圖解數化地籍圖之伸縮改正及實測接合研究

A Study of Digitized Map Sheets Stretching and Shrinking Correction and Sheets Merging Through Field Survey

圖解地籍圖數值化工作，已於94年度全部完成，其成果之整合應用，為目前重要課題。圖解數化僅保存數化當時地籍圖之精度，地籍圖因破損、伸縮等自然或人為因素造成圖幅無法銜接之問題，無法藉由圖解數化解決。又圖解數化完成後，多數地政事務所土地複丈作業仍採圖解法局部套圖作業，造成相鄰複丈地區之成果，各自形成獨立系統，有難以接合情形，且其施測成果無法建檔再利用，造成外業測量工作之重複，並因而影響複丈測量作業之速度與精度。本項研究主要探討圖解數化地籍圖伸縮改正及不同坐標轉換方式對套疊現況成果之影響，以改善圖解地籍圖品質，並建立約制條件坐標轉換模式，提供日後實施電腦套圖之參據。經研究結果，地籍圖改正以四參數成果較佳，套疊現況時，則以六參數成果較佳。先實施地籍圖改正後再進行現況套疊、圖幅接合及與現況點之差異比較結果，較未改正地籍圖之精度均有明顯提升。 The programs of graphic cadastral map digitization in Taiwan had been finished until 2005. The integrated applications have become more important issue currently. The accuracy of the cadastral boundary lines was kept with fidelity to the existing map situation during digitization. For areas seriously damaged, stretched or shrunk result into adjacent map sheets cannot coincide with each other. The problems of nonconformity of boundary lines have not been solves thereafter. After digitization, graphic land revision was still performed in many land administration offices. It resulted with connections being harder and harder because of different regional system. Surveying data gathered during land revision period cannot be reuse in consequent survey work of next land revision. The worse efficiency and accuracy of land revision survey are implicated. To discuss the influence of map sheets stretching and shrinking correction , and different coordinates transformation methods applying into the maps overlapping procedure, and try to build up the model of constraint conditions for coordinates transformation for development of automatic overlapping software, is the main purpose of this research. Upon the experiment, distortion correction of map sheets through Helmert transformation can get better result. Affine transformation applying on overlapping can get a better result . During the sheets distortion correcting and overlapping, almost 80% of the processes used Helmert and Affine transformation in turn. The accuracy has been promoted in map sheets distortion correction; the accuracy also has been promoted in adjacent maps merging; the accuracy has been promoted in the analyze of vertical distance. It means the correction of sheet distortion is benefit to the accuracy improvement.

The programs of graphic cadastral map digitization in Taiwan had been finished until 2005. The integrated applications have become more important issue currently. The accuracy of the cadastral boundary lines was kept with fidelity to the existing map situation during digitization. For areas seriously damaged, stretched or shrunk result into adjacent map sheets cannot coincide with each other. The problems of nonconformity of boundary lines have not been solves thereafter. After digitization, graphic land revision was still performed in many land administration offices. It resulted with connections being harder and harder because of different regional system. Surveying data gathered during land revision period cannot be reuse in consequent survey work of next land revision. The worse efficiency and accuracy of land revision survey are implicated. To discuss the influence of map sheets stretching and shrinking correction , and different coordinates transformation methods applying into the maps overlapping procedure, and try to build up the model of constraint conditions for coordinates transformation for development of automatic overlapping software, is the main purpose of this research. Upon the experiment, distortion correction of map sheets through Helmert transformation can get better result. Affine transformation applying on overlapping can get a better result . During the sheets distortion correcting and overlapping, almost 80% of the processes used Helmert and Affine transformation in turn. The accuracy has been promoted in map sheets distortion correction; the accuracy also has been promoted in adjacent maps merging; the accuracy has been promoted in the analyze of vertical distance. It means the correction of sheet distortion is benefit to the accuracy improvement.