## 5 Results and Discussion
### Comparison of Driving Performance  
In this experimental setup, we standardized the length of the OZ at 80 m and the CZ at 170 m, maintaining uniform arrival rates across all four lane entrances. To evaluate the efficacy of the four strategies across varying traffic demands, we systematically escalated the arrival rate from 160 veh/h/lane to 800 veh/h/lane, leveraging the arrival rate values outlined in reference [11]. In our scenario of high traffic demand, where the arrival rate exceeds that of reference [11], it provides a better indication of the performance of cooperative driving strategies, particularly under extreme circumstances. When contrasting with the traffic light strategy, we categorize the FIFO, LDR, and DRP strategies collectively as cooperative driving strategies. Following a 15 min simulation period, we meticulously collected and organized data on the average travel delay and fuel consumption for all CAVs across the four strategies. These findings are detailed in Table 1 and visually depicted in Figure 8. \begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Arrival Rates (veh/h/lane)**} & \multirow{2}{*}{**Driving Strategies**} & \multirow{2}{*}{**Average Travel Delay (s)**} & \multicolumn{2}{c}{**Average Fuel**} & \multicolumn{1}{c}{**Emergency Braking**} \\  & & & **Consumption (mL)** & **(Times/Minute)** \\ \hline \multirow{4}{*}{160} & Traffic light & 17.7638 & 7.3590 & 3 \\  & FIFO & 5.5709 & 5.9439 & 0 \\  & LDR & 4.1391 & 6.3117 & 0.3 \\  & DRP & 3.3987 & 5.6261 & 0 \\ \hline \multirow{4}{*}{320} & Traffic light & 19.4790 & 7.5354 & 6.6 \\  & FIFO & 5.8475 & 6.2172 & 0 \\  & LDR & 4.365 & 6.6804 & 0.6 \\  & DRP & 3.5226 & 6.0689 & 0 \\ \hline \multirow{4}{*}{480} & Traffic light & 20.9306 & 7.7357 & 9.6 \\  & FIFO & 6.3904 & 6.9200 & 0.6 \\  & LDR & 4.732 & 7.313 & 1.8 \\  & DRP & 3.7720 & 6.4463 & 0.3 \\ \hline \multirow{4}{*}{640} & Traffic light & 23.3576 & 7.9991 & 13.8 \\  & FIFO & 17.1052 & 7.8918 & 6.3 \\ \cline{1-1}  & LDR & 14.5286 & 7.4562 & 9.5 \\ \cline{1-1}  & DRP & 13.5747 & 6.7870 & 3.3 \\ \hline \multirow{4}{*}{800} & Traffic light & 26.6526 & 8.3024 & 18.6 \\ \cline{1-1}  & FIFO & 31.8643 & 8.6395 & 11.4 \\ \cline{1-1}  & LDR & 24.9121 & 8.2642 & 12.3 \\ \cline{1-1}  & DRP & 22.7679 & 7.4544 & 7.8 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Data on the average travel delay and average fuel consumption of different driving strategies under different arrival rates. Analysis of the data presented in Table 1 reveals that cooperative driving strategies, when compared to traditional traffic light strategy, can notably diminish average travel delay by up to 82.1% under lower traffic demands, ranging from 160 veh/h/lane to 480 veh/h/lane, thus significantly augmenting traffic efficiency. The conventional traffic light strategy, rooted in fixed time cycles aimed at coordinating conflicting traffic flows, frequently impose unnecessary waiting times on CAVs, even under low-density traffic scenarios, thereby culminating in intersection delays. Furthermore, the average travel delay metrics for the DRP strategy are inferior to those of the LDR and FIFO strategies, thereby substantiating the superior efficacy of the DRP strategy in enhancing traffic efficiency. Moreover, cooperative driving strategies evince a superior energy economy performance relative to the conventional traffic light strategy, resulting in potential savings of approximately 19.84% in average fuel consumption. Nonetheless, it is imperative to note that this efficiency gain is marginally lower compared to the fuel consumption reductions observed when cooperative driving strategies are applied to fuel vehicles, amounting to approximately 46.6%. This discrepancy primarily arises from the continuous operation of fuel vehicle engines during traffic signal stops, leading to additional fuel consumption. In contrast, HEV vehicles incorporate an EV mode where the engine shuts off during traffic signal stops. Thus, despite reducing CAVs' waiting times, fuel consumption reductions are not significant.