加权距离判别法在泥石流危险度评价中的应用

Application of Weighted Distance Discriminant Analysis in Debris Flow Risk Assessment

将加权距离判别法引用到泥石流危险度分类中,建立了泥石流危险度分类模型。该模型选用了流域面积、主沟长度、流域最大相对高差、流域切割密度、主沟床弯曲系数、人口密度、泥沙补给长度比、植被覆盖率、一次泥石流(可能)最大冲出量和泥石流发生频率10项指标为建模参数,运用熵值法对这10个指标进行赋权,用已经分类的泥石流沟作为训练样本进行学习,建立了相应的判别准则。将待判泥石流沟样本代入判别准则进行判别分类,分类结果与传统分类结果100%吻合,验证了该模型的分类性能良好。该方法可以在实际工程中进行推广。

Based on the principle of weighted distance discriminant analysis,a classification model of debris flow risk assessment is built.Considering from ten key factors including watershed area,valley length,watershed relative height difference,valley incision density,bending coefficient of major ditch bed,population density,the length ratio of sediment supplement,forest cover rate,the most volume of once flow and frequency.Weights are obtained for ten factors based on entropy method.A model of distance discriminant analysis is established though training debris flow samples which come from the field investigation.The result preferably coincides with the normalization method,it was shown that the model of distance discriminant analysis performed excellently with high prediction accuracy and could be used in practical engineering.