\documentclass{article}

\begin{document}

\begin{equation}
\label{BCC1}
\begin{array}{lll}
	\min & \theta                                                                  & {}            \\
	s.t. & \sum\limits_{j=1}^{n}{{{\lambda }_{j}}{{x}_{ij}}}\le {\theta}{{x}_{io}} & i=1,\ldots ,m \\
	{}   & \sum\limits_{j=1}^{n}{{{\lambda }_{j}}{{y}_{rj}}}\ge {{y}_{ro}}         & r=1,\ldots ,s \\
	{}   & \sum\limits_{j=1}^{n}{{{\lambda }_{j}}}=1                               & {}            \\
	{}   & {{\lambda }_{j}}\ge 0                                                   & j=1,\ldots,n  \\
\end{array}
\end{equation}	

\begin{equation}
\label{BCC2}
\begin{array}{lll}
\min & \theta                                                                  & {}            \\
s.t. & \displaystyle\sum\limits_{j=1}^{n}{{{\lambda }_{j}}{{x}_{ij}}}\le {\theta}{{x}_{io}} & i=1,\ldots ,m \\
{}   & \displaystyle\sum\limits_{j=1}^{n}{{{\lambda }_{j}}{{y}_{rj}}}\ge {{y}_{ro}}         & r=1,\ldots ,s \\
{}   & \displaystyle\sum\limits_{j=1}^{n}{{{\lambda }_{j}}}=1                               & {}            \\
{}   & {{\lambda }_{j}}\ge 0                                                   & j=1,\ldots,n  \\
\end{array}
\end{equation}	


\end{document}