• 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 the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.35 no.6
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• pp.509-516
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• 2017

In cadastral surveying, there are problems that no area error is allowed where numerical surveying is carried out, and allowable area error is specified irrespective of parcel shape where graphic surveying is carried out. In this research, we derived a general formula of parcel area error necessary for grasping these two problems. The calculations using the derived formula showed that where the coordinate error of the boundary point is set to 5cm+10ppm practically, then even a small parcel of $100 m^2$ includes non-negligible area error of $0.71m^2$. And, it is found that the area error specified by the current egulation is based on a rectangular parcel of 1:5 aspect ratio. These results show that the area error of polygon parcel can be determined by a single formula by specifying the coordinate error of the boundary points, and can be used to revise the current regulations that can be applied uniformly regardless of surveying methods.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.16 no.1
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• pp.9-15
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• 1998

Numerical cadastral surveying method has advantages of higher accuracy and less individual error than planetable surveying method if we consider the result of surveying at the same area. Now in the areas where they use numerical cadastral records, coordinate is the basis when the boundary location is registered in numerical cadastral re-cords or is reconstructed on land surface, and this coordinate represents simply the absolute locational relationship with respect to origin point. But when we register the cadastral boundary location in cadastral or reconstruct it on land, relative relationship with respect to traverse point is more advisable basis than absolute relationship with respect to orgin point. This study contributes to the numerical cadastral surveying by discussing the problems to be improved that the principle of coordinate based boundary location registration and reconstruction has.

• Journal of Korean Society for Geospatial Information Science
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• v.18 no.3
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• pp.105-114
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• 2010

This study considers and analyzes the position and area errors and the related problems through the experimental study of the converting process from the cadastral coordinate system to the global coordinate system. Also, based on the result, the points of improvement have been considered. According to the conversion of the coordinates in the study area, the standard deviations for the conversion of coordinates in regard to every parcel boundary point (478 points in total) have been calculated as X=0.0079m and Y=0.0153m respectively. It can be considered that such values are extremely excellent. Also, after analyzing the area errors, it has been found that there is a difference of $0.062m^2$ on average. Such a difference stays within the range of the allowable error tolerance specified by the current laws. Therefore, in regard to the limited area which is subject to the study, it can be concluded that the difference is not great in differences of the position or the area. As a result, the converting process into the global coordinate system is possible.

• 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 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 Korean Society for Geospatial Information Science
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• v.24 no.4
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• pp.39-45
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• 2016

In this study, with arbitrary reference points on the water, photogrammetry accuracy analysis was conducted using unmanned aerial vehicle(UAV). A small reservoir is a research area, and twenty buoys were used as arbitrary reference points. Errors of location coordinate were identified with control of amounts of used reference points. cases are categorized by index scores per photos. Accuracy of X is 0.141m~0.166m and accuracy of Y is 0.136m~0.241m. Considering that allowable error for the maritime boundary survey is ${\pm}2m$, it is possible to get the accuracy data available for the photogrammetry of UAV using an reference point. In addition, the coefficient of correlation between the number of reference points per unit and number of buoys used as reference point and the ratio of the reference point per square measure, and percentage of buoys used as reference point and the coefficient of x and y were performed. Each element, x, and y showed a strong correlation and the coefficient of number of buoys used as reference point was irrelevant. The results of this correlation analysis can be analyzed that the number of reference points used in each picture is greater than the actual number of reference points used in location accuracy.

• Journal of Korean Society for Geospatial Information Science
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• v.7 no.2 s.14
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• pp.47-56
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• 1999

In this study, tie point observation in aerial triangulation was automated by the image processing methods. The technique includes boundary extraction and We matching processes. The procedures were applied to extract points of Interest and to find their conjugate points in the other images. The image coordinates of the identified points were then used to compute their absolute coordinates. An algorithm was developed in this study for the automation of observation in aerial triangulation, which is a manual process of selecting a tie point and recording the image coordinate of the selected point. The developed algorithm automates this process through the application of a mathematical operator to extract points of interest from an arbitrary image. The root m square error of image coordinates of the developed algorithm is $6.8{\mu}m$, which is close to that of the present analytical method. In a manual environment, the accuracy of the result of a photogrammetric process is heavily dependant on the level of skill and experience of the human operator. No such problem exists in an automated system. Also, as a result of the automated system, the time spent in the observation process could be reduced by a factor of 61.2%, thereby reducing the overall cost.

• Proceedings of the KSR Conference
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• 2007.11a
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• pp.1141-1151
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• 2007

In this paper through Honam 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 21cm to 40cm diminishing to a gentle straight line, distortion of X axis varies 14cm to 29cm. Through a revision, the deviation value between the coordinates were 6mm to 9mm and it satisfied the allowable error of national geographic information institute which is following ITRF (International Terrestrial Reference Frame) and cadastral boundary survey(10cm). consequently the coordinate conversion is possible using railroad control points as common control points.