## 4 Methodology
### Mutation Strategies
As speech emotion recognition becomes increasingly vital in various applications, including human-computer interaction, virtual assistants, and the ability to quickly and effectively process and analyze emotions. Our work provides a foundation for enhancing the applicability of such systems. Emotion recognition is a multifaceted task. To further enhance the robustness and accuracy of our proposed algorithm, it is important to consider integrating other modalities, such as facial expression analysis. This multimodal approach can provide a more comprehensive understanding of users' emotional state. Additionally, our algorithm can be applied to different languages, which is an important avenue for exploration. Conceptualization, L.Y. and P.H. ; Formal analysis, L.Y. and S.-C.C. ; Methodology, L.Y., S.-C.C. and J.-S.P. ; Software, L.Y. and P.H. ; Writing--Original draft preparation, L.Y. ; Writing--Review and editing, P.H., S.-C.C. and J.-S.P. All authors have read and agreed to the published version of the manuscript. This work is supported by the Henan Provincial Philosophy and Social Science Planning Project (2022 BJJ076), and the Henan Province Key Research and Development and Promotion Special Project (Soft Science Research) (222400410105). Not applicable. Data is contained within the article. The authors declare no conflict of interest. ## References

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\begin{tabular}{c c c c c c c c c} \hline \hline \multirow{2}{*}{**Dataset**} & \multicolumn{3}{c}{**DE**} & \multicolumn{3}{c}{**BBO\_PSO**} & \multicolumn{3}{c}{**SCA**} & \multicolumn{3}{c}{**MDE**} \\ \cline{2-9}  & **Length** & **Time** & **Length** & **Time** & **Length** & **Time** & **Length** & **Time** \\ \hline eNTERFACE05 & 69.4 & 9999.6274 & 68 & 10,775.6739 & **28.8** & **7119.838** & 68.6 & 11,094.3004 \\ RAVDESS & 66.6 & 34,730.7615 & 69.6 & 32,983.0796 & **26.4** & **22,223.1923** & 68.6 & 36,696.1692 \\ SAVEE & 66.2 & 11,116.0668 & 66.6 & 12,783.4402 & **20.4** & **9221.0034** & 68.8 & 11,135.3497 \\ TESS & 71 & 34,910.0227 & 69.8 & 39,412.2563 & **38.6** & **29,448.3799** & 65.8 & 41,026.9059 \\ \hline \hline \end{tabular}
\end{table} 
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