# Dynamic Low-Emission Zones for Urban Mobility: A Systematic Review
## 4 Results
### Technological Innovations
#### 4.3.4 Privacy-Preserving Electronic Toll System with Dynamic Pricing for Low-Emission Zones [19]  
This study presents a novel electronic road pricing (ERP) system for Low-Emission Zones (LEZs) that enhances fraud detection and driver privacy through a robust dynamic pricing model. By leveraging cryptographic techniques and a prepayment mechanism, the system addresses key challenges in traditional ERP methods, including privacy concerns and fraud detection inefficiencies. Its key contributions are as follows:  
* Dynamic Pricing: Prices for LEZ stretches are dynamically adjusted based on real-time traffic volume, ensuring efficient flow management and fair pricing for drivers based on their emission category.
* Privacy Preservation: The system guarantees the anonymity of honest drivers using revocable anonymity protocols. Vehicle itineraries are encrypted and cannot be linked to specific users unless fraud is detected.
* Fraud Detection: Fraudulent drivers are identified through digital certificates and on-board unit (OBU) verification at checkpoints. Honest drivers are protected from false accusations by cryptographically signed records.  
* Scalability and Feasibility: The system is designed to function in urban environments with dynamic traffic conditions, providing robust fraud detection and privacy preservation without introducing excessive computational or infrastructural costs.
* Integration of Security Mechanisms: It incorporates tamper-proof modules and secure vehicle elements to ensure data integrity and authenticity throughout the tolling process.  
This ERP system exemplifies how advanced security and pricing mechanisms can enhance the operational efficiency and public acceptance of LEZs. By dynamically adjusting prices and ensuring privacy preservation, it aligns with the goals of dynamic LEZs to optimize emission reduction while maintaining equitable access to urban areas.  
3.5 Advancing Sustainability Impact Assessment: A Comprehensive Tool for Low-Emission Zone Management [30]  
A comprehensive tool for managing Low-Emission Zones (LEZs) is presented. It integrates real-time monitoring, air quality modeling, and advanced data analytics to support decision-making for urban sustainability. It has been validated in five European cities--Helsinki, Stavanger, Paris, Amsterdam, and Tallinn--and demonstrates significant potential for reducing emissions and improving urban air quality. Key contributions are as follows:  
* Real-Time Monitoring and Data Integration: Utilizes IoT sensors, cameras, and communication networks to collect hyperlocal data on vehicle emissions, traffic patterns, and compliance levels within LEZs.
* Advanced Air Quality Modeling: Incorporates CHIMERE-WRF chemical models and bilinear interpolation techniques to predict pollutant dispersion at a street-level resolution, enabling targeted interventions.
* Sustainability Impact Assessment: Provides key performance indicators (KPIs) and visualization tools to evaluate the environmental and traffic impacts of LEZ scenarios in real time.
* Validated Emission Reductions: Achieved up to 86% CO\({}_{2}\) equivalent reductions in Helsinki under optimal scenarios, demonstrating the efficacy of adaptive LEZ management strategies.
* Interactive User Interface: Includes simulation tools, heatmaps, and dashboards for defining and monitoring LEZ boundaries and optimizing policies based on contextual intelligence and real-time data.  
The tool exemplifies how advanced technologies and predictive analytics can enhance the adaptability and effectiveness of LEZ systems. By integrating real-time data and scenario simulations, it supports dynamic LEZ implementations, enabling policymakers to balance environmental goals with urban mobility needs.