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%% http://tex.stackexchange.com/questions/294092/special-arrangements-of-subfigures
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\documentclass{jarticle}
\usepackage{array}
\usepackage[demo]{graphicx}

\begin{document}

\begin{figure}[htbp]
\centering\begin{tabular}{cc*{3}{>{\centering\arraybackslash}p{0.28\textwidth}}}
&   $N=150$ &   $N=150$ &   $N=250$ \\
\rotatebox{90}{\qquad$t=0$}
&   \includegraphics[width=3cm]{tiger.eps}
&   \includegraphics[width=3cm]{tiger.eps}
&   \includegraphics[width=3cm]{tiger.eps}   \\
\rotatebox{90}{\qquad$t=100$}
&   \includegraphics[width=3cm]{tiger.eps}
&   \includegraphics[width=3cm]{tiger.eps}
&   \includegraphics[width=3cm]{tiger.eps}   \\
\rotatebox{90}{\qquad$t=200$}
&   \includegraphics[width=3cm]{tiger.eps}
&   \includegraphics[width=3cm]{tiger.eps}
&   \includegraphics[width=3cm]{tiger.eps}   \\
\end{tabular}
\caption{キャプション}
\end{figure}
\end{document}
