# Priority of Emergency Vehicle Dynamic Right-Of-Way Control Method in Networked Environment
## 3 Experimental Verification
### Simulation Experiments and Data Analysis
#### 3.2.2 Analysis of Experimental Results
Since there is no lane change in the PSR method, the PDR method is a semi-free lane change (CV entry into the buffer requires a forced lane change), and the ER method is a completely free lane change, which also displays that the lane change has an adverse effect on the system, thus reducing the operating efficiency of the system. The results in Figure 12b indicate the effect of the speed difference between EVs and CVs compared to the actual EV operating speed, where the length of the two physical functional areas is depicted in Figure 12a, and the flow input was constant at 1300 pcu/h. The difference between the desired and actual EV speed under the ER method was the largest, thus indicating that EVs have the greatest resistance to travel under the ER condition and the greatest degree of impact on the EV's operating efficiency. Then, without dedicated lanes (PDR method compared to ER method), the PDR method could significantly reduce EV driving resistance, and the operating effect was almost the same as the PSR when the speed difference was not large. It is not difficult to understand that the EV's speed was reduced. Combining the above two sets of experiments, it is evident that, under the PDR method, when the EV's speed is low, the length of the corresponding buffer zone should be reduced, and the corresponding saturation is high. When the EV's speed is high, the corresponding buffer length should be increased, the saturation is low, and the buffer length and speed present a proportional trend. \begin{table}
\begin{tabular}{c c c c} \hline \hline  & \multicolumn{3}{c}{**(a)**} \\ \hline \multirow{2}{*}{**Input Saturation**} & \multicolumn{3}{c}{**Running Time of CV (s)**} \\ \cline{2-4}  & ER & PSR & PDR \\ \hline
0.25 & 84.9 & 84.8 & 85.22 \\
0.29 & 85 & 84.9 & 85.36 \\
0.33 & 85.1 & 85 & 85.55 \\
0.38 & 85.3 & 85.15 & 8  
By combining the advantages and disadvantages of the three methods mentioned above, it becomes clear that the PSR and ER methods are very extreme. The PSR method reflects a significant advantage for EVs by gaining absolute right-of-way, but this methodology has the greatest impact on other vehicles. In contrast, the ER method guarantees an equal right-of-way for all vehicles and fairness. However, EVs operate the least efficiently under this organization method. The proposed PDR method considers the operational efficiency of both EVs and CVs, and the PDR method has the best overall performance. The above experiments reveal the interaction mechanism between EVs and CVs from different perspectives. However, the space resources on the road are limited. If the priority of EVs increases, the operating efficiency of the CVs must be reduced, thus showing a trend of trade-offs. In practice, the operating efficiency of EVs should be much higher than that of CVs. Noticeably, the operating efficiency of CVs is directly related to the operating efficiency of EVs. Figure 10a,b demonstrate the mechanism impacting the CVs' lane change on the operational efficiency of roadway traffic. Therefore, in high-urgency emergency rescue missions, the impact of CVs on EVs can be reduced by adjusting CV lane change  
Figure 12: Impact of CVs and EVs operations on road congestion: (**a**) CVs and (**b**) EVs. rates so that EVs can achieve a higher operational efficiency. In low-urgency emergency missions, the impact on CVs can be minimized while maintaining the efficiency of the EV's' operation. Figure 13 illustrates the net gain of the system operation for the PDR method with different weights of CVs. The value of \(w\) reduces the frequency of lane change from the inner CVs to the outer lane to varying degrees. \(w\) = 0 represents the curve without attenuated CV influence, while \(w\) = 1 denotes the curve under prohibited CV lane changes to the outer lane. In Figure 13a, the length of the non-intrusive interval was \(L_{1}=15\) m, the length of the buffer zone was \(L_{2}=90\) m, and the flow input was changed from 600 pcu/h to 2000 pcu/h.