A self-adaptive evolutionary weighted extreme learning machine for binary imbalance learning

Implementation of Chaotic Reverse Slime Mould Algorithm Based on the Dandelion Optimizer

This paper presents a hybrid algorithm based on the slime mould algorithm (SMA) and the mixed dandelion optimizer. The hybrid algorithm improves the convergence speed and prevents the algorithm from falling into the local optimal. (1) The Bernoulli chaotic mapping is added in the initialization phase to enrich the population diversity. (2) The Brownian motion and Lévy flight strategy are added to further enhance the global search ability and local exploitation performance of the slime mould. (3) The specular reflection learning is added in the late iteration to improve the population search ability and avoid falling into local optimality. The experimental results show that the convergence speed and precision of the improved algorithm are improved in the standard test functions. At last, this paper optimizes the parameters of the Extreme Learning Machine (ELM) model with the improved method and applies it to the power load forecasting problem. The effectiveness of the improved method in solving practical engineering problems is further verified.

Fusion Algorithm for Imbalanced EEG Data Processing in Seizure Detection

PURPOSE

Seizure detection algorithms (SDAs) based on electroencephalography (EEG) have been described in previous studies, but the imbalanced data distribution of ictal and interictal states continue to pose a technical challenge. This study proposes a novel algorithm to address the imbalanced classification problem and improve seizure detection performance.

METHOD

The proposed algorithm is designed based on hybrid sampling and a cost-sensitive (CS) classifier. Hybrid sampling resamples the imbalanced EEG data at data-level, and the CS classifier, which is used as an algorithm-level tool, reduces the overall misclassification cost of seizure detection. The synthetic minority oversampling technique and undersampling TomekLink technique are combined to reduce the imbalanced ratio between ictal and interictal states while retaining the generalization ability. Finally, CS support vector machine classifies the resampled EEG feature vectors, assigning different cost sensitive parameters to moderate the poor performance resulting from the imbalanced distribution problem.

RESULT

The proposed algorithm improved the average sensitivity and AUC by 46.67% and 0.0482, respectively, compared with the original results without using the imbalanced EEG data processing (IEDP) technique. Experimental results showed that an average sensitivity and AUC of 86.34% and 0.9837, respectively, could be obtained across all cases. Finally, a performance evaluation showed that the proposed algorithm outperformed published methods in terms seizure detection.

CONCLUSION

A fusion algorithm combining data- and algorithm-level methods can achieve high sensitivity and AUC compared with existing IEDP methods. Thus, SDA performance can be improved, enabling their clinical use with EEG-based SMSs.