摘要
以高精度曲面建模(HASM)方法为基础,提出了一种顾及变量梯度变化特征的DEM构建方法,将地表高程的梯度变化方向融入到HASM方法中的高斯方程构建中。实验结果表明,构建的DEM无论是从高程精度还是形态精度都优于对比方法。构建的DEM高程数值误差的绝对值最大值、平均绝对值误差、均方根误差等指标均低于对比方法,同时该方法构建的DEM高程误差的空间分布更为随机,表明该方法具有更好地稳健性,受数据质量、地形复杂程度等因素的影响较小。此外,构建的DEM生成的等高线与原始等高线偏差最小,生成的山体阴影与参照DEM生成的山体阴影相似度最好,表明构建的DEM具有更好的形态精度。本研究对复杂地形区域的DEM构建及应用分析具有一定参考价值。
As a new geographical surface modeling method,the high accuracy surface modeling(HASM)method has obvious superiority in simulation accuracy compared the classical interpolation method in many fields.HASM takes the surface theory of differential geometry as its theoretical foundation,but seldom considers the variation characteristics of the research variable itself in space,which limits the further improvement of this method.Therefore,this study improved the HASM by taking account of the gradient characteristics of variables.Taking DEM construction as an example,the gradient direction of surface elevation is integrated into the Gauss equation of the HASM method.This study selected typical experimental area,and analyzed the accuracy of optimization HASM model compared with the former HASM and other classical methods.The results show that the DEM generated by the new method is better both on elevation accuracy and morphological accuracy.As to elevation accuracy,the all the error indexes of DEMs generated by the new method are lower than those generated by other methods.Meanwhile,the error spatial distribution of the new method is more random,indicating that this method has better robustness and less influenced by factors such as data quality and complexity of the terrain.In terms of morphological accuracy,the new method proposed by this study has good morphological accuracy.This paper analyzed the morphological accuracy of DEMs generated by different methods through comparing contour lines and mountain shadows.And the results show that on the one hand,contours extracted from DEMs generated by the proposed method in this study have minimum deviation from the original contours;on the other hand,mountain shadows produced from DEMs generated by the new method in this paper present better similarity with mountain shadows produced from the reference DEMs.This study has certain reference value for DEM generation and application in areas with complex terrain.
作者
滕敏
赵明伟
TENG Min;ZHAO Ming-wei(Lianyungang Technical College,Lianyungang Jiangsu 222000,China;Chuzhou University,Chuzhou Anhui 239000,China)
出处
《现代测绘》
2019年第5期54-57,共4页
Modern Surveying and Mapping
基金
国家自然科学基金项目(41701450,41571398)
安徽省自然科学基金项目(1808085QD103)
资源与环境信息系统国家重点实验室开放基金资助(2018年度).
关键词
DEM
梯度变化
高程精度
形态精度
DEM
gradient
elevation accuracy
morphological accuracy
作者简介
第一作者:滕敏,副教授,研究方向为计算机应用技术以及软件技术。
