Exploring injury severity of children and adolescents involved in traffic crashes in Greece

For the purpose of exploring the factors affecting injury severity of children and adolescents involved in traffic crashes in Greece,disaggregate crash data including 13,431 involving children and adolescents from all regions of Greece for the period 2006–2015 were utilized.In order to identify factors affecting injury severity and account for potential unobserved heterogeneity,a series of mixed logit models were utilized.To explore and address potential temporal instability of crash-related risk factors,the likelihood ratio test was applied.Results indicated that night crashes,crashes outside urban areas as well as crashes involving bicycles or powered-two-wheelers are associated with higher injury severity of children and adolescents.Interestingly,crashes involving pedestrians are associated with lower injury severity than head-on collisions and run-off-road collisions with fixed objects.Side and sideswipe crashes also result in lower injury severities.The likelihood ratio test indicated that crash-related factors are instable when comparing the models utilizing data before and after 2010 respectively.This study contributes to the current knowledge in the field,as to the best of our knowledge this is the first study that addresses unobserved heterogeneity when analyzing child and adolescent injury severity.Overall,the findings of this study provide useful insights and could assist in unveiling crash risk factors and prioritize programs and measures to promote road safety of children and adolescents.

Autonomous vehicles wheel wander: Structural impact on flexible pavements

Autonomous vehicles(AVs), including trucks, are already available and their adoption is coming at a rapid pace. Despite the fact that this new transportation technology will travel on existing pavement infrastructure assets, the study and investigation of the AVs structural impact on pavements has not reached the same level of attention and maturity as other related research areas. Considering the extensive investment on pavement construction and maintenance, the necessity to fully understand these impacts in the long term, is becoming evident. The present paper presents and discusses currently published relevant research and findings on the quantification of the wheel wander potential impact,both negative and positive, offering potential insightful future areas of enquiry to help mold and shape future research for this emerging field. The paper focuses on the impact of the AVs zero lateral wheel wander on both new flexible pavement design and the damage accumulation within existing flexible pavement structures. Other wheel wander distributions(normal, uniform, etc.) are investigated as well. The outcome and findings are that the AVs zero lateral wheel wander has a definable negative structural impact on flexible pavement structures in comparison to current human-driven(non-autonomous) vehicles that tend to follow a normal lateral wheel wander distribution. However, under certain defined conditions(optimal wheel wander distribution), the pavement service life can be potentially extended.

State-of-the-art review on multi-criteria decision-making in the transport sector

Consistent decision-making requires a structured and systematic evaluation of advantages and disadvantages of different choice possibilities.For transport projects,policies or policy measures,and transport options evaluation,various multi-criteria methods have been developed and effectively applied to complement conventional cost effectiveness and cost benefit analysis.The present paper aims to present a state-of-the-art review of pertinent literature regarding multi-criteria decision-making(MCD M)in the transport sector,focusing on the basic concepts and procedure for multi-criteria decision-making in the transport sector,along with its role and evaluation parameters.A large selection of over 50 papers and publications between 1982 and 2019 have been reviewed,in order to provide an insight into the uses of MCDM methods in transport applications.Most commonly used MCDM metho ds techniques are identified and discussed through a wide review of pertinent literature,research and case studies,leading to interesting conclusions that provide a valuable insight into the use of multicriteria analysis techniques in transport sector related decision-making.Based on the wide range of reviewed literature,it is concluded that MCDM methods are being applied mostly to evaluate transport options rather than transport policies or projects and the most commonly used MCDM method in transport sector problems are analytic hierarchy process(AHP).

Exploring speeding behavior using naturalistic car driving data from smartphones

The present research aimed to identify critical factors that affect speeding behavior.For that purpose,high-resolution smartphone data collected from a naturalistic driving experiment of 88 drivers were utilized,augmented with data from self-reported questionnaires.Using risk exposure and driving behavior indicators calculated from smartphone sensor data,as well as demographic characteristics and self-reported driving performance,statistical analysis was carried out for modelling the percentage of driving time over the speed limit,namely by means of generalized linear mixed-effects models.More precisely,an overall model was developed for all road environments,and additional separate models were developed for driving on urban and rural roads.The results from the interpretation of the estimated parameters of the models can be summarized as follows:the parameters of trip distance and mobile phone use while driving have been determined as statistically significant and positively correlated with the percentage of speeding time during a driver's trip.In the same context,male drivers and drivers in the age group of18-34 also increase the percentages of speeding instances while driving.Regarding driving behavior as stated on the questionnaire,it seems that low frequencies of self-declared speeding(never or rarely)are statistically significant and negatively correlated with the percentage of speeding time.It is expected that this research can provide considerable gains to society,since the stakeholders including policy makers and industry could rely on the results and recommendations regarding risk factors that appear to be critical for safe driving.