## 4 Results and Discussion
### Speed Analysis
\begin{table}
\begin{tabular}{c c c c c c c c c c c} \hline \hline \multirow{2}{*}{**S. No**} & \multirow{2}{*}{**Tunnel Lighting Colour**} & \multicolumn{4}{c}{**\(\mathbf{S}_{sij}\)**} & \multicolumn{4}{c}{**\(\mathbf{S}_{sij}\)**} & \multicolumn{2}{c}{**Mean**} & \multirow{2}{*}{**Speed**} \\  & & & & & & & & & **Difference** & **Reduction** \\  & **Colour** & \(\mu\) & \(\sigma\) & **Min.** & **Max.** & \(\mu\) & \(\sigma\) & **Min.** & **Max.** & **(km/h)** & **Ratio** \\ \hline S-1 & Blue Sky & 100.4 & 28.0 & 50.8 & 149.2 & 101.2 & 28.2 & 44.5 & 145.8 & +0.8 (\({}^{\dagger}\)) & 1.03 \\ \hline \multirow{2}{*}{S-2} & Red & 105.8 & 31.1 & 39.3 & 151.8 & 97.7 & 35.6 & 23.4 & 147.5 & \(-8.1\) (\({}^{\ddagger}\)) & 1.15 \\  & Green & 102.9 & 29.3 & 39.4 & 153.3 & 105.6 & 28.4 & 53.7 & 155.6 & +2.7 (\({}^{\ddagger}\)) & 0.97 \\ \hline \multirow{4}{*}{S-3} & Flashing & & & & & & & & & & \\  & Red on & Tunnel & & & & & & & & & \\  & Wall & & & & & & & & & & \\ \cline{1-1} \cline{2-10}  & Red & 102.7 & 35.7 & 19.0 & 149.2 & 91.8 & 39.5 & 22.2 & 139.8 & \(-10.9\) (\({}^{\ddagger}\)) & 1.22 \\ \cline{1-1} \cline{2-10}  & Green & 93.7 & 36.9 & 17.2 & 145.2 & 101.0 & 32.0 & 41.8 & 151.9 & +7.3 (\({}^{\ddagger}\)) & 0.91 \\ \hline \hline \end{tabular} Note: \(\mu=\) Mean, \(\sigma=\) Standard deviation, (\({}^{\dagger}\)) = Increase, (\({}^{\ddagger}\) = Decrease.  
\end{table} 
Table 2: Descriptive statistics results for examined three tunnel lighting scenarios. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline \multirow{2}{*}{**S. No**} & \multirow{2}{*}{**Tunnel Lighting Colour**} & \multicolumn{2}{c}{**\(\mathbf{S}_{sij}\)**} & \multicolumn{2}{c}{**\(\mathbf{S}_{sij}\)**} & \multicolumn{2}{c}{**Mean**} & \multirow{2}{*}{**Speed**} \\  & & & & & & & **Difference** & **Reduction** \\  & **Colour** & \(\mu\) & \(\sigma\) & **Min.** & **Max.** & \(\mu\) & \(\sigma\) & **Min.** & **Max.** & **(km/h)** & **Ratio** \\ \hline S-1 & Blue Sky & 100.4 & 28.0 & 50.8 & 149.2 & 101.2 & 28.2 & 44.5 & 145.8 & +0.8 (\({}^{\dagger}\)) & 1.03 \\ \hline \multirow{2}{*}{S-2} & Red & 105.8 & 31.1 & 39.3 & 151.8 & 97.7 & 35.6 & 23.4 & 147.5 & \(-8.1\) (\({}^{\ddagger}\)) & 1.15 \\  & Green & 102.9 & 29.3 & 39.4 & 153.3 & 105.6 & 28.4 & 53.7 & 155.6 & +2.7 (\({}^{\ddagger}\)) & 0.97 \\ \hline \multirow{4}{*}{S-3} & Flashing & & & & & & & & \\  & Red on & Tunnel & & & & & & & & \\  & Wall & & & & & & & & \\ \cline{1-1} \cline{2-10}  & Red & 102.7 & 35.7 & 19.0 & 149.2 & 91.8 & 39.5 & 22.2 & 139.8 & \(-10.9\) (\({}^{\ddagger}\)) & 1.22 \\ \cline{1-1} \cline{2-10}  & Green & 93.7 & 36.9 & 17.2 & 145.2 & 101.0 & 32.0 & 41.8 & 151.9 & +7.3 (\({}^{\ddagger}\)) & 0.91 \\ \hline \hline \end{tabular} Note: \(\mu=\) Mean, \(\sigma=\) Standard deviation, (\({}^{\dagger}\)) = Increase, (\({}^{\ddagger}\) = Decrease.  
\end{table} 
Table 3: Statistics for three different tunnel safety scenarios on mean spot speeds. In Table 3, the homogeneity of variances was found to be significant (\(p<0.01\)). As a result, the nonparametric Kruskal-Wallis test was used to examine whether there was a significant difference between vehicle speeds before and inside the tunnel lighting sections for each scenario. Kruskal-Wallis test results indicate that there is no significant difference in vehicle speeds before and inside the tunnel lighting sections across all scenarios (\(p>0.01\)). This suggests a relationship between entrance speed and inside speed in each scenario, confirming the intended effect of the scenarios and demonstrating the significant influence of tunnel lighting on vehicle speeds.