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\begin{document}

	\newpage
	\tableofcontents
    \newpage

	\section{背景介绍与研究现状}
    \newpage
	\section{平衡点的线性稳定性}
	\newpage
	\section{数值模拟}\label{sec6}
	\newpage
	\section{总结与讨论}\label{sec7}

	\newpage
	\begin{thebibliography}{99}
	\addcontentsline{toc}{section}{参考文献}
	\end{thebibliography}
	
	\clearpage
	\setcounter{secnumdepth}{0}
	\section{致谢}
	%\addcontentsline{toc}{section}{致谢}
 谢谢谢谢谢
\end{document}