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\hyphenation{op-tical net-works semi-conduc-tor}
\begin{document}
\title{Hi}
\author{}
\maketitle
\IEEEpeerreviewmaketitle


\section{Introduction}

\begin{table*}[tp]
\centering
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\begin{minipage}{0.5\textwidth}
\centering
\caption{x}
\label{tab:2}
\begin{tabular}{c >{$}c<{$}@{\hskip1.5em}S[table-format=1.4]S[table-format=2.1]}
\toprule
\multicolumn{2}{c}{\thead{VSI Controller\\Parameters}} & {\thead{Minimum\\Value}} & {\thead{Maximum\\Value}} \\
\otoprule
\multirowcell{4}{Outer Control \\ Loops} & k_{p_1} & 0.002 & 5 \\
                               & T_{i_1} & 0.0001 & 0.5 \\
                               & k_{p_2} & 0.01 & 3 \\
                               & T_{i_2} & 0.0001 & 0.5 \\
\midrule
\multirowcell{4}{Inner Control \\ Loop} & k_{p_3} & 0.1 &  15  \verb+  + \\
                               & T_{i_3} & 0.001 & 0.5 \\
                               & k_{p_4} & 0.1 &  10  \verb+  + \\
                               & T_{i_4} & 0.001 & 0.5 \\
\bottomrule
\end{tabular}
\end{minipage}%
\begin{minipage}{0.5\textwidth}
\centering
\caption{Results }
\label{tab:3}
\begin{tabular}{c S[table-format=1.2] S[table-format=1.4]S[table-format=2.1]}
\toprule
\thead{Controller}   &  {\thead{Initial}}  &  {\thead{1\textsuperscript{st} $ PI$}} &    {\thead{2\textsuperscript{nd} $PI2$} }\\
\thead{Parameters}        &    {\thead{fd}}    &        {\thead{Tuning}}          &           {\thead{Tuning}}        \\  
    \otoprule

$k_{p_1}$         &2            &   3.5467                  &   3.5467\\

$ T_{i_1}$         &0.02         &   0.0014                &   0.0014\\

    $k_{p_2}$         &1            &   1.9389                &   1.9389\\

    $T_{i_2}$         &0.05            &   0.1846                &   0.1846\\

    $k_{p_3}$         &10            &   10                &   9.0243\\

    $T_{i_3}$         &0.05            &   0.05                &   0.2975\\

    $k_{p_4} $        &3.4            &   3.4                &   3.8011\\

    $T_{i_4} $        &0.05            &   0.05                &   0.0650\\

\bottomrule
\end{tabular}
\end{minipage}
\bigskip

\caption{How To Tune it. $P_{max}$ is First Peak; $PP_{ss}$ is Steady-State; etc.}
\label{tab:4}
\centering
\begin{tabular}{c c *{2}{S[table-format=1.4]} S[table-format=-2.2] *{3}{S[table-format=1.4]} S[table-format=-1.2] S[table-format=1.4]}
\toprule

 & & \multicolumn{4}{c}{Some text} & \multicolumn{4}{c}{Some text} \\ \cmidrule(lr){3-6} \cmidrule(lr){7-10}
 \thead{Case} &  {\thead{Controller}} & {\thead{$P_{\mathrm{max}}$}}  &  {\thead{$P_{\mathrm{ss}}$}}  &  {\thead{$M_p$\%}}  & {\thead{$t_s$}}  & {\thead{$V_{\mathit{DC}}^{\mathrm{max}}$}}  &  {\thead{${V_{\mathit{DC}}^{\mathrm{ss}}}$}}  &  {\thead{$M_p$\%}}  & {\thead{$t_s$}} \\

\otoprule
$\text{case}=1$ \\ % I would rather say just Case 1, but that's up to you of course
       & \thead{Manual}    &   0.7880     &   0.4778    &    64.92   &    2.988   &   1.0591   &     1.0001    &    5.9    &    3.6128     \\
       & \thead{\num{1}\textsuperscript{st} PI1} &   0.6487     &   0.4779    &    35.74   &    0.368   &   1.0132   &     1.0000      &    1.32   &    0.3664s    \\
       & \thead{\num{2}\textsuperscript{nd} PI2} &   0.6489     &   0.4782    &    35.7    &    0.368   &   1.0132   &     1.0000      &    1.32   &      0.3664     \\                                 
%\midrule % there were no midrule in the picture 
$\text{case}=2$ \\
       & \thead{Manual}    &   0.0735     &   0.2295    &   -67.97   &    0.3248  &   0.9685   &     1.0000   &    -3.15   &    1.9600     \\
       & \thead{\num{1}\textsuperscript{st} PI1} &   0.0961     &   0.2295    &   -58.13     &    0.1200  &   0.9919   &       1.0000     &    -0.81   &      0.1984     \\
       & \thead{\num{2}\textsuperscript{nd} PI2} &   0.0932     &   0.2295      &   -59.39   &    0.1184  &   0.9917     &     1.0000     &    -0.83   &      0.1984     \\
%\midrule
$\text{case}=2$ \\
       & \thead{Manual}    &   1.0442     &  0.7331     &    42.44   &    3.7984  &   1.0617   &   1.0000     &     6.18    &   8.3168     \\
       & \thead{\num{1}\textsuperscript{st} PI1} &   0.9721     &  0.7319       &    32.82   &    0.5248  &   1.0165     &   1.0000     &     1.65    &   0.4144     \\
       & \thead{\num{2}\textsuperscript{nd} PI2} &   0.9725     &  0.7313       &    32.98   &    0.5200  &   1.0165   &     1.0000     &       1.65    &     0.4112     \\                                         

\bottomrule
\end{tabular}
\end{table*}

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