approach is to generate DSM by stereo matching using Maximum Likelihood Estimation and Dynamic Programming. The proposed stereo matching is using the cost function for finding the disparity between the left and right image, and the Dynamic Programming for solving the stereo matching problem. The second step is to detect building outlines using the DSM and the edge informations extracted from a digital aerial image by Sobel Operator. The overlay analysis of the DSM and the edge information by Sobel Operator was efficient to detect building outlines.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.25 no.2
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• pp.157-163
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• 2007

Recently, industrialization of a country is accelerated and request of society infrastructure is raised so national land development is activity view. Accordingly, the search for a wide-ranging buried heritage do acted in large construction region. Because the buried heritage get buried in land that it is necessary to the precision search and research for a record and a preservation. Until now, Surveying techniques of a historic site have made status map, profile and cross section map through leveling survey, total-station survey and sketch of specialist. So, to solve problems existing relic survey or drawing making method have using digital camera these researches rapidly and economically obtain stereo image of object and present a technique that constructs 3D image model for digital photogrammetry method. Also, these researches construct 3D image model for record and preservation of a historic site through site test and in 3D and graphical express a historic site and support works that produce other maps if we need it. offer base data of GIS (Geographic Information System) to collect and analyze overall, information of a historic site.

• Tunnel and Underground Space
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• v.33 no.6
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• pp.495-507
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• 2023

The roughness of discontinuity significantly influences the mechanical characteristics of rock masses and extensively affects thermal and hydraulic behaviors. In this study, we utilized photogrammetry to generate 3D point cloud data for discontinuity and applied this data to characterize the roughness of discontinuity. The discontinuity profiles, reconstructed from the 3D point cloud data, were compared with those manually measured using a profile gauge. This comparison served to validate the accuracy and reliability of the acquired point cloud data in replicating the actual configurations of rock surfaces. Subsequent to this validation, influence of the number of profiles for representative JRC assessment was further investigated followed by suggestion of roughness anisotropy evaluation method with application of it to actual rock discontinuity surfaces.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.24 no.1
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• pp.123-130
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• 2006

The purpose of the paper is to make the three dimensional road simulation model based on the digital photogrammetry and GIS techniques in the middle of Halla mountain of Jeju island. To do this, we generate DEM (digital elevation model) and digital ortho image using GIS tools such as Arc View, Imagestation and MGE module. In GIS, the overlay map schemes combining of the hill shade, the land slope and aspect were applied. Based on the processes, we can build the best three dimensional road line along the hill side of the island. From the results, we also found that the derived DEM from digital ortho image and the GIS technique were very useful for choosing the best three dimensional road design before the real road construction works in Jeju island.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.4 no.1
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• pp.25-36
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• 1986

Minimum three pairs of model are necessary to determine absolute coordinates of three-dimensional objects. This paper researches the method of analyzing three-dimensional coordinates of all sides of objects by photographing a pair of stereo model through the medium of mirror. An objective lies in improving the accuracy and the efficiency of mirror images method by introducing an error correction function for distortion of the mirror. Projected-onto-mirror points are transformed on the object plane through mirror plane equation. As the result, X-coordinates error is the largest and Y, Z-coordinates error represents about 1mm. Also, accuracy can be improved by introducing correction function for left and right mirror and correcting the distortion of mirror.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.11 no.2
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• pp.7-15
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• 1993

In order to generate database, we need to obtain speedy and corret topographic information according to requisite purpose. Generally methods to an acquisition of topographic information are available by the use of maps, satellite images, stereo models of aerophoto and so forth. But we must choose a optimal method in consideration of area of object region, spatial solution of image, required accuracy and economic. Therefore, this study aims at providing the establish method of efficient topographic data base of small object region by means of spatial layer techniques of geo-spatial information system and using acquisition of geo-information and production method of base map with photoballoon system to obtain topographic information for reasonable plan and design of object region which select a zone preparation of a collective village with small region. As a result of this study, we decided an f-stop and a shutter speed of camera to obtain accurate stereo model and were able to obtain stereo photography and topography for small region by using of photoballoon system through accuracy analysis according to change flight height and air base speedly and economically. We can establish the data base useable to efficient plan and design as existence map with overlay plan drawing.

• Journal of Broadcast Engineering
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• v.18 no.1
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• pp.31-42
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• 2013

This paper proposes a photogrammetric rectification method based on Bayesian approach as a method that eliminates vertical parallax between stereo images to minimize visual fatigue of 3D contents. The image rectification consists of two phases; geometry estimation and epipolar transformation. For geometry estimation, coplanarity-based relative orientation algorithm was used in this paper. To ensure robustness for mismatch and localization error occurred by automation of tie point extraction, Bayesian approach was applied by introducing several prior constraints. As epipolar transformation perspective transformation was used based on condition of collinearity to minimize distortion of result images and modification for input images. Other algorithms were compared to evaluate performance. For geometry estimation, traditional relative orientation algorithm, 8-points algorithm and stereo calibration algorithm were employed. For epipolar transformation, Hartley algorithm and Bouguet algorithm were employed. The evaluation results showed that the proposed algorithm produced results with high accuracy, robustness about error sources and minimum image modification.