• Journal of Cadastre & Land InformatiX
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• v.45 no.2
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• pp.101-116
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• 2015

In Boundary Point Coordinate Register Area, the accuracy on Transformation of World Geodetic System(WGS) is determined by surveying results at the reference point. However, the present surveying result in reference points indicates the irregular performance due to the limitations of measurement techniques and methodologies, moreover, can be contaminated by various error sources from the unique characteristics of each project district and start time of the project. Therefore, the main purpose of present investigation is to conduct an inquest into error cause by project districts for each type in Boundary Point Coordinate Register Area, and propose the improvement plan of surveying accuracy through the WGS Transformation and verification-surveying.

• Journal of Cadastre & Land InformatiX
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• v.54 no.1
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• pp.103-115
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• 2024

Trilateral adjustment can complement the problem of transforming cadastral maps into World Geodetic Coordinate system. First, it is possible to determine adjusted coordinate of common points that match each other over a wide area. Second, calculations that focus on specific points can be performed. Third, a solution that maintains the shape of the regional network can be obtained through constraints. Thus, the point coordinates can be determined appropriately for the survey system. In addition, heterogeneous survey results that span regions with different coordinate origins can be calculated on a single origin coordinate. This improves the efficiency of the workflow in tranforming cadastral maps into World Geodetic Coordinate System.

• Journal of Korean Society for Geospatial Information Science
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• v.16 no.3
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• pp.79-85
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• 2008

This study aims to derive a practical coordinate transformation method for the existing geographic information database. After analyzing the status and problems of existing 1/1,000 digital base map and GIS application database, the transformation parameters are estimated and the accuracy of the transformation is determined based on the transformed coordinates. We analyzed the accuracy of a transformation using the published national transformation coefficients as well as the estimated local transformation coefficients using national and urban control points in a study area. In addition, the 1/1,000 digital base map from aerial triangulation is compared with respect to the coordinates of urban control points. Based on the comparison, the biases on the national control points which were used at the time of digital map generation was analyzed. Then, the accuracy of transformed coordinates based on the world geodetic system using local transformation coefficients estimated from urban control points are determined. We also analyzed the transformation accuracy of underground infrastructure database using the same transformation method as the case of 1/1,000 digital base map. Through this study, it was found that the estimation of transformation coefficients by Molodensky-Badekas using urban control points was suitable for a local government. Furthermore, it was obvious that the accuracy of a 2-dimensional affine transformation was comparable to that of 7 parameter transformation for a local area. Applying the coordinate transformation and bias correction, we could transform GIS application database which was built by an offset surveying based on digital base map within the transformation accuracy of 10 cm. Therefore, it was judged that there will not be a big problem on the transformation of the GIS DB to the world geodetic system.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.13 no.2
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• pp.117-124
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• 1995

The main purpose of the present study was to investigate coordinate transformation based on two different systems: one was the World Geodetic System 1984(WGS84) adopted as a reference system for GPS satellite surveying;and another was the current Korean geodetic system based on Bessel ellipsoid. For this purpose, three methods were used to determine 7 parameters as follows: Bursa-Wolf model, Molodensky-Badekas model, and Veis model. The coordinate transformation was carried out using simillity transformation applied the obtained 7 parameters and the precision of transformed coordinate was evaluated. From this results, we found that Bursa-wolf model is more suitable than others for the determination of transformation parameters in Korea.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.25 no.6_2
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• pp.613-623
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• 2007

The main purpose of this study is to investigate the coordinate transformation based on two different systems between local geodetic datum(tokyo datum) and international geocentric datum(new Korea geodetic datum). For this purpose, three methods were used to determine seven parameters as follows: Bursa-Wolf model, Molodensky-Badekas model, and Veis model. Also, we adopted multiple regression equation method to convert from Tokyo datum to KTRF. We used 935 control points as a common points and applied gross error analysis for detecting the outlier among those control points. The coordinate transformation was carried out using similarity transformation applied the obtained seven parameters and the precision of transformed coordinate was evaluated about 9,917 third or forth order control points. From these results, it was found that Bursa-Wolf model and Molodensky-Badekas model are more suitable than other for the determination of transformation parameters in Korea. And, transforming accuracy using MRE is lower than other similarity transformation model.

• Spatial Information Research
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• v.22 no.1
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• pp.35-43
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• 2014

The Triangle Mesh Warping method is suggested and applied in coordinate transformation to world geodetic system in this study. The common points of Uiwang city are used to compare the transformation accuracy of the suggested methods with existing national coordinate transformation methods. As a result, the Triangle Mesh Warping method was satisfied with accuracy criteria for positioning on a map larger than scale 1/1,000 with smaller number of common points and without distortion modeling. Additionally, in case of Guri and Pyeongtaek city that established the World Geodetic System, the suggested method generates the result of transformation accuracy better than 5cm. Based on the test, it was found that the suggested method improves the problem of securing many common points and reduces the problem of mis-match between the transformed data of adjacent areas. Accordingly, for transformation of large-scale topographic map, cadastral map, GIS DB and serial cadastral map to the World Geodetic System, it is judged that the Triangle Mesh Warping would be a good method for economical efficiency and accuracy using by minimum common point.

• 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 the Korean Society of Marine Environment & Safety
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• v.2 no.S1
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• pp.45-60
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• 1996

본 연구는 Bessel 측지계에서 WGS-84 측지계로 좌표변환할 경우 발생할 수 있는 우리나라 지형정보의 변동을 고찰한 것이다. 고찰 대상은 우리나라 지형형태와 독도와 일본의 오끼제도 사이의 거리로 하였다. Bessel 측지계에서 WGS-84 측지계로 좌표변환한 결과는 다음과 같다. 1). Mercator 도법에서, 임의로 선정한 정사각형의 우리나라 주변 지형은 고위도에서 축소되면서 부채꼴 모양으로 변형되는 결과를 나타내었다. 2). UTM 도법에서, 우리나라 남동부근 연안의 52S 지역중에서 임의로 선정한 정사각형 지형은 가로가 2m 축소되고, 세로는 1m 축소되었다. 3). Mercator 도법을 이용한 한국의 독도와 일본의 오끼제도 사이의 거리를 비교한 결과 오끼제도가 독도쪽으로 약 25.3m 근접하게 되는 결과를 나타내었다.

• Journal of the Korean Society for Railway
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• v.10 no.6
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• pp.685-691
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• 2007

In this paper through Honan high-speed railroad which is planned with the north and south axis, we will verify the feasibility of the coordinate conversion using railroad control points after regarding current planned-railroad as the linear central axises. From analysis, distortion of Y axis varies 21 cm to 40 cm diminishing to a gentle straight line, distortion of X axis varies 14 cm to 29 cm. Through a revision, the deviation value between the coordinates were 6 mm to 9 mm and it satisfied the allowable error of national geographic information institute which is following ITRF (International Terrestrial Reference Frame) and cadastral boundary survey (10 cm). consequently the coordinate conversion is possible using railroad control points as common control points.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.15 no.1
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• pp.29-39
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• 1997

The need of transformation parameters from local geodetic datums to a geocentric coordinate system is becoming more common, with the increasing application of satellite positioning techniques to LIS/GIS survey with cadastral management. In this paper, the national transformation parameters between the Korean geodetic coordinates which is based on the Bessel 1841 ellipsoid and the WGS84 ellipsoid are determined by the least square methods with weighted parameter constraints. Three-dimensional geocentric coordinates are based on GPS observation at 31 stations in the geodetic network, the datum parameters are computed within a standard deviation of less than 1 meter. In South Korea, the national transformation parameters with Bessel geoid-heights are useful for GPS baseline processing and for middle-scale map/database transformation.