• 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.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.2D
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• pp.317-324
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• 2006

This study deals with the precise GPS data processing refer to ITRF2000 through the calculation of absolute coordinates of cadastral satellite station which were established by purpose of cadastral surveying. We used the Gipsy-Oasis II software developed Jet Propulsion Laboratory to estimate daily position of GPS stations with orbital and atmospheric parameters. Especially, we carried out ionospheric delay, tropospheric delay, data existence whether or not and quality control check of observation data during pre-processing. The standard deviation of absolute coordinates was determined better than ${\pm}4mm$ from GPS precise analysis. The RMSE of difference between the result of this study and existing result by using Bernese s/w shows ${\Delta}X={\pm}0.079m$, ${\Delta}Y={\pm}0.019m$ and ${\Delta}Z={\pm}0.031m$.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.10a
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• pp.239-239
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• 2003

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.14 no.2
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• pp.181-188
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• 1996

Geodetic Satellite Positioning Techniques (NNSS, Transit, Doppler, VLBI, SLR etc.) still have much difficulty in surveying and necessity of point positions is being amplified in korea. Therefore some research institutes have being investigated point positioning using the GPS. In this study, 1 arranged the theory deal with point positioning using GPS carrier beat phase of dual frequency and estimated corrections of errors that be included in GPS observable. Also, 1 determined point position by the differencing scheme of GPS carrier phase, and analyzed the accuracy of point position. 1 suggested potentiality of geodetic point positioning using GPS carrier phase by comparing result of relative positioning with result of point positioning and analyzing result of network adjustment fixed any point position.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.3
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• pp.56-62
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• 2017

As the need for 3D spatial information increases, many local governments and related industries are establishing map-based 3D spatial information services and offering them to users. In these services, positional accuracy is one of the most important factors determining their applicability to specific tasks. This study studied the location correction method between indoor and outdoor 3D spatial information through the construction of modeling data on a BIM/GIS platform. First, we selected the sites and processed the BIM/GIS data construction with 3 steps. When connecting the BIM model including indoor spatial data and 3D texturing model based on ortho images, mismatches occurred, so we proposed a location correction method. Using the conversion algorithm, the relative coordinate-based BIM data were converted to the absolute positions and then relocated by means of the texturing data on the BIM/GIS platform.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.34 no.1
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• pp.79-90
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• 2016

The study has purposed in evaluating experiences for achievable accuracy and precision of time series at 3-D coordinates. It has been estimated from the kinematic medium-range baseline processing of Continuously Operating Reference Stations (CORS) for the potential application of crustal displacement analysis during an earthquake event. To derive the absolute coordinates of local CORS, it is highly recommended to include some of oversea country references, since it should be compromised of an observation network of the medium-range baselines within the length range from tens of kilometers to about 1,000 kilometers. A data processing procedure has reflected the dynamics of target stations as the parameter estimation stages, which have been applied to a series of experimental analysis in this research at the end. From the analysis of results, we could be concluded in that the subcentimeters-level of positioning accuracy and precision can be achievable. Furthermore, the paper summarizes impacts of satellite ephemeris, data lengths and levels of initial coordinate constraint into the positioning performance.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2003.04a
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• pp.88-93
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• 2003

국토공간정보의 기반인 수치지도 제작을 위해서는 위치에 대한 정확한 정보가 요구되며 이러한 정보는 GPS를 이용한 방법이 대표시 되고 있다. 우리나라도 GPS를 이용한 위치결정 방법의 효율성과 정확성을 확보하기 위해 전 국토에 걸쳐 24시간 위성데이터를 취득할 수 있는 70여개의 GPS 상시관측소를 설치 운영하고 있다. 따라서 본 연구는 GPS 상시관측소 데이터의 효과적인 활용 방안을 모색하기 위해 행정자치부와 국리지리원에서 설치 운영하며 호남권에 위치한 5곳의 상시관측소를 대상으로 각기 고정위치를 달리하여 기선해석과 망조정을 수행하여 고정위치에 따른 3차원 절대좌표의 정밀도를 분석하였다. 현재 행정자치부의 3곳의 상시관측소 절대위치는 고시되지 않아 국립지리원 고시 성과를 기준으로 고시성과와 계산성과의 3차원 절대 좌표를 비교하였다.

• 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.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.2
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• pp.175-181
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• 2010

This paper presents the dynamic analysis method for estimating the performance of flat-type blades in wiper systems. The blade has nonlinear characteristics since the rubber is a hyper-elastic material. Thus, modal coordinate and absolute nodal coordinate formulations were used to describe the dynamic characteristic of the blade. The blade was structurally analyzed to find the bending characteristics of the cross section of the blade. According to the analysis results, the blade section is divided into three deformation bodies: rigid, small, and large. For the small deformation body, the modal coordinate formulation is used, while the absolute nodal coordinate formulation is used for the large deformation body. To verify the dynamic analysis result, an experiment was performed. The simulation and experiment results were compared to verify the flexible multi-body dynamic model.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.05a
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• pp.165-165
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• 2004

정밀한 3차원 좌표측정을 위한 삼차원좌표측정기(Coordinate Measuring Machine)는 광학 스케일이나 헤테로다인 레이저 간섭계를 이용해서 x, y, z 축의 좌표를 측정한다. 이 경우 측정 정밀도에 가장 큰 영향을 주는 요인은 아베 오차(Abbe's error)이다. 인공위성용 광학계를 비롯해서 첨단 산업부품에 이르기까지 현재의 3차원 좌표측정은, 높은 정밀도와 대영역 측정을 동시에 요구하는 추세이다. 대영역으로 갈수록 _아베 오차의 영향은 더 커지므로 보다 근본적인 해결책이 필요하다.(중략)