## 5 Results and Discussion
### Evaluation of Different Algorithms Based on Computed Indexes
In fact, a smaller value for this index based on the CA during dry years showed that the intensities of failure occurrences or hydropower deficits via the CA were less than via the MBF, PSO, and GA. The RMSE for the CA based on dry years was 1.4 MW, which was 39%, 58%, and 64% less than via the MBF, PSO, and GA, respectively, when the generated hydropower was compared to hydropower plant capacity. Additionally, the MAE for the CA based on dry years was 1.2 MW, which was 42%, 62.5%, and 66% less than via the MBF, PSO, and GA, respectively. Thus, the MAE and RMSE showed that the CA could generate hydropower similar to the hydropower plant capacity. The comparison of results for the CA and other algorithms during other years also affirmed the improved performance of the CA. Another point was related to the values of different indexes during different years. For example, the TRI and VRI for wet years had the greatest values compared to other years. The VRI was 95% based on wet years for the HJA reservoir via the CA, and it was 92% and 91% for normal and dry years, respectively. All indexes during wet years had more acceptable values based on all algorithms when compared to the same algorithms during normal and dry years for all hydropower plants, which was due to more water resources for the multireservoir system during wet years. The conditions for the MBF, PSO, and GA based on dry years for all hydropower plants were more critical compared to during wet and normal years. Therefore, the values of the TRI and VRI decreased, and the RMSE and MAE increased significantly during dry years compared to during other years. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline  & & **HJD (Wet Year)** & & & \\ \hline \multirow{2}{*}{**Method**} & **Temporal** & **Volumetric** & **Vulnerability** & **RMSE** & **MAE** \\  & **Reliability Index** & **Reliability Index** & **Index** & **MW** & **MW** \\ \hline CA & 46\% & 95\% & 15\% & 0.90 & 1.0 MW \\ MBF & 42\% & 93\% & 16\% & 1.3 MW & 1.2 MW \\ PSO & 35\% & 89\% & 18\% & 1.6 MW & 2.1 MW \\ GA & 32\% & 80\% & 20\% & 1.8 MW & 2.7 MW \\ \hline \multicolumn{5}{c}{**SFY (Wet Year)**} & & \\ \hline CA & 42\% & 93\% & 22\% & 1.2 MW & 1.1 MW \\ MBF & 40\% & 85\% & 28\% & 1.6 MW & 1.4 MW \\ PSO & 29\% & 84\% & 30\% & 2.5 MW & 2.3 MW \\ GA & 26\% & 77\% & 34\% & 2.2 MW & 2.0 MW \\ \hline \multicolumn{5}{c}{**DF (Wet Year)**} & & \\ \hline CA & 47\% & 96\% & 19\% & 0.80 & 0.95 \\  & & & MW & MW \\ MBF & 43\% & 94\% & 21\% & 1.1 MW & 1.0 MW \\ PSO & 36\% & 92\% & 20\% & 1.5 MW & 1.4 MW \\ GA & 34\% & 90\% & 24\% & 1.9 MW & 1.8 MW \\ \hline \hline \end{tabular}
\end{table} 
Table 5: _Cont._For example, the TRI via the CA during dry years for the HJD hydropower plant decreased by 4% and 6% compared to normal and wet years, respectively, while it decreased during dry years at the HJD hydropower plant via the GA when compared to normal and wet years (15% and 18%, respectively). Additionally, other indexes, such as the MBF, GA, and PSO (based on dry years), had the same conditions. Thus, the PSO, GA, and MBF were more vulnerable compared to the CA when there were limited water resources during some years. Although the GA and PSO algorithms have shown a relatively good performance in previous research, the CA in this research achieved an outstanding performance better than them. This might have been due to the fact that PSO and GAs have been examined for single reservoir water systems with single objectives and have been evaluated using traditional performance indexes. In addition, the major difference in exploring the weaknesses of the GA and PSO algorithms compared to the CA is that both algorithms (GA and PSO) have been applied only for normal average climate conditions, without paying attention to the possibility of experiencing wet and dry climate conditions. Comprehensive evaluations were carried out. In fact, several multicriteria decision models could be used for the selection of the best method.