【摘 要】
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Reliable modeling of river sediments transport is important as it is a defining factor of the economic viability of dams,the durability of hydroelectric-equipment,river susceptibility to pollution,suitability for navigation,and potential for aesthetics an
【机 构】
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State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering,Hohai University,Nanjing
论文部分内容阅读
Reliable modeling of river sediments transport is important as it is a defining factor of the economic viability of dams,the durability of hydroelectric-equipment,river susceptibility to pollution,suitability for navigation,and potential for aesthetics and fish habitat.The capability of a new machine learning model,fuzzy c-means based neuro-fuzzy system calibrated using the hybrid particle swarm optimization-gravitational search algorithm (ANFIS-FCM-PSOGSA) in improving the estimation accuracy of river suspended sediment loads (SSLs) is investigated in the current study.The outcomes of the proposed method were compared with those obtained using the fuzzy c-means based neuro-fuzzy system calibrated using particle swarm optimization (ANFIS-FCM-PSO),ANFIS-FCM,and sediment rat-ing curve (SRC) models.Various input combinations involving lagged river flow (Q) and suspended sediment (S) values were used for model development.The effect of Q and S on the model\'s accuracy also was assessed by including the difference between lagged Q and S values as inputs.The model perfor-mance was assessed using the root mean square error (RMSE),mean absolute error (MAE),Nash-Sutcliffe Efficiency (NSE),and coefficient of determination (R2) and several graphical comparison methods.The results showed that the proposed model enhanced the prediction performance of the ANFIS-FCM-PSO (or ANFIS-FCM) models by 8.14% (1.72%),14.7% (5.71%),12.5% (2.27%),and 25.6% (1.86%),in terms of the RMSE,MAE,NSE and R2,respectively.The current study established the potential of the proposed ANFIS-FCM-PSOGSA model for simulation of the cumulative sediment load.The modeling results revealed the potential effects of the river flow lags on the sediment transport quantification.
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