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As part of the European Horizon 2020 project i-DREAMS**, a medium-fidelity driving simulator study was conducted to evaluate safety effects of a new advanced driver-assistance system (ADAS) on cyclists overtaking by cars. The proposed ADAS was designed with a multimodal human-machine interface, auditory as well as visual information, using a multistage warning system, alerting drivers well in advance about the potential danger so that an imminent collision with the cyclist may be avoided due to attentive drivers. The warning strategy is based on a combination of lateral clearance and time-to-danger parameters. Forty-eight drivers drove the two-lane rural highway experimental route twice, without and with the ADAS, in three different car-to-cyclist overtaking scenarios. Statistical tests were performed to evaluate the effects of drivers’ gender and age on the effectiveness of the ADAS system. Overall, the study results show that the proposed in-vehicle driving assistance system had a significant effect in increasing the lateral clearance and in reducing the aerodynamics forces that can destabilize the cyclist overtaken by car. The ADAS system was more effective for female and older drivers. Finally, the implementation in real word of the proposed driving aid system will have positive impacts on cyclist safety and comfort, making the car-to-cyclist overtaking less dangerous. This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 814761.

Safety reviews of existing roads are becoming an accepted practice in many agencies around the world. These reviews can be highly cost-effective, but the subjective nature of the process can give rise to inconsistencies that limit their effectiveness. To address this issue, a technique to support safety reviews to quantify the safety gains that could be achieved by addressing the problems identified in the review process is presented. The approach is based on known accident relationships. A systematic process to determine which road features should be investigated and how each feature should be evaluated during the review is described. The procedure addresses rural two-lane highways at nonintersections. From the process, a potential for a safety improvement index (PFI) was calculated. Validation of the procedure was carried out by a comparison of the PFI values with the expected collision frequency. PFI was assessed in 406 km of rural two-lane rolling highways in Italy. Collision frequency was determined by application of a collision prediction model, calibrated in the study network, and was refined by application of the empirical Bayes (EB) technique. Correlation between EB safety estimates and PFI values is highly significant, with 93% of the variation in the estimated number of accidents explained by the PFI value. Because of the validation and quantitative nature of the PFI, the procedure can be used to support safety reviews and decision making.

Road Safety Inspections (RSI) are recognised as an effective tool for identifying safety issues. However, due to the subjective nature of the process, they may give rise to disagreements which limit their effectiveness. In the framework of the IASP research program sponsored by European Commission, which is focused on rural two-lane highways, a RSI procedure aimed at improving the effectiveness and the reliability of the methodology has been defined. For this purpose, the research has been pinpointed on the inspection framework, on the inspectors and client roles and, with special emphasis, on the methodologies used for identifying and ranking the safety problems. In order to test the reliability of the methodology, the agreement of the results of the safety issues ranks produced by different inspectors has been addressed. Specifically, the statistic kappa has been used. Results show that there is a statistically significant level of agreement among inspectors for the majority of safety issues. The reliability of the procedure is satisfactory, especially if it is considered that the identification of the safety issues is a very complex task based on human evaluations and expertise not supported by instrumental measures. Automobilių kelių apžiūra saugaus eismo požiūriu (RSI) yra pripažinta efektyvi priemonė saugaus eismo problemoms nustatyti. Tačiau, dėl savo subjektyvaus pobūdžio, apžiūra gali tapti pagrindu nesutarimams, kurie apriboja apžiūros efektyvumą. IASP tyrimų programoje, kurią finansiškai remia Europos Komisija ir kurioje analizuojami dviejų eismo juostų užmiesčio keliai, pateikta RSI procedūra, numatyta apžiūrų metodologijos efektyvumui ir patikimumui tobulinti. Tuo tikslu tyrimų tikslu tapo apžiūrų struktūra, inspektoriaus ir užsakovo pareigos, ypatingai akcentuojant saugaus eismo problemų nustatymo ir klasifikavimo metodologiją. Norint patikrinti metodologijos patikimumą ypatingas dėmesys skirtas susitarimui dėl saugaus eismo problemų klasifikavimo rezultatų, pateikiamų atskirų inspektorių. Konkrečiai, panaudota statistinė kapa. Rezultatai rodo, kad susitarimo lygis tarp inspektorių dėl daugumos saugaus eismo problemų yra statistiškai svarbus. Procedūros patikimumas yra patenkinamas, ypač turint galvoje, kad saugaus eismo problemų nustatymas yra labai sudėtinga užduotis, pagrįsta žmogaus vertinimais ir patirtimi, be jokių instrumentinių priemonių pagalbos. Ceļa drošības inspekcija (RSI) ir zināma kā efektīvs līdzeklis drošības pasākumu identifikācijai. Kaut arī procesa subjektīvās dabas dēļ tie var izraisīt nesaskaņas, kas ierobežo piedāvāto pasākumu efektivitāti. IASP pētniecības programmas ietvaros, kuru sponsorē Eiropas Komisija, un kas ir koncentrēta uz divu joslu automaģistrālēm, tiek definēta metode, kuras mērķis ir uzlabot RSI procedūru efektivitāti un drošumu. Tādēļ pētījums ir sašaurināts līdz inspekcijas ietvaram, inspektora un klienta lomai un, ar speciālu akcentu, metodēm, kas tiek lietotas drošības problēmu identifikācijai un klasifikācijai. Lai pārbaudītu metodes drošumu tiek analizēts dažādu inspektoru noteiktais drošības līmenis. Tiek pielietots īpašais statiskais koeficients kapa. Iegūtie rezultāti rāda, ka lielākajā daļā gadījumu ir redzama laba saskaņa starp dažādu inspektoru veiktajiem drošības līmeņa novērtējumiem. Piedāvātās procedūras drošums ir apmierinošs, īpaši, ņemot vērā to, ka drošības jautājumu identifikācija ir ļoti komplekss uzdevums, kas balstās uz cilvēces attīstību un pieredzi un netiek balstīts uz instrumentāliem mērījumiem. Teede liiklusohutusaudit on efektiivne vahend ohutusprobleemide identifitseerimiseks. Kuid oma subjektiivse iseloomu tõttu võivad auditi tulemused põhjustada erimeelsusi, mis vähendavad nende efektiivsust. Euroopa Komisjoni rahastatud IASP uurimisprogrammi raames, mis käsitleb kaherealisi maanteid, nähti ette teede liiklusohutuse auditeerimise metoodika efektiivsuse ja usaldusväärsuse tõstmine. Seetõttu on uurimistöö suunatud auditeerimise põhialustele, audiitori ja tellija rollile ja erilise rõhuga ohutusprobleemide identifitseerimise ja klassifitseerimise metoodikatele. Metoodika usaldusväärsuse kontrolliks kasutati erinevate audiitorite teostatud ohutusprobleemide klassifitseerimistulemuste võrdlust. Selleks kasutati statistilist väärtust kappa. Võrdlustulemused näitavad, et erinevate audiitorite poolt teostatud ohutusprobleemide hindamistulemuste vahel esineb statistiliselt tugev seos. Metoodika usaldusväärsus on rahuldav arvestades, et ohutusprobleemide väljaselgitamine on väga keerukas ülesanne, mis põhineb vaid subjektiivsel hindamisel ja audiitori kogemusel, mõõteseadet kasutamata.

This study evaluated the effectiveness of speed limits enforced with an automated section speed enforcement system (ASSES) through the analysis of compliance after the system implementation in the Italian Motorway A3 Naples-Salerno. The speed limits were selected taking into account the average of the following values: (1) minimum design speed; (2) minimum speed consistent with the available stopping sight distance; and (3) operating speeds before the ASSES implementation. The first two criteria take into account safety whereas the third criterion takes into account the mobility needs. The speed limits selected with these criteria were then refined basing on: maximum difference between the section speed limit and the minimum speed evaluated with criteria 1 and 2, evaluation of critical conditions, and consistency between the speed limits and the highway function. The system was activated on April 21, 2010 and the driving speeds were monitored in the two periods April 21, 2010 - May 11, 2010 and March 30, 2011 - April 20, 2011. Overall, non compliance to the speed limits was equal to 50%. Non compliance was higher for heavy vehicles (60-70%) than for light vehicles (32-65%). Non compliance of light vehicles was much higher in the sections with the most constrained alignments (64% in sections with speed limit equal to 80 kph vs. 34% in sections with speed limit equal to 100 kph). Higher compliance to the speed limits, according to the authors’ belief, might be achieved by a better strategy of communication and information to the road users and a speed limit management strategy synergic between the highway agency and the Police who actually manages the commitments of fines., JRC.F.8-Sustainable Transport

In this study, a methodology for the selection of speed limits in sections enforced with automated section speed enforcement systems (ASSESs) has been proposed. Results of the speed control system have been assessed by speed monitoring after the system implementation in the Italian Motorway A3 Naples-Salerno. The speed limits were selected taking into account the average of the following values: (1) minimum design speed; (2) minimum speed consistent with the available stopping sight distance; and (3) operating speeds before the ASSES implementation. The first two criteria take into account safety whereas the third criterion takes into account the mobility needs. The speed limits selected with these criteria were then refined basing on: maximum difference between the section speed limit and the minimum speed evaluated with criteria 1 and 2, evaluation of critical conditions, and consistency between the speed limits and the highway function. Overall, non compliance to the speed limits was equal to 50%. Non compliance was higher for heavy vehicles (60-70%) than for light vehicles (32-65%). Non compliance of light vehicles was much higher in the sections with the most constrained alignments (64% in sections with speed limit equal to 80 kph vs. 34% in sections with speed limit equal to 100 kph). Higher compliance to the speed limits, according to the authors’ belief, might be achieved by a better strategy of communication and information to the road users and a speed limit management strategy synergic between the highway agency and the Police.

Le intersezioni costituiscono solo una piccola parte del-l’intero sistema stradale, ma è nelle intersezioni che si verificano la maggior parte degli incidenti: oltre il 50% del totale nelle aree urbane e oltre il 30% nelle aree extraur-bane. La maggior parte degli incidenti è causata da errori uma-ni che i guidatori compiono a causa delle limitazioni fisiche, per-cettive e cognitive proprie degli esseri umani. Spesso i guidatori non percepiscono in tempo l’intersezione approcciando ad essa con velocità elevata e, come ben noto, con l’incremento della velocità aumenta la probabilità di commettere un errore e di-minuisce il tempo disponibile per effettuare azioni correttive. Inoltre, all’aumentare della velocità aumenta la gravità degli in-cidenti. Al fine di ridurre l’incidentalità nelle intersezioni ex-traurbane caratterizzate da elevate velocità operative sono state progettate delle misure percettive di basso costo, ossia misure finalizzate a modificare la percezione dell’ambiente stradale da parte dei guidatori senza cambiare la configura-zione fisica della strada. La valutazione di efficacia delle dif-ferenti alternative di intervento è stata condotta attraverso una sperimentazione con il simulatore di guida ad alta fedel-tà VERA (Virtual Enviromnent for Road sAfety) di TEST Scarl (Technology for Trasportation, Environment and Safety).