# Urban Congestion Avoidance Methodology Based on Vehicular Traffic Thresholding
## 3 Vehicular Traffic Congestion Avoidance Methodology
#### 4.4.3 Historical/Irregular Topology--Bucharest

In the case of a high congestion on a historical/irregular road network topology in Bucharest, we reach almost the same values as for New York: a total time spent in traffic improvement of approximately 10% and an average vehicle speed improvement of approximately 55% (Table 12). As in the New York case, the historical/irregular road network topology impact on the vehicle speeds is high. As shown in Figure 11, approximately 65% of the simulated vehicles had speeds below 10 km/h and more than 32% of the simulated vehicles had speeds below 5 km/h. \begin{table}
\begin{tabular}{r r r r} \hline \hline
**Metric** & **SUMO** & **CASUMO1** & **\% Improvement** \\ \hline sav & 5.38 & 8.9 & 65.42 \\ dtotal & 640,470.58 & 714,653.69 & \(-\)11.58 \\ ttotal & 119,089.57 & 80,332.57 & 32.54 \\ tsimulation & 9.17 & 6.55 & 28.61 \\ fueltotal & 382,953.21 & 261,718.68 & 31.66 \\ CO2 total & 889,893.34 & 608,289.76 & 31.64 \\ countVpeak & 38,121 & 30,989 & 18.71 \\ \hline \hline \end{tabular}
\end{table} 
Table 10: Results and improvement of the proposed solution for 100 K+ simulated vehicles in Barcelona. Figure 9: Speed distribution in clusters for 100 K+ simulated vehicles in Barcelona with \(\delta\) = 1. \begin{table}
\begin{tabular}{r r r r} \hline \hline
**Metric** & **SUMO** & **CASUMO\({}_{\text{5}}\)** & **\% Improvement** \\ \hline s\({}_{\text{av}}\) & 4.39 & 6.03 & 37.31 \\ d\({}_{\text{total}}\) & 798,456.07 & 989,623.06 & \(-\)23.94 \\ t\({}_{\text{total}}\) & 181,704.51 & 164,018.81 & 9.73 \\ t\({}_{\text{simulation}}\) & 10.75 & 10.59 & 1.46 \\ fuel\({}_{\text{total}}\) & 591,085.62 & 553,161.89 & 6.42 \\ CO\({}_{\text{hot}}\) & 1,373,525.56 & 1,285,547.93 & 6.41 \\ countV\({}_{\text{peak}}\) & 44,273 & 49,181 & \(-\)11.09 \\ \hline \hline \end{tabular}
\end{table} 
Table 11: Results and improvement of the proposed solution for 100 K+ simulated vehicles in New York. Figure 10: Speed distribution in clusters for 100 K+ simulated vehicles in New York with \(\delta\) = 5. \begin{table}
\begin{tabular}{r r r r} \hline \hline
**Metric** & **SUMO** & **CASUMO\({}_{\text{4}}\)** & **\% Improvement** \\ \hline s\({}_{\text{av}}\) & 4.05 & 6.28 & 55.18 \\ d\({}_{\text{total}}\) & 496,049.6 & 691,303.51 & \(-\)39.36 \\ t\({}_{\text{total}}\) & 122,515.27 & 110,023.83 & 10.2 \\ t\({}_{\text{simulation}}\) & 6.66 & 6.42 & 3.63 \\ fuel\({}_{\text{total}}\) & 405,346.45 & 364,970.74 & 9.96 \\ CO\({}_{\text{hot}}\) & 941,818.95 & 848,163.21 & 9.94 \\ countV\({}_{\text{peak}}\) & 39,815 & 41,607 & \(-\)4.5 \\ \hline \hline \end{tabular}
\end{table} 
Table 12: Results and improvement of the proposed solution for 100 K+ simulated vehicles in Bucharest. #### 4.4.4 Hybrid Topology--Tokyo

Owing to the very rich road network of the hybrid topology of Tokyo, in the case of high congestion, we obtained almost the same results as for the grid topology in Barcelona, which is approximately 32% improvement for total time spent in traffic and approximately a 104% increase in speed (see Table 13). The speed increase was higher than that in Barcelona because the routes are longer due to the multiple highway alternatives used during the route computation. The chart in Figure 12 shows that more than 55% of the simulated vehicles have speeds below 10 km/h, whereas approximately 17% of the simulated vehicles have speeds below 5 km/h. This shows that our solution provides a better overall experience on Barcelona's topology (in comparison with Tokyo) in the case of high congestion. ### Barcelona Free Flow

Barcelona has the most idealistic road network topology, and we obtained very good results for 50 K+ and 100 K+ simulated vehicles. Therefore, we ran our free flow test on a selected region in Barcelona. Running SUMO with very few simulated vehicles (around 100), we found that the maximum average vehicle speed in free flow mode is almost 31.45 km/h. Considering the reports from [49], we define that, in free flow, the average vehicle's speed is at least 25 km/h.