## 4 Simulation and Discussion
### Results
Figure 7: The convergence curves of GWO for original and “modified by DM” versions. \begin{table}
\begin{tabular}{c c c c c c c c c c c c} \hline \hline  & & **GA** & **MGA** & **PSO** & **MPSO** & **GSA** & **MGSA** & **TLBO** & **MTLBO** & **GWO** & **MGWO** \\ \hline \multirow{3}{*}{F1} & P.I. & 0.0025 & 0.0079 & 0.0011 & 0.0039 & 0.0105 & 0.0129 & 0.0055 & 0.0063 & 0.0025 & 0.0042 \\  & P.C.R. & 2.5218 & 7.9613 & 1.1309 & 3.9634 & 10.5790 & 12.9160 & 5.5465 & 6.3235 & 2.5969 & 4.2516 \\  & O.T.S. & **0.8699** & & **0.2407** & & **2.5412** & & **2.3713** & & **1.8153** \\ \hline \multirow{3}{*}{F2} & P.I. & 0.0024 & 0.0103 & 0.0019 & 0.0050 & 0.0107 & 0.0138 & 0.0056 & 0.0057 & 0.0027 & 0.0031 \\  & P.C.R. & 2.4125 & 10.3794 & 1.1945 & 5.0867 & 1.7914 & 13.8475 & 5.6229 & 5.7781 & 2.7101 & 3.1541 \\  & O.T.S. & **0.1031** & & **0.2148** & & **2.4200** & & **2.1668** & & **1.1421** \\ \hline \multirow{3}{*}{F3} & P.I. & 0.0071 & 0.1630 & 0.0035 & 0.0784 & 0.0126 & 0091 & 0.0115 & 0.0851 & 0.0075 & 0.0918 \\  & P.C.R. & 7.1174 & 163.0316 & 3.5810 & 78.4169 & 12.5987 & 91.2295 & 11.53338 & 85.1981 & 7.5661 & 91.8338 \\  & O.T.S. & **3.7623** & & **3.5364** & & **5.5923** & & **44.5162** & & **37.2164** \\ \hline \multirow{3}{*}{F4} & P.I. & 0.0023 & 0.0082 & 0.0090 & 0.00038 & 0.0102 & 0.0133 & 0.0035 & 0.0065 & 0.0026 & 0.0075 \\  & P.C.R. & 2.3254 & 8.2181 & 9.0958 & 3.8641 & 10.2537 & 13.3495 & 3.5392 & 6.5216 & 2.6966 & 7.5614 \\  & O.T.S. & **0.2793** & & **0.0721** & & **3.5859** & & **1.5757** & & **1.2614** \\ \hline \multirow{3}{*}{F5} & P.I. & 0.0031 & 0.0300 & 0.0012 & 0.0138 & 0.0106 & 0.0218 & 0.0041 & 0.0177 & 0.0035 & 0.0015 \\  & P.C.R. & 3.1018 & 30.0027 & 1.2819 & 13.8921 & 10.6810 & 21.8228 & 4.1720 & 17.7407 & 3.5823 & 15.2196 \\  & O.T.S. & **0.2677** & & **0.2105** & & **9.8639** & & **0.2629** & & **6.1547** \\ \hline \multirow{3}{*}{F6} & P.I. & 0.0024 & 0.0114 & 0.0007 & 0.0048 & 0.0101 & 0.0146 & 0.0032 & 0.0069 & 0.0027 & 0.0114 \\  & P.C.R. & 2.4156 & 11.4786 & 0.7947 & 4.8365 & 10.1832 & 14.6262 & 3.2010 & 6.9231 & 2.7229 & 11.4774 \\  & O.T.S. & **0.1558** & & **0.0870** & & **0.5940** & & **0.8843** & & **0.2376** \\ \hline \multirow{3}{*}{F7} & P.I. & 0.0047 & 0.0785 & 0.0020 & 0.0381 & 0.0107 & 0.0493 & 0.0067 & 0.0428 & 0.0049 & 0.0390 \\  & P.C.R. & 4.7185 & 78.5709 & 2.0728 & 38.1957 & 10.7416 & 49.3055 & 6.7193 & 42.8670 & 4.9646 & 39.0686 \\ \cline{1-1}  & O.T.S. & **4.3080** & & **0.1156** & & **0.9553** & & **6.5309** & & **25.3156** \\ \hline \hline \end{tabular}
\end{table} 
Table 7: Computational time analysis on unimodal objective functions (second). \begin{table}
\begin{tabular}{c c c c c c c c c c c} \hline \hline  & & **GA** & **MGA** & **PSO** & **MPSO** & **GSA** & **MGSA** & **TLBO** & **MTLBO** & **GWO** & **MGWO** \\ \hline \multirow{3}{*}{F8} & P.I. & 0.0037 & 0.0320 & 0.0015 & 0.0145 & 0.0108 & 0.0261 & 0.0049 & 0.0175 & 0.0034 & 0.0260 \\  & P.C.R. & 3.7004 & 32.0411 & 1.5194 & 14.5251 & 10.8230 & 26.1593 & 4.9084 & 17.5273 & 3.4282 & 26.0069 \\  & O.T.S. & **0** & **0** & & **0** & & **0** & & **0** \\ \hline \multirow{3}{*}{F9} & P.I. & 0.0029 & 0.0128 & 0.0011 & 0.0057 & 0.0103 & 0.0160 & 0.0041 & 0.0084 & 0.0031 & 0.0154 \\  & P.C.R. & 2.9477 & 12.8883 & 1.1813 & 5.7547 & 10.3758 & 10.6688 & 4.1855 & 8.4233 & 3.1391 & 15.3918 \\  & O.T.S. & **0** & **0.0404** & & **0.4220** & & **0.1464** & & **0.3783** \\ \hline \multirow{3}{*}{F10} & P.I. & 0.0028 & 0.0149 & 0.0014 & 0.0069 & 0.0105 & 0.0168 & 0.0036 & 0.0092 & 0.0031 & 0.0145 \\  & P.C.R. & 2.8721 & 14.9436 & 1.4455 & 6.9011 & 10.5083 & 16.8567 & 3.6440 & 9.2561 & 3.1046 & 14.5384 \\  & O.T.S. & **0.1703** & & **0.0755** & & **5.2755** & & **0.46661** & & **1.3942** \\ \hline \multirow{3}{*}{F11} & P.I. & 0.0038 & 0.0403 & 0.0015 & 0.0196 & 0.0110 & 0.0288 & 0.0049 & 0.0212 & 0.0039 & 0.0289 \\  & O.T.S. & 3.8680 & 40.3218 & 1.5616 & 19.6877 & 11.0021 & 28.8871 & 4.9292 & 21.2885 & 3.9029 & 28.93