水文
水文
수문
HYDROLOGY
2009年
6期
9-13,57
,共6页
董晓华%刘冀%徐刚%杜发兴%玄英姬%冯升华
董曉華%劉冀%徐剛%杜髮興%玄英姬%馮升華
동효화%류기%서강%두발흥%현영희%풍승화
目标函数%马斯京根法%流量演算精度
目標函數%馬斯京根法%流量縯算精度
목표함수%마사경근법%류량연산정도
objective function%Muskingum method%channel routing accuracy
在用马斯京根法进行河道流量演算时,由于传统的试算法在精度和客观性上的欠缺,目前广泛使用最小二乘法来进行优化计算.在应用最小二乘法时,发现选择不同的目标函数会对最终的流量计算结果的精度产生影响.因此,本文应用了两种目标函数:河槽蓄量误差最小和出流量误差最小,推导了它们在最小二乘意义上的流量演进参数解析式,进而研究了对流量计算精度的影响.对3场洪水过程的模拟结果表明,以出流量误差最小为目标函数所获得的流量计算精度更高:与河槽蓄量误差最小相比,相对平均绝对误差分别降低了4%,25%和25%,说明使用出流量误差最小作为优化的目标函数更为有效.
在用馬斯京根法進行河道流量縯算時,由于傳統的試算法在精度和客觀性上的欠缺,目前廣汎使用最小二乘法來進行優化計算.在應用最小二乘法時,髮現選擇不同的目標函數會對最終的流量計算結果的精度產生影響.因此,本文應用瞭兩種目標函數:河槽蓄量誤差最小和齣流量誤差最小,推導瞭它們在最小二乘意義上的流量縯進參數解析式,進而研究瞭對流量計算精度的影響.對3場洪水過程的模擬結果錶明,以齣流量誤差最小為目標函數所穫得的流量計算精度更高:與河槽蓄量誤差最小相比,相對平均絕對誤差分彆降低瞭4%,25%和25%,說明使用齣流量誤差最小作為優化的目標函數更為有效.
재용마사경근법진행하도류량연산시,유우전통적시산법재정도화객관성상적흠결,목전엄범사용최소이승법래진행우화계산.재응용최소이승법시,발현선택불동적목표함수회대최종적류량계산결과적정도산생영향.인차,본문응용료량충목표함수:하조축량오차최소화출류량오차최소,추도료타문재최소이승의의상적류량연진삼수해석식,진이연구료대류량계산정도적영향.대3장홍수과정적모의결과표명,이출류량오차최소위목표함수소획득적류량계산정도경고:여하조축량오차최소상비,상대평균절대오차분별강저료4%,25%화25%,설명사용출류량오차최소작위우화적목표함수경위유효.
The Least Squares(LS)method is the most commonly used optimization method in applying the Muskingum method for flow routing in river channels, to remedy the negative influence of the traditional trial-and-error method,for being lack of accuracy and objectivity.When the LS method was used as the optimization method,it was discovered that application of different objective functions would influence the accuracy of the outflow muting results.Therefore,in order to investigate this affection,this study applied two objective functions:minimal storage calculation error and minimal outflow calculation error,in optimizing the river channel flow muting.The analytical solutions of the estimated parameters were deduced based on two objective functions,and their influence on the routing accuracies were investigated. The simulation results of three flood events show that,the routing accuracy by using the minimal outflow error is less than that using the minimal storage calculation error as the objective function:respectively being decreased at a rate of 4%,25% and 25% for the Relative Mean Absolute Error(RMAE)being used as the accuracy index,indicating that the minimal outflow calculation error is a more effective objective function in this occasion.