Digital Terrain Models Precision Assessment and Applications - Example of Houshanyue Landslides

• Main Authors: Yu-Jui Chao, 趙宥睿
• Other Authors: Kuo-Jen Chang
• Format: Others
• Language: zh-TW
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/73gr52

碩士 === 國立臺北科技大學 === 土木與防災研究所 === 100 === Recently, the natural calamities due to the climate change and torrential rain during typhoon season have been threatening the safety of local resorts and the residents’ lives. It is difficult to analyze the change to the area’s landform by using 5m DTM for small-scale shallow landslides which occur in this area. In addition, Houshanyue is devoid of related data on the change of landform before and after disasters. Based on above reasons, the research is aimed at structuring a 2m DTM consisting of the landform before and after landslides, and the rebuilding by exploiting aerial image and positioning system with precise LIDAR coordinates loaded to measure control point and mobile Remotely Piloted Vehicle image data. Furthermore, according to the Digital Terrain Model (DTM), the Precision Control Index is used to evaluate the DSM Average Vertical Error, Standard Deviation, Worse Maximum, and Worse Minimum, forming Error Normal Distribution whose Peak Graph help us ensure that the accuracy is in ideal condition. The range of evaluation includes the whole area, slide land and skirts of the slide land to find the difference among three sections. We compare the variations of altitude from 2005 to 2010 by constructing DSM analyzing topographic change in every period and using the search function of Arc Map obtaining Surface Elevation of longitudinal section and transverse section. Besides, orthoimage is also exploited to detect the range of wood erosion.