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Autonomous truck platoons hold the potential for substantial economic and environmental advantages. However, there is a lack of comprehensive research on the interactions between drivers and different configurations of truck platoons at waving segments. This study aims to contribute to the literature by achieving three primary objectives: (1) examine the effects of various truck platoon configurations on merging and diverging behaviors [time to merge (TTM) and time to diverge (TTD)]; (2) explore the impact of individual characteristics such as age, gender, education level, and driving experience on TTM and TTD; and (3) investigate the decision-making associated with these maneuvers (merging or diverging in front of the platoon, behind the platoon or cut in through the platoon). A driving simulator study was conducted with 85 participants across 12 distinct scenarios, considering variations in platoon size, intraplatoon spacing, and platoon lane-change behavior. Several statistical methods were employed, including ANOVA, the Cox proportional hazards model, and machine-learning techniques, to analyze the factors impacting TTM and TTD. The results revealed that increasing the headway distances between trucks in a platoon to 13.72 m (45 ft) or 18.29 m (60 ft) substantially decreased TTM, enhancing traffic flow. Furthermore, splitting the truck platoon between two lanes of the freeway before the merging point significantly influenced other drivers' merging decisions. When half of the trucks in a platoon switched to the left lane before the merging point, a larger proportion of participants chose to merge ahead of the platoon. Age, gender, education level, and self-assessment of driving skills were all found to significantly influence merging and diverging behaviors. Drivers with higher degrees took longer to merge, whereas older, male, and experienced drivers merged faster. The lowest average TTD was observed when half the platoon switched to the left lane before the diverging point. [ABSTRACT FROM AUTHOR]

Lack of visibility is one of the challenges that impact drivers' ability to perform driving tasks at night. Although prior studies indicated that lighting increases nighttime safety, lighting at stop-controlled intersections is not mandatory according to many U.S. states' guidelines. This paper aims to investigate the impact of different lighting conditions on safety-related driving behavior during nighttime at stop-controlled intersections. The data were collected using a driving simulator experiment where participants drove through several intersections during daytime, nighttime without lighting, nighttime with partial lighting, and nighttime with full lighting. Collected measures included speed, time-to-collision (TTC), and post-encroachment time (PET). TTC/PET were used as safety surrogate measures to evaluate the impact of lighting on drivers' safety. The results indicated that TTC/PET were higher during daytime and nighttime with partial/full lighting. Furthermore, the findings revealed that lower speeds were recorded at nighttime with partial/full lighting. Kruskal–Wallis test revealed that TTC/PET medians for nighttime without lighting were statistically significantly different from TTC/PET medians of the remaining lighting conditions. Moreover, negative binomial modeling indicated that lack of lighting and speed had inverse correlation with TTC. In summary, the results revealed that street lighting at stop-controlled intersections provided 37% increase in TTC, 15% increase in PET, and 15% reduction in speed. [ABSTRACT FROM AUTHOR]

Recently, the severity of injuries resulting from traffic crashes has been extensively investigated in numerous studies. However, the number of studies that addressed the severity of the run-off-road (ROR) crashes is relatively low. In the Emirate of Abu Dhabi (AD), approximately 22% of the total serious crashes and fatalities that occurred from 2007 to 2013 were ROR crashes. Despite these facts and the uniqueness of the composition of licensed drivers in AD (approximately 87% of them are non-Emiratis), the factors affecting the occurrence and severity of ROR crashes in AD have not been explicitly addressed in any prior studies. Therefore, this study aims to investigate the characteristics of at-fault drivers involved in ROR crashes in AD, the nature and main causes of those crashes. In this regard, conditional distribution and two-way contingency tables were developed. In addition, this study aims to identify and quantify the factors affecting the severity of ROR crashes such as driver, road, vehicle and environment factors. To achieve this goal, ordered probit model approach was employed. Crash data for a total of 3819 ROR crashes that occurred in AD were employed in the analysis. The results indicated that driver factors (carelessness, speeding, and nationality), vehicle characteristics (vehicle type), and road and environment factors (road type, crash location and road surface condition) were the significant factors influencing the severity of ROR crashes in AD. Countermeasures to improve traffic safety and reduce numbers and severity of ROR crashes in AD were discussed. Key words: run-off-road crashes, crash severity, traffic safety, ordered logit model. La gravite des blessures causees par des accidents de la route a recemment fait l'objet de nombreuses etudes approfondies. Cependant, assez peu d'etudes se sont interessees a la gravite des accidents provoques par une sortie de route (SDR). Dans l'emirat d'Abou Dabi (AD), environ 22 % des accidents graves et mortels denombres entre 2007 et 2013 etaient des accidents causes par une SDR. Malgre cela et en depit de la composition singuliere de la population des conducteurs titulaires d'un permis de conduire dans l'emirat d'AD (environ 87 % d'entre eux n'etant pas des Emiratis), les facteurs qui influent sur le nombre et la gravite des accidents dus a une SDR n'avaient jamais ete serieusement etudies auparavant. Par consequent, la presente etude vise a etudier les caracteristiques des conducteurs de conducteurs responsables impliques dans des accidents provoques par un SDR dans l'emirat d'AD ainsi que la nature et les principales de ces accidents. Pour ce faire, des distributions conditionnelles et des tableaux de contingence a double entree ont ete crees. La presente etude a egalement pour objectif de determiner et de quantifier les facteurs qui influent sur la gravite des accidents causes par une SDR, tels que le conducteur, la route, le vehicule et les facteurs environnementaux. Pour atteindre un tel objectif, une methode sur un modele probit ordonne a ete utilisee. Pour realiser cette etude, on s'est servi des donnees relatives a 3819 accidents causes par une SDR et survenus dans l'emirat d'AD. Les resultats ont montre que les facteurs associes aux conducteurs (manque de vigilance, vitesse de conduite et nationalite), les caracteristiques des vehicules impliques (type de vehicule) et les facteurs environnementaux et lies a la route (type de route, lieu de l'accident et etat de la surface de la route) influaient beaucoup sur la gravite des accidents provoques par une SDR et survenus dans l'emirat d'AD. Des mesures visant a ameliorer la securite routiere et a reduire le nombre et la gravite des accidents dus a une SDR dans l'emirat d'AD sont egalement presentees. [Traduit par la Redaction] Mots-cles: accidents causes par une sortie de route, gravite des accidents, securite routiere, modele logit ordonne., Introduction Run-off-road (ROR) crashes are considered as one of the major causes of fatalities and serious injuries in traffic crashes around the world. Run-off-road crashes occur when the driver loses [...]

The Qatari government introduced a major public transport project titled the Doha Metro system to address the fast growing transportation demands in Qatar's urban areas and to be ready for the Qatar 2022 FIFA World Cup. To benefit from this new metro system in reducing traffic congestion problems in Doha, it must be attractive with a reasonable level of service to attract large numbers of car users to switch to the new metro. This goal can be achieved by a better understanding of the user's needs and expectations in Qatar. This paper aims to identify and quantify the significant factors affecting commuters' perspectives, preferences and tendencies to use this new metro network for their daily trips in the future. The data used for the analysis was obtained from a self-reported questionnaire survey carried out among a sample of commuters living in Doha. Different data mining techniques were employed including conditional distributions and two-way analysis. In addition, logistic regression and structural equation modeling approaches were developed. The results revealed that the location of metro stations, the metro station's features, the metro's features, gender, the number of daily trips, the purpose of trips, and the average duration of trips in Doha were the significant factors that affected commuters' willingness and tendency to use the new metro system. The results of this study provide authorities and decision makers in Doha with valuable insights that should be taken into consideration prior to implementing the new metro service to ensure its success. Key words: public transit, commuters' willingness to use public transit, commuters' satisfaction, service quality, travel mode choice. Resume: Le gouvernement qatari a lance la construction un grand projet de transport en commun, le metro de Doha, pour faire face a la forte croissance de la demande en matiere de transports dans les regions urbaines du Qatar et pour que le pays soit en mesure d'accueillir la Coupe du Monde de la FIFA 2022. Pour etre avantageux et contribuer a reduire les embouteillages a Doha, ce nouveau metro devra offrir un niveau de service acceptable de facon a encourager un grand nombre d'automobilistes a l'emprunter plutot que d'utiliser leur voiture. La realisation d'un tel objectif passera par une meilleure comprehension des besoins et attentes des usagers qataris. Le present article a pour but de determiner et de mesurer les facteurs qui influenceront le plus les intentions, les preferences et les tendances des banlieusards quant a l'utilisation quotidienne de ce nouveau reseau de metro a l'avenir. Les donnees utilisees pour cette analyse proviennent de questionnaires d'enquete auxquels a repondu un echantillon d'habitants de la banlieue de Doha. Diverses techniques d'exploration de donnees ont ete utilisees, dont celle des distributions conditionnelles et l'analyse a deux facteurs. En outre, des modelisations par regression logistique et par equation structurelle ont ete developpees. Les resultats de ces analyses ont montre que l'emplacement des stations de metro, leurs caracteristiques, le sexe des usagers, le nombre de leurs deplacements quotidiens et le but et la duree moyenne des deplacements a Doha constituaient les facteurs qui influenceraient le plus les choix et les tendances des banlieusards quant a l'utilisation de ce nouveau reseau de metro. Les resultats de la presente etude fournissent aux autorites et aux decideurs des donnees precieuses qui devront etre prises en compte avant la mise en service du nouveau metro afin d'en assurer le succes. [Traduit par le Redaction] Mots-cles : transports en commun, volonte des banlieusards d'utiliser les transports en commun, satisfaction des banlieusards, qualite de service, choix du mode de transport., Introduction The increased rate of car use, especially in rich developing countries, has major implications in terms of pollution, noise, and congestion problems. Commuters are relying more on private cars [...]