• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.32 no.5
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• pp.505-513
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• 2014

The RapidEye can acquire the 6.5m spatial resolution satellite imagery with the high temporal resolution on each day, based on its constellation of five satellites. The image products are available in two processing levels of Basic 1B and Ortho 3A. The Basic 1B image have radiometric and sensor corrections and include RPCs (Rational Polynomial Coefficients) data. In Korea, the geometric accuracy of RapidEye imagery can be improved, based on the scaled national digital maps that had been built. In this paper, we present the fully automated procedures to georegister the 1B data using 1:25,000 digital maps. Those layers of map are selected if the layers appear well in the RapidEye image, and then the selected layers are RPCs-projected into the RapidEye 1B space for generating vector images. The automated edge-based matching between the vector image and RapidEye improves the accuracy of RPCs. The experimental results showed the accuracy improvement from 2.8 to 0.8 pixels in RMSE when compared to the maps.

• Journal of Korean Society for Geospatial Information Science
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• v.21 no.4
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• pp.101-107
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• 2013

Generally the commercial high-resolution images have their coordinates, but the locations are locally different according to the pose of sensors at the acquisition time and relief displacement of terrain. Therefore, a process of image co-registration has to be applied to use the multi-temporal images together. However, co-registration is interrupted especially when images include the cloud-covered regions because of the difficulties of extracting matching points and lots of false-matched points. This paper proposes an automatic co-registration method for the cloud-covered high-resolution images. A scale-invariant feature transform (SIFT), which is one of the representative feature-based matching method, is used, and only features of the target (cloud-covered) images within a circular buffer from each feature of reference image are used for the candidate of the matching process. Study sites composed of multi-temporal KOMPSAT-2 images including cloud-covered regions were employed to apply the proposed algorithm. The result showed that the proposed method presented a higher correct-match rate than original SIFT method and acceptable registration accuracies in all sites.

• Proceedings of the Korean Society of Computer Information Conference
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• 2012.07a
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• pp.301-302
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• 2012

본 논문에서는 웹 서버에 사진을 등록(upload)하면 서버에서 자동으로 사진의 메타데이터(EXIF)의 GPS정보를 추출하여 미리 정이된 정보와 비교하여 사진이 촬영된 장소를 표시하고, 좌표 값을 활용하여 구글 지도(google map)과 연계되는 방법을 제안한다. 사진등록으로 사용되는 서버 웹페이지로는 php를 사용하여 그림을 등록하고, exif_read_data함수를 사용하여 메타데이터에 접근하고 메타데이터 안의 GPS의 값을 추출하여 정의된 분류표에 의해 사진을 분류하고, 구글지도와 연계하여 촬영된 위치를 지도상에서도 확인할 수 있도록 하였다.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.29 no.3
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• pp.249-255
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• 2011

The free-stereo mosaics image without GPS/INS and ground control data can be generated by using relative orientation parameters on the 3D model coordinate system. Its origin is located in one reference frame image. A 3D coordinate calculated by conjugate points on the free-stereo mosaic images is represented on the 3D model coordinate system. For determining 3D coordinate on the 3D absolute coordinate system utilizing conjugate points on the free-stereo mosaic images, transformation methodology is required for transforming 3D model coordinate into 3D absolute coordinate. Generally, the 3D similarity transformation is used for transforming each other 3D coordinates. Error of 3D model coordinates used in the free-stereo mosaic images is non-linearly increased according to distance from 3D model coordinate and origin point. For this reason, 3D model coordinates used in the free-stereo mosaic images are difficult to transform into 3D absolute coordinates by using linear transformation. Therefore, methodology for transforming nonlinear 3D model coordinate into 3D absolute coordinate is needed. Also methodology for resampling the free-stereo mosaic image to the geo-stereo mosaic image is needed for overlapping digital map on absolute coordinate and stereo mosaic images. In this paper, we propose a 3D non-linear transformation for converting 3D model coordinate in the free-stereo mosaic image to 3D absolute coordinate, and a 2D non-linear transformation based on 3D non-linear transformation converting the free-stereo mosaic image to the geo-stereo mosaic image.

• Progress in Medical Physics
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• v.8 no.2
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• pp.19-26
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• 1997

3-dimensional Neuronavigator, Viewing Wand(ISG Technologies, Toronto, Cannda) is the surgery aid equipment for real time image (CT or MRI) guided surgery. The assurance of spatial accuracy of this system is important for clinical application. In this study, we have designed the acrylic brain phantom and measured the spatial error with that phantom. The phantom has designed to have capability to simulate image guided surgery. The phantom has 22 vertical rods whose diameters are 5mm and each rods has different length. CT scans were performed by 2.0mm slice and reconstructed for 3-Dimensional analysis. End point of rods can be obtained using reconstructed 3- Dimensional images and they are compared to actual position data. Average deviation was less than 2mm for various situations. Spatial error of Viewing Wand is acceptable in the clinical points of view, while cosmetics of the software needs to be modified to more user friend. Better accuracy can be expected when we apply the mixed fiducial fit registration and surface fit registration method. And even better results can be obtained if registration points distributed even and symetric around the target.

• Journal of Cadastre & Land InformatiX
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• v.45 no.1
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• pp.151-167
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• 2015

At present cadastral surveying is being driven fort combination of digitalized cadastral map accord with real cadastral boundary between cadastral resurvey area and World Geodetic System transformation about all country. So this study is conducted to newly establish items being needed in making digitalization of parcel boundary points based on the World Geodetic System in registration conversion surveying. For this study firstly management of mountainous districts Act, related laws and registration conversion-related laws and regulations are reviewd. Secondly, economical, administrative validation by using data from 12-branch companies of LX is analyzed. Thirdly, surveying method and procedure were established through experimental surveying on the two cases such as digital and analog area. Finally, through investigating standard of estimate about cadastral surveying, it was calculated amendment of registration conversion surveying fee based on World Geodetic coordinate System.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2003.04a
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• pp.65-68
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• 2003

국가기준점인 삼각점은 통일원점, 구소삼각원점, 특별소삼각원점으로 구분 설치하였으며, 이들은 설치기관, 시기, 방법, 측량단위와 원점 등이 모두 달라 측량성과가 같지 않으며 제각각 다른 자료체계로 등록되어 있다. 또한 삼각점들의 유지ㆍ관리 소홀로 실용성과에 한계를 드러내고 있으며, 최근 정밀1차기준점측량 성과를 고시하였으나 토지조사사업 당시의 성과와 많은 차이가 있어 지적측량의 활용에 많은 문제를 가지고 있다. 이러한 문제점을 파악하고 개선하고자 경기도 연천군 관내 삼각점과 지적삼각점에 대하여 GPS 관측을 실시하고 현행좌표로 변환하여 등록 자료와 비교 분석하고 이에 대한 문제점과 개선방안을 제시하였다.

• Journal of Cadastre & Land InformatiX
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• v.44 no.2
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• pp.139-153
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• 2014

The world geodetic system transformation of cadastral record have to minimize differences of boundary and area being in cadastral record according to transformation for that is direct connected with the land owner and property protection. However it is very difficult to accurately maintain the before and after transformation because coordinate transformation is generally using a mathematical conversion formula. At present, Helmert model by using 4-parameter is official coordinate transformation model for Cadastral Resurvey Project but scale factor is most sensitive to changes of area and relative position in the same parcel. In this study, it was proposed 3-parameter method using by scale factor fixing through the application of a Helmert in order to avoid changing the area difference and keeping the error within the tolerance range of the boundary which is related to the boundary point coordinate region.

• Journal of Cadastre & Land InformatiX
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• v.54 no.2
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• pp.5-18
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• 2024

To produce seamless cadastral maps through coordinate transformation, a correction that minimizes the boundary difference between neighboring zones or maps is required. In coordinate transformation, a technology that emphasizes specific common points in cadastral surveying was developed, and the usefulness of the perspective projection is presented as a technology to eliminate the coordinate difference between the adjacent four map points that occurs as a result of the coordinate transformation. The correction of the displacement of the vertice points and the map matching entail changes in the boundary line of the parcel, which changes the shape of the parcel and causes changes in the area of the parcel. Therefore, in order to ultimately ensure the consistency of the registered area and the coordinate area, the introduction of a numerical calculation method by the least square method is presented as a working method that can fine-tune the boundary points. The method of utilizing the Affine transformation, perspective projection, and boundary point refinement in conjunction improves the quality of the maps, which has been managed as an individual maps, and enables them to be created as a continuous map over the area.