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Hybrid optimization for LSTM DO prediction

                 A                                                 B
























                C                                                  D

























                Figure 2. Scatter plots of water quality parameters versus dissolved oxygen. (A) pH versus dissolved oxygen;
                (B) Temperature versus dissolved oxygen; (C) Turbidity versus dissolved oxygen; (D) Conductivity versus
                dissolved oxygen.

                features into a multi-feature  predictive  model allows   study developed a prediction model based on an LSTM
                for the exploration of both individual effects and their   network and employed the permutation feature importance
                potential. Advanced machine learning models–such as   method to evaluate the importance of input features.
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                Random Forest, XGBoost, and LSTM–are particularly   This  method  involves  independently  shuffling  the  time
                well-suited  for this task, as they can automatically   series of each feature and observing the change in model
                capture  complex  linear  and  nonlinear  dependencies   performance (measured by MSE), thereby assessing the
                among  features.   Therefore,  by  leveraging  multi-  actual  impact  and  contribution  of  each  feature  to  the
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                feature  integration  and  the  learning  capabilities  of   prediction outcomes within the specific model.
                these algorithms, we anticipate improved accuracy in   During the evaluation, the baseline MSE of the model
                forecasting DO levels.                              on the original test set was 0.027023. Subsequently, five
                                                                    repeated random shuffling experiments were conducted
                4.1.2. Characteristic importance analysis           for each feature. The average increase in MSE and its
                To  gain  a  deeper  understanding  of  the  contribution  of   standard deviation were calculated  as indicators  of
                various water quality indicators in predicting DO, this   feature importance. The results are shown in Figure 3.



                Volume 22 Issue 5 (2025)                        73                           doi: 10.36922/AJWEP025210165
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