\title{******}
\author{******\thanks{e-mail:******},******\thanks{e-mail:******}\\your own institute}
\begin{document}
\begin{abstract}
******
\begin{CRcatlist}
\CRcat{I.3.7}{Computer Graphics}{Three-Dimensional Graphics and Realism}{Raytracing};
\end{CRcatlist}
\textbf{Keywords:} ******
%%or we can use this method as follows:
%%\keywords{******}
end{abstract}
******
\end{document}