Streamflow forecasting is one of the most important components of water resources management. Accurate long-term forecasts are essential for planning water supply and storage, while short-term predictions are crucial for anticipating extreme flows and supporting flood warning systems. Data-driven models, as relatively simple yet powerful approaches, are widely used for streamflow prediction. The K-Nearest Neighbors (KNN) method is an effective non-parametric learning approach that has been applied to solve various problems. In this study, a novel neighbor selection method called Dynamic K-Nearest Neighbors (DKNN) is introduced. Using an SVM model, optimal distance thresholds are determined, and neighbors located within this optimal range are selected for each prediction case. The performance of the proposed method was evaluated using two years of daily inflow data from the Gheshlagh Dam in western Iran. The results indicate that the proposed method improves prediction accuracy by reducing the overall error (RMSE) by 6%, with the improvement reaching 7.8% in predicting extreme events.
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Ebrahimi, E., & Shourian, M. (2025). Dynamic K-Nearest Neighbors (DKNN) Approach Optimized by PSO for Daily River Inflow Prediction. Journal of Advanced Informatics in Water, Soil, and Structure, 1(2), 255-267. https://doi.org/10.22048/wss.2026.575197.1021
MLA
Ebrahimi, E., & Shourian, M. "Dynamic K-Nearest Neighbors (DKNN) Approach Optimized by PSO for Daily River Inflow Prediction", Journal of Advanced Informatics in Water, Soil, and Structure, 1, 2, 2025, 255-267. doi: 10.22048/wss.2026.575197.1021
HARVARD
Ebrahimi E., Shourian M. (2025). 'Dynamic K-Nearest Neighbors (DKNN) Approach Optimized by PSO for Daily River Inflow Prediction', Journal of Advanced Informatics in Water, Soil, and Structure, 1(2), pp. 255-267. doi: 10.22048/wss.2026.575197.1021
CHICAGO
E. Ebrahimi & M. Shourian, "Dynamic K-Nearest Neighbors (DKNN) Approach Optimized by PSO for Daily River Inflow Prediction," Journal of Advanced Informatics in Water, Soil, and Structure, 1 2 (2025): 255-267, doi: 10.22048/wss.2026.575197.1021
VANCOUVER
Ebrahimi E., Shourian M. Dynamic K-Nearest Neighbors (DKNN) Approach Optimized by PSO for Daily River Inflow Prediction. AIWSS. 2025;1(2):255-267. doi: 10.22048/wss.2026.575197.1021
