## 3 Simulation Experimental Design
### Specific Simulation Schemes  
SUMO is a freely available open-source microscopic traffic simulation software. It includes a car-following model called CACC, which enables the simulation of vehicle traffic flow. SUMO's simulation scenarios also encompass public transportation, making it suitable for conducting simulation experiments involving both CAVs and buses, aligning with the requirements of this study. Therefore, SUMO software is utilized to simulate traffic flow under the CAVs environment. The dual-lane with bus stop of open boundary conditions and calibrated parameters was simulated based on survey data. The simulation was conducted in SUMO, and each of the schemes was simulated 10 times randomly. Four types of vehicles are set in simulations, representing the human-driven car, connected and automated car, human-driven bus, and connected and automated bus. The basic attributes of each vehicle type can be seen in Table 4. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \multirow{2}{*}{**V-Type**} & **Length** & **Width** & **Acceleration** & **Deceleration** & **Car-** & **Lane-** \\  & **(m)** & **(m)** & **Ability** & **Ability** & **Following** & **Change** \\  & **(m)** & **(m/s\({}^{2}\))** & **(m/s\({}^{2}\))** & **Model** & **Model** \\ \hline H car & 5 & 1.8 & 2 & 4.5 & IDM & LC2013 \\ CA car & 5 & 1.8 & 2 & 4.5 & CACC & LC2013 \\ H bus & 10 & 2.5 & 2.6 & 4.5 & IDM & LC2013 \\ CA bus & 10 & 2.5 & 2.6 & 4.5 & CACC & LC2013 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: The basic attributes of four vehicle types. \begin{table}
\begin{tabular}{c c c} \hline \hline
**No.** & **Attribute of Bus Stop** & **Typologies** \\ \hline
1 & Distance to crosswalk & Near-side of crosswalk bus stop \\
2 & Location of the & Median bus stop \\  & cross-section & Curbside bus stop \\
3 & Form & On-line bus stop \\  & & Off-line bus stop (bus bay) \\
4 & Number of bus berth & Single-berth bus stop \\  & & Multi-berth bus stop \\
5 & Station design & Enclosed bus stop \\  & & Non-enclosed bus stop \\  & & Bus stop with grade-separated bus lanes \\
6 & Bus lane & Bus stop with at-grade bus lanes \\  & & Bus stop with non-exclusive bus lanes \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Classification criteria and specific typologies of bus stops. In addition, according to differences between CAVs and HVs in perception, decision-making, and control, CAVs have a significant advantage over HVs [50; 51]. According to the related research [52], the desired time headway during car-following and lane-changing of CAVs is set to be 1 s. When a CAV follows an HV, its longitudinal control model degrades into the Krauss model, which is also an HV car-following model. The specific parameters of car-following model and lane-change model are shown in Table 5, where H car refers to a car controlled and operated by a human driver; CA car refers to a car that utilizes advanced communication and automation technology to exchange and interact with real-time data between cars and other vehicles, transportation infrastructure and traffic management systems to improve driving safety, efficiency, and convenience; H bus is a bus controlled and operated by a human driver; and CA bus refers to a bus that uses advanced communication and automation technology to exchange and interact with real-time data between public transport vehicles and other traffic participants, infrastructure, and traffic management systems to improve the efficiency, reliability, and safety of the public transport system. The transit vehicles (including the served and waiting buses) dock at an overtaking prohibited bus stop, obey the first-in-first-out rule, and usually disperse independently from each other. For overtaking stops, without violating the principle of safe driving, the completed service bus can overtake the bus in service ahead to leave the station. The bus waiting for service can surpass the bus early to enter the vacant berth in front of the stop for parking.