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\begin{equation}\label{(2.3)}
\begin{array}{rl}
\min &  \displaystyle\sum_{r=1}^{s} s_r\\
 s.t & \displaystyle\sum_{\substack{ j=1\\ j\neq k }}^{n}\lambda_{j} y_{rj}\geqslant y_{rk}\qquad r=1,...,s\\
& \displaystyle\sum_ {\substack{j=1\\ j\neq k}}^n \lambda_j =1\\
& \lambda_j \geqslant 0, \quad  j\neq k  \\
& s_r \geqslant 0
\end{array} 
\end{equation}


begin{quotation*}
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\begin{array}{rl}
\min  &(s_1,...s_s)\\
s.t     &\left(x_p ,  (1-(s_1,...s_s) )y_p\right)\in T_v
\end{array}
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\end{quotation*}\\


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