Skip to Main Content

The BPNN and MIKE 21 models were compared based on R2, Ens, and RMSE values (see Table 4). The water levels at Hukou could not be used for the evaluation of model performance, because these were assigned as the lower boundary condition for the MIKE 21 model, as per Li et al. (2014). It is common for physical models to be judged also on the match between calibrated and field-measured model parameters (Doherty & Johnston 2003), but here, there is a lack of knowledge pertaining to the ‘true’ values of model parameters, and rather, we ensure that MIKE 21 model parameters fall within acceptable ranges. The model-measurement RMSE values (Table 4) indicate that the MIKE 21 model is superior to the BPNN approach in reproducing lake water levels at Xingzi, Duchang, and Tangyin gauging stations, whereas the reverse is true for Kangshan gauging station. In general terms, the MIKE 21 and BPNN models produce largely similar model-measurement performance statistics across all four gauging stations and for the period of simulation.

Table 4

Performance evaluation of BPNN and MIKE 21 models in training and testing phases (2000–2008) at five gauging stations

Location
MethodPerformanceHukouXingziDuchangTangyinKangshan
BPNN Training R2 0.98 0.97 0.96 0.95 0.94 
Training Ens 0.98 0.97 0.96 0.95 0.94 
Training RMSE (m) 0.53 0.55 0.53 0.48 0.42 
Testing R2 0.97 0.97 0.95 0.93 0.88 
Testing Ens 0.97 0.95 0.91 0.90 0.90 
Testing RMSE (m) 0.59 0.75 0.98 0.63 0.54 
MIKE 21 Training R2 – 0.99 0.98 0.97 0.96 
Training Ens – 0.97 0.98 0.94 0.88 
Training RMSE (m) – 0.45 0.36 0.48 0.52 
Testing R2 – 0.98 0.98 0.97 0.94 
Testing Ens – 0.95 0.93 0.97 0.80 
Testing RMSE (m) – 0.62 0.64 0.34 0.58 
Location
MethodPerformanceHukouXingziDuchangTangyinKangshan
BPNN Training R2 0.98 0.97 0.96 0.95 0.94 
Training Ens 0.98 0.97 0.96 0.95 0.94 
Training RMSE (m) 0.53 0.55 0.53 0.48 0.42 
Testing R2 0.97 0.97 0.95 0.93 0.88 
Testing Ens 0.97 0.95 0.91 0.90 0.90 
Testing RMSE (m) 0.59 0.75 0.98 0.63 0.54 
MIKE 21 Training R2 – 0.99 0.98 0.97 0.96 
Training Ens – 0.97 0.98 0.94 0.88 
Training RMSE (m) – 0.45 0.36 0.48 0.52 
Testing R2 – 0.98 0.98 0.97 0.94 
Testing Ens – 0.95 0.93 0.97 0.80 
Testing RMSE (m) – 0.62 0.64 0.34 0.58 

Close Modal

or Create an Account

Close Modal
Close Modal