University of Tehran Journal of Environmental Studies 1025-8620 Articles in Press 2026 04 19 Extraction of Driving Cycles on Southern and Southwestern Tehran Province Freeways and Their Potential Impact on Air Pollution Extraction of Driving Cycles on Southern and Southwestern Tehran Province Freeways and Their Potential Impact on Air Pollution 106590 10.22059/jes.2025.390121.1008584 FA Khosro Ashtafi Department of Environmental Engineering, University of Tehran, Tehran, Iran 0000-0001-8048-0275 Sajad Hakimi Department of Environmental Engineering, Faculty of Environment, University of Tehran, Tehran, Iran 0009-0001-1796-985X Amirhosein Merrikh Department of Environmental Engineering, Faculty of Environment, University of Tehran, Tehran, Iran 0009-0002-0709-9093 Arash Kouhi Department of Environmental Engineering, Faculty of Environment, University of Tehran, Tehran, Iran 0009-0009-4124-9965 Milad Saberi Department of Environmental Engineering, University of Tehran, Tehran, Iran 0009-0004-1042-7160 Journal Article 2025 03 15 Objective: In this paper, the driving cycle on three major freeways, Tehran-Qom, Tehran-Saveh, and Tehran-Karaj, has been analyzed and extracted. These cycles have not yet been calculated comprehensively or even separately, and our goal is to provide new and precise data regarding driving cycles on these routes. The obtained information can be used to improve transportation policies, help create the basis for reducing pollutants, and optimize driving behavior in the future.<br />Method: To conduct this study, a light passenger car and a GPS application on the driver’s cellphone were used. Vehicle speed data was collected at various time intervals along the selected routes. The data were then corrected using data-processing techniques and noise elimination. By employing MATLAB software and utilizing methods such as micro-trip analysis and k-means algorithm, optimal driving cycles were extracted both individually for each route and for the combination of freeways. This process was undertaken to provide an accurate depiction of driving behavior on these routes.<br />Results: The findings indicate that the extracted driving cycles exhibit significant fluctuations in speed and acceleration. These fluctuations may be influenced by factors such as traffic congestion, the occurrence of accidents, and road and weather conditions, and they reflect the dynamic nature of driving conditions in different environments. When compared to global standard driving cycles, the driving pattern on the studied routes shows lower positive and negative accelerations, which may indicate a more cautious or smoother driving style on these routes. Moreover, most drivers tend to maintain higher speeds, such that their average speeds are higher than those of the standard cycles. Another notable point is the high proportion of driving time on these routes, which indicates few stops along the way and contributes to increased travel efficiency. In addition, the analysis shows that drivers’ behavior is strongly influenced by road conditions, pavement quality, traffic flow, and changes in weather, highlighting the necessity of adapting driving strategies to varying environmental conditions in order to improve safety and efficiency. Conclusion: The results of this study indicate that accurate extraction of driving cycles on the main freeways of Tehran Province can be used as an effective tool for estimating pollutant emissions and designing air pollution reduction policies. The results of the research, together with the examination of similarities, confirm the high accuracy of the software in extracting driving cycles. The differences emphasize the importance of developing a driving cycle that is compatible with drivers’ behavior and the geographical conditions of each country, in comparison with other countries. Objective: In this paper, the driving cycle on three major freeways, Tehran-Qom, Tehran-Saveh, and Tehran-Karaj, has been analyzed and extracted. These cycles have not yet been calculated comprehensively or even separately, and our goal is to provide new and precise data regarding driving cycles on these routes. The obtained information can be used to improve transportation policies, help create the basis for reducing pollutants, and optimize driving behavior in the future.<br />Method: To conduct this study, a light passenger car and a GPS application on the driver’s cellphone were used. Vehicle speed data was collected at various time intervals along the selected routes. The data were then corrected using data-processing techniques and noise elimination. By employing MATLAB software and utilizing methods such as micro-trip analysis and k-means algorithm, optimal driving cycles were extracted both individually for each route and for the combination of freeways. This process was undertaken to provide an accurate depiction of driving behavior on these routes.<br />Results: The findings indicate that the extracted driving cycles exhibit significant fluctuations in speed and acceleration. These fluctuations may be influenced by factors such as traffic congestion, the occurrence of accidents, and road and weather conditions, and they reflect the dynamic nature of driving conditions in different environments. When compared to global standard driving cycles, the driving pattern on the studied routes shows lower positive and negative accelerations, which may indicate a more cautious or smoother driving style on these routes. Moreover, most drivers tend to maintain higher speeds, such that their average speeds are higher than those of the standard cycles. Another notable point is the high proportion of driving time on these routes, which indicates few stops along the way and contributes to increased travel efficiency. In addition, the analysis shows that drivers’ behavior is strongly influenced by road conditions, pavement quality, traffic flow, and changes in weather, highlighting the necessity of adapting driving strategies to varying environmental conditions in order to improve safety and efficiency. Conclusion: The results of this study indicate that accurate extraction of driving cycles on the main freeways of Tehran Province can be used as an effective tool for estimating pollutant emissions and designing air pollution reduction policies. The results of the research, together with the examination of similarities, confirm the high accuracy of the software in extracting driving cycles. The differences emphasize the importance of developing a driving cycle that is compatible with drivers’ behavior and the geographical conditions of each country, in comparison with other countries.