摘要
为了探索析取克里格插值算法中的插值参数对构建DEM精度的影响,以云南元谋干热河谷典型冲沟为例,基于野外实测点云数据,改变析取克吕格插值中的核函数、搜索点数、搜索方向和光滑因子参数构建DEM,运用交叉检验和验证数据集检验评价DEM插值精度。研究结果表明：（1）在不同的核函数中,Stable函数的插值效果最佳;（2）搜索点数为2~5个是最佳的选择;（3）在搜索方向的对比中,有方向搜索比无方向搜索误差小,且四方向比八方向的误差小;（4）当光滑因子≥0.8时,DEM插值精度的误差明显增大。通过对析取克里格插值参数的优选,在研究样区构建出0.08 m的高精度DEM,为该区域的冲沟研究提供资料。
To explore the effect of interpolation parameters on Disjunctive Kriging（DK） interpolation on DEMprecision, the authors took a typical gully of dry-hot valley in Yuanmou, Yunnan as an example, based on thefield measured point cloud data, DEM was built by changing kernel functions, search points, search directionand smoothing factors of DK interpolation, and the DEM interpolation accuracy was evaluated by crossvalidation method and the verification of test data sets. The results showed that：（1） the DEM interpolated withStable function was optimal in comparison with other functions;（2） the optimal search points was 2 to 5;（3） incomparison of different search directions, the DEM interpolated with directional search had higherinterpolation accuracy than that of the DEM interpolated with non-directional search, and interpolated withfour-directions was better than that of eight-directions;（4） the DEM interpolation error increased obviouslywhen smoothing factor ≥0.8. By the optimization of interpolation parameters in DK interpolation method, theDEM with the high precision of 0.08 m was produced, which could provide references for the studies on gully.
出处
《中国农学通报》
2016年第27期126-131,共6页
Chinese Agricultural Science Bulletin
基金
国家自然科学基金项目"基于DEM的黄土高原流域侵蚀基准体系研究"(41101348)
四川省教育厅自然科学重点项目"余震空间自相关格局研究"(2016ZA0168)
西华师范大学基本科研业务费专项资金资助项目"黄土地貌鞍部下切效应研究"(15C002)
关键词
析取克里格
点云数据
空间插值
插值参数
Disjunctive Kriging
point cloud data
spatial interpolation
interpolation parameters
