Abstract ▼ AI-Helper

GPS survey is the satellite surveying system to determine a location much more precisely in broad areas than the traditional surveying depending on angles and distances. However, permanent GPS station where GPS data can be obtained for 24 hours shall be installed and operated to effectively use GPS ...

GPS survey is the satellite surveying system to determine a location much more precisely in broad areas than the traditional surveying depending on angles and distances. However, permanent GPS station where GPS data can be obtained for 24 hours shall be installed and operated to effectively use GPS survey. In addition, the precise coordinates transformation factors are required to convert WGS84(World Geodetic System 1984) coordinates that is ECEF coordinates system to the current TM coordinates. When WGS84 coordinates is converted to the current geodetic coordinates using transformation factors in three variables that the National Geography Institute notifies, it is required to be very careful because of the deviations on the transformation results by area. This study divided the area into 5 sectors, set the transformation parameters and analyzed the transformation characteristics by variable to find out the method to utilize permanent GPS station and to determine more precise local transformation parameters in Gwangju and Jeonnam area. The major results of this study are described below. As a result of putting the baseline as fixing the permanent station, when the baseline exceeds 80km, the standard distribution and deviation for the baseline interpretation are increased so that the reliability is decreased. Therefore, it is proposed to limit the application scope in accordance with the baseline when determining three dimensional absolute position as fixing the permanent station and applying the baseline. This study determined and proposed WGS84 coordinates with high precision for the permanent stations in Yeonggwang, Suncheon and Jangheung where the absolute positions were not determined yet on the basis of the permanent stations in Gwangju and Jeonju. In addition, it proved that it was effective to determine WGS84 coordinates on triangle points on the basis of all permanent stations, to analyse its effectiveness and to apply the relative positioning as putting the permanent stations as the fixed points when determining the absolute coordinates for triangle points. It was verified that the transformation accuracy varied in accordance with the quality of effectiveness rather than the basic marks as comparing the transformation effects with the currentness of TM coordinates by area. This study compared and analysed the transformation accuracy by variable to convert WGS84 coordinates from.GPS to TM coordinates as applying 7 variables, 6 variables and 3 variables transformation to each area. As a result, the accuracy of the transformation using 7 variables was highest. Consequently, this study proposed more precise transformation parameters by area for Gwangju and Jeonnam area.

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