结合地理信息技术(Geographic Information Sciences,GIS)的计算机仿真,已经成为无线电传播信道分析的重要手段之一。仿真软件“移动无线电”(Radio Mobile)可以对指定地形下的无线电波传播过程进行数值模拟,直接识别并导入多种地形数据...结合地理信息技术(Geographic Information Sciences,GIS)的计算机仿真,已经成为无线电传播信道分析的重要手段之一。仿真软件“移动无线电”(Radio Mobile)可以对指定地形下的无线电波传播过程进行数值模拟,直接识别并导入多种地形数据,但并不包括当今精度最高且国内广为流行的免费地形数据——先进星载热发射和反射辐射仪全球数字高程模型(Advanced Spaceborne Thermal Emission and Reflection Radiometer Global Digital Elevation Model,ASTER GDEM),其精度可达30 m。因此,介绍一种如何将ASTER GDEM的数据读入Radio Mobile的处理方法。首先,利用GIS软件Global Mapper将ASTER GDEM压缩包数据转换为按照经纬度排列的DTED数据;其次,将DTED数据整理到以经度命名的文件夹内,每个文件按照纬度命名;最后,在Radio Mapper的地图属性设置中输入待仿真地域的经纬度,完成地形数据的导入。在此基础上,针对某一指定经纬度导入地形场景,利用Radio Mobile对电磁波的路径损耗做了初步的数值仿真。展开更多
This paper describes a geographic information system(GIS)-based method for observing changes in topography caused by the initiation, transport, and deposition of debris flows using highresolution light detection and r...This paper describes a geographic information system(GIS)-based method for observing changes in topography caused by the initiation, transport, and deposition of debris flows using highresolution light detection and ranging(LiDAR) digital elevation models(DEMs) obtained before and after the debris flow events. The paper also describes a method for estimating the volume of debris flows using the differences between the LiDAR DEMs. The relative and absolute positioning accuracies of the LiDAR DEMs were evaluated using a real-time precise global navigation satellite system(GNSS) positioning method. In addition, longitudinal and cross-sectional profiles of the study area were constructed to determine the topographic changes caused by the debris flows. The volume of the debris flows was estimated based on the difference between the LiDAR DEMs. The accuracies of the relative and absolute positioning of the two LiDAR DEMs were determined to be ±10 cm and ±11 cm RMSE, respectively, which demonstrates the efficiency of the method for determining topographic changes at an scale equivalent to that of field investigations. Based on the topographic changes, the volume of the debris flows in the study area was estimated to be 3747 m3, which is comparable with the volume estimated based on the data from field investigations.展开更多
基金supported by the Public Welfare & Safety Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT & Future Planning (Grant No. 2012M3A2A1050979)
文摘This paper describes a geographic information system(GIS)-based method for observing changes in topography caused by the initiation, transport, and deposition of debris flows using highresolution light detection and ranging(LiDAR) digital elevation models(DEMs) obtained before and after the debris flow events. The paper also describes a method for estimating the volume of debris flows using the differences between the LiDAR DEMs. The relative and absolute positioning accuracies of the LiDAR DEMs were evaluated using a real-time precise global navigation satellite system(GNSS) positioning method. In addition, longitudinal and cross-sectional profiles of the study area were constructed to determine the topographic changes caused by the debris flows. The volume of the debris flows was estimated based on the difference between the LiDAR DEMs. The accuracies of the relative and absolute positioning of the two LiDAR DEMs were determined to be ±10 cm and ±11 cm RMSE, respectively, which demonstrates the efficiency of the method for determining topographic changes at an scale equivalent to that of field investigations. Based on the topographic changes, the volume of the debris flows in the study area was estimated to be 3747 m3, which is comparable with the volume estimated based on the data from field investigations.
