基于可变核的月径流改进非参数解集模型研究  

Study on improved nonparametric disaggregation model of monthly runoff using variable kernel

作　　者：吴昊昊 宋松柏 WU Haohao;SONG Songbai(Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid Areas,Ministry of Education,College of Water Resources and Architectural Engineering,Northwest A&F University,Yangling,Shaanxi 712100)

机构地区：[1]西北农林科技大学水利与建筑工程学院西北农林科技大学旱区农业水土工程教育部重点实验室,陕西杨凌712100

出　　处：《水力发电学报》2021年第2期100-110,共11页Journal of Hydroelectric Engineering

基　　金：国家自然科学基金项目(51479171)。

摘　　要：径流序列模拟可为水资源系统规划和管理提供可靠依据。现行非参数解集模型模拟存在难以保持首尾自相关结构一致性,可能会产生大量负径流值的边界问题等不足。本文应用核密度估计理论,综合考虑年径流量和前期一阶月径流量与模拟月径流量的关系,采用可变核带宽方法减小边界影响,构建了月径流改进非参数解集模型,并将该模型与传统相关解集模型进行对比验证,应用于黄河流域兰州站1932—2010年天然月径流资料。结果表明:改进模型能较好地保持原径流序列的概率分布和统计参数,克服了首尾自相关结构不一致性问题,避免了大量负径流值的产生,用于月径流随机模拟是可行的。Synthetic simulation of streamflow series can afford a reliable basis for planning and management of a water resources system.Previous nonparametric disaggregation models cannot preserve a back and forth auto-correlation structure of variables and may lead to boundary problems of generating a large number of negative values of flow.In this paper,we apply the kernel density estimation theory to develop an improved nonparametric disaggregation model of monthly streamflow through a comprehensive consideration of the relationship among annual runoff,previous first-order monthly runoff,and simulated monthly streamflow,using the variable kernel bandwidth method to reduce boundary impact.This model is compared with the traditional relative disaggregation model,and used for simulating the natural monthly runoffs at Lanzhou station in the Yellow basin for the period of 1932 to 2010.The results show it can better preserve the probability distribution and statistical parameters of the original runoff series,overcome the inconsistency in the back and forth auto-correlation structure,and avoid generating negative flows,thus being applicable to stochastic simulations of monthly streamflow.

关 键 词：月径流 随机模拟 核密度估计 改进非参数解集模型 可变核 相关解集模型 

分 类 号：P333.9[天文地球—水文科学]