Precision Analysis of Digitized Cadastral Map Using Delaunay Triangle Coordinate Transformation

• Main Authors: Chen-Ming Hung, 陳明宏
• Other Authors: Ching-liang Tzeng
• Format: Others
• Language: zh-TW
• Published: 2008
• Online Access: http://ndltd.ncl.edu.tw/handle/62920201056806336955

碩士 === 國立成功大學 === 地球科學系專班 === 96 === Applying the cadastral maps drawed during the Japanese colonial period in the current land survey correction could be distracting due to inconsistent of coordinate systems. Accuracy of land survey correction results seems to be somehow controvertible for general land owners. In the reservation of cadastral maps, maps usually could not be jointed with whole areas but only reluctantly jointed partially. This study is based on Taiwan digital cadastral map from the ministry of the interior, using third-class satellite control points, reliable state points from land survey correction of land offices, and road central piles as the common points to build up Delaunay triangulation for affine transformations. Transforming old cadastral maps from TWD67 system to the new framework of TWD97 coordinate system to proceed common boundary point positioning, land parcel length, and area accuracy analysis. The result of this research showing that, coordinate transformation result is better while using third-class satellite control points with reliable state points to construct Delaunay triangulation from the testing densely area of urban constructions, with point positioning root mean square deviation of RMS(εN）±19.5cm and RMS(εE）of ±21.9 cm. When increasing reliable state point as conditions, acute angle in Delaunay triangulation should be avoided. The mistakes from old cadastral maps are caused by historical causes, and current corrections still can not recover 100% of its original states. The quality of surveyors, current actual land usage, disputions and other factors could all effect the coordinate transformation result of Delaunay triangulation. Even though it can not fully satisfy the accuracy of urban boundary surveying numerical method, but it can still be provided as the references for lead process of land survey correction. How to apply digital cadastral map results and improve land survey correction accuracy in order to accord with current regulations and practical needs will remain as the arduously goal.