# Urban Traffic State Sensing and Analysis Based on ETC Data: A Survey
## 5 ETC-Based Urban Traffic Management: Applications and Practices
### Environmental Impact and Benefit Assessment  
ETC system applications in urban transportation require not only a consideration of technical feasibility but also a comprehensive evaluation of environmental benefits and economic value, which holds significant importance for policy formulation and system promotion. [PERSON] et al. comprehensively assessed the environmental and economic footprints of electronic toll collection lanes through simulation studies, using toll stations in the Thessaloniki metropolitan area of Greece as case studies, considering specific traffic characteristics, variable toll station configurations, and different penetration rates of ETC tag users for automobiles and heavy vehicles. Results demonstrated that when toll station right lanes are converted to ETC lanes, private vehicle penetration rates must exceed 15% and heavy truck penetration rates must exceed 20% to reduce traffic congestion and improve environmental conditions [58]. [PERSON] et al. conducted in-depth research on the safety assessment of toll plaza diverging areas, considering different vehicle toll collection types, noting that different vehicle toll collection types and different toll plaza distributions cause toll plaza diverging areas to become typical vehicle-weaving zones with frequent crossing behaviors and conflicts on highways. The research identified the influencing factors of four random parameters on conflict risks through developing random parameter ordered logit models. Results demonstrated that vehicle following patterns with identical toll collection types exhibit higher percentages of severe conflict risks, with an average acceleration of the following vehicles, lane marking indicators, initial vehicle lanes, and lane changes being significantly correlated with collision risk levels [59]. Regarding environmental pollution, [PERSON] et al. specifically investigated the effects of manual and electronic toll collection systems on highway particulate pollutant levels in Taiwan, conducting two-week sampling activities at toll stations in the Taipei metropolitan area, collecting indoor toll station monitoring samples from ETC and MTC lanes to assess the hourly concentrations of polycyclic aromatic hydrocarbons, PM1.0, PM2.5, and PM10. Results demonstrated that automobile and truck lanes with MTC exhibited higher average concentrations of particulate polycyclic aromatic hydrocarbons, PM1.0, and PM2.5, compared to ETC. PM1.0 and PM2.5 concentration increases per 100 vehicles in bus and truck lanes with MTC were approximately twice those of ETC. ETC technology provides solutions for traffic delay problems at toll stations in Taiwan and may more uniformly reduce polycyclic aromatic hydrocarbons, PM1.0, and PM2.5 particulate pollutant levels from highway traffic emissions compared to MTC [60]. [PERSON] conducted an in-depth exploration of global trends in highway electronic toll collection, Vietnam's experience, and policy implications. By analyzing the global ETC trendsand in-depth investigation of Vietnam's experience, practical policy insights were provided for developing countries facing this critical transition. A key feature of the research was the in-depth analysis of Vietnam's transition from manual toll collection to ETC, demonstrating significant improvements in emission reduction, operational efficiency, and cost and time savings. The research emphasized ETC's role in improving productivity, promoting sustainable development, reducing pollution, and advancing toward an intelligent economic society, highlighting the critical importance of government leadership and private sector cooperation in achieving successful ETC implementation [61]. [PERSON] et al. provided detailed reports on the operational benefits of electronic toll collection through case studies, investigating traffic operational improvements at Orlando-Orange County Expressway Authority electronic toll plazas.