# Real-Time Performance Measurement Application via Bluetooth Signals for Signalized Intersections
## 4 Discussion  
After obtaining the results of the Bluetooth-based performance measurement system designed in the study, validation studies are carried out. The Aimsun simulation program is used in verification studies. Traffic data during the day are obtained from the sensors and intersection control device at the Refik Cesur Intersection. In the study, the Refik Cesur Intersection is operated with a fixed-time signaling system on 15 May 2024, and a fully adaptive signaling system on 16 May 2024. Bluetooth-based performance measurement system data are also examined for these days. Direction-based vehicle counts and signal times for the 18:00-19:00 time interval on 15 May 2024 and 16 May 2024 were obtained from the sensors and intersection control device at the Refik Cesur Intersection. These data between 18:00-19:00 for both days were entered into the Aimsun simulation program. Thus, the outputs of the Bluetooth-based performance measurement system and the Aimsun simulation program were compared using data between 18:00-19:00 on 15 May 2024 and 16 May 2024. The Refik Cesur Intersection is modeled within this study. While creating the Aimsun model, many parameter entries and model drawing studies are carried out. Within the scope of the Aimsun model, inputs such as speed limits, turning lanes, number of lanes, lane and road capacity, road width, and signaling placement that affect traffic congestion are used. The calibration process of parameters such as driver reaction time, lane compliance level, driver behavior, and similar parameters for the driving model of the vehicles is carried out in line with the observations made at the intersection. In this study, inputs of other parameters used in the Aimsun simulation are also provided. The slopes of the roads joining at the intersection are assumed to be zero. In the simulations, the speed of vehicles entering the intersection is gradually reduced. Visible parking at the intersection is included in the simulation. The vehicle counts entered as data into the Aimsun simulation are the arrival directions of the vehicles, the exit directions of the vehicles from the intersection, and the total number of vehicles. Traffic count data and signal times between 18:00-19:00 on 15 May 2024 and 16 May 2024 were processed into the Refik Cesur Intersection, which is modeled exactly in the Aimsun simulation program. The model was run with the fixed-time program for vehicle counts on 15 May 2024, given in Table 1. Vehicle counts on 16 May 2024 were also run with varying signal times according to traffic conditions received from the fully adaptive signaling system. The vehicle counts processed at the Refik Cesur Intersection, modeled in the Aimsun simulation program, are given in Table 10 as an example for the date of 16 May 2024. The Aimsun model is modeled exactly with the previously explained inputs and operated as seen in Figure 11. Delay values for the Refik Cesur Intersection, which is operated in a one-to-one simulation environment with fixed-time and fully adaptive signal data, are taken as output from the Aimsun simulation program. \begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Traffic Flow**} & **Fixed Time—Traffic Flow** & **Fully Adaptive—Traffic** & **Fixed Time—Daily** & **Fully Adaptive—Daily** \\  & **Based Daily Average** & **Flow Based Daily Average** & **Average Delay per** & **Average Delay per** \\  & **Delay per Vehicle (s/veh)** & **Delay per Vehicle (s/veh)** & **Vehicle (s/veh)** & **Vehicle (s/veh)** \\ \hline Q5 & 57.6 & 43.1 & & \\ Q6 & 41.4 & 29.6 & & \\ Q7 & 91.5 & 78.4 & & \\ Q8 & 71.8 & 67.7 & 58.1 & 45.3 \\ Q9 & 59.9 & 58.3 & & \\ Q10 & 116.1 & 87.1 & & \\ \hline \hline \end{tabular}
\end{table} 
Table 9: Daily delay performances per vehicle.