4.2.1. Framework

Figure 1 shows the framework of the proposed multi-level classification system. The two modules of the system are the Optimized-OAO-LSSVM and baseline OAO-LSSVM module. In the system, the users can choose either the Optimized-OAO-LSSVM or baseline OAO-LSSVM module to run the data. Both modules help the user to evaluate model performance or to predict outputs. The system also enables the user to save the model after executing the training process, allowing it to be reused for other purposes.

With the baseline OAO-LSSVM module, the input data are separated into learning data and test data. After setting original input hyperparameters, the learning data help to create the model, and the test data are used to evaluate model or predict output values depending on the demand of users. The main difference between the Optimized-OAO-LSSVM and baseline module is that the input hyperparameters of the Optimized-OAO-LSSVM model are finetuned by the enhanced FA, which improves the performance of the machine learning model.

**Figure 1.** Metaheuristic-optimized multi-level classification system flowchart.
