The point cloud data obtained by airborne radar equipment has high-precision three-dimensional spatial data information, which provides a new technical means for making high-precision DEM. Although the production of l...The point cloud data obtained by airborne radar equipment has high-precision three-dimensional spatial data information, which provides a new technical means for making high-precision DEM. Although the production of lidar system hardware equipment is relatively mature, the existing data filtering and data interpolation algorithms have their own advantages and disadvantages, and it is difficult for any algorithm to meet the needs of various terrain classification. Therefore, the exploration of airborne radar technology point cloud data processing and application, and the development of more intelligent, accurate, and highly adaptable point cloud filtering algorithms are worthy of our attention and research, which are of great significance to improving the quality of DEM generation and the development and application of future airborne radar technology.展开更多
Geomorphological mapping plays a key role in landscape representation: it is the starting point for many applications and for the realization of thematic maps, such as hazard and risk maps, geoheritage and geotourism ...Geomorphological mapping plays a key role in landscape representation: it is the starting point for many applications and for the realization of thematic maps, such as hazard and risk maps, geoheritage and geotourism maps. Traditional geomorphological maps are useful for scientific purposes but they need to be simplified for different aims as management and education. In tourism valorization, mapping of geomorphological resources(i.e., geosites, and geomorphosites), and of geomorphic evidences of past hazardous geomorphological events, is important for increasing knowledge about landscape evolution and active processes, potentially involving geomorphosites and hiking trails. Active geomorphosites, as those widespread in mountain regions, testify the high dynamicity of geomorphic processes and their link with climatic conditions. In the present paper, we propose a method to produce and to update cartographic supports(Geomorphological Boxes)realized starting from a traditional geomorphological survey and mapping. The Geomorphological Boxes are geomorphological representation of single, composed or complex landforms drawn on satellite images, using the official Italian geomorphological legend(ISPRA symbols). Such cartographic representation is also addressed to the analysis(identification, evaluation and selection) of Potential Geomorphosites and Geotrails. The method has been tested in the upper portion of the Loana Valley(Western Italian Alps), located within the borders of the Sesia Val Grande Geopark, recognized by UNESCO in 2013. The area has a good potential for geotourism and for educational purposes. We identified 15 Potential Geomorphosites located along 2 Geotrails; they were ranked according to specific attributes also in relation with a Reference Geomorphosite located in the Loana hydrographic basin and inserted in official national and regional databases of geosites(ISPRA; Regione Piemonte). Finally, the ranking of Potential Geomorphosites allowed to select the most valuable ones for valorization or geoconservation purposes. In thisframework, examples of Geomorphological Boxes are proposed as supports to geo-risk education practices.展开更多
Hole repair processing is an important part of point cloud data processing in airborne 3-dimensional(3D)laser scanning technology.Due to the fragmentation and irregularity of the surface morphology,when applying the 3...Hole repair processing is an important part of point cloud data processing in airborne 3-dimensional(3D)laser scanning technology.Due to the fragmentation and irregularity of the surface morphology,when applying the 3D laser scanning technology to mountain mapping,the conventional mathematical cloud-based point cloud hole repair method is not ideal in practical applications.In order to solve this problem,we propose to repair the valley and ridge line first,and then repair the point cloud hole.The main technical steps of the method include the following points:First,the valley and ridge feature lines are extracted by the GIS slope analysis method;Then,the valley and ridge line missing from the hole are repaired by the mathematical interpolation method,and the repaired results are edited and inserted to the original point cloud;Finally,the traditional repair method is used to repair the point cloud hole whose valley line and ridge line have been repaired.Three experiments were designed and implemented in the east bank of the Xiaobaini River to test the performance of the proposed method.The results showed that compared with the direct point cloud hole repair method in Geomagic Studio software,the average repair accuracy of the proposed method,in the 16 m buffer zone of valley line and ridge line,is increased from 56.31 cm to 31.49 cm.The repair performance is significantly improved.展开更多
文摘The point cloud data obtained by airborne radar equipment has high-precision three-dimensional spatial data information, which provides a new technical means for making high-precision DEM. Although the production of lidar system hardware equipment is relatively mature, the existing data filtering and data interpolation algorithms have their own advantages and disadvantages, and it is difficult for any algorithm to meet the needs of various terrain classification. Therefore, the exploration of airborne radar technology point cloud data processing and application, and the development of more intelligent, accurate, and highly adaptable point cloud filtering algorithms are worthy of our attention and research, which are of great significance to improving the quality of DEM generation and the development and application of future airborne radar technology.
基金funded by the Fondi Potenziamento della Ricerca - Linea 2 - 2015 Project "Dynamic of active margins: from rift to collisional chains", leader Dr. Davide Zanoni
文摘Geomorphological mapping plays a key role in landscape representation: it is the starting point for many applications and for the realization of thematic maps, such as hazard and risk maps, geoheritage and geotourism maps. Traditional geomorphological maps are useful for scientific purposes but they need to be simplified for different aims as management and education. In tourism valorization, mapping of geomorphological resources(i.e., geosites, and geomorphosites), and of geomorphic evidences of past hazardous geomorphological events, is important for increasing knowledge about landscape evolution and active processes, potentially involving geomorphosites and hiking trails. Active geomorphosites, as those widespread in mountain regions, testify the high dynamicity of geomorphic processes and their link with climatic conditions. In the present paper, we propose a method to produce and to update cartographic supports(Geomorphological Boxes)realized starting from a traditional geomorphological survey and mapping. The Geomorphological Boxes are geomorphological representation of single, composed or complex landforms drawn on satellite images, using the official Italian geomorphological legend(ISPRA symbols). Such cartographic representation is also addressed to the analysis(identification, evaluation and selection) of Potential Geomorphosites and Geotrails. The method has been tested in the upper portion of the Loana Valley(Western Italian Alps), located within the borders of the Sesia Val Grande Geopark, recognized by UNESCO in 2013. The area has a good potential for geotourism and for educational purposes. We identified 15 Potential Geomorphosites located along 2 Geotrails; they were ranked according to specific attributes also in relation with a Reference Geomorphosite located in the Loana hydrographic basin and inserted in official national and regional databases of geosites(ISPRA; Regione Piemonte). Finally, the ranking of Potential Geomorphosites allowed to select the most valuable ones for valorization or geoconservation purposes. In thisframework, examples of Geomorphological Boxes are proposed as supports to geo-risk education practices.
基金National Natural Science Foundation of China(Nos.41861054,41371423,61966010)National Key R&D Program of China(No.2016YFB0502105)。
文摘Hole repair processing is an important part of point cloud data processing in airborne 3-dimensional(3D)laser scanning technology.Due to the fragmentation and irregularity of the surface morphology,when applying the 3D laser scanning technology to mountain mapping,the conventional mathematical cloud-based point cloud hole repair method is not ideal in practical applications.In order to solve this problem,we propose to repair the valley and ridge line first,and then repair the point cloud hole.The main technical steps of the method include the following points:First,the valley and ridge feature lines are extracted by the GIS slope analysis method;Then,the valley and ridge line missing from the hole are repaired by the mathematical interpolation method,and the repaired results are edited and inserted to the original point cloud;Finally,the traditional repair method is used to repair the point cloud hole whose valley line and ridge line have been repaired.Three experiments were designed and implemented in the east bank of the Xiaobaini River to test the performance of the proposed method.The results showed that compared with the direct point cloud hole repair method in Geomagic Studio software,the average repair accuracy of the proposed method,in the 16 m buffer zone of valley line and ridge line,is increased from 56.31 cm to 31.49 cm.The repair performance is significantly improved.
