## 4 Simulation
### The Performance of the Proposed Scheme  
In the simulation, we compare the proposed scheme with the resource re-allocation scheme presented in Reference [23] (referred to as Scheme 1 for simplification). Figures 6-9 show the proportion of service-guaranteed users for different values of \(K\), \(V\), \(N\), and \(d^{V}\), respectively. From Figures 6-9, it is observed that the proposed scheme results in a higher proportion of service-guaranteed users than Scheme 1. This is because the proposed scheme selects some of the users to receive guaranteed service by dropping others when the scale of demand exceeds the service capability of the resources, whereas Scheme 1 provides insufficient services to all users. The proportion of service-guaranteed users is higher at \(\lambda=1/1000\) than that achieved using \(\lambda=1/500\) because the network is denser at a higher value of \(\lambda\). In addition, Figure 7 shows that the proportion of service-guaranteed users increases with the increase in \(V\). This is because the control parameter is the coefficient of the number of service-guaranteed users in the drift-plus-penalty function. A higher value of \(V\) indicates a greater focus on the number of service-guaranteed users in the optimization problem, as shown in Equation (30). Figures 8 and 9 show that the proportion of service-guaranteed users decreases with the increase of \(N\) and \(d^{V}\). This is because the network becomes denser with the increase in \(N\) and the desired signal declines with the increase in \(d^{V}\). Figure 5: Average non-outage probability for different distances between the corresponding transmitter and receiver in a platoon \(d^{V}(\lambda=1/1000,V=10,N=5)\). Figure 6: Proportion of service-guaranteed users for different numbers of channels \(K(d^{V}=10,V=10,N=5)\). Figure 7: Proportion of service-guaranteed users for different control parameter values \(V(d^{V}=10,K=3,N=5)\). Figures 10 and 11 show the rate and the average queue size of re-allocation for different numbers of channels \(K\), respectively. It is observed that both the rate and the average queue size of re-allocation increase with the increase in \(K\). There are two reasons for this: first, there are more opportunities for the MUs to obtain a channel with better conditions as \(K\) increases; second, there are more opportunities for the VUs to be guaranteed due to the re-allocation of the channels as \(K\) increases. Figure 8: Proportion of service-guaranteed users for different numbers of vehicles in a platoon \(N(d^{V}=10,K=3,V=10)\). Figure 9: Proportion of service-guaranteed users for different distances between the corresponding transmitter and receiver in a platoon \(d^{V}(N=5,K=3,V=10)\). Figures 12 and 13 show the rate and the average queue size of re-allocation for different values of \(d^{V}\), respectively. It is observed that both the rate and the average queue size of re-allocation decrease with the increase in \(d^{V}\). As shown in Figures 4 and 5, as \(d^{V}\) increases, the availability probability remains almost constant and the non-outage probability decreases. Therefore, the re-allocation decreases with the decrease in the number of channels that satisfies \(\xi_{nk}(t)=1\). Figure 11: Average queue size of the re-allocation for different numbers of channels \(K(d^{V}=10,V=10,N=5)\). Figure 10: Rate of re-allocation for different numbers of channels \(K(d^{V}=10,V=10,N=5)\). Figure 14 shows the rate of re-allocation for different control parameter values \(V\). With the increase in \(V\), it can be seen that the rate of re-allocation increases. This is because re-allocation is used to increase the number of service-guaranteed users, which can be seen from Figure 7. Figures 7 and 14 show that there is a trade-off between the number of service-guaranteed users and the re-allocation performance; moreover, the results depend on the value of \(V\). Figure 12: Rate of re-allocation for different distances between the corresponding transmitter and receiver in a platoon \(d^{V}\left(K=3,V=10,N=5\right)\).