نوع مقاله : مقاله پژوهشی
نویسندگان
1 دانشجوی دکترای عمران/ آب و هیدرولیک، دانشگاه فردوسی مشهد، مشهد، ایران
2 استادیار/ گروه عمران دانشکده مهندسی، دانشگاه فردوسی مشهد، مشهد، ایران
3 دانشیار /گروه عمران دانشکده مهندسی، دانشگاه فردوسی مشهد، مشهد، ایران
4 استادیار /گروه ریاضی، دانشگاه تربیت معلم سبزوار، سبزوار، ایران
چکیده
کلیدواژهها
عنوان مقاله [English]
نویسندگان [English]
This paper applies the discrete wavelet transform to decompose the instantaneous unit hydrograph (IUH) into low and high frequency bands. The fast Fourier transform exploits to extract IUH from observed rainfall – runoff data. It is estimated the oscillations of IUH by wavelet coefficients and coefficients that are close to zero are set to zero. The obtained result is a hydrograph with the information of low frequency that approximates the real IUH. Calibration criteria between observed and calculated hydrographs are used to select the best filter length in wavelet. In this research, it is demonstrated that wavelets introduced by Daubechies (1992) with filter length 6 is the best alternative in this study. The results have shown that the methodology is acceptable for the system identification of rainfall – runoff for small catchments
کلیدواژهها [English]