NTUA Professor George Yannis contributed actively at the Scientific Workshop on: “Should we promote a 30 km/hr speed limit in cities?” organised by the Chair of Transportation Systems Engineering of the Technical University of Munich (TUM) which was held in Munich on July 6th, 2023. The Workshop hosted vivid discussions from Key – Experts on the different dimensions and perspectives of city-wide 30 km/h speed limit . Professor George Yannis contributed two key-note presentations:

•  Why city-wide 30km/h speed limit?
•  Artificial Intelligence, Big Data & Road Safety

ITS America, ERTICO and ITS Asia-Pasific are co-organising the 31th ITS World Congress which will be held in Atlanta, on 24-28 August 2025. ITS World Congress is the forum to make meaningful connections, experience inventive conference program presented by industry experts, and see cutting-edge technology in the Exhibit Hall. ITS World Congress allows the smart mobility community to come together to explore the deployment of intelligent transportation technologies that saves lives, improves mobility, promotes sustainability, and increases efficiency and productivity.​ 

The World Road Association – PIARC implemented an ambitious PIARC Knowledge Exchange project, aiming at sharing knowledge about road safety, with the active contribution of NTUA and AIT, especially within Low and Middle Income Countries with limited resources but also in more developed economies with different needs and priorities. The theme of this month refers to Vulnerable Road Users (VRUs), as presented by the PIARC Technical Committee 3.1 member Lawrence Chauke. Throughout the year, PIARC will focus on the Safe System approach, addressing safe roads and roadsides, safe road users, safe vehicles and safe speeds.   

Basic characteristics of road fatalities in Greece for the period 2012-2021 are summarised in a comprehensive infographic prepared by the NTUA Road Safety Observatory (data source: ELSTAT). According to these time series data, a spectacular decrease in road fatalities for pedestrians (-54%), inside(-56%) and outside built-up areas (-53%) was observed during the last decade. On the contrary, there was a large increase in the number of fatalities during daylight (+67%) and that needs to be considered.  

The European Commision welcomes the political agreement reached between the European Parliament and the Council on a proposal made by the Commission in 2021 on the revision of the Intelligent Transport Systems (ITS) Directive.  A smarter and interoperable transport system allows the more effective management of traffic and mobility across transport modes, enabling users to better combine the most sustainable modes of transport.  

According to data of the Hellenic Statistical Authority, 38 Greek cities recorded zero road fatalities inside build-up areas (excluding motorways) for at least one calendar year during the decade 2012-2021. Some cities recorded zero fatalities multiple times, such as the Municipality of Vyronas (9 years) and the Municipality of Kalamaria (7 years). The interactive map shows the road fatalities inside build-up areas (excluding motorways) of cities with population above 50,000 inhabitants, which account for 27% of road fatalities in Greece. 

The World Road Association – PIARC implemented an ambitious PIARC Knowledge Exchange project, aiming at sharing knowledge about road safety, with the active contribution of NTUA and AIT, especially within Low and Middle Income Countries with limited resources but also in more developed economies with different needs and priorities. The theme of this month refers to Data, as presented by the PIARC Technical Committee 2.4 “Road Network Operation/ ITS” Secretary Kaouther Machta. Throughout the year, PIARC will focus on the Safe System approach, addressing safe roads and roadsides, safe road users, safe vehicles and safe speeds.   

The International Commission for Driver Testing (CIECA) organised with great success the 55th CIECA Congress, which was held in Vienna, on 23-26 May 2023. With this congress, titled “What do novice drivers need to know today, what skills do they need to perfect and how do we test them?“, the foundation stones of CIECA, especially knowledge, skills and testing are more in depth explored. 

NTUA Professor George Yannis has contributed actively at the “Vision Zero for the Balkans” Road Safety Conference organized by IRF in Belgrade, Serbia, on 15 May 2023, with the presentation titled “Network Wide Road Safety Assessments to diagnose road safety risk”. Some of the key issues of this conference are to promote  the uptake of “Vision Zero” policies and make a compelling case for safety investment, focus on risk factors and road deficiencies that lead to injuries among vulnerable road users and advance regional cooperation.  NTUA actively contributed with the following presentation:

• Network Wide Road Safety Assessments to diagnose road safety risk

The Horizon 2020 research project SHOW (SHared automation Operating models for Worldwide adoption) has recently released the SHOW 7th Newsletter. The Newsletter provides information on the latest outcomes of the project. The sites had the opportunity to present their achievements in a recent Review Meeting with the European Commission, where  the excellent work being done across the project, the results that are beginning to emerge, and of course, the challenges to overcome to allow the sites to fulfill their potential, were discussed. SHOW’s aim now is to enhance urban mobility and automation by understanding people’s needs. 

A paper titled “Comparing Machine Learning Techniques for Predictions of Motorway Segment Crash Risk Level” authored by Dimitris Nikolaou, Apostolos Ziakopoulos, Anastasios Dragomanovits, Julia Roussou and George Yannis has been published in Safety. The techniques considered were Logistic Regression, Decision Tree, Random Forest, Support Vector Machine, and K-Nearest Neighbours. Among the five techniques, the Random Forest model achieved the best classification performance (overall accuracy: 89.3%). The findings of this study are particularly useful as the Random Forest model could be used as a highly promising proactive road safety tool for identifying potentially hazardous motorway segments. 

The Horizon 2020 research project PHOEBE has recently released the PHOEBE 1st Newsletter, which provides information on the latest outcomes of the EU-funded ‘Predictive Approaches for Safer Urban Environment’ (PHOEBE) project aiming to increase the road safety of vulnerable road users, especially those who use active mobility and e-scooters. Special focus is given to the assessment of current transport pilot plans in Athens, carried out by NTUA. 

The World Road Association – PIARC recently published a Report titled “The Use of Big Data for Road Condition Monitoring“. This work provides an overview of numerous big data sources and the data-processing methods that can be used to analyse data for road condition monitoring. It focuses on solutions that allow data to be collected quickly, in real time and repeatedly. Also included is a summary of several completed or ongoing projects that have utilised many of the big data sources described in this document.  

The World Health Oganisation (WHO) in collaboration with the Global Alliance of NGOs for Road Safety recently developed a guide that clearly defines the role that nongovernmental organizations can have in advocating on behalf of people who need emergency care, including those injured in road traffic crashes.  This guide is especially targeted towards nongovernmental organizations that operate with limited resources. While those affected by injuries and other health emergencies have a range of physical, psychological and legal needs, this publication is focused on advocacy for the time-sensitive health care that can save millions of lives every year.

The Public Policy Guide for Cycling has released the Ministry of Infrastructure and Transport, which includes a plan for the promotion of cycling in Greece in the horizon of 2030. The Deputy Minister of Infrastructure and Transport, responsible for transport issues, Michalis Papadopoulos pointed out the importance of promoting the use of bicycles as an equal mean of transport for all citizens. The objective to increase the share of travel by bicycle requires the cooperation of all stakeholders, institutional and non-institutional.  

A paper titled “Analysis of mobile phone use engagement during naturalistic driving through explainable imbalanced machine learning” authored by Apostolos Ziakopoulos, Armira Kontaxi and George Yannis has been published in Accident Analysis and Prevention. Results indicate that the decision of drivers to use a mobile phone while driving is governed by a number of complex, non-linear relationships. Total trip distance is the most significant predictor variable by a wide margin, with mean SHAP values of 0.79 towards affecting the model decisions for the probability of mobile phone use of each driver. Fuel consumption had a particularly strong non-linear effect, as higher values of this variable lead to both higher and lower probability of drivers using a mobile phone, deviating from the safer average.  

The European Commission adopted a Recommendation designed to help Member States support their towns and cities in cutting transport emissions and improving urban mobility. The Commission recommends putting in place national programmes to support urban mobility planning and implementation, managed by a dedicated office. Support for cities should include guidance materials, training programmes and capacity building, as well as technical expertise and financial support. Peer learning and networking between cities and towns will be encouraged through the sharing of good practices and that will lead to reinforcement of road safety.

A paper titled “Exploiting Surrogate Safety Measures and Road Design Characteristics towards Crash Investigations in Motorway Segments” authored by Dimitris Nikolaou, Apostolos Ziakopoulos, Katerina Deliali, Yannis Handanos, Christos Karadimas, Giorgos Kostoulas, Elina Frantzola and George Yannis has been published in Infrastructures. For this analysis, a database containing data on injury and property-damage-only crashes, road design characteristics, and SSMs of 668 segments was compiled and utilized. The results of the developed negative binomial regression model revealed that crash frequency is positively correlated with the average annual daily traffic volume, the length of the segment, harsh accelerations, and harsh braking. 

A paper titled “Pedestrian safety attitudes and self-declared behaviour in Greece” authored by Dimitris Nikolaou, Alexandros Ntontis, Eva Michelaraki, Apostolos Ziakopoulos and George Yannis has been published in IATSS Research. The two selected dependent variables for modelling are (i) crossing the road at places other than at a nearby (distance less than 30 m) designated pedestrian crossing and (ii) crossing the road when a pedestrian light is red. Several statistical relationships were discovered correlating these unsafe self-declared behaviours with numerous explanatory variables. From the Structural Equation Models, a positive statistically significant covariance of the two dependent variables was discovered, revealing that a pedestrian who will engage more frequently in crossing the road with red pedestrian light is more likely to also engage in crossing the road at places other than at a nearby pedestrian crossing. 

A paper titled “Impacts of autonomous on-demand mobility service: A simulation experiment in the City of Athens” authored by Vasileios Mourtakos, Maria Oikonomou, Pantelis Kopelias, Eleni Vlahogianni and George Yannis has been published in Transportation Letters.  To that end, an urban on-demand shuttle service was designed, optimized, based on a variation of the Dial-a-Ride optimization problem (DARP), and implemented in the road network of the city of Athens to serve different portions of demand with various capacity specifications. Findings show that it led to improved network level traffic conditions, as delays decreased, and that traffic impacts evolve with fleet capacity and served demand. Furthermore, the number of conflicts decreased and the environmental conditions significantly improved, with CAVs in the network, while the traveled distance increased. 

The World Health Organization has released a Road Safety Manual for decision-makers and practitioners concerning Powered two- and three-wheeler Safety. Key risk factors for motorcycle traffic injuries include the non-use of helmets, vehicle speed, alcohol use, mixed traffic conditions, a lack of protection from the vehicle in a crash and a lack of safe infrastructure for PTWs such as poor road surfaces and roadside hazards. This second edition of the Powered two- and three- wheeler Safety Manual includes guidelines for implementing, enforcing and evaluating 2-and-3-wheeler safety programmes.  

The World Health Organization has released a Road Safety Manual for decision-makers and practitioners concerning Occupant Restraints. The purpose of the second edition of this manual is to provide evidence, advice and examples that will lead to increased use of occupant restraints as safety devices at the national level. Rooted in new case studies and evidence, including from low- and middle-income countries, it includes recommendations for developing and implementing technical standards and legislation, advice on monitoring and evaluating progress, and suggestions regarding other multidisciplinary measures.   

The International Commission for Driver Testing (CIECA) organised with great success the 54th CIECA Congress, which was held in Naples, on 8-9 June 2022. With this congress, titled “Driver training and testing: finding the balance between mobility and safety through the use of innovative technology, improved curricula and data analysis”, CIECA focused on how advancing the importance of driver training and testing can help reducing the number of people killed and seriously injured on roads every year. 

A paper titled “Autonomous Vehicles in Urban Networks: A simulation-based Assessment” authored by Athina Tympakianaki, Leyre Nogues, Jordi Casas, Mark Brackstone, Maria Oikonomou, Eleni Vlahogianni, Tamara Djukic and George Yannis has been published in Transportation Research Record. A combination of microscopic and macroscopic simulations as well as statistical methods are applied. The results indicate a positive impact in relation to capacity changes resulting from the presence of Autonomous Vehicles (AVs) which vary with penetration rate. Analysis of three different urban networks, Barcelona, Bilbao (Spain), and Athens (Greece), reveals consistent trends.  

A paper titled “Humanizing Autonomous Vehicle Driving: Understanding, Modelling and Impact Assessment” authored by Foteini Orfanou, Eleni Vlahogianni, George Yannis and Evangelos Mitsakis has been published in Transportation Research Part F: Traffic Psychology and Behaviour. The proposed framework consists of four sequential steps: i. conceptual design, ii. data collection, processing and mining, iii. modelling and iv. autonomous vehicles impact assessment. The connection between these steps is illustrated and various Key Performance Indicators (KPIs) are specified for each impact area. The paper ends with highlighting some conceptual and modeling challenges that may critically affect the study of acceptance of autonomous vehicles in future mobility scenarios. 

A paper titled “Classification and Evaluation of Driving Behaviour Safety Levels: A Driving Simulation Study”  authored by Kui Yang, Costantinos Antoniou and George Yannis has been published in IEEE. The proposed methodology focuses on determining the optimal aggregation time interval, finding the optimal number of safety levels for driving behavior, classifying the safety levels, and evaluating the driving safety levels in real time. Support vector machines, decision trees and naïve Bayes classifiers were then developed as classification models. The accuracy of the combination of k-means clustering and decision trees proved to be the best with three clusters.  

ERTICO,  ITS Asia-Pasific and ITS America co-organised the 27th ITS World Congress which was held in Hamburg, on 11-15 October 2021, under the theme: “Experience Future Mobility Now”. ITS World Congress is the forum to make meaningful connections, experience inventive conference program presented by industry experts, and see cutting-edge technology in the Exhibit Hall. ITS World Congress allows the smart mobility community to come together to explore the deployment of intelligent transportation technologies that saves lives, improves mobility, promotes sustainability, and increases efficiency and productivity.​ 

Apostolos Ziakopoulos, Dimitris Nikolaou, Armira Kontaxi, Eva Michelaraki, Virginia Petraki, Maria G. Oikonomou and  Marios Sekadakis, Research Associates of the Department of Transportation Planning and Engineering of NTUA were awarded with the NTUA Thomaidion Award for outstanding road safety publications in scientific journals. The awards for publications in Scientific Journals concerned:

• Ziakopoulos A., Yannis G., IA review of spatial approaches in road safety. Accident Analysis & Prevention, 135, 105323. (2020) 
• Yannis G., Nikolaou D., Laiou A., Achermann Stürmer Y., Buttler I., Jankowska-Karpa D., Vulnerable road users: Cross-cultural perspectives on performance and attitudes, IATSS Research, Vol.44, Issue 3, 2020, pp. 220-229. 
• Ziakopoulos A., Tselentis D., Kontaxi A., Yannis G. A critical overview of driver recording tools, Journal of Safety Research. 
• Katrakazas C., Michelaraki E., Sekadakis M., Yannis G., A descriptive analysis of the effect of the COVID-19 pandemic on driving behavior and road safety, Transportation Research Interdisciplinary Perspectives, Vol. 7, 2020. 
• Petraki V., Ziakopoulos Z., Yannis G., Combined impact of road and traffic characteristic on driver behavior using smartphone sensor data, Accident Analysis & Prevention,  Vol. 144, 2020. 
• Oikonomou M., Orfanou F., Vlahogianni E., Yannis G., Impacts of Autonomous Shuttle Services on Traffic, Safety and Environment for Future Mobility Scenarios,  IEEE Xplore, 2020, pp. 1-6. 
• Katrakazas C., Michelaraki E., Sekadakis M., Yannis G., A descriptive analysis of the effect of the COVID-19 pandemic on driving behavior and road safety, Transportation research interdisciplinary perspectives, 7, 100186. 

The World Bank Global Road Safety Facility (GRSF) has published a Report titled “The High Toll of Traffic Injuries: Unacceptable and Preventable”. It proposes a comprehensive methodology to quantify both the income growth and social welfare benefits that safer roads could bring to developing countries.  The study shows that reducing the number of RTIs in developing countries not only increases income growth, but also generates substantial welfare benefits to societies.