Study on the Wavelet Theory and Its Applications to the Analysis of Discharge Characteristics of a Reservoir

• Main Authors: Lee, Tsung-Mu, 李宗穆
• Other Authors: Ru-yih Wang
• Format: Others
• Language: zh-TW
• Published: 1997
• Online Access: http://ndltd.ncl.edu.tw/handle/65271727164913078014

碩士 === 國立臺灣大學 === 農業工程學系 === 85 === The main purpose in this study is to build up a time-series wavelet analysismodel which reflects runoff noise and rainfall- runoff relationships , so thatit can be applied to the rainfall- runoff simulation of upland watersheds inTaiwan. For the forecasting approaches commonly applied , a suitableapproaches commonly applied , a suitable model is firstly adopted. A great deal of correctsampling data are then required to build the structure of model. However, the rainfall-runoff relationships were interfered by some uncertain factors, whichcaused major simulated errors of model.With powerful classifying data ability, wavelet analysis can separate the disturbance from runoff data. On the other hand, with a large number of model parameters, the artificial neural network model can be applied to simulate andforecast the nonlinear hydrological phenomena. The runoff process were often influenced by atmospheric condition, hydrological characteristics, physiographicfactors and human activities. Therefore, the rainfall-runoff relationships existed to be highly uncertain.By combination of wavelet analysis and ANN model can provide an effective way to solve the problems. With the separated ability of noise in wavelet analysis and solution of nonlinear equations of ANN model, thehydrological model with noise analysis, field simulation and future forecasting can be constructed.To verify the appropriateness of the approaches adopted, the upland watershed of the Te-Chi Reservoir in middle Taiwan is chosen as a project area. The results of the approaches proposed show a satisfactory simulation.Therefore, it is justifiable to reveal that this study can be further employed to estimate and forecast the peak of flood during the typhoon period in upland watersheds and play an important role on the planning of flood mitigation in Taiwan.