A Multi-Stakeholder Information System for Traffic Restriction Management

Abstract

Background: In many urban areas, 80% to 90% of pollutant emissions are generated by road traffic, particularly from heavy vehicles. With the anticipated surge in e-commerce logistics, the need for effective urban mobility control measures has become urgent, focusing on traffic restrictions and efficient enforcement tools. This work introduces Log-ON, a multi-stakeholder information system designed to facilitate the implementation and management of sustainable traffic restrictions. Methods: The proposed system was developed through extensive literature reviews, expert consultations, and feedback from logistics fleet managers. User-centered mock-ups were created for various stakeholders, including the public, regulatory authorities, logistics operators, and enforcement agencies, ensuring that the system effectively addresses a diverse set of needs. Results: By taking into account a wide range of influencing factors, Log-ON functions as a decision-support tool designed to optimize access restrictions for vehicles, particularly heavy vehicles, in urban environments. Conclusions: Log-ON’s adoption promises significant improvements in urban mobility by reducing traffic-related pollution and fostering healthier, cleaner cities. However, traffic restrictions could increase delivery costs, potentially disrupting logistics operations. To address this, the development of new business models for last-mile delivery is essential, ensuring that sustainable traffic management strategies align with the economic challenges faced by logistics providers.

1. Introduction

Despite significant progress in improving overall air quality, Europe still faces concerning levels of air pollution [1]. The high pollution levels have a significant toll on public health, accounting for approximately 569,000 premature deaths annually in Europe [2].

In 2021, nearly 10% of the urban population found themselves exposed to PM₁₀ concentrations surpassing the annual limit value for human health protection established by the European Union (EU) (50 $\mathsf{\mu }$g.m⁻³), and 76% of the population exceeded the PM₁₀ protection values set by the World Health Organization (45 $\mathsf{\mu }$g.m⁻³). Furthermore, over 90% of the population faced exposure to NO₂ and PM_2.5 at levels that surpassed the World Health Organization’s protection guidelines.

In urban areas, traffic stands out as the primary source of air pollution. In high-traffic zones, vehicles account for approximately 90% of CO emissions, 80–90% of NO_x emissions, as well as HC and a significant amount of PM_x. Among these, heavy vehicles contribute substantially to emissions of PM_2.5, NO₂, and SO_x [3,4].

The levels of pollution within vehicles, the third most occupied microenvironment after home and workplace, are particularly concerning as these enclosed spaces can harbor elevated concentrations of pollutants, often surpassing those found in ambient outdoor air [5,6]. Marinello et al. [7] found that concentrations of particulate matter (PM) and total volatile organic compounds (TVOCs) within these microenvironments can, in some cases, reach several hundreds of µg.m⁻³, far exceeding recommended safety levels. Additionally, Ramel-Delobel et al. [8] concluded that users of motorized vehicles are the most highly exposed to gaseous pollutants, while public transport users experience the highest exposure to PM_2.5, and those using active transportation modes are most vulnerable to ultrafine particles (UFPs).

In response to these critical issues, the EU has set ambitious goals, including a 60% reduction in transport emissions by 2030 compared to 1990 levels, along with a 20% reduction relative to 2008 levels [9]. These targets underscore the urgent need to address transport pollution as part of a broader strategy to improve air quality and protect public health.

By 2050, it is estimated that approximately two-thirds of the world’s population will live in urban areas [10]. As urbanization accelerates, the challenges posed by traffic congestion and vehicle exhaust pollution are growing more acute. Besides emissions, an increase in noise levels and an increase in the risk of accidents and changes in the costs of urban logistics are also observed.

To address the adverse consequences of transportation in urban areas, which have been amplified by the surge in e-commerce demands during the COVID-19 pandemic [11], cities have implemented additional measures to restrict vehicle circulation [12,13]. Beyond curbing pollutant emissions, municipalities enforce these restrictions to enhance well-being, safety, and overall mobility convenience. However, traffic restrictions, such as one-way streets and dedicated lanes for public transport, often aimed at improving traffic flow, can paradoxically lead to increased travel distances and durations for specific modes of transport, particularly the transportation of goods [14].

To help municipalities improve traffic policies, the European Commission provides guidelines for Sustainable Urban Mobility Plans (SUMP) and Sustainable Urban Logistics Plans (SULP). Initiatives like ENCLOSE, NOVELOG, and SULPiTER offer methodologies to promote these plans. However, many European cities still lack comprehensive logistics plans [15], and municipalities often struggle with limited resources for plan development and assessment [16].

Logistics activities ensure goods are delivered and collected in the desired quantity, location, and time, often involving temporary cargo storage [17]. Public policies that restrict cargo vehicle movement affect both carriers, who face challenges in handling goods, and end customers, who may experience delays in receiving products. This disruption can directly impact urban economies, highlighting the need for tools that offer greater flexibility in traffic management.

While several applications have been developed to enhance traffic flow, to the best of our knowledge, there are currently no solutions that comprehensively support both cities and end-transport users in day-to-day traffic management. Thus, integrating various data sources and engaging multiple stakeholders is crucial for effective management. The primary goal of this study is to design a multi-stakeholder prototype system for the coordinated management of traffic restrictions in urban areas particularly tailored for last-mile logistics distribution in urban regions (although not limited to these vehicles). Considering various factors such as environmental and legal aspects, this integrated system aims to provide real-time comprehensive information, facilitating more informed decision-making processes.

To achieve these goals, we adopted a systematic approach that included a comprehensive literature review, consultations with transportation experts, and insights from fleet managers within a logistics company. This approach guided the design of distinct mock-ups for various user groups, ensuring user-friendliness and addressing the specific needs of different stakeholders.

The paper is structured as follows. First, it explores the concept of traffic restrictions and provides a review of monitoring, planning and management of transport applications. Next, it presents the Log-ON system along with its key policy implications. Finally, the paper concludes by summarizing the main findings of the study.

2. Traffic Restrictions

Aside from traffic restriction zones, daily events such as traffic accidents and unforeseen urgent tasks can also disrupt even the most meticulously planned schedules. Consequently, traffic restriction measures can be categorized as either temporary or permanent. Temporary measures are designed to manage traffic flow during sporadic events, such as construction, concerts, or emergency situations. In contrast, permanent measures aim to address ongoing issues like emissions, congestion, or logistics costs. Examples of permanent measures include Low Emissions Zones (LEZs) and Zero Emissions Zones (ZEZs), which impose stricter regulations on vehicle access within urban areas. These restrictions often limit access for high-pollution vehicles to certain zones or require them to pay a fee.

The concept of LEZ was first implemented in Sweden in 1996 [18]. Since the 1990s, traffic restrictions have proliferated across Europe, gaining particular popularity in southern European cities, including those in Italy, France, and Spain [19]. Presently, Europe boasts more than a thousand implemented or planned traffic restrictions, with over half of them located in Italy, a country known for its high levels of air pollution [20]. In many Italian cities, multiple LEZs exist, varying according to vehicle type, time periods, or specific environmental concerns. Figure 1 provides an overview of the number and types of restrictions planned or already in place in 2023 across various European countries and

Table 1. Examples of traffic restrictions in place or planned in 2023 in Europe [19].

Place	Scope	Description
Austria (Kärnten)	All vehicles	Emergency scheme aimed at reducing ${\mathrm{PM}}_{10}$ and ${\mathrm{NO}}_2$ emissions and improving air quality by lowering the maximum speed on the A2 South motorway, with drivers notified via roadside information boards.
Czech Republic (Brno)	All vehicles	Time-regulated ban for all vehicles. Vehicles providing deliveries, cyclists, and certain other vehicles can enter if they are allowed a permit.
England (London)	All (except vehicles with >8 seats)	Congestion charge which depends on the vehicle type and period of the day.
France (Paris)	All vehicles	From 2030 onward, Monday to Friday 8–20 h, all vehicles need a green Crit’Air sticker. Only electric and hydrogen fuel cell vehicles are allowed to circulate.
France (Toulouse)	Delivery vehicles	Restricted delivery time slots for all delivery vehicles. Electric vehicles and vehicles < 9 m in length can apply for extended delivery times. The stopping time is always 20 min. A parking disc for delivery vehicles is mandatory.
Germany (Berlin)	All vehicles	LEZ in place. The minimum standard is Diesel Euro 4, Petrol Euro 1/green sticker.
Greece (Athens)	Cars and lorries	There are two schemes. In the city center (small ring), vehicles, cars and lorries < 2.2 t are only allowed entry on alternating days, depending on the last digit of their license plate. The scheme is active from Monday to Thursday from 7–20 h and Friday from 7 to 15 h. For the whole Athens area (Big ring), vehicles > 2.2 t and buses need to meet the minimum standard: diesel Euro 5 (need to be registered). All-electric, hybrid, natural gas, Euro 6 and LPG vehicles are excluded from the restrictions.
Italy (Rome)	All vehicles except electric	LEZ called Fascia verde cover the entire city. From 1 November 2024, %MDPI: Please revise the date (format: Date Month Year), e.g., accessed on 1 January 2020. the minimum standard to be allowed to circulate in this belt from Monday to Saturday permanently is petrol Euro 4, diesel Euro 4, and mopeds, microcars, and motorcycles, Euro 3. There are also Ecological Sundays (specific days), when there no vehicles with a combustion engine are allowed to circulate from 07:30 to 12:30 and 16:30 to 20:30.
Ireland (Dublin)	Heavy goods vehicles with 5+ axels in place	Vehicles are banned from circulating daily from 7 to 19 h. A permit to enter this area can be granted to deliver or collect goods from a premises or construction site and to travel through the restricted area when are not permitted to use the Dublin Tunnel (e.g., wide-load or restricted goods).
Malta (Valletta)	All vehicles except motorbikes	Vehicles have to pay to enter in the city center certain times. The value is dependent on the length of time in the zone.
Netherlands (28 cities)	Logistic vehicles	A zero-emission logistics zone starts in 2025, with only zero-emission delivery vehicles allowed in the city center after 2030.
Poland (Wroclaw)	Lorries with >9 t	Lorries from 9–12 t are only allowed to enter the zone on the indicated streets: (i) >12 t: can enter the zone 4–6 h, 9–13 h, and 19–22 h, and (ii) >18 t: can enter the zone 4–6 h, 9–11 h, 20–22 h. Vehicles with >18 t without a travel destination in the zone are requested to turn back to avoid the city center.
Slovenia (Ljubljana)	All vehicles	Large pedestrian zone in the historic center with delivery access for loading and unloading between 6 and 10 h.
Spain (Sevilla)	All vehicles	Permanent access regulation in the historic center.
Sweeden (Gothenburg)	Lorries and buses	All lorries and buses are allowed in the LEZ that are Euro 6.

provides some examples of traffic restrictions implemented.

Light-duty vehicles, heavy goods vehicles, and buses are the vehicles that are usually restricted for circulation in LEZ areas. However, in some cities, the vehicles affected by the LEZ are not limited to these categories, varying according to the level of pollutant of the vehicle. In some LEZs, the installation of particulate filters may allow access to diesel vehicles [19]. The circulation of buses and heavy goods vehicles (generally more than 3.5 t of gross vehicle weight) are the most restricted vehicles [19].

The most common operating hours for urban access restrictions fall into two categories: permanent, which means they are in effect continuously (24 h a day, 365 days a year) and typically apply to specific vehicle groups, and daytime intervals that encompass a portion of the day and are applicable to all vehicles. Daytime slots, like those from 07:00 to 20:00, are often aligned with peak road traffic hours and can vary from country to country, accounting for commuter traffic patterns.

Several countries use sticker systems to control access to restricted areas (e.g., [21]). In Paris (Crit’Air) and Madrid (“emissions stickers”), access to restricted areas is managed through a windshield sticker system. These stickers are available in various colors, with their assignment primarily based on the car’s Euro class. Additionally, factors such as the vehicle’s tax class and the presence of a particulate filter are taken into account [22]. This system helps regulate and enforce access restrictions, contributing to ensuring compliance with environmental and traffic management policies.

Access control is also often implemented through intelligent video cameras that perform automatic recognition of the vehicle’s license plate (ANPR—Automatic Number Plate Recognition). These video cameras continuously capture images of all vehicles and use databases to verify whether the vehicle is allowed to drive in the area or not. This system is widely used in Belgium and is also adopted by London’s LEZ. For vehicles registered in Belgium, the cameras compare the registration number with the vehicle registration data to verify that the vehicle’s technical characteristics (Euro class) comply with the LEZ legislation. In case of non-compliance, a fine is imposed on the owner of the vehicle [23,24].

3. Applications for Transport Management and Planning

Over the last three decades, a variety of traffic management and planning systems have been developed to effectively manage urban traffic, including the management of traffic restrictions. These systems typically feature traffic signal control, commonly known as Urban Traffic Control (UTC). Beyond signal control, these systems also utilize strategic road space management techniques, such as traffic signal optimization, public transport prioritization, lane assignments, parking controls, turning restrictions, one-way streets, and tidal flow schemes. These capabilities allow for adaptive traffic planning that can dynamically manage and enforce traffic restrictions in response to varying traffic conditions.

UTC systems have become standard practice in large cities, where the integration of Intelligent Transportation Systems (ITSs) has further enhanced their ability to manage traffic restrictions. By incorporating technologies like traffic delay and congestion monitoring, automatic incident detection, knowledge-based control systems, and dynamic origin-destination estimation, these systems have become increasingly “smarter”. As a result, UTC systems now range from centralized (e.g., SCOOT [25]) to decentralized (e.g., SCATS [26]) and distributed approaches. A comprehensive review of traffic control strategies across different levels of control scope is provided by Vilarinho et al. [27].

In addition to traditional traffic management systems, a new wave of routing, search, and visualization applications has recently emerged, catering to transport end users. These include Waze [28], launched in 2008, Citymapper [29] in 2011, Here WeGo [30] in 2014, and Google Maps [31] in 2015.

Today, a wide range of traffic applications serve not only passenger cars but also public transportation, freight vehicles, and delivery services, offering advanced traffic planning capabilities. These applications have gained widespread popularity, revolutionizing how people navigate and interact with transportation networks by providing real-time information on various traffic conditions. Table 2 lists some examples of these traffic applications, highlighting their features and scope.

Among transport end users, traffic congestion is typically the most frequently used factor for route planning. Real-time data from GPS devices are collected by the phone devices and utilized by applications like Google Maps [31] and Waze [28] to suggest alternative routes. Delivery-focused applications, such as GSM Tasks [32], also leverage this real-time traffic information to optimize delivery planning.

Beyond traffic congestion, some applications provide information on other types of restrictions, such as the location of accidents and radars, roadworks, and close roads (e.g., [31]). However, only a few provide detailed information about these restrictions. Exceptions include Waze [28], which collects user feedback to offer specifics like the duration and description of restrictions, and Here WeGo [30], which supports drivers by providing, for instance, the expected end date of roadworks, facilitating more effective route planning.

Applications focused on heavy vehicles, such as Road Lords [33] and Sygic Truck [34], take this a step further by incorporating restrictions related to vehicle weight and height, making them particularly valuable for freight transport. Similarly, delivery-focused applications like Routific [35] enable route planning based on factors such as time windows, stop priorities, driver breaks, and shift times.

However, one significant and often overlooked gap in traffic applications is the identification of LEZs. A notable exception is TomTom GO Expert Plus [36], which offers advanced features such as clear LEZ avoidance and customizable settings for vehicle weight, height, and tunnel restrictions. Additionally, the Urban Access Regulation Route Planner application allows users to search for traffic restrictions specific to vehicle types within a particular city [19]. However, this application is not a comprehensive route planner tool, as it focuses solely on providing information about LEZs.

While some applications, like Google Maps and Waze [28,31], provide restriction information for the entire visible area on the screen, others, such as MapQuest [37], limit this information to the suggested route. Moreover, applications like Circuit [38] and Yandex [39], though synchronized with traffic restrictions, often fall short in visually communicating critical information, such as access restrictions, directly to the driver in a clear and accessible manner. This distinction highlights the varying levels of detail and user assistance offered by different traffic applications.

In addition, the literature review highlights that although some logistics applications, like Circuit [38], operate in conjunction with third-party logistics (3PL) providers and are connected to various third-party platforms, non-logistic route planners are not integrated with local authorities, such as municipalities or enforcement agencies, in order to create an effective environment for traffic restrictions. This lack of integration represents a significant limitation in the current state of the art.

Table 2. Examples of route planning applications in place in 2024 that consider traffic restrictions.

Ref.	Application	Scope	Location	Cost	Description
[40]	BigChange	Light vehicles	UK	Paid	Alerts drivers when entering an LEZ or other restricted areas and notifies customers about potential delays.
[38]	Circuit	Deliveries	Global	Paid	Synchronized deliveries considering traffic restrictions. Allows the connection to 3rd-party platforms.
[29]	Citymapper	Public transport and bicycle	Some world cities	Free	Provides reports on restrictions related to the use of public transport.
[28]	Waze	Light vehicles	Global	Free	Identifies the location of roadworks, accidents and roads blocked. Details such as as the duration and the description of the event are provided.
[31]	Google Maps	Light vehicles, public transport, bicycles	Global	Free	Identifies the location of roadworks, accidents and roads blocked.
[32]	GSM Tasks	Deliveries	Global	Paid	Allow to plan deliveries considering real-time information as roadblocks.
[30]	Here WeGo	Light vehicles, motorbike, bicycle	Global	Free	Identifies traffic restrictions such as congestion, speed cameras, roadworks, accidents, and blocked roads. For some, like roadworks, it also provides the expected end date and a description of the event.
[41]	Mappr	Deliveries	Global	Free	Allow to plan deliveries considering real-time information.
[37]	MapQuest	Light vehicles	Global	Free	Identified the location of some types of traffic incidents.
[42]	Tom Tom Go	Light and duty vehicles	Global	Paid	Identified roadworks.
[36]	TomTom GO Expert Plus	Light and duty vehicles	Global	Paid	Identified several types of road and traffic restrictions including weight and height restrictions and LEZ zones.
[33]	Road Lords	Heavy vehicles	Global	Free & paid	Identified weight and height restrictions.
[35]	Routific	Deliveries	Global	Paid	Allow planning deliveries considering restrictions such as time windows, stop priorities, driver breaks, and shift times.
[34]	Sygic Truck	Heavy vehicles	Global	Paid	Identification the location of accidents, roadworks, road blocks and weight restrictions. Three-dimensional navigation system.
[39]	Yandex Maps	Light vehicles, public transport, bicycle, scooter	Global	Free	Has real-time updates on traffic, road accidents, road work, closure roads, and speed radar, but the information is not provided in the map.

Table 2. Examples of route planning applications in place in 2024 that consider traffic restrictions.

Ref.	Application	Scope	Location	Cost	Description
[40]	BigChange	Light vehicles	UK	Paid	Alerts drivers when entering an LEZ or other restricted areas and notifies customers about potential delays.
[38]	Circuit	Deliveries	Global	Paid	Synchronized deliveries considering traffic restrictions. Allows the connection to 3rd-party platforms.
[29]	Citymapper	Public transport and bicycle	Some world cities	Free	Provides reports on restrictions related to the use of public transport.
[28]	Waze	Light vehicles	Global	Free	Identifies the location of roadworks, accidents and roads blocked. Details such as as the duration and the description of the event are provided.
[31]	Google Maps	Light vehicles, public transport, bicycles	Global	Free	Identifies the location of roadworks, accidents and roads blocked.
[32]	GSM Tasks	Deliveries	Global	Paid	Allow to plan deliveries considering real-time information as roadblocks.
[30]	Here WeGo	Light vehicles, motorbike, bicycle	Global	Free	Identifies traffic restrictions such as congestion, speed cameras, roadworks, accidents, and blocked roads. For some, like roadworks, it also provides the expected end date and a description of the event.
[41]	Mappr	Deliveries	Global	Free	Allow to plan deliveries considering real-time information.
[37]	MapQuest	Light vehicles	Global	Free	Identified the location of some types of traffic incidents.
[42]	Tom Tom Go	Light and duty vehicles	Global	Paid	Identified roadworks.
[36]	TomTom GO Expert Plus	Light and duty vehicles	Global	Paid	Identified several types of road and traffic restrictions including weight and height restrictions and LEZ zones.
[33]	Road Lords	Heavy vehicles	Global	Free & paid	Identified weight and height restrictions.
[35]	Routific	Deliveries	Global	Paid	Allow planning deliveries considering restrictions such as time windows, stop priorities, driver breaks, and shift times.
[34]	Sygic Truck	Heavy vehicles	Global	Paid	Identification the location of accidents, roadworks, road blocks and weight restrictions. Three-dimensional navigation system.
[39]	Yandex Maps	Light vehicles, public transport, bicycle, scooter	Global	Free	Has real-time updates on traffic, road accidents, road work, closure roads, and speed radar, but the information is not provided in the map.

4. The Log-ON System

The primary objective of the Log-ON prototype is to design a multi-stakeholder system for the coordinated management of traffic restrictions in urban areas. This system is designed to enhance adaptability and user coordination, enabling a more effective design and assessment of traffic restrictions, particularly those related to air quality, and facilitating seamless information exchange among various stakeholders. By addressing these objectives, the Log-ON prototype aims to create a more efficient, environmentally conscious, and collaborative framework for urban traffic management.

The next subsections present the requirements identified to develop a system prototype to address these objectives and the main concepts defined. After that, the components and the main functionalities are outlined.

4.1. Requirements

The identification and specification of requirements were carried out according to the needs of the stakeholders of the system. Based on the literature review, four stakeholders were considered:

• Logistic operators: This entity includes the drivers/operators (Os) as well as the fleet managers (Gs). Drivers need access to provided authorizations for driving in areas with limited access. Additionally, the fleet managers carry out the service planning, including the definition of stops and routes. They are primarily responsible for the operations associated with the distribution of goods and for the quality of service. One of their needs is to have prior access to traffic restrictions in order to optimize the planning of the services provided to their customers.
• Regulatory authority (R): entity responsible for spatial planning and management of a road, city or metropolitan area. It is responsible for encouraging the development of the urban environment. Its main interest is to minimize societal and environmental impacts, ensuring sustainable urban growth and enhancing the overall quality of life for residents.
• Road enforcement authority (E): entity responsible for inspecting and complying with the legal framework, with a view to public welfare and the defence of the interests of citizens and economic operators. This entity is therefore also responsible for ensuring the safe movement of transport in the urban area in question. The main need of these authorities in the development of this system is to understand if there are vehicles circulating without authorization in a certain area of the city subject to a traffic restriction.
• General public: ordinary citizens who live and/or work in the urban center. These citizens should have access to all information about restrictions in the urban center.

An iterative process has proceeded to identify incompatibilities and implement the necessary adjustments. To guarantee the validity and accuracy of the process, weekly meetings were held with specialists in different areas of transport, information systems and environmental assessment. Fleet managers from a logistics company were also consulted.

The requirements elicitation were described according to (i) the code and description of the requirement, (ii) the intended functionality, (iii) the necessary input data or activity that leads to the realization of the respective requirement, (iv) the list of operations how the system must perform, and (v) the output obtained after implementing the respective requirement. The degree of priority which takes into account their importance for the functioning of the system, was defined from High (+++) to Low (+).

Table 3. The requirements of the Log-ON prototype.

Phase	ID	Requirement	Actor	Priority
1. Collection, pre-entry, processing of data	R1.1	System data	R, S	+++
	R1.2	Information retrieval	S	+++
	R1.3	Invalid data identification	R	++
	R1.4	Information search	All	++
2. Management of restrictions	R2.1	Definition and management of vehicle traffic zones	R	+++
	R2.2	Definition and management of scenarios to be applied in traffic restrictions	R	++
	R2.3	Classification of logistics distribution vehicles to be considered in traffic restrictions	R	+++
	R2.4	Definition and management of traffic restrictions rules, considering traffic zones, scenarios and vehicle classes	R	+
	R2.5	Traffic restriction reporting	R	++
3. Management of requests	R3.1	Submission of requests for access to one or more zones with traffic restrictions	G, R	+++
	R3.2	Assessment and notification of access requests	R, O, G	+++
4. Monitoring & evaluation	R4.1	Calculation of spatio-temporal statistics of the urban environment	R	++
	R4.2	Automatic learning of movement restriction rules	S	+
	R4.3	Irregularity alert	E, R	+++
	R4.4	Driving restriction recommendation	R	+++
5. Visualization	R5.1	System data visualization	E, R, O	+++

Type of actor: R: Regularity Authority, O: Operator, G: Fleet Manager, E: Road enforcement authorities, S: System. Degree of priority: High (+++), Medium (++), Low (+).

list the requirements of the Log-ON prototype.

The initial requirements of Data entry and Information retrieval are of high importance for the functioning of the system as they are responsible for the existence of information in the system’s database. These data are pre-processed so that only valid information is stored in the system’s database. In the management of restrictions, the definition and management of traffic areas as well as the classification of distribution vehicles are requirements of high importance as they represent one of the main functionalities and objectives of the system. Likewise, order management should also be a priority given that it constitutes the bridge between two types of users, and it is what will allow flexibility and dynamism in controlling the access of certain vehicles to certain restricted areas. Alerts for irregularities and recommendations of restrictions also contribute to the dynamism and urban management of the municipalities, requirements that come from continuous and automatic learning of the rules that, over time, are manually created by a user. Last, information needs to be represented in a clear and intuitive way so that the user can use it efficiently.

4.2. Main Concepts

In the Log-ON prototype, four main concepts were considered:

• Restriction: a measure created by a regularity authority that aims to regulate the access of a certain type of vehicle to a certain zone, in a certain period of time. Restrictions depend on their type and duration. Each constraint is associated with a color that defines a long-term constraint, i.e., several weeks or months (in red); medium duration, several days (in orange); or short duration, a few hours (in yellow).
• Restriction type: place to which a restriction is associated. The place can be an area, a specific street or a point.
• Request: request for circulation authorization, by the driver or the fleet manager of a transport company, in an area where there are circulation restrictions.
• Authorization: response to a request made by the logistic operator.

Figure 2 presents, on the right side, the four types of stakeholders of the system, while on the left side are the types of restrictions.

4.3. System Architecture

The Log-ON prototype relies on five main components: Data sources, Staging area, Data provider, Processor, and Front-end Tools. Figure 3 shows the data flow diagram of the prototype. Each component was designed based on established theoretical conceptual frameworks that support its functionality as follows.

• Data Sources: This component encompasses various data structures that provide essential information to the system. The selection and integration of data sources are guided by Data Management Theory, which emphasizes the importance of data quality, relevance, and integration for effective system performance.
• Staging Area: The Staging Area involves tasks such as filtering, normalization, and deriving new information. This component is informed by Data Transformation Theory, which focuses on the processes required to prepare raw data for analytical purposes. This theory supports the need for pre-processing steps to ensure data accuracy and consistency.
• Data Provider: This component handles data storage and retrieval. It is grounded in Database Management Theory, which addresses the principles of data storage, indexing, and retrieval mechanisms. This theory ensures that data are efficiently stored and can be quickly accessed when needed.
• Processor: The Processor includes the computational environment capable of performing all functions described in the requirements. Computational Theory, which involves algorithms and computational models that support data processing and analysis, supports this component, ensuring that the system can handle complex computations and data manipulations effectively.
• Front-end Tools: The interfaces for data visualization and exploration are managed by the Front-end Tools component. This component is supported by Human–Computer Interaction (HCI) Theory, which emphasizes the importance of designing intuitive and user-friendly interfaces that facilitate effective data visualization and user interaction.

The Data Sources component of the prototype incorporates a variety of inputs crucial for effective traffic and air quality management. Primary traffic data are gathered from geographical information systems and various traffic sensors, including loop detectors, radar sensors, camera surveillance, and GPS devices. These sources provide essential details on road signage, traffic flow, and vehicle speed, which are critical for analyzing real-time traffic conditions and patterns. For air quality monitoring, data are collected from automatic air quality stations strategically located throughout the urban area and centrally managed by environmental authorities. These stations deliver continuous measurements of pollutants such as ${\mathrm{PM}}_{10}$, ${\mathrm{PM}}_{2.5}$, and ${\mathrm{NO}}_2$, offering valuable insights into the impact of traffic on air quality.

Since primary data are typically collected at specific points, the Processor component of the Log-ON system is responsible for generating additional information by integrating the primary data collected with secondary sources. Secondary data come from traffic simulation models like SUMO (Simulation of Urban MObility) or VISSIM (Multimodal Traffic Simulation Software), which provide insights into traffic behavior under various scenarios. For air quality, models such as ADMS (Atmospheric Dispersion Modelling System) or AERMOD (Air Quality Dispersion Modeling) simulate and predict pollution levels based on diverse traffic and environmental conditions. By synthesizing both primary and secondary data, the Log-ON system enables comprehensive analysis, supporting the development of effective strategies for urban mobility management and air quality improvement through scenario evaluation and strategic planning.

The system comprises a webpage and two apps. The webpage is accessible to all stakeholders with varying levels of information access. This interface accommodates the system’s full range of functionalities. Users can access restrictions and several statistics without authentication. Alternatively, authentication is required for more targeted access, specifically tailored for regulatory authorities and operators (fleet managers). Through authenticated access, these users can delve into specific information and use advanced functionalities provided by the system. The mobile application is intended for drivers and authorities responsible for road enforcement. As with the web application, both users have access to different features, requiring the use of credentials.

4.4. Functionalities

The proposed prototype is structured around six major execution functionalities: Data acquisition, management of restrictions, request management, monitoring and evaluation, and visualization. Figure 4 presents the system’s operating diagram, its requirements and the way in which the different functionalities are interconnected.

Data acquisition, pre-processing, and storage are facilitated by Extraction, Transformation, and Loading (ETL) processes, encompassing essential tasks for gathering valuable data for the Log-ON system. To ensure data quality, verification and data processing functionalities are employed. The visualization feature supports the analysis of diverse data types, including geospatial data.

Different mock-ups were created for each of the system’s users. For interface design, Figma (https://www.figma.com/ (accessed on 28 February 2024)) was utilized as the primary tool, enabling the creation of intuitive and user-friendly interfaces within the proposed system.

4.4.1. Restrictions Management

The Restriction Management feature empowers users in orchestrating mobility restrictions within urban environments. Within the urban space manager interface (located in the upper corner), various options are available, including the ability to create, edit, delete, or view reports concerning traffic restrictions. Users can also delve into statistics related to air quality, vehicle flow, and access authorization requests.

Figure 5 showcases a series of menus designed to define the restriction type, spatial domain, time constraints, and vehicle specifications for each imposed restriction. These menus provide comprehensive control, ensuring the precise configuration of each restriction in the urban landscape. Figure 6 displays the interface to edit constraints. The primary goal of these interfaces is to empower users to efficiently manage the restrictions they are interested in. To enhance the application’s usability, we have streamlined the user experience by incorporating consistent design elements across different interfaces.

Each restriction is categorized by its type, such as “Christmas interdiction” or “Congestion charge”, which helps in effective constraint management. Users have the flexibility to choose an existing typology from the provided list or create a new constraint typology.

For each restriction, a specific area with the constraint needs to be defined directly selecting it in the map (spatial domain menu). Alternatively, they can search or choose a recently used location. On the temporal front, users have the flexibility to select one or multiple time periods, along with a filter for specific days of the week. Additionally, users can define the frequency of the restriction according to their requirements.

Users can specify the types of vehicles impacted by the restriction by using the vehicles details menu. While the system primarily focuses on vehicles for heavy goods transport, for statistical purposes and public accessibility, it has been extended to include all types of motor vehicles. Users have the flexibility to select one or multiple vehicle types and indicate the Euro class limit that will not be allowed access. For instance, choosing Euro 2 implies that vehicles with Euro 1 and Euro 2 classifications will be affected by the restriction. Additionally, users can define the vehicle dimensions and specify the maximum number of vehicles permitted to enter the area simultaneously within a specific timeframe.

For editing constraints, users can leverage the filters available in the left menu of Figure 6 to easily locate and manage the specific restriction(s) they are looking for, ensuring a seamless and intuitive navigation experience.

4.4.2. Request Management

The Request Management module facilitates the creation, oversight, and monitoring of requests for road access to restricted zones. Regulatory authorities primarily handle request management in an automated fashion. Users have the ability to view requests that have been approved, declined, or are currently in a pending state, necessitating manual authorization (refer to Figure 7). Detailed information for each listed order is available, allowing users to delve into specifics. For instance, if an order is pending, users can access the reason behind its pending status, enhancing transparency and clarity in the process.

In the mobile application, the driver (or the fleet manager) can request authorization to access areas with traffic restrictions (option New Request in Figure 8b). The request must be accompanied by the vehicle identification, location and period of access. In this set of interfaces, the user can search the map in order to consult the restrictions that are currently active. The map view can be changed from satellite mode to a map, and the user’s current position can be viewed. These users can consult their request history (menu Requests in Figure 8c). This functionality gives access to all orders made with the option to filter the orders they want to consult.

Enforcement authorities can only consult restrictions that are currently active and check whether a given vehicle is authorized to circulate in its current location depending on its registration number (Figure 8a). On the other hand, logistics operators can search for restrictions, request a new access request (Figure 8b) and query the order history (Figure 8c).

4.4.3. Monitoring and Evaluation

The Monitoring and Evaluation feature plays a crucial role in effective urban space management by tracking vehicle movements and their impacts through a set of key indicators. These indicators are derived from interconnected traffic and air quality models running in the background. By integrating these models, the system provides comprehensive insights into the effects of urban mobility, offering decision-support recommendations essential for informed decision-making and efficient urban planning.

To facilitate this monitoring, the Analysis menu offers a comprehensive set of statistics, allowing users to select from various indicators (Figure 9a). For instance, users can access detailed insights into mobility metrics such as traffic flow, average speed, and vehicle density. In areas with traffic restrictions, the system provides data on vehicles that successfully entered restricted zones with authorization, those whose access was denied, and the total number of issued orders, regardless of the outcome. These statistics offer valuable insights into the number of vehicles operating within restricted zones during a selected period. Additionally, users can customize queries based on specific vehicle categories and defined Euro classes, enabling a detailed analysis of traffic patterns and the effectiveness of the restrictions. This customizable approach ensures a nuanced understanding of vehicle movements within restricted areas and their broader impacts.

At the environmental level, traffic impacts are monitored through air quality assessments. Using observed pollution levels from the air quality network and integrated air quality models, decision-makers can define traffic scenarios to evaluate the effects of different traffic management strategies on both mobility and environmental conditions.

The system also provides information on pollutant concentrations for several standard pollutants, such as CO, PM_2.5, PM₁₀, and NO_x, along with an Air Quality Index (AQI). For example, Figure 9b illustrates air quality levels, displayed using a color spectrum ranging from red (indicating poor air quality) to dark green (indicating very good air quality). Users can explore specific locations on the map, each associated with one or more dominant pollutants, offering a comprehensive overview. Additionally, the system allows users to track air quality trends for the upcoming week at a selected point or area, accessible through the bottom left menu. This detailed interface equips users with dynamic information, empowering them to make well-informed decisions in air quality management.

5. Policy Implications

Oporto city served as a case study to showcase the system, but the Log-ON system is intended for broader application in various urban areas. High-priority zones can be identified primarily based on traffic density and pollution levels. For a comprehensive evaluation, the AQI, which integrates data on multiple pollutants, can be utilized for a first analysis. However, to ensure the precise monitoring of high-priority zones, it is essential to assess each pollutant individually. The health protection standards set by international organizations such as the World Health Organization (WHO), the U.S. Environmental Protection Agency (USEPA), and the EU must be used as reference. For example, the EU through Directive 2008/50/EC specifies limit values for PM₁₀ at 50 µg.m⁻³ for the daily average and 40 µg.m⁻³ for the annual average to protect human health.

The Log-ON system offers significant advantages in traffic management and information accessibility, but it also presents challenges related to operational costs and potential delays. Achieving an optimal balance between these benefits and drawbacks requires careful consideration and skilled management.

One of the key benefits of the Log-ON system is its ability to centralize traffic restriction management at the city level within a single platform. This centralization not only enhances information accessibility but also streamlines control and enforcement processes.

By consolidating the city-level and traffic restrictions management into one system, the need for information transfer between different systems is reduced, minimizing the risk of data loss and ensuring more efficient and accurate management. However, to fully realize the benefits of Log-ON, the system must ensure interoperability with broader applications, allowing for seamless integration and coordination across platforms with a larger spatial domain or scope.

The system’s ability to deliver real-time data on the number and types of vehicles within a specific zone, combined with insights into their impacts, empowers authorities to design more effective restrictions. By considering factors such as vehicle quantity, type, age, and fuel type, this approach allows for the creation of restrictions aligned with the “polluter pays” principle, enabling more targeted and impactful measures. As a result, the system is not only capable of addressing existing challenges but also fosters more efficient, equitable, and environmentally sustainable urban mobility solutions.

Although the implementation of the Log-ON system is anticipated to significantly mitigate the overall impact of traffic restrictions, the real-time monitoring of these restrictions may suggest that adjustments are required. With this system, regulatory authorities have access to real-time information, enabling more effective traffic management adjustments. Moreover, by simultaneously monitoring traffic flow and air quality levels, the Log-ON system is expected to enhance the overall quality of life in urban areas. This integrated approach not only improves traffic management but also contributes to a healthier, more sustainable urban environment.

Additionally, the Log-ON system provides crucial information on active restrictions to the drivers, particularly the presence of LEZ or other restrictions, thereby preventing potential inconveniences. This feature represents a significant enhancement compared to other route planning applications, where such information is often missing, as is the case with popular apps like Google Maps [31], Waze [28], and Here WeGo [30].

Besides its positive impacts, negative impacts are also expected. For instance, logistics operators will face challenges, including mandatory fees and potential increases in energy and personnel costs due to altered routes when restrictions are available. These increased operational costs are likely to be passed on to the consumers, possibly leading to higher prices for online shopping. Consequently, this may incentivize consumers to opt for physical stores instead of online shopping, thus impacting the e-commerce market.

In addition, if the restrictions increase, the system might lead to delays in deliveries to consumers. These delays could occur when drivers encounter restrictions for which they lack authorization, forcing them to change routes, modes of transport, or times to delivery, possibly choosing not to pay associated fees. These changes could result in disruptions to the delivery, affecting the overall customer experience.

The effective adoption of such a system hinges significantly on the collaboration of all stakeholders, including regulatory authorities, enforcement authorities, and logistic operators. Therefore, harmonious cooperation among all stakeholders is essential to maximizing the system’s benefits and ensuring its successful integration into the urban environment.

6. Conclusions

In this work, we present Log-ON, a multi-stakeholder prototype information system designed to integrate authorities and end users into a centralized platform for more effective management and planning of traffic restrictions. This system serves as a decision support tool, helping to formulate traffic restriction measures that improve urban road traffic management while also considering environmental impacts. Although the primary focus of this study is on managing restrictions for vehicles carrying heavy goods in urban areas, the system’s applicability extends beyond this vehicle category.

Log-ON emphasizes providing information on various types of restriction zones, with a particular focus on LEZ, which is a gap in existing route planners. Moreover, in this system, the traffic restriction control of a city is centralized within the proposed application, facilitating improved transport management and planning for the different stakeholders: regulatory authorities, traffic enforcement agencies, logistics operators (drivers and fleet managers), and end users.

With the Log-ON system, authorities have access to a comprehensive dataset provided by traffic and air quality models running in the background, which enables them to assess various scenarios based on specific issues. Logistics operators and end users benefit from detailed information, allowing them to better plan their daily activities. Additionally, enforcement authorities can access information on authorized vehicles and report violations in real time.

An architecture that collects, prepares, and analyzes data on traffic and air quality, based on a theoretical conceptual framework, was defined. This allowed us to define three interconnected applications (mock-ups). a web application and two mobile applications, each tailored to different types of stakeholders. The web application is aimed at regulatory authorities, fleet managers of logistics operators, and end users, while the mobile applications are designed for vehicle drivers and road enforcement authorities. A set of system concepts and common elements was defined for all applications.

The systematic approach followed was considered robust for identifying the stakeholders and their needs, as well as the system requirements. The methodology was based on a comprehensive literature review of the problem, with a particular focus on European research projects, and consultations with experts in the field. This approach ensured that the Log-ON system is effectively tailored to meet the demands of urban mobility regulation.

Positive and negative impacts associated with the use of the Log-ON system were identified. While the quality of life in urban spaces is expected to improve, logistics operations may be disrupted, and delivery costs may rise. However, negative impacts could be minimized by introducing new eco-friendly vehicles or developing new business models for last-mile delivery, particularly through collaborative delivery models.

Future work encompasses the development of additional features to further enhance the system’s capabilities. This includes refining the decision support tools to better assist in defining more robust traffic restriction measures. Additionally, a pilot project in an urban setting is planned to validate and refine the system’s effectiveness.