Filename
stringlengths 17
17
| Abstract
stringlengths 76
3.38k
| Highlights
stringlengths 80
1.73k
|
|---|---|---|
S0001457519311005 | This paper investigates truck involved crashes to determine the statistically significant factors that contribute to injury severity under different weather conditions . The analysis uses crash data from the state of Ohio between 2011 and 2015 available from the Highway Safety Information System . To determine if weather conditions should be considered separately for truck safety analyses parameter transferability tests are conducted the results suggest that weather conditions should be modeled separately with a high level of statistical confidence . To this end three separate mixed logit models are estimated for three different weather conditions normal rain and snow . The estimated models identify a variety of statistically significant factors influencing the injury severity . Different weather conditions are found to have different contributing effects on injury severity in truck involved crashes . Rural rear end and sideswipe crash parameters were found to have significantly different levels of impact on injury severity . Based on the findings of this study several countermeasures are suggested 1 safety and enforcement programs should focus on female truck drivers 2 a variable speed limit sign should be used to lower speeds of trucks during rainy condition and 3 trucks should be restricted or prohibited on non interstates during rainy and snowy conditions . These countermeasures could reduce the number and severity of truck involved crashes under different weather conditions . | Truck driver injury severity is analyzed for three weather conditions. Parameter transferability tests suggest that separate models should be used. Mixed logit models are estimated to identify significant contributing factors. A good number of contributing factors are uniquely associated to weather condition. |
S0001457519311029 | Methods based on crash data analysis are effective in identifying intersections with a potential for safety improvement . However it is well recognized that crash data suffer from several shortcomings and that there are clues to safety other than crash occurrence . The systemic approach is an alternative method to address safety issues . In this approach a transportation agency is able to identify priority locations based on the presence of risk factors rather than actual crashes . To promote wider use of the systemic safety approach this paper aims at developing and validating a procedure to rank unsignalised urban intersections for safety improvement based on the evaluation of risk factors by road safety inspections . | This study developed a procedure to rank unsignalised urban intersections for safety improvement. The procedure identifies and ranks risk factors by safety inspections. The procedure assesses a Safety Index SI for vehicles and pedestrians. The procedure was validated in a sample of eighty nine urban intersections in Florida. The correlation between the SI scores and the Empirical Bayes estimates was significant. |
S0001457519311066 | Skateboarding is being an emerging travel model especially for young travelers . The conflict between skateboarders and the other road users has raised safety concerns for traffic engineers . Safety evaluation about skateboarder related conflicts has not been well performed due to the low skateboarder related crashes and the limited historical crash data . Near crashes have been considered as surrogate data for skateboard related safety evaluation . This paper developed a procedure to extract skateboarder associated near crashes automatically with the roadside Light Detection and Ranging . A new indicator distance deceleration time profile which combined time space and deceleration information was introduced for skateboarder pedestrian near crash identification . The DDTP was developed for the roadside LiDAR data specially . The case studies showed that the proposed method can extract skateboarder pedestrian safety critical events with high accuracy . The proposed method can be also used for skateboarder vehicle and skateboarder bicycle near crash identification . | LiDAR was used for skateboarder related conflicts identification. A new indicator DDTP was introduced for skateboarder pedestrian near crash identification. The developed procedure was evaluated using the real world data. |
S0001457519311108 | Real time crash risk prediction is expected to play a crucial role in preventing traffic accidents . However most existing studies only focus on freeways rather than urban arterials . This paper proposes a real time crash risk prediction model on arterials using a long short term memory convolutional neural network . This model can explicitly learn from the various features such as traffic flow characteristics signal timing and weather conditions . Specifically LSTM captures the long term dependency while CNN extracts the time invariant features . The synthetic minority over sampling technique is used for resampling the training dataset . Five common models are developed to compare the results with the proposed model such as the XGBoost Bayesian Logistics Regression LSTM etc . Experiments suggest that the proposed model outperforms others in terms of Area Under the Curve value sensitivity and false alarm rate . The findings of this paper indicate the promising performance of using LSTM CNN to predict real time crash risk on arterials . | A LSTM Convolutional Neural Network LSTM CNN network is proposed to predict crash risk in real time on arterials. The possibilities of using various data sources for real time crash prediction are explored. Such as Bluetooth data detector data and weather data. One years data are analyzed extensively. Different data preparation techniques are used. Synthetic minority over sampling technique SMOTE is utilized for re sampling the extremely imbalanced crash dataset. The performance of LSTM CNN is compared with other common approaches on the same dataset. Results suggest that the LSTM CNN outperforms the others with various evaluation metrics i.e. Area Under the Curve AUC sensitivity and false alarm rate. |
S0001457519311133 | In this paper we examine the relationship between traffic enforcement and traffic outcomes to identify an optimal point of traffic enforcement . | Stronger association between breath tests and crashes than earlier estimates. Breath tests are subject to calculable marginal returns. The optimal ratio of breath tests per driver estimated to be 1.451.54. |
S0001457519311315 | Although mortality trends can be influenced by different ages periods and cohorts few studies have demonstrated the age period cohort effect on road traffic injury mortality . Moreover APC effects in Korea have never been documented despite the high mortality rates from RTIs . This study aimed to describe the trends in mortality from RTIs and examine APC effects on RTI mortality in Korea . Using the national death certificate and census mid year population estimates data during 19832017 trends in age standardized mortality rates from RTIs were analyzed using Joinpoint regression . Intrinsic estimator regression models were used to estimate APC effects on RTI mortality . Consistent with the trend in period effects RTI mortality increased sharply with the economic growth in the 1980s decelerated after the implementation of road safety policies in the early 1990s plummeted owing to the 19971998 financial crisis and gradually decreased from the early 2000s . A J shaped age effect indicated that the relative risk of road traffic death surged in people aged 65 years . Educational expansion from the mid 1950s turned an increasing birth cohort effect into a continuously decreasing trend after peaking around the 19381943 birth cohorts . The risk of road traffic death was relatively high among the Korean Generation Y i.e . those born in 19781983 . RTI mortality trends in Korea have been affected by diverse socioeconomic changes through cohort and period effects . Despite the recent favorable trend RTI mortality remains high especially among older people . Road safety policies to address the burden of RTIs require further improvement . | Road traffic injury mortality in Korea has declined after peaking in the mid 1990s. Road safety policies and the financial crisis might have affected this decline. Educational expansion might reduce mortality risk through the cohort effect. Mortality risk was high among the Korean Generation Y born in 19781983. Policies to address the burden of road traffic injury require further improvement. |
S0001457519311467 | Speeding has been a great concern around the world due to the occurrence and severity of road crashes . This paper presents an evaluation of the effectiveness of different penalty and camera based enforcement strategies in curbing speeding offences by professional drivers in Hong Kong . A stated preference survey approach is employed to measure the association between penalty and enforcement strategies and drivers speed choices . Data suggest that almost all drivers comply with speed limits when they reach a camera housing section of the road . For other road sections a panel mixed logit model is estimated and applied to understand the effectiveness of penalties and enforcement strategies on drivers speeding behaviors . Driving offence points are found to be more effective than monetary fines in deterring speeding offences albeit there is significant heterogeneity in how drivers respond to these strategies . Warning drivers of an upcoming camera based enforcement section increased speed compliance . Several demographic and employment characteristics driving history and perception variables also influence drivers choices of speed compliance . Finally besides penalty and enforcement strategies driver education and training programs aimed at addressing aggressiveness risk taking traits might help reduce repeated speeding offences among drivers . | This study employed a stated preference approach to evaluate the deterrent effects of penalty and enforcement strategies on the speeding behaviors of professional drivers. Driving offence points are found to be more effective than monetary fines in deterring speeding offences. Warning drivers of an upcoming camera enforcement section increased speed compliance. Demographic and employment characteristics driving history and perception also influence the efficacy of speed compliance strategies. |
S0001457519311510 | The propensity score matching method has been used to estimate safety countermeasure effects from observational crash data . Within the counterfactual framework propensity score matching is used to balance the covariates between treatment and control groups . Recent studies in traffic safety research have demonstrated the strength of this method in reducing the bias caused by treatment site selection . However several general issues associated with safety effect estimates may still influence the effectiveness and robustness of this method . In the present study Bayesian methods were integrated into the propensity score matching method . Bayesian models are known for their ability to capture heterogeneity and modeling uncertainty . This may help mitigate unobserved variable effects in the roadway and crash data . Furthermore the sampling based algorithm used for Bayesian estimation yields more consistent estimates in small region analysis than estimates from frequentist modeling . In this study a dataset that was used to evaluate the safety effects of the dual application of shoulder and centerline rumble strips on two lane rural highways was acquired . Only data from the before treatment period were used in a no treatment effect analysis in order to compare the results of a Bayesian propensity score analysis to a frequentist propensity score analysis . Because no treatment was applied during the analysis period it was assumed that there would be no treatment effect or a crash modification factor equal to 1.0 . The Bayesian propensity score matching method nominally outperformed the frequentist propensity score matching method in the largest sample and produced near identical results in the medium sample but neither method closely approximated the assumed true crash modification factor in the small sample analysis . A simulation study is recommended to further study the effects of sample size and confounding factors when comparing the Bayesian and frequentist propensity score matching methods . | A Bayesian propensity score analysis is compared to a frequentist propensity score analysis. A no treatment study design using observational data was used for the comparison. The Bayesian nominally outperformed the frequentist method in the largest sample. The methods produced near identical results in the medium sample. Neither method closely approximated assumed true safety effect using small sample. |
S0001457519311637 | Faced with the current growth and change to Western Australias road network as well as the promotion and increased uptake of cycling further investigation into crash injury and road infrastructure characteristics is necessary . An in depth study was conducted of 100 cyclists who were injured due to involvement in a crash that occurred on road and resulted in an admission to a hospital . Information collected included a researcher administered questionnaire crash details from the Integrated Road Information System injury information from the State Trauma Registry and a virtual on line site inspection . Overall 42 of crashes involved a motor vehicle and 58 did not involve a motor vehicle . Twenty one percent of all crashes involved cyclist loss of control 18 were crashes with another cyclist 18 involved hitting an object and 1 involved a pedestrian . . Bicycle crashes were severely under reported with only 40 percent reported to the Police . Approximately half of crashes occurred at intersections and half at midblock sites . Fifty seven percent of crashes that occurred at intersections involved a motor vehicle whereas only 27 of crashes that occurred at midblocks involved a motor vehicle . The majority of cyclists injuries were classified as minor according to the Injury Severity Score with the mean number of body regions injured being 4.5 . The mean number of days in hospital care was 5.2 days . These findings can be used to guide road infrastructure treatments that reduce the risk of bicycle crashes in Western Australia and insights may inform action in other jurisdictions where cycling is increasing in popularity . | In depth study of 100 cyclists injured due to an on road crash resulting in hospitalisation. 42 of bicycle crashes involved a motor vehicle and 58 did not involve a motor vehicle. 21 of all crashes involved the cyclist losing control and 18 involved hitting an object. Approximately half of crashes occurred at intersections 51 and half at midblocks non intersections 49 . Road surface maintenance and removal of hazards could reduce on road bicycle crashes which do not involve a motor vehicle. |
S0001457519311650 | Worldwide road crashes are a major course of death and serious injury . Police reports provide a rich source of data on the proximal causes of road traffic collisions . Yet road safety research has raised concerns about the quality and reliability of police reported data . In the UK crash report form contributory factors are categorised to aid police officers in identifying appropriate factors . However discord between the classification of contributory factors in crash reports and police officers own categorical perceptions may lead to misunderstanding and in turn misreporting of contributory factors . The current investigation recruited 162 police officers to report their perceptions of the relations among contributory factors in the UK crash report form . Hierarchical clustering analysis was used to identify an optimal category structure based on police officers perceptions . The clustering analysis identified a classification system with seven or eleven categories of contributory factors maximising the internal coherence of categories and minimising discord with police officers perceptions . The findings also yield new insights into police officers perceptions of crash causation and demonstrate how statistical techniques can be used to inform the design of road traffic collision report forms . | 1 Police reports provide a wealth of data on the causes of road traffic collisions. 2 Discord between report procedures and users perceptions can cause reporting errors. 3 Hierarchical clustering minimised report procedure and user perception discord. 4 New insights are revealed by police officers perceptions of crash causation. |
S0001457519311728 | Emergency response drivers are often required to engage in high risk driving manoeuvres on their way to a reported incident . Such risk requires that these drivers receive a high level of training and continued development . The aim of this paper was to investigate an innovative format for a new potential tool that could support the training and assessment of these drivers a single clip Holistic Hazard Test containing multiple hazards in a single route . In study one we created a proof of concept 15 minute clip containing hazards multiple choice questions and probes to collect self reported safety ratings . ERDs were more accurate on the multiple choice questions than a control group though response time scores to hazards did not reach the threshold for significance . In study two we refined the development process and created a series of new holistic hazard tests across four counties of the East Midlands UK . Each test contained many hazards and MCQs that assessed situation awareness and decision making based on the results of study 1 . Participants were recruited across the four counties and were presented with both the test that was specific to their county and one of the unfamiliar location tests in order to assess the generalisability of the tests across different locales . The results showed no differences regarding location familiarity suggesting that tests filmed in one area of the country can be viewed by drivers elsewhere without detriment to performance . ERDs once again responded to MCQs more accurately and also scored more hazard points on the basis of faster responses to hazards compared to control participants . These results suggest such tests can successfully tap into ERD specific skills with regard to spotting predicting and responding to hazards on the road . We recommend refinement of this tool for assessment of emergency response drivers and further development to extend the materials to create a training tool . | We designed. containing hazards and multiple choice questions for emergency response drivers ERDs . Across two studies experienced ERDs outperformed control drivers. No effect of route familiarity was observed. This test may be suitable for ERDs at the initial stage of training. |
S0001457519311753 | For safety purposes it is critical that bicyclists be conspicuous to drivers . We report two experiments that investigated the benefits of bicycle taillights and fluorescent clothing for enhancing the bicyclists rear conspicuity in daylight . In Experiment 1 24 participants sat in a car parked on a closed road at each of three distances and rated the conspicuity of four bicyclists displaying taillights that varied in their placement intensity and mode . The results confirmed that bicycle taillights can significantly enhance conspicuity in daylight . Varying the placement of the taillights revealed that having an always on taillight mounted to each of the riders ankles was the most conspicuous location to mount taillights and this effect was particularly strong at greater viewing distances . For seat post mounted taillights flashing taillights were rated as more conspicuous . In Experiment 2 186 participants were passengers on a short drive during which they pressed a button each time they recognized that a bicyclist was present . Each participant passed a test bicyclist wearing one of four clothing configurations . When the cyclist wore a fluorescent yellow jersey paired with fluorescent yellow leg covers participants responded from a distance that was 3.3 times greater than when the cyclist wore the same jersey without the yellow leg covers . Both of these experiments demonstrate that highlighting bicyclists pedaling motion enhances their conspicuity when viewed from behind . These results further emphasize the conspicuity benefits of biological motion and provide bicyclists with techniques to enhance their own conspicuity in daylight . | In daylight ratings of bicyclist rear conspicuity were higher when rear facing lights were mounted to the bicyclists ankles than when a taillight was mounted to the seat post either on or off or to the helmet. When a taillight was mounted to the seat post daytime conspicuity ratings were higher when the taillight was flashing than when it was always on. In daylight the distance from which participants recognized the presence of a bicyclist was over 3 x greater when the bicyclists fluorescent yellow jersey was paired with matching leg covers than when the leg covers were absent. Thus bicyclists can significantly enhance their rear conspicuity in daytime by using active lighting or fluorescent garments to highlight their pedaling movements. |
S0001457519311790 | Detecting traffic accidents as rapidly as possible is essential for traffic safety . In this study we use eXtreme Gradient Boosting a Machine Learning techniqueto detect the occurrence of accidents using a set of real time data comprised of traffic network demographic land use and weather features . The data used from the Chicago metropolitan expressways was collected between December 2016 and December 2017 and it includes 244 traffic accidents and 6073 non accident cases . In addition SHAP is employed to interpret the results and analyze the importance of individual features . The results show that XGBoost can detect accidents robustly with an accuracy detection rate and a false alarm rate of 99 79 and 0.16 respectively . Several traffic related features especially difference of speed between 5 min before and 5 min after an accident are found to have relatively more impact on the occurrence of accidents . Furthermore a feature dependency analysis is conducted for three pairs of features . First average daily traffic and speed after accidents non accidents time at the upstream location are interpreted jointly . Then distance to Central Business District and residential density are analyzed . Finally speed after accidents non accidents time at upstream location and speed after accidents non accidents time at downstream location are evaluated with respect to the models output . | Develop an XGBoost model to detect accidents with detection rate of 79 and AUC of 89 . The developed model is robust and interpretable thanks to SHAP. Complex interrelated impacts of selected features are captured and analyzed. |
S0001457519311807 | Previous studies have focused on the impact of visibility level on drivers behavior and their safety in foggy weather . However other important environmental factors such as road alignment have not been considered . This paper aims to propose a methodology in investigating rear end collision avoidance behavior under varied foggy conditions with focusing on changes in visibility and road alignment in this study . A driving simulator experiment with a mixed 246 factor design was conducted using an advanced high fidelity driving simulator . The design matrix includes two safety critical conditions four visibility conditions and six road alignment situations . Behavior variables from different dimensions were identified and compared under varied conditions . To estimate the safety of drivers a time based measurement speed reduction time is selected among the variables as a measure of safety . The survival analysis approach was introduced to model the relationship between environmental factors and driver safety using speed reduction time as the survival time . Both the Kaplan Meier method and the COX model were applied and compared . Results generally suggest that reduced visibility leads to more dangerous rear end collision avoidance behavior from different aspects . Though findings are mixed regarding the road alignment the impact of the road alignment was found to be significant . Interestingly conditions of downward slope were found to be safer . Overall the COX model outperformed the Kaplan Meier method in understanding the impact of environmental factors and it can be applied to investigate other contributing factors for freeway safety under foggy weather conditions . | Impact of road alignment on driver behavior in fog has not been addressed. An experiment on the high fidelity OKTAL driving simulator Tongji was conducted. Driver behavior in different foggy conditions was studied from different dimensions. Safety analysis was conducted using the survival analysis approach. Visibility positively affect safety findings are mixed regarding road alignment. |
S000145751931190X | Intersections represent the most dangerous sites in the road network for pedestrians not only is modal separation often impossible but elements of geometry traffic control and built environment further exacerbate crash risk . Evaluating the safety impact of intersection features requires methods to quantify relationships between different factors and pedestrian injuries . The purpose of this paper is to model the effects of exposure geometry and signalization on pedestrian injuries at urban signalized intersections using a Full Bayes spatial Poisson Log Normal model that accounts for unobserved heterogeneity and spatial correlation . Using the Integrated Nested Laplace Approximation technique this work leverages a rich database of geometric and signalization variables for 1864 intersections in Montreal Quebec . To collect exposure data short term pedestrian and vehicle counts were extrapolated to AADT using developed expansion factors . Results of the model confirmed the positive relationship between pedestrian and vehicle volumes and pedestrian injuries . Curb extensions raised medians and exclusive left turn lanes were all found to reduce pedestrian injuries while the total number of lanes and the number of commercial entrances were found to increase them . Pedestrian priority phases reduced injuries while the green straight arrow increased injuries . Lastly the posterior expected number of crashes was used to identify hotspots . The proposed ranking criteria identified many intersections close to the city centre where the expected number of crashes is highest and intersections along arterials with lower pedestrian volumes where individual pedestrian risk is elevated . Understanding the effects of intersection geometry and pedestrian signalization will aid in ensuring the safety of pedestrians at signalized intersections . | This paper models the effects of exposure geometry and signalization on pedestrian injuries at signalized intersections. Full Bayes spatial models were estimated using the INLA technique on a rich database of intersections in Montreal Quebec. Traffic exposure curb extensions raised medians and exclusive left turn lanes were associated with pedestrian injuries. Total lanes and commercial entrances increased injuries while pedestrian priority phases reduced injuries. Hotspot analysis identified dangerous sites based on total crashes and crash rates. |
S0001457519311960 | This paper proposes an approach to rationally set automated vehicles car following behavior that explicitly balances between the competing considerations of safety and efficiency . The specification of safety and efficiency are both based on empirically supported concepts and data . In numerical analyses with empirical vehicle trajectories at two sites we demonstrate intuitive response to systematic variation in numerical values selected as inputs as well as whether the scope of the efficiency consideration is selfish or systemwide . The proposed balancing is aligned with the standard Hand Rule criterion to demonstrate that a duty of care has been met in which a burden must be borne if it is less than the product of the probability of loss to a third party and the magnitude of loss . Thus the proposed approach is intended to be useful for designers of control algorithms for AVs to establish that they have met their duty of care taking both safety and efficiency into account . | Explicit balancing of safety and efficiency to specify the car following behavior of AVs. Safety specified via crash risk severity of crash and monetary cost of crashes. Efficiency specified via Value of Time considering impacts on arrival time. Numerical case study demonstrates tractability intuitive sensitivity to stimulus. Explicit balancing supports demonstrating that a duty of care has been met. |
S0001457519312011 | Culpability analysis was conducted on 5000 drivers injured as a result of a vehicular collision and in whom comprehensive toxicology testing in blood was conducted . The sample included 1000 drivers for each of 5 years from approximately 50006000 drivers injured and taken to hospital in the State of Victoria . Logistic regression was used to investigate differences in the odds of culpability associated with alcohol and drug use and other selected crash attributes using the drug free driver as the reference group . Adjusted odds ratios were obtained from multivariable logistic regression models in which other potentially explanatory driver and crash attributes were included . Drivers with alcohol present showed large increases in the odds of culpability similar to that seen in other studies investigating associations between blood alcohol concentration and crash risk . Methylamphetamine also showed a large increase in the odds of culpability compared to the reference group at both below and above 0.1mg L whereas those drivers with | Culpability analysis was conducted on 5000 injured drivers in whom drug testing was conducted. Alcohol gave large increases in the odds of culpability that was concentration dependent. Methylamphetamine also showed a large increase in the odds of culpability. THC gave a modest increase in the odds of culpability. Benzodiazepines also gave a modest increase in the odds of culpability. |
S0001457519312059 | Roadway departure crashes contribute to a large proportion of fatal and injury crashes in the United States . These crash types are more likely to occur along horizontal curve sections of a roadway . Countermeasures that prevent vehicles from departing the roadway is one method to mitigate roadway departure crashes . Pennsylvania has deployed on pavement horizontal curve warning markings in advance of horizontal curves on two lane rural highways as a roadway departure crash reduction strategy . This study used an Empirical Bayes before after study design to evaluate the safety effects of the horizontal curve warning pavement markings . A total of 263 treatment sites and more than 21 000 reference sites were included in the evaluation . Crash modification factors were developed for total fatal plus injury run off road nighttime nighttime run off road and nighttime fatal plus injury crashes . The point estimates for each of these crashes ranged from 0.65 to 0.77 the results were statistically significant for total and fatal plus injury crashes at the 95th percentile confidence level . | Horizontal Curve Warning Pavement Markings in Pennsylvania were Evaluated. Empirical Bayes Before After Analysis was Used. Multiple crash types and severities along horizontal curves were considered. Findings indicate that the pavement markings reduce run off road crashes by 2335 . |
S0001457519312072 | Using the Alcohol Use Disorders Identification Test Korean revised version we examined the association between habitual alcohol use and risk taking behaviors among car users . We used the data of 15 043 car users aged 20 years or older from the Korea National Health and Nutrition Examination Survey conducted between 2009 and 2013 . Multivariable logistic regression analysis was used to investigate the associations between alcohol use and risk taking behaviors while adjusting for individual level covariates . Compared to low risk drinkers high risk drinkers 2.18 95 CI 1.962.42 and intermediate risk drinkers had higher odds of risk taking behaviors while using a car . Stratifying by sociodemographic variables led to differences in the relationship between alcohol drinking level and risk taking behaviors . Furthermore alcohol drinking level had significant positive associations with most of risk taking behaviors especially driving under the influence of alcohol and using a car with a drunken driver . Car users with high levels of alcohol consumption are more likely to be involved in risk taking behaviors especially in driving under the influence of alcohol . While causal relations can not be established due to the nature of the cross sectional design it is possible that individuals habitual alcohol consumption level can influence their risk taking behaviors while using a car . | Alcohol use was related to risk taking behavior while using a car among Koreans. This association was stronger in men youth and dwellers in higher incidence of traffic accident. The association was also strongest for driving under the influence of alcohol. An evidence of association between habitual drinking and risk behaviors which possibly lead to traffic accidents was seen. |
S0001457519312084 | Research on the effect of advertising billboards on road safety has accumulated over the past seven decades but has led to inconclusive data which prevent clear cut conclusions . To enhance road safety it was suggested that researchers should shift their efforts to exploring which billboard characteristics are distracting by nature . This line of research may promote the establishment of concrete guidelines for the least distracting permissible billboards . A previous study classified billboards into three clusters 1 . Loaded 2 . Graphical and 3 . Minimal . The current study systematically explores the effect of these three clusters on drivers performance in a driving simulator . Eighteen participants drove in scenarios which systematically manipulated the following variables the perceptual load on the road the perceptual load on the sides of the road location of preplanned critical events and the presence of billboards from each one of the three previously identified clusters . The findings show that the presence of billboards from the Loaded and Minimal clusters significantly compromised road safety in various experimental conditions . However the presence of billboards from the Graphical cluster significantly affected drivers performance only in one experimental condition . The conclusion for the time being is that Graphical billboards which include a large quantity of graphic elements with few or no textual elements are the least harmful while driving . | Simulator study tested the effect of ads clusters. deteriorated drivers reactions to critical events. hardly affected the reactions to critical events. are suggested as the least harmful cluster while driving. |
S0001457519312102 | Understanding driver behavior of conditionally automated driving is necessary to ensure a safe transition from automated to manual driving . This study aimed to examine the difference in take over performance between high crash risk and lower crash risk drivers in emergency take over situations during conditionally automated driving . In the current simulator study a 33 factorial design was used including the task factors and time budget factors . Forty eight participants completed a test drive on an approximately 10km long two way six lane urban road . The participants firstly were in manual control and then switched to the automated driving mode at a speed of 50km h. The automated driving system was able to detect a broken car in the ego lane and requested the driver to take over the control of the vehicle . There are at least one or two other vehicles or motorcycles on each side of the ego vehicle resulting in fewer escape paths . For the two non handheld non driving related tasks the participants were asked to be fully engaged in a task without any need to monitor the road environments . Each participant completed nine emergency take over situations . The participants were classified into two groups that were labeled LCR and HCR drivers according to the number of accidents per driver . The results show that LCR drivers had shorter brake reaction time compared to HCR drivers . For all drivers the engagement in a task led to longer response times and the time budget affected the longitudinal vehicle control . In addition the task affected the response times for LCR and HCR drivers but only the time budget affected the longitudinal vehicle control for LCR drivers . For all drivers LCR and HCR drivers the time budget and task affected the safety of take over . Especially the two non handheld everyday tasks seem to have a similar effect on the drivers workload . Therefore the HCR drivers had a lower hazard perception compared to the LCR drivers and the factor regarding the individual difference of driving ability in take over situations should be considered to design safe take over concepts for automated vehicles . | A driving simulator study examined the effects of time budget and task on take over performance for lower crash risk LCR and high crash risk HCR drivers. LCR drivers had shorter brake reaction time compared to HCR drivers. Reading the news and watching a video seem to have a similar effect on the drivers workload. |
S0001457519312205 | Several factors may influence the decision to drink drive in young drivers such as the amount of alcohol consumed exposure to an in vehicle alcohol feedback device and subjective responses to alcohol . Understanding of their influence on DD is lacking and may be key for targeted intervention . This randomized controlled double blinded driving simulation experiment tested three main hypotheses young drivers are more likely to engage in DD with i lower alcohol dose ii lack of exposure to an in vehicle alcohol feedback device and iii lower subjective responses to alcohol intoxication . Interactions between the decision to DD and SR FB and sex were also explored . Males and females aged 2024 years old were randomly assigned to two conditions i alcohol dose and ii exposure to an in vehicle alcohol feedback device . Assessment of participants SR following alcohol intake was based upon two measures i subjective intoxication measured by the discrepancy between an objective measure of intoxication and their subjective estimate of intoxication and ii perception of capacity to drive safely under alcohol . Participants were then asked to make either a negative or positive decision to DD while confronted with time based contingencies related to their decision . Logistic regression and moderation analyses tested hypotheses . Approximately 60 of participants decided to DD . Higher odds of DD were found in participants reporting higher capacity to drive adjusted odds ratio Lower SR was found to be associated with a greater likelihood of the decision to DD in young drivers while exposure to an in vehicle FB device had no effect on DD . Importantly FB exposure appeared to disrupt the relationship between lower SR and the decision to DD signaling that FB may be selectively effective for young drivers possessing lower SR. Future studies are needed to clarify whether FB technology and other interventions can be targeted to deter DD in the young drivers most likely to benefit . | Approximately 60 of participants decided to engage in drink driving in simulation. Perceived higher capacity to drive and male sex predicted decision to drink drive. Higher capacity to drive predicted drink driving for participants not exposed to alcohol feedback. Exposure to feedback disrupted the relationship between higher capacity to drive and drink driving. |
S0001457519312230 | Delivery riders an occupation that has emerged from Chinas booming E commerce industry have attracted widespread attention due to their red light running and high accident rates . This study aimed to utilize the theory of planned behavior to investigate the psychological characteristics of delivery riders RLR intentions . A survey questionnaire was designed to collect data including information regarding the extended variables the basic components of the TPB and demographic characteristics . The survey was conducted in Xi an and 228 complete questionnaires were collected . Structural equation modeling was used to examine the data and a multiple group analysis of the demographic variables was conducted . The results showed that the expanded TPB model had a better model fit and higher variance explanation than the original TPB model . Extended constructs i.e . conformity tendency and the traffic environment were significant predictors and attitude was the strongest predictor of all the examined variables related to RLR intentions . Finally the path parameters of the expended TPB model were adapted for different demographic groups and some differential effects were also found . These results could provide a basis for the design of intervention measures and safety education schemes by delivery platforms and traffic management departments to reduce RLR behavior among delivery riders . | The theory of planned behavior was used to investigate the behavior of delivery riders running red lights. The structural equation model was used to predict delivery riders running red lights. Attitude conformity tendency and the traffic environment were significant predictors in the modified TPB model. The results of multiple group analysis show that differences between the means of psychological variables of different population groups. Some intervention measures are obtained by analyzing the influencing factors of running red lights. |
S0001457519312266 | This paper 1 analyzes the extent to which drivers engage in multitasking additional to driving under various conditions 2 specifies odds ratios of crashing associated with MAD and 3 explores the structure of MAD . Data from the Second Strategic Highway Research Program Naturalistic Driving Study was analyzed to quantify the prevalence of MAD in normal driving as well as in safety critical events of various severity level and compute point estimates and confidence intervals for the corresponding odds ratios estimating the risk associated with MAD compared to no task engagement . Sensitivity analysis in which secondary tasks were re defined by grouping similar tasks was performed to investigate the extent to which ORs are affected by the specific task definitions in SHRP2 . A novel visual representation of multitasking was developed to show which secondary tasks co occur frequently and which ones do not . MAD occurs in 11 of control driving segments 22 of crashes and near crashes 26 of Level 13 crashes and 39 of rear end striking crashes and 9 16 17 and 28 respectively for the same event types if MAD is defined in terms of general task groups . The most common co occurrences of secondary tasks vary substantially among event types for example Passenger in adjacent seat interaction and Other non specific internal eye glance tend to co occur in CNC but tend not to co occur in control driving segments . The odds ratios of MAD using SHRP2 task definitions compared to driving without any secondary task and the corresponding 95 confidence intervals are 2.38 for CNC 3.72 for Level 13 crashes and 8.48 for rear end striking crashes . The corresponding ORs using general task groups to define MAD are slightly lower at 2.00 for CNC 3.03 for Level 13 crashes and 6.94 for rear end striking crashes . The number of secondary tasks that the drivers were engaged in differs substantially for different event types . A graphical representation was presented that allows mapping task prevalence and co occurrence within an event type as well as a comparison between different event types . The ORs of MAD indicate an elevated risk for all safety critical events with the greatest increase in the risk of rear end striking crashes . The results are similar independently of whether secondary tasks are defined according to SHRP2 or general task groups . The results confirm that the reduction of driving performance from MAD observed in simulator studies is manifested in real world crashes as well . | Prevalence structure and safety risk of multitasking additional to driving MAD were analyzed using driving data in SHRP2. MAD occurs in 11 of control driving segments 22 of crashes and near crashes and 39 of rear end striking crashes. A new graph representation for secondary task prevalence and co occurrence was introduced. MAD significantly increases crash risk compared to no task engagement. Using general secondary task definitions to define MAD gives results with similar patterns. |
S0001457519312278 | The current study had three aims 1 describe distracted driving beliefs among adolescents by various distraction types 2 examine the factor structure of distracted driving beliefs and 3 test whether individual difference factors shown in prior work to be related to distracted driving behavior significantly predicted factors of distracted driving beliefs . Three hundred seventy nine high school students enrolled in non mandatory Drivers Education courses completed surveys of distracted driving beliefs sensation seeking and demographics . A factor analysis revealed four factors of distracted driving beliefs 1 self acceptance of interacting with a cell phone while driving 2 perceived peer acceptance of interacting with a cell phone while driving 3 perceived threat of distracted driving to personal safety and 4 self and peer acceptance of talking on a cell phone while driving . Adolescents perceived a greater threat to safety and less self and peer acceptance of interacting with cell phones while driving than talking on a cell phone while driving . In general men those with more driving experience higher in sensation seeking and those placing more importance on checking notifications on a phone had riskier beliefs about distracted driving . Findings suggest adolescent distracted driving beliefs are influenced by individual difference factors providing some knowledge about the motivations for distracted driving . Future work should consider novel strategies for intervening to reduce this common yet extremely dangerous behavior among adolescents . | Beliefs about distracted driving varied by distraction type talk vs interacting . Factor analyses suggested distracted driving beliefs are multifaceted. Individual difference factors predicted distracted driving beliefs. |
S000145751931228X | Excessive alcohol use especially binge drinking is an important risk factor for unintentional and intentional injuries . This study used hospital discharge data to estimate the prevalence and trends of treatments for alcohol related injury in Minnesota and discussed opportunities and challenges for public health surveillance . We examined hospital treated ARI in Minnesota between 2000 and 2015 using HDD . ARI was defined as hospital discharges with an injury diagnosis and a diagnosis related to alcohol in any diagnosis field . The number of hospital treated injuries increased by 30 between 2000 and 2015 . The number of those injuries that were alcohol related increased by 166 from 2000 to 2015 . ARI were more likely to be treated as inpatients than all injuriesin 2015 34 of ARI were inpatient compared to 17 of all injuries . Patients treated for ARI were more likely to be male and older than the average injury patient . In 2015 ARI were more likely than all injuries to be self inflicted related to assault and less likely to be unintentional . These analyses suggest that the rate of hospital treated ARI increased more steeply from 2000 to 2015 than all injuries . While there are significant challenges to using HDD for surveillance further work to assess the validity of the data source is warranted . | Hospital treatments for alcohol related injuries increased significantly. Alcohol related injury patients were more likely to be hospitalized. Alcohol related injuries were more likely to be violence related than all injuries. Further validation of hospital discharge data is needed. |
S000145751931231X | Considerable studies have been conducted to investigate the tunnels traffic safety . However the entrance and exit parts of a tunnel are mostly considered symmetrical in previous studies and the different lengths of tunnels have not been separately studied . This study aims to investigate the characteristics of traffic crashes in freeway single tunnels by separately considering the entrance and exit of the tunnel as well as the different lengths of tunnels . A six zone approach is proposed and the data from 156 single tunnels in Hunan province China are applied for safety analysis . The crash rate crash type and contributing crash factors are compared between the conventional four zone approach and the proposed method and the three types of tunnels with different lengths are also compared for in depth analysis . | A six zone approach is proposed for the safety analysis of freeway single tunnels. The crash rate crash type and contributing factors vary for the different zones of the tunnel. The crash characteristics vary for the different types of tunnels long medium and short . Several countermeasures for improving freeway single tunnel safety are recommended. |
S0001457519312357 | Although only 2 of crashes are head on crashes in the United States they account for over 10 of all crash related fatalities . This study aims to investigate the contributing factors that affect the injury severity of head on crashes and develop appropriate countermeasures . Due to the unobserved heterogeneity inherent in the crash data a latent class clustering analysis is firstly conducted to segment the head on crashes into relatively homogeneous clusters . Then mixed logit models are developed to further explore the unobserved heterogeneity within each cluster . Analyses are performed based on the data collected from the Highway Safety Information System from 2005 to 2013 in North Carolina . The estimated parameters and associated marginal effects are combined to interpret significant variables of the developed models . The proposed method is able to uncover the heterogeneity within the whole dataset and the homogeneous clusters . Results of this research can provide more reliable and insightful information to engineers and policy makers regarding the contributing factors to head on crashes . | This paper examines injury severity of head on crashes in North Carolina. Latent class clustering analysis is conducted to reduce heterogeneity in the crash dataset. Mixed logit models are developed to further capture unobserved heterogeneity within clusters. Some variables are found to have random effects across observations in specific clusters. Relevant countermeasures are developed and future research directions are discussed. |
S0001457519312370 | Automated vehicles the wide adoption of which is expected to improve traffic safety significantly are penetrating our roads . The AVs that are testing on public roads have been bullied by human road users . We are not sure whether the bullying incidents are isolated or will be common in the future . In a cross national survey | We designed an eleven item bullying intention questionnaire. Participants in China and South Korea had a greater intention to bully AVs than to bully other human drivers. Chinese vs. Korean participants reported a greater intention to drive aggressively. Male vs. female participants reported a greater intention to drive aggressively. Younger vs. older participants reported a greater intention to drive aggressively. |
S0001457519312643 | Pedestrian avoidance algorithms often tacitly assume that the maneuver which minimizes collisions will also be the safest maneuver . This work shows that this is not always the case when considering pedestrian fatalities . Given the unavoidable uncertainty in vehicle motion environmental parameters and pedestrian behavior emergency avoidance maneuvers often involve some chance of a collision . Maneuvers that aim to keep the vehicle as far away from the pedestrian as possible will theoretically minimize collisions but if this strategy is followed and a collision occurs nonetheless it will often be at a higher speed than would occur with alternative strategies . This is a result of the tires friction ellipse which enforces a constraint between steering versus braking for collision avoidance braking must be reduced if pedestrian clearance is to be maximized . This work shows that in some common pedestrian collision situations the net effect of this increase in vehicle speed for pure avoidance offsets the benefits of reducing collisions . Pedestrians if hit would be hit at higher speeds leading to a net reduction in pedestrian survivability for collision minimizing maneuvers . First this trend is demonstrated and explained using a simplified point mass model of a vehicle which is then verified with a higher fidelity vehicle model as well as experimental maneuvers with an instrumented vehicle . While real accidents involve dozens of important parameters this research provides a general framework for an under recognized effect under certain common conditions . The implication of this finding suggests that future research in pedestrian avoidance should consider fatality minimization as an alternative objective to collision minimization . | Simulations show minimizing pedestrian vehicle collisions may increase fatalities. Increased speed during collision minimization is the cause of increased fatalities. Braking is often the fatality minimizing maneuver. |
S0001457519312680 | Surrogate measures of safety attract revived interest thanks to the advancements in traffic observations techniques and the growing need for rapid safety evaluation . A new method of safety analysis based on failure caused traffic conflicts and the Lomax distribution was recently proposed to estimate crash frequency more efficiently than with crash data . This paper has two objectives demonstrate the method applicability to near departure data collected in a driving simulator and provide initial evidence of the method validity . | Road departures are analyzed in a driving simulator with failure caused near departures. The method connects drivers behavior with the risk of road departure. The results exhibit the patterns prompted by the theory. The tested method provides insight into the research subject. The experiment time is reduced because departures do not have to be observed. |
S0001457519312746 | This study examines the relationship between two variablesmindfulness and incomewith regards to their relationship to the use of smartphones by young drivers which has been known to increase the likelihood of car accidents endangering young drivers and other road users . The study focuses on the relationship between these variables and the use of smartphones while driving and how this relationship differs between males and females . The study sample included 221 young drivers who were legally permitted to drive without supervision . The subjects were first asked to complete questionnaires on mindfulness and income . Next their smartphone use while driving was monitored over a one month period . This study is unique as it used an objective smartphone monitoring application to count the number of times the young participants actually touched their smartphones while driving . The findings show that the effects of social and personal factors on the use of smartphones while driving are significant for males but not for females . Most studies that investigate differences between males and females with respect to safety focus on differences in the averages of safety related variables . In the current study however we identified differences in relationships between variables and demonstrated that what predicts safety related behavior in males may not be a good predictor for females . Mindfulness and income can be used to identify male populations that are at risk of using smartphones while driving . Interventions that improve mindfulness can be used to reduce the use of smartphones by male drivers . | Males who are high on mindfulness use their smartphones less while driving than do males who are low on mindfulness. Males with low incomes use their smartphones more while driving than do males with high incomes. Income and mindfulness are not related to the level of smartphone use by female drivers. |
S0001457519312758 | In this study we test the widely held belief that young workers are less likely than adults to speak up about safety concerns . Counter to this belief and in line with age related resource selectivity theory we hypothesized that older workers would actually be less likely than younger workers to speak up about workplace safety concerns when their supervisors are unclear about their own commitment to safety . To test this we created two realistic scenarios in which we manipulated clarity of supervisor commitment to safety it is clear the supervisor clearly cares about is open to hearing suggestions about safety and it is unclear whether the supervisor cares about is open to hearing suggestions about safety . We randomly assigned participants | We test the belief that young workers are less likely than adult workers to speak up about safety concerns. Under clear supervisor commitment to safety younger and adult workers did not differ on their safety voice intentions. Under unclear supervisor commitment to safety adult workers were less likely to speak up about safety compared to younger workers. These findings have implications for our understanding of young and adult worker safety voice. These findings also highlight the importance of how supervisors signal commitment to safety. |
S0001457519312771 | Discretionary lane changing is one of the complex driving manoeuvres that requires surrounding traffic information for efficient and safe manoeuvring . The connected environment not only provides such information but also increases situational awareness which is useful for DLC decision making . However the literature is devoid of any concrete evidence of such impact of the connected environment on DLC decision making . As such this paper analyses the effects of the connected environment on DLC behaviour . Seventy eight participants from a diverse background performed DLCs in randomised driving conditions using the CARRS Q advanced driving simulator . These driving conditions are baseline connected environment with perfect communication and connected environment with communication delay . Various key driving behaviour indicators are analysed and compared using a linear mixed model . To analyse the effects of the connected environment on DLC decision making two Generalised Estimation Equation models are developed for gap acceptance and DLC duration . In addition a Weibull accelerated failure time hazard based duration model is developed to investigate the impact of the connected environment on safety associated with DLC manoeuvres . We find that drivers in the connected environment have a larger spacing larger lead and lag gaps a longer DLC duration and a lower acceleration noise compared to the baseline condition . The GEE model on gap acceptance reveals that drivers tend to select relatively bigger gap sizes when the connected environment offers them the subsequent gap information . Similarly the GEE model for DLC duration suggests that the connected environment increases DLC durations by 2.22 s and 2.11 s in perfect communication and communication delay driving conditions respectively . Finally the hazard based duration model provides insights into the probability of avoiding a lane changing collision and indicates that the probability of a lane changing collision is less in the connected environment driving conditions than in the baseline scenario . Overall the connected environment improves the DLC driving behaviour and enhances traffic safety . | Focused on the connected environments impact on discretionary lane changing decision making. Modeled the connected environments impact on safety associated with DLC manoeuvres. Developed a Generalised Estimation Equation model for gap acceptance. Modelled the duration of discretionary lane changing. |
S0001457519312825 | Wet skid resistance is of paramount importance for road safety as it has been recognized to affect wet road accidents . Recently European Regulations are introducing mandatory classification for tyre friction performance by means of tyre labelling procedure . In this paper an experimental study has been carried out in order to search for a relationship between indexes employed in the tyre and pavement classification . Coupled friction tests have been performed in a controlled manner on five test track with varying texture properties and significant statistical relationship has been derived between Wet Grip Index as defined in the European Tyre Labelling Procedure and the International Friction Index according to World Road Association friction harmonization experiment . If a temperature correction of skid data is applied a good correlation between WGI and IFI can be obtained . Although the experimental study has to be integrated with a wider measurement campaign preliminary results seem to indicate that a unified wet tyre road classification can be pursued allowing a better awareness of the road safety level among road users . | Bridging the gap among the research on tyre performance and that on the pavement skid resistance. Road Skid Classification based on objective criteria complaint with commercial tyres specifications to increase safety awareness in road users. In depth Review of relationship between tyre road friction and temperature. Prediction of real grip performance of commercial tyres on wet pavement surfaces based on conventional skid resistance measurement. |
S0001457519312886 | This paper investigates the effect of High Visibility Enforcement programs on different types of aggressive driving behavior namely speeding tailgating unsafe lane changes and other aggressive driving behavior types . For this purpose the Second Strategic Highway Research Program Naturalistic Driving Study data are used which include forward facing videos and time series information with regard to trips conducted at or near the locations of HVE implementation . To capture the intensity and duration of speeding and tailgating scaled metrics are developed . These metrics can capture varying levels of aggressive driving behavior enabling thus a direct comparison of the various behavioral aspects over time and among different drivers . To identify the effect of HVE and other trip driver vehicle or environmental factors on speeding and tailgating while accounting for possible interrelationship among the behavior specific scaled metrics Seeming Unrelated Regression Equation models were developed . To analyze the likelihood of occurrence of unsafe lane changes and other aggressive driving behavior types a grouped random parameters ordered probit model with heterogeneity in means and a correlated grouped random parameters binary logit model were estimated respectively . The results showed that drivers awareness of HVE implementation has the potential to decrease aggressive driving behavior patterns especially unsafe lane changes and other aggressive driving behaviors . | Developed scaled metrics to capture intensity and duration of aggressive driving. Several surrogate safety measures were investigated. Unobserved heterogeneity was accounted for in all statistical models. Results show that high visibility enforcement has the potential to improve safety. |
S0001457519312904 | This study investigates spatial dependencies between frequency and within severity of vehicle crashes caused by distracted driving along with the role of the built and socio demographic environments in the Columbus Metropolitan Area Ohio . We adopt a full Bayesian hierarchical framework with Multivariate Conditional Autoregressive Priors to account for the complex spatial correlation structure as well as the unobserved heterogeneity . Using aggregated crash count data for the 414 census tracts the analysis outcomes reveal that census tracts providing more jobs and having a higher proportion of commercial land use would have higher likelihood of relative crash risks in both severity levels . Inclusion of correlation structure between frequency as well as within crash severity level has proven a significant increase on the performance of the model verifying influences of space on the frequency and severity of distraction affected vehicle crashes . In addition this research presents areas of higher relative risks that have 1.5 times elevated risk of collision than other census tracts . The identification of areas of excessive risks informs us to devise policies to mitigate negative consequences of distraction affected crashes . | Spatial influence on the frequency and severity of vehicle crashes by driving in distraction is examined. A multivariate Bayesian approach captures the unobserved spatial impacts on the relative risk of distraction affected vehicle crashes. Location of census tracts with elevated risks has been identified and this can provide guidance to where to allocate scarce safety resources. Census tracts providing more jobs and having a higher share of commercial land use are likely to have higher risk in both severity levels. Findings about the risks of teenagers allow policymakers to devise proper strategies to reduce the risk of distracted driving. |
S0001457519312928 | Drivers apply brakes to reduce the speed of a vehicle based on the perceived risk while approaching a certain event . Inadequate or excessive braking can lead to serious consequences . The current study analyses the braking behaviour and accident probability of the drivers under increasing time pressure conditions . Two perilous events were designed to examine Brake Pedal Force and Brake To Maximum Brake transition time on a driving simulator . Eighty five Indian licensed drivers drove the simulator in three different time pressure conditions No Time Pressure Low Time Pressure and High Time Pressure . Random parameters Tobit model was used for analysing BPF and duration analysis approach was considered for BTMB analysis . Further generalized linear mixed model with logit link function was used to study the effect of BPF and BTMB on accident probability of the drivers . The model results showed that gender driving profession approach speed age driving history and driving condition significantly affected braking behaviour of the drivers . It was observed that in pedestrian crossing event LTP and HTP driving conditions resulted in 42.31 and 87.28 increase in BPF and 13 and 23 reduction in BTMB respectively with respect to NTP driving condition and the corresponding changes were slightly lower in case of obstacle overtaking event . The accident probability model showed that female drivers needed 119.70 and 186.08 more BPF and 37.55 and 58.51 less BTMB in LTP and HTP driving conditions respectively to have equivalent risk levels as observed for male drivers . Further non professional drivers had to increase their BPF by 166.83 in LTP and 219.93 in HTP to offset their increased accident risk as compared to professional drivers under time pressure conditions . | Simulator study was conducted to test braking behvaiour in time pressure conditions. Experiments were performed with 85 drivers for increasing time pressure conditions. Increase in time pressure resulted in abrupt and aggressive application of brakes. Abrupt and aggressive braking lowered accident risk under time pressure conditions. |
S0001457519313089 | Employee safety citizenship behavior is critical for workplace safety in a high risk work environment but few studies have addressed how safety stressors affect SCB . This study investigates the different relationships between safety stressors and two forms of SCB . It also examines the moderating effect of safety specific trust within these relationships . An analysis of 332 multisource data from frontline workers and their safety supervisors in China reveals that safety role ambiguity and safety role conflict negatively affect proactive safety behaviors while interpersonal safety conflict impedes prosocial safety behaviors . Additionally cognition based safety trust alleviates the effects of safety role ambiguity and safety role conflict on proactive safety behaviors whereas affect based safety trust effectively restricts the influence of interpersonal safety conflict on prosocial safety behaviors . These results suggest that managers need to instill SCB in their subordinates and combat stressful conditions through interventions that enhance safety specific trust . | Safety citizenship behavior is critical for workplace safety in high risk industries. We explore the role of safety stressors on proactive and prosocial safety behaviors. The moderating role of safety specific trust in the relationships between safety stressors and two types of safety citizenship behavior is revealed. Workplace safety management can reduce accidents in high risk industries. |
S0001457519313120 | Researchers continue to seek reasons for novice drivers over representation in crashes . Evidence on how early interventions might mitigate this global phenomenon remains inconclusive . This study explores changes in novice drivers beliefs during pre licensure training and within their first one year independent provisional license period and how these changes might help to predict subsequent risky driving . A sample of novice drivers Reported driving self efficacy increased and fear of driving decreased from the beginning to the end of driver training and after one year follow up in both men and women . Road safety attitudes changed in the risk unfavourable direction from T1 to T2 . However at T3 these attitudes returned to the initial level for men . Female novice drivers reported the same level of safety attitudes at T2 and T3 . Risky attitudes driving self efficacy and fear of driving predicted reported driving errors and violations . Reported psychological changes occurred during the driver training period and in the first year of independent driving . It is recommended that special attention should be paid to a group of novices who experienced safety compromising changes in attitudes driving self efficacy and fear of driving during training and in the first year of their driving career . | Longitudinal study explored the changes in drivers beliefs from training. Driving self efficacy increased during training and in one year follow up. Fear of driving decreased during training and in one year follow up. Changes in road safety attitudes were non linear. Changes in beliefs added significantly to the prediction of risky driving. |
S0001457519313168 | This paper reports on an exploratory investigation of the influence of five different fatalistic belief constructs on three classes of self reported pedestrian behaviours and on respondents general attitudes to road safety and how relationships between constructs differ across countries . A survey of over 3400 respondents across Bangladesh China Kenya Thailand the UK and Vietnam revealed a similar pattern for most of the relationships assessed in most countries those who reported higher fatalistic beliefs or more external attributions of causality also reported performing riskier pedestrian behaviours and holding more dangerous attitudes to road safety . The strengths of relationships between constructs did however differ by country behaviour type and aspect of fatalism . One particularly notable country difference was that in Bangladesh and to a lesser extent in Kenya a stronger belief in divine influence over ones life was associated with safer attitudes and behaviours whereas where significant relationships existed in the other countries the opposite was true . In some cases the effect of fatalistic beliefs on self reported behaviours was mediated through attitudes in other cases the effect was direct . Results are discussed in terms of the need to consider the effect of locus of control and attributions of causality on attitudes and behaviours and the need to understand the differences between countries therein . | Questionnaire survey of 3423 respondents across six countries. Exploration of beliefs road safety attitudes and pedestrian behaviours. Stronger fatalistic beliefs associated with riskier attitudes and behaviours. Relationships were dependent on the specific factors of interest. Despite many similarities there were also significant between country differences. |
S0001457519313284 | Since its discovery at the end of the 1950s hydroplaning has been a matter of concern for drivers on wet roads because it can affect driver safety . Indeed this phenomenon can lead to a complete loss of contact between the tire and the road caused by the layer of water that develops between them resulting in a complete loss of longitudinal and lateral grip . | The importance of full hydroplaning as a main cause of traffic accident is badly known in the scientific literature. German In Depth Accident Study GIDAS enables to get relevant objective data from accidents. Associated to a physical analysis an evaluation of the share of full hydroplaning as accident main cause was conducted. It appears that full hydroplaning accident exists but they are much rarer than most driver think. |
S0001457519313417 | Inter national benchmarking of road safety with the purpose of achieving continuous improvement by learning lessons from existing best practices has currently been widely encouraged by most countries as an emerging management tool to improve the level of road safety . However performing a successful road safety benchmarking practice is by no means easy . Challenges exist from ascertaining the benchmarking framework at the very beginning to making final policy decisions . In this study based on the identification of leading road safety risk factors a comprehensive set of hierarchically structured safety performance indicators was developed some necessary data processing procedures were conducted and the use of data envelopment analysis for composite indicator construction was elaborated . An interval multiple layer DEA based CI model was proposed to take both the hierarchical structure of the indicators and the data uncertainty into account and was used to benchmark road safety performance for a set of European countries . Based on the model output best performing and underperforming countries were distinguished and all the countries were further ranked by computing their cross index score . Moreover by taking the characteristics of each country in the data set into account country specific benchmarks for those underperforming countries were identified and useful insight in the areas of underperformance in each country was gained . Meanwhile by summarizing the risk aspects that need urgent policy action for all these countries some specific road safety enhancing recommendations for this region as a whole were formulated . | A road safety performance benchmarking analysis was conducted for a set of European countries. An interval multiple layer DEA based composite indicator model was proposed. Both the hierarchical structure of the indicators and the data uncertainty were taken into account. Best performing and underperforming countries were distinguished and further ranked. Policy recommendations with respect to country specific benchmarks and action priorities were formulated. |
S000145751931379X | Driving with the aid of a navigation system could distract drivers . A high level of distraction influences driver performance and safety leading to a possible increase in road crashes . The illumination level and size of the GPS display may influence the duration and frequency of a drivers glances which in turn may affect driver distraction . In a simulated driving experiment requiring the use of a GPS the GPSs display size and illumination level were examined in light of the drivers experience and gender to understand their effects on the performance and safety of young drivers on roads in urban and rural areas . Twenty young subjects male and female between the ages of 18 and 29 years participated in this experiment . Driving safety was evaluated by lateral control number of crashes number of near misses and the total time out of the lane . Driving performance was evaluated by the number of navigational errors the total time making navigational errors number of times the speed limit was exceeded and total amount of time speeding . These measures were analyzed using a repeated measures analysis of variance model . Furthermore the effects of the GPS display considering the driving experience were investigated with a simple linear regression . Findings suggest that driving with a small GPS display in an urban area leads to more navigational errors than driving with a large GPS display . Furthermore more speed limit violations tend to occur in rural areas in the daytime than at night . Moreover in urban areas male drivers tend to have the highest number of crashes during the daytime . Furthermore in rural areas males tend to violate the speed limit more often and for longer periods of time during the daytime than at night and more than females do . Additionally when navigating with a GPS system young experienced drivers drive safer than inexperience drivers . The findings are of interest to designers and transportation researchers concerned with improving GPSs to enhance driving safety and performance . | Driving with a small GPS display in an urban area leads to more navigational errors than driving with a large GPS display. When navigating with a GPS system experienced drivers drive safer than their inexperience peers. Drivers in rural areas particularly males have more speed limit violations during the daytime than at night. In urban areas male drivers tend to have the highest number of crashes during the daytime. |
S0001457519313880 | Observed accidents have been the main resource for road safety analysis over the past decades . Although such reliance seems quite straightforward the rare nature of these events has made safety difficult to assess especially for new and innovative traffic treatments . Surrogate measures of safety have allowed to step away from traditional safety performance functions and analyze safety performance without relying on accident records . In recent years the use of extreme value theory models in combination with surrogate safety measures to estimate accident probabilities has gained popularity within the safety community . | Surrogate safety measures allow to analyze safety without relying on accidents. Using Extreme Value theory accident probabilities can be predicted. We extend existing efforts with bivariate EV models for the joint probability esimtation of two related accident events. Driver characteristics and road design significantly impact accident probabilities. We apply our proposed method to the safety analysis of passing maneuvers. |
S0001457519313892 | Road safety research in low and middle income countries is limited even though ninety percent of global road traffic fatalities are concentrated in these locations . In Colombia road traffic injuries are the second leading source of mortality by external causes and constitute a significant public health concern in the city of Bogot . Bogot is among the top 10 most bike friendly cities in the world . However bicyclists are one of the most vulnerable road users in the city . Therefore assessing the pattern of mortality and understanding the variables affecting the outcome of bicyclists collisions in Bogot is crucial to guide policies aimed at improving safety conditions . This study aims to determine the spatiotemporal trends in fatal and nonfatal collision rates and to identify the individual and contextual factors associated with fatal outcomes . We use confidence intervals geo statistics and generalized additive mixed models corrected for spatial correlation . The collisions records were taken from Bogots Secretariat of Mobility complemented with records provided by non governmental organizations . Our findings indicate that from 2011 to 2017 the fatal bicycling collision rates per bicyclists population have remained constant for females while decreasing 53 for males . Additionally we identified high risk areas located in the west southwest and southeast of the city where the rate of occurrence of fatal events is higher than what occurs in other parts of the city . Finally our results show associated risk factors that differ by sex . Overall we find that fatal collisions are positively associated with factors including collisions with large vehicles the absence of dedicated infrastructure steep terrain and nighttime occurrence . Our findings support policy making and planning efforts to monitor prioritize and implement targeted interventions aimed at improving bicycling safety conditions while accounting for gender differences . | Standardized bicycling collision rates have decreased in Bogot in the last 7 years. Seven main geographic areas of bicycling risk were identified in Bogot. Risk factors associated with bicycling mortality differ by sex. Findings support policy making to implement targeted interventions to improve safety. Methodology based on open data sources to permit replication and monitoring. |
S0001457519313909 | To deal with the increasing number of motor vehicle collisions among older drivers a cognitive test has been introduced to a license renewal procedure for drivers aged 75 years since June 2009 . This might have prompted the reduction or cessation of driving by older drivers . We therefore examined whether older drivers chance of experiencing MVCs as unprotected road users has increased after the test was introduced . Using police reported national data on MVCs from January 2005 through December 2016 we calculated the monthly injury rates among unprotected road users by sex and age group . The ratios of the injury rates of unprotected road users in the three oldest age groups to those aged 7074 years were also calculated . Then we conducted an interrupted time series analysis based on the injury rate ratios to control for extraneous factors affecting MVCs over the study period . There was a significant increase in traffic injuries of unprotected road users at the time the test was introduced among females aged 7584 years and at a later time among males aged 80 years and females aged 85 years . Licensing policies for older drivers should be rigorously evaluated taking into account the safety of older unprotected road users and should be balanced against it . | Stringent licensing for older drivers might prompt premature driving cessation. A cognitive test was added to older drivers license renewal procedure in Japan. Injury risk increased in older unprotected road users afterwards. This risk increase is possibly due to modal shift from driving to non driving. Licensing policies should take into account the safety of unprotected road users. |
S0001457519313922 | Advanced driver assistance systems can effectively support drivers but can also induce unwanted effects in behavior . The present study investigates this adverse behavioral adaptation in adaptive Forward Collision Warning systems . Other than conventional FCW systems that provide warnings based on static Time To Collision thresholds adaptive FCW systems consider the drivers need for support by adjusting warning thresholds according to distraction . A neglected question is how drivers adapt their behavior when they use adaptive FCW systems under realistic conditions i.e . when warnings occur infrequently but system functionality is anticipated . Forty eight participants drove with two different FCW systems while working on a secondary in vehicle task in a driving simulator . During the main part of the experiment no brake events occurred and hence FCW functioning was largely anticipated . Additionally visual system feedback about the drivers distraction state was manipulated between groups . Participants had significantly shorter minimal time headways and TTCs when driving with the adaptive relative to the non adaptive system . Participants with system feedback about distraction state spent generally more time with engaging in the secondary task . These results indicate behavioral adaptation which however is restricted to the task that is specifically supported by the system namely longitudinal control . | Adaptive FCWs adjust warning timing to the drivers current distraction state. Driving simulator study evaluated behavioral adaptation to an adaptive FCW. Adaptive FCW induced adverse behavioral adaptation in longitudinal control. System feedback induced increased secondary task engagement |
S0001457519314083 | Run off road crashes have always been a major concern as this type of crash is usually associated with a considerable number of serious injury and fatal crashes . A substantial portion of ROR fatalities occur in collisions with fixed objects at the roadside . Thus this study seeks to investigate the severity of ROR crashes where elderly drivers aged 65 years or more hit a fixed object . The reason why the present study investigates this issue among older drivers is that comparing to younger drivers this age group of drivers have different psychological and physical features . Because of these differences they are more likely to get injured in ROR types of crashes . This paper applies two types of Artificial Intelligence techniques including hybrid Intelligent Genetic Algorithm and Artificial Neural Network using the crashe information of California in 2012 obtained from Highway Safety Information System database . Although the results showed that the developed ANN outperformed the hybrid Intelligent Genetic Algorithm the hybrid approach was more capable of predicting high severity crashes . This is rooted in the way the hybrid model was trained by taking advantage of the Genetic Algorithm . The results also indicated that the light condition has been the most significant parameter in evaluating the level of severity associated with fixed object crashes among elderly drivers which is followed by the existence of the right and left shoulders . Following these three contributing factors cause of collision Average Annual Daily Traffic number of involved vehicles age road surface condition and gender have been identified as the most important variables in the developed ANN respectively . This helps to identify gaps and improve public safety towards improving the overall highway safety situation of older drivers . | This paper compared Intelligent Genetic Algorithm to ANN in investigating fixed object crashes among elderly drivers. Comparing to ANN Intelligent Genetic Algorithm was more capable of predicting high severity crashes. ANN was more accurate in predicting low severity crashes while it was not able to detect more severe crashes. Too much complexity did not only create over fitting problems but it also increased the model run time significantly. The light condition was identified as the most significant factor followed by the existence of right and left shoulders. |
S0001457519314101 | The aim of the study was to investigate the impact of digital billboards on driving performance and visual attention . The impact of dwell time location and content of digital billboards on driving behaviour was also examined . A 3222 experimental study was undertaken using a laboratory driving simulator and data analysed using factorial four way analysis of variance . A total of 96 participants completed the study ranging in age from 18 to 76 years . On sections of roads containing billboards participants drove at lower mean speeds had more speed variability more variability in lane position more time spent at high risk headway two seconds more time spent at high risk headway 0.25s and had more visual fixations compared to control sections of road with no billboards . Billboards with simple content presented at a long dwell time had the least negative impact on driving outcomes . Billboards with complex content had similar negative effects on driving regardless of dwell time . In addition post mounted roadside billboards with 60s dwell times had the least negative impact on driving . While the presence of digital billboards negatively affected driving performance simple billboard content and longer dwell times were safer . The results of the study will assist in the development of evidence based guidelines for digital billboards . | A simulator study examined the impact of digital billboards on driving performance. The presence of digital billboards negatively affected driving performance. Mean speed speed variability lane position and vehicle headway were affected. Simple billboard content and longer dwell times were safer. |
S0001457519314150 | An imbalanced and small training sample can cause an incident detection model to have a low detection rate and a high false alarm rate . To solve the scarcity of incident samples a novel incident detection framework is proposed based on generative adversarial networks . First spatial and temporal rules are presented to extract variables from traffic data which is followed by the random forest algorithm to rank the importance of variables . Then some new incident samples are generated using GANs . Finally the support vector machine algorithm is applied as the incident detection model . Real traffic data which were collected from a 69.5 mile section of the I 80 highway are used to validate the proposed approach . A total of 140 detectors are installed on the section enabling traffic flow to be measured every 30s . During 14 days 139 incident samples and 946 nonincident samples were extracted from the raw data . Five categories of experiments are designed to evaluate whether the proposed framework can solve the small sample size problem imbalanced sample problem and timeliness problem in the current incident detection system . The experimental results show that our proposed framework can considerably improve the detection rate and reduce the false alarm rate of traffic incident detection . The balance of the dataset can improve the detection rate from 87.48 to 90.68 and reduce the false alarm rate from 12.76 to 7.11 . This paper lends support to further studies on combining GANs with the machine learning model to address the imbalance and small sample size problems related to intelligent transportation systems . | Temporal and spatial rules are developed to select variables from the raw traffic flow data to detect traffic incident. A hybrid traffic incident detection method is proposed to solve the imbalance and small sample size problems in the previous studies. The proposed method has strong real time capability. The new model is evaluated using real word traffic flow and traffic incident data. |
S0001457519314241 | Bicycle wrong way riding is a dangerous and often neglected behavior that engenders threats to traffic safety . Owing to the lack of exposure data the detection of WWR and its relationship with the built environment factors remain unclear . Accordingly this study fills the research gaps by proposing a WWR detection framework based on bike sharing trajectories collected from Chengdu China . Moreover this study adopts Negative Binomial based Additive Decision Tree to investigate the impacts of built environment on WWR frequencies . Results reveal that WWR distribution is unaffected by different periods in a day road length is more influential than road level and road direction in WWR occurrence company bus stop subway station residence and catering facility are primary contributors affecting WWR behavior during peak hours whereas education becomes an emerging influential variable during nonpeak hours and most importantly these variables clearly present non linear effects on the WWR frequencies . Therefore geographically differentiated policies should be adopted for bicycle safety improvement . | We detect bicycle wrong way riding WWR behavior using bike sharing data. Negative Binomial based Additive Decision Trees are developed. The non linear effects of built environment on WWR frequency are captured. WWR is unaffected by different times of day. Residence company and transit facility are the most influential factors. |
S0001457519314320 | Increased cycling uptake can improve population health but barriers include real and perceived risks . Crash risk factors are important to understand in order to improve safety and increase cycling uptake . Many studies of cycling crash risk are based on combining diverse sources of crash and exposure data such as police databases and travel surveys based on shared geography and time . When conflating crash and exposure data from different sources the risk factors that can be quantified are only those variables common to both datasets which tend to be limited to geography and a few general road user characteristics . The Physical Activity through Sustainable Transport Approaches project was a prospective cohort study that collected both crash and exposure data from seven European cities . The goal of this research was to use data from the PASTA project to quantify exposure adjusted crash rates and model adjusted crash risk factors including detailed sociodemographic characteristics attitudes about transportation neighbourhood built environment features and location by city . We used negative binomial regression to model the influence of risk factors independent of exposure . Of the 4 180 cyclists 10.2 reported 535 crashes . We found that overall crash rates were 6.7 times higher in London the city with the highest crash rate relative to rebro the city with the lowest rate . Differences in overall crash rates between cities are driven largely by crashes that did not require medical treatment and that involved motor vehicles . In a parsimonious crash risk model we found higher crash risks for less frequent cyclists men those who perceive cycling to not be well regarded in their neighbourhood and those who live in areas of very high building density . Longitudinal collection of crash and exposure data can provide important insights into individual differences in crash risk . Substantial differences in crash risks between cities neighbourhoods and population groups suggest there is great potential for improvement in cycling safety . | Prospective cohort study of over four thousand cyclists in seven European cities. Longitudinal crash and exposure data enable crash risk analysis at individual level. Crash risks varied substantially by individual neighbourhood factors and city. Participants who cycle more often had lower risk of a crash. Gender social environment and building density were associated with crash risk. |
S0001457519314423 | Identifiable individual level driver licensing and motor vehicle crash data are essential to advancing transportation safety research . However epidemiologic studies using such data are rare which may reflect their inaccessibility . We conducted a legal mapping study to evaluate US state laws regulating access to driver licensing and motor vehicle crash data for use in scientific research . Legal statutes regulating the release of driver licensing and motor vehicle crash data for all 50 US states and the District of Columbia were retrieved . Legal text was evaluated to determine whether these jurisdictions authorize release of identifiable individual level licensing and crash data for use in non governmental research . Thirty six states and D.C. explicitly authorize release of identifiable individual level licensing data to researchers . Only five states and D.C. authorize release of identifiable individual level crash records . No states explicitly prohibit the release of individual level data about licensing records and only three states prohibit release of individual level crash record data meaning that in many states it is ambiguous whether and when releasing such data to researchers is permitted . It is important to understand why licensing data are not used more frequently in transportation safety research given that many state laws permit access for non governmental researchers . Reforming state laws to clarify and increase access to identifiable individual level crash report data is an important priority for transportation safety advocates and researchers . | Review of state legal text to characterize release of driver license and crash data. 37 states and D.C. authorize release of individual level licensing data. Disconnect between authorized release of licensing data and limited use in research. Largely unclear if individual level crash data is accessible in existing statutes. |
S0001457519314435 | Zonal characteristics have been shown to affect biking attractiveness and safety . However previously developed bikeability indices do not account for cyclist vehicle crash risk . This study aims to develop a comprehensive zone based index to represent both biking attractiveness and cyclist crash risk . The developed Bike Composite Index consists of two sub indices representing bike attractiveness and bike safety which are estimated using Bike Kilometers Travelled and cyclist vehicle crash data from 134 traffic analysis zones in the City of Vancouver Canada . The Bike Attractiveness Index is calculated from five factors bike network density centrality and weighted slope as well as land use mix and recreational density . The Bike Safety Index is calculated from bike network coverage continuity and complexity as well as signal density and recreational density . The correlation between the Bike Attractiveness Index and the Bike Safety Index in Vancouver is low supporting the need to account for both biking attractiveness and safety in the composite index . | Develop a comprehensive zone based index to represent both biking attractiveness and cyclist crash risk. Develop Bike Attractiveness Index by employing Bike Kilometers Travelled and Bike Safety Index by employing cyclist crash data. The BAI consists of bike network density centrality weighted slope land use mix and recreational density. The BSI consists of bike network coverage continuity complexity signal density and recreational density. The correlation between the BAI and the BSI in Vancouver Canada is r 0.11. |
S0001457519314460 | Estimation of ones own crossing time is an important process in making road crossing decisions . This study evaluated the pedestrians ability to estimate crossing time in a field experiment . The estimated crossing time was measured by an interval production method and an imagined crossing method . The results showed that while young pedestrians generally had an accurate estimation of their crossing time old pedestrians consistently underestimated the crossing time in both methods especially at a wider road . Whats worse even fast walking can not compensate for the large underestimation . Further analysis showed that although old pedestrians had the declined motor imagery ability and the worse general timing accuracy none of them can account for the inaccuracy of estimation . These findings suggest that underestimation of crossing time may be one of the important reasons for the acknowledged risky road crossing decision making in old pedestrians . It also calls for studies on assistive roadway designs and intervention programs targeting old pedestrians . | Young pedestrians estimated crossing time accurately. Old pedestrians underestimated their crossing time. Fast walking cannot compensate for old pedestrians large underestimation. Declined motor imagery ability cannot account for old pedestrians underestimation. General timing accuracy also cannot account for old pedestrians underestimation. |
S0001457519314587 | Although crashes involving hazardous material vehicles on expressways do not occur frequently compared with other types of vehicles the number of lives lost and social damage is very high when a HAZMAT vehicle involved crash occurs . Therefore it is essential to identify the leading causes of crashes involving HAZMAT vehicles and make specific countermeasures to improve the safety of expressways . This study aims to employ the association rules mining approach to discover the contributory crash risk factors of HAZMAT vehicle involved crashes on expressways . A case study is conducted using crash data obtained from the Korea Expressway Corporation crash database from 2008 to 2017 . ARM was conducted using the Apriori algorithm and a total of 855 interesting rules were generated . With appropriate support confidence and lift values we found hidden patterns in the HAZMAT crash characteristics . The results indicate that HAZMAT vehicle involved crashes are highly associated with male drivers single vehicle involved crashes clear weather conditions daytime and mainline segments . Also we found that HAZMAT tank lorry and cargo truck crashes single vehicle involved crashes and crashes on mainline segments of expressways had independent and unique association rules . The finding from this study demonstrates that ARM is a plausible data mining technique that can be employed to draw relationships between HAZMAT vehicle involved crashes and significant crash risk factors and has the potential of providing more easy to understand results and relevant insights for the safety improvement of expressways . | Main purpose is to identify the critical causes of crashes involving HAZMAT vehicles. Association rules mining ARM was applied to discover the crash risk factors of HAZMAT vehicle involved crashes. With appropriate support confidence and lift values hidden patterns in the HAZMAT crash characteristics were found. HAZMAT vehicle involved crashes are related to male drivers stand alone crashes weather daytime and mainline segments. |
S0001457519314617 | The Rural Intersection Active Warning System is an innovative road safety treatment designed to slow traffic on major approaches to a high risk rural intersection when vehicles are turning or crossing into or out of the side roads thus reducing fatal and serious casualties . A 22 experimental driving simulation study was undertaken which aimed to determine the impact of signage and sign content on drivers instantaneous speed at rural intersections . | The Rural Intersection Activation Warning System RIAWS is designed to slow traffic. It detects vehicles and activates electronic signage on the intersection approaches. A simulator was used to examine the impact of signage type and content on speed. The RIAWS 80km h sign resulted in significantly lower speeds than all other signs. |
S0001457519314745 | This study investigates the impact that delta V the relative change in vehicle velocity pre and post crash has on the severity of motor vehicle collisions . We study injury severity using two metrics for each occupant the number of injuries suffered and the probability of suffering a serious or worse injury . We use a cross sectional set of generally representative MVC data between 2010 and 2015 as a basis for our research . Collision factors that influence the crash environment are combined with the injuries that were suffered in MVCs . The influence of delta V is captured using a mediation analysis whereby delta V acts as the focal point between crash factors and injury outcome . The mediation approach adds to existing research by presenting a detailed view of the relationship between injury severity delta V and other collision factors . We find evidence of competitive mediation wherein a collision factors positive association with injury severity is offset by a negative association with delta V. Neglecting to include delta V in our study would have let the factors association with injury severity go undiscovered . In addition certain collision factors are found to be related to injury severity solely because of delta V while others are found to have a significant impact regardless of delta V. Our results support the multitude of policy recommendations that promote seatbelt use and warn against alcohol impaired driving and support the proliferation of safety enabled vehicles whose technology can mitigate the bodily damage associated with detrimental crash types . | We examine the effect of motor vehicle collision MVC factors on the severity of injuries. Two approaches are considered Log linear Regression and Bayesian Probit Regression. delta V plays a primary role in determining the number of injuries and the probability of suffering an MAIS3 injury. Some crash factors influence injury severity regardless of relative crash velocity delta V . Mediation approach unveils influential links that would have otherwise gone unnoticed. |
S0001457519314757 | Highway rail grade crossings are where a roadway and railway intersect at the same level . Safety at HRGCs has been identified as a high priority concern among transportation agencies but there has been little research on the effects of HRGC geometric parameters on their safety performance . This paper evaluates the effects of HRGC geometric parameters on crash occurrence and severity likelihoods . The competing risk algorithm is selected to simultaneously analyze crash occurrence and severities . Four main HRGC geometric factors along with other contributors are investigated at 3 194 public HRGCs in North Dakota . This study focuses primarily on four geometric features of an HRGC acute crossing angle number of tracks the roadway distance between the HRGC and the signalized intersection and number of highway lanes . Distance to the nearest roadway intersections and highway railway crossing angles are map based calculations drawn from geographic information systems . The findings are all contributors tested in this study including highway characteristics traffic exposures from both railway and highway and the four geometric features significantly affect at least one crash severity level all contributors significantly impact crash frequency except for the distance between crossings and the nearest roadway intersection and geometric parameters long term effects on cumulative probability of crash severity and occurrence over 30 years is also evaluated . Crossings with three main tracks contribute the highest long term crash probabilities . | Survival analysis in highway rail grade crossing safety analysis is introduced. Crossing geometric factors traffic exposure and highway railway characteristics are found significant contributors. Effects on crash frequency and crash severity are researched. Geometric factors long term effects on cumulative probability of crash severity and occurrence over 30 years is evaluated. Crossings with three main tracks contribute the highest long term crash probability. |
S0001457519314794 | Using naturalistic driving data this study explored the prevalence of engagement in secondary tasks whilst driving through intersections and investigated whether drivers manage and self regulate such behaviour in response to variations in roadway and environmental conditions . Video recordings of in vehicle and external scenes were coded for precisely defined categories of secondary tasks and related contextual variables . The findings indicated that nearly one quarter of the total driving time at intersections was spent on secondary activities and that lower engagement occurred within intersections compared to phases immediately upstream or downstream . Drivers were less likely to occupy themselves with secondary tasks when their vehicles were moving than when they were stationary . Elderly drivers showed less inclination to perform secondary tasks than did younger drivers . Lastly drivers tended to perform secondary tasks less frequently at intersections managed by traffic signs than those controlled by traffic lights when they did not have priority compared to when they had priority and in adverse weather conditions compared to fine weather conditions . In conclusion drivers appeared to self regulate secondary task engagement in response to roadway and environmental conditions . Specifically they exercised self regulation by reducing their secondary task engagement when the driving task was more challenging . The findings from this study provide preliminary evidence for targeting the education and training of drivers and media campaigns related to safe driving strategies and managing distractions . | Drivers self regulate their secondary tasks in relation to the driving context. Less secondary task engagement occurred while moving compared to stationary condition. Lower engagement occurred within intersections than phases immediately before or after. Intersection priority and weather condition relate to secondary task engagement. Elderly drivers were less willing to perform secondary tasks than younger drivers. |
S000145751931485X | The Automated Enforcement System has become the most important traffic enforcement system in China . In this study a spatio temporal kernel density estimation model integrating spatio temporal statistics and three dimensional visualization techniques was applied to reveal the spatial and temporal patterns of traffic violation behavior at urban intersections . The multivariate Gaussian kernel function was selected for space and time density estimation as it has been shown to be a good arbitrary probability density function for continuous multivariate data . Because the STKDE model builds a space time cube that adopts different colors of voxels to visualize the density of traffic violations an optimal bandwidth selector that combines unconstrained pilot bandwidth matrices with a data driven method was selected for achieving the best visualization result . The raw AES traffic violation data over 200 weekdays from 69 intersections in the city of Wujiang were empirically analyzed . The results show that the STKDE space time cube made it easier to detect the spatio temporal patterns of traffic violations than did the traditional hotspots map . An interesting finding was that traffic sign violations and traffic marking violations were primarily concentrated not in regular peak hours but during the time period of 14 00 16 00 which indicates that these intersections were the most congested during this period . Primarily the STKDE model identified seven patterns of spatio temporal traffic violation hotspots and coldspots . These results are important because their prediction of temporal trends of traffic violations may help contribute toward the understanding and improvement of intersection safety problems . | A Spatio temporal Kernel Density Estimation is applied to reveal the space and time patterns of traffic violation behavior. The traffic violation data comes from the Automated Enforcement System at 69 intersections. An optimal bandwidth selector that combines unconstrained pilot bandwidth matrices with a data driven method. The STKDE model identified seven patterns of spatio temporal traffic violation hotspots and coldspots. |
S0001457519314988 | It has been widely agreed that it is risky for patients with diabetes to drive during hypoglycemia . However driving during non hypoglycemia may also bring certain safety hazards for some patients with diabetes . Based on previous studies on diabetes related to early aging effect as well as gender differences in health belief and driving behavior we have hypothesized that middle aged male drivers with type 2 diabetes compared with the control healthy ones may experience a decline in driving performance without awareness . And the decline is caused by impaired perceptual and cognitive driving related functions . To verify these hypotheses we recruited 56 non professional male drivers aged between 40 and 60 to perform a simulated car following task and finish behavioral tests of proprioception visual search and working memory abilities during non hypoglycemia . They also reported their hypoglycemia experience and perceived driving skills . We found that the patients had equal confidence in their driving skills but worse driving performance as shown in larger centerline deviation longer brake reaction time and shorter minimum time to collision . Such between group differences in driving performance could be fully mediated by proprioception visual search ability and working memory capacity but not by hypoglycemia experience . Regarding the effect sizes of the mediation the visual search ability played the most important role and then followed the working memory and the proprioception . | Middle aged type 2 diabetic men had no reduced confidence in their driving skills. These diabetic drivers showed deteriorated driving performance in non hypoglycemia. Hypoglycemia experience was not predictive of their driving performance decline. Perceptual cognitive functions can fully explain such driving performance decline. |
S000145751931499X | This study assessed the effect of Chiles 2005 traffic law reform on the rates of road traffic deaths in children aged 014 years adjusting for socioeconomic differences among the regions of the country . Free access sources of official and national information provided the data for every year of the study period and for each of the countrys 13 upper administrative divisions with respect to RTD in child pedestrians and RTD in child passengers and the following control variables the number of road traffic tickets processed investment in road infrastructure poverty income inequality insufficient education unemployment population aged 014 years and prevalence of alcohol consumption in the general population . Interrupted time series analyses using generalized estimating equation methods were conducted to assess the impact of the TLR on the dependents variables . There was a significant interaction between time and Chiles 2005 TLR for a reduction in child pedestrians 0.87 95 confidence interval 0.79 0.96 and passengers RTD trends . In addition in child pedestrians RTD rates were affected by poverty income inequality and unemployment whereas in the case of child passengers poverty and income inequality were significant . Large scale legislative actions can be effective road safety measures if they are aimed at promoting behavioral change in developing countries improving the safety of children on the road . Additionally regional socioeconomic differences are associated with higher RTD rates in this population making this an argument in favor of road safety policies that consider these inequalities . The number of road traffic tickets processed and the investment in road infrastructure were not significant . | Legislative actions that promote behavioral change may reduce road traffic deaths among children aged 014 years. Between region socioeconomic differences requires road safety policies focused on reducing the disparities. Legislative actions and in country socioeconomic differences are relevant to reduce fatal outcomes in the study population. The design of equity based road safety policies promoting behavioral change should be a priority. |
S0001457519315040 | In 2011 a more severe drunk driving law was implemented in China which criminalized driving under the influence of alcohol for the first time and increased penalties for drunk driving . The present study aimed to assess effectiveness of the drunk driving law in China in reducing traffic crashes injuries and mortality . Data used in this study was obtained from the Traffic Management Bureau of the Ministry of Public Security of the Peoples Republic of China . An interrupted time series analysis was conducted to analyze annual data from 2004 to 2017 including the number of road traffic crashes deaths and injuries caused by drunk driving in China . The average annual incidences of crashes mortality and injuries have decreased after the promulgation of drunk driving law in 2011 . In the post intervention period the increased slope for crashes mortality and injury rates were respectively 0.140 to 0.006 0.052 to 0.005 and 0.150 to 0.008 indicating a weaker downward trend of dependent variables . The more stringent drunk driving law is not as effective as expected . Drunk driving is still a severe traffic safety problem to be addressed in China . Both legislation and other prevention programs should be adopted to reduce road traffic injuries caused by drunk driving in China . | The interrupted time series analysis was conducted to evaluate effectiveness of the more severe drunk driving law in China. Drunk driving is still a severe traffic safety problem that needs to be addressed in China. Apart from legal sanctions additional prevention strategies should be taken seriously to improve road safety. |
S0001457519315052 | Forward collision warning and autonomous emergency braking systems are increasingly available and prevent or mitigate collisions by alerting the driver or autonomously braking the vehicle . Threat assessment and decision making algorithms for FCW and AEB aim to find the best compromise for safety by intervening at the right time neither too early potentially upsetting the driver nor too late possibly missing opportunities to avoid the collision . | 94 drivers negotiated an intersection with a pedestrian in a driving simulator. A fractional factorial design tested the effect of 8 factors on driver response. Driver response mainly depended on pedestrian time to arrival and visibility. OpenDS may enable crowdsourcing and favor repeatability across studies. The results help Euro NCAP and design of collision warnings and emergency braking. |
S0001457519315246 | Trucking plays a vital role in economic development in every country especially countries where it serves as the backbone of the economy . The fast growth of economy in Iran as a developing country has also been accompanied by an alarming situation in terms of fatalities in truck involved crashes among the drivers and passengers of the trucks as well as the other vehicles involved . Despite the sizable efforts to investigate the truck involved crashes very little is known about the safety of truck movements in developing countries and about the single truck crashes worldwide . Thus this study aims to uncover significant factors associated with injury severities sustained by truck drivers in single vehicle truck crashes in Iran . The explanatory factors tested in the models include the characteristics of drivers vehicles and roadways . A random threshold random parameters hierarchical ordered probit model is utilized to consider heterogeneity across observations . Several variables turned out to be significant in the model including drivers education advanced braking system deployment presence of curves on roadways and high speed limit . Using those results we propose safety countermeasures in three categories of 1 educational 2 technological and 3 road engineering to mitigate the severity of single vehicle truck crashes . | This study investigated the severity of single vehicle truck crashes occurred in Iran. This study highlighted the contextual differences in the severity of single vehicle truck crashes. This study used a random thresholds random parameters hierarchical ordered probit HOPIT model. According to the results several safety countermeasures are proposed to mitigate the severity of single vehicle truck crashes. |
S0001457519315258 | This paper describes a study that applies the Poisson Tweedie distribution in developing crash frequency models . The Poisson Tweedie distribution offers a unified framework to model overdispersed underdispersed zero inflated spatial and longitudinal count data as well as multiple response variables of similar or mixed types . The form of its variance function is simple and can be specified as the mean added to the product of dispersion and mean raised to the power | Given a flexible framework for count data regression the Poisson Tweedie distribution was used to model crash frequency. A series of models with fixed and varying dispersion were developed under different values of power parameter in variance. The performance of a model varied by how the dispersion parameter was formulated. The dispersion parameter values were found to be smaller in models fitted with higher value of the power parameter. The variation in expected crash frequency and site ranking linked to different dispersion and power parameters was examined. |
S0001457519315313 | In May 2014 the Dominican Republic introduced the 911 emergency response system in Santo Domingo . Before its introduction more than 40 phone numbers were available to report emergencies . The objective of this work is to assess whether this new emergency response system was effective in reducing traffic fatalities . Weekly numbers of traffic fatalities per population and per vehicle fleet from January 2013 to December 2015 were obtained from the Ministry of Health and the National Institute of Statistics . A hybrid time series difference in difference analysis using multivariable negative binomial regression models were used to compare trends in rates of traffic fatalities in Santo Domingo to La Romana and Santiago before and after the introduction of the 911 ERS . Estimates from negative binomial models suggest that the introduction of the 911 ERS in Santo Domingo relative to Santiago La Romana was associated with a 17 reduction in the Incidence Rate Ratio of traffic fatalities per 1 000 000 population 0.67 1.03 and with a 20 reduction in the IRR of weekly traffic fatalities per 1 000 000 vehicle fleet . Our findings suggest that transitioning from multiple to one unique emergency phone number should be considered more attentively . Furthermore the case of the Dominican Republic calls for more theoretical and methodological research to understand how to assess these road safety policies more accurately . Since various studies suggest that 911 ERS mature in the long run how these systems evolve over time and other related variables should be carefully considered . | Studies in low and middle income countries focusing on emergency response system ERS and traffic fatalities have shown considerable discrepancies. In May 2014 the Dominican Republic introduced the 911 ERS to reduce among other challenges traffic mortalities in Santo Domingo. The introduction of the 911 ERS in this city was not associated with important reductions in traffic fatality rates. In the Dominican Republic the efficacy of the 911 ERS to address the burden of road traffic fatality requires further improvements. |
S0001457519315398 | While computer vision techniques and big data of street level imagery are getting increasing attention a black box model of deep learning hinders the active application of these techniques to the field of traffic safety research . To address this issue we presented a semantic scene labeling approach that leverages wide coverage street level imagery for the purpose of exploring the association between built environment characteristics and perceived crash risk at 533 intersections . The environmental attributes were measured at eye level using scene segmentation and object detection algorithms and they were classified as one of four intersection typologies using the k means clustering method . Data on perceived crash risk were collected from a questionnaire conducted on 799 children 10 to 12 years old . Our results showed that environmental features derived from deep learning algorithms were significantly associated with perceived crash risk among school aged children . The results have revealed that some of the intersection characteristics including the proportional area of sky and roadway were significantly associated with the perceived crash risk among school aged children . In particular road width had dominant influence on risk perception . The findings provide information useful to providing appropriate and proactive interventions that may reduce the risk of crashes at intersections . | The study examined influence of built environment on perceived crash risk. A semantic scene labeling approach was applied to street view imagery. Visual openness at the intersection reduced risk perception. The proportional area of roadway showed dominant influence on risk perception |
S0001457519315404 | In this study a virtual reality pedestrian simulation method was used to evaluate the risks to pedestrians crossing streets in a traffic system with driving rules that were unfamiliar to them . Pedestrians from mainland China system and Hong Kong system were studied . Significant differences were observed between pedestrians from the different locations in terms of the direction in which the pedestrians habitually first looked before crossing . When exposed to an unfamiliar driving rule the odds of participants from mainland China making an error in their looking behavior were 2.93 times those when exposed to a familiar driving rule . Road markings and traffic sound did not improve these participants looking behavior . The results also show a negative correlation between inattentive looking behavior and time to collision as these errors lead to a shorter time to collision and increased the risk to pedestrians . The results of this study confirmed the risks for pedestrians traveling to places with unfamiliar driving rules and confirmed the existence of habitual looking behavior and therefore provide evidence of the need for future studies to improve this problem . These may help decision makers take the risks of pedestrians from different driving rules into consideration in future traffic policymaking or traffic facility improvements . The use of a VR simulation based approach in this study provided a safe and controllable way to trial interventions and potential improvements without risking injury to participants and thus may also be used for similar future studies . | Pedestrian experiment was conducted with virtual reality simulation in a safe repeatable and controllable way. Significant differences exist on pedestrians habitual behavior between mainland China ML and Hong Kong HK . ML pedestrians show more inattentive looking behaviors under the unfamiliar driving rule. Significant relationships exist between inattentive looking behaviors and time to collision. To reduce risks under unfamiliar driving rules more effective facilities should be considered. |
S0001457519315507 | Snowy weather is consistently considered as a hazardous factor due to its potential leading to severe fatal crashes . A seven year crash dataset including rural highway single vehicle crashes from 2010 to 2016 in Washington State is applied in the present study . Pseudo elasticity analysis is conducted to investigate significant impact factors and the temporal stability of model specifications is tested via a likelihood ratio test . The proposed model based on the seven year dataset is able to capture the individual specific heterogeneity across crash records for four significant factors i.e . surface ice male and airbag combine deployment for minor injury and male for serious injury and fatality . Their estimated parameters were found to be normal distribution instead of fixed value over the observations . Other significant impact factors with fixed effects are inroad object animal overturn surface wet surface snow unusual horizontal design medium and high speed limits driver age impaired condition no belt usage vehicle type airbag deployment . Especially when compared to significant factors for crashes under other weather conditions male indicator and impaired condition show significant higher effects in snow related crashes . The results of temporal stability test show that the model specification is generally not temporally stable for driver injury severity model based on the years of crash data that were used especially for longer period . Models that allow the explanatory variables to track temporal heterogeneity are of great interest and can be explored in future research . | This paper examines driver injury severities in snow related single vehicle crashes. Mixed logit model is developed in different years. Pseudo elasticity analysis approach is applied. The results show temporal instability in model specification. The study provides insights on casualties and injury prevention. |
S0001457519315519 | How crashes translate into physical injuries remains controversial . Previous studies recommended a predictor Delta V to describe the crash consequences in terms of mass and impact speed of vehicles in crashes . This study adopts a new factor energy loss based vehicular injury severity to explain the effects of the energy absorption of two vehicles in a collision . This calibrated variable which is fitted with regression based and machine learning models is compared with the widely used Delta V predictor . A multivariate ordered logistic regression with multiple classes is then estimated . The results align with the observation that heavy vehicles are more likely to have inherent protection and rigid structures especially in the side direction and so suffer less impact . | An in depth analysis of the severity of crashes is needed to mitigate traffic crashes. Regression models are to analyze the relationship between injury and crash mechanisms. Occupants receive less impact from collisions by protective structures and high stiffness. The mass ratio of vehicles affects energy absorption especially in lateral structures. |
S0001457519315593 | Speeding is considered as one of the most significant contributing factors to severe traffic crashes . Understanding the associations between trip driving roadways features and speeding behavior is crucial for both researchers and practitioners . This research utilized naturalistic driving data collected by the Safety Pilot Model Deployment program and roadway features from a road inventory dataset Highway Performance Monitoring System provided by the United States Department of Transportation to investigate the hidden rules that associated trip driving roadway features with speeding behavior . A classification based association algorithm was adopted to explore the hidden rules from two perspectives of speeding speeding duration and speeding pattern . Results indicate that the combinations of longer trips driving on the roadways with a relatively higher functional class are highly associated with longer speeding events . The moderate speeding events are found highly associated with the combination of driving on roadways with lower functional class absence of a median and relatively short trip time . The research also found the combinations of driving on roadways with relatively lower functional class experienced congestion before a speeding event and the presence of a median is a leading cause that triggers a higher speeding pattern . Furthermore the moderate speeding pattern is associated with the combinations of factors like experiencing congestion before a speed event driving on roadways with higher functional class and a relatively shorter trip . The findings can help practitioners understand the composite effect of these factors more comprehensively and provide corresponding countermeasures to mitigate the negative consequences of speeding wherever possible . These can also help in calibrating driver behavior parameters for transportation related simulation tools . | Understand speeding behavior from two perspectives speeding pattern and speeding duration. Longer trips driving on the roadway with higher functional class are associated with longer speeding events. Short trips absence of median and lower functional class roadways are associate with moderate speeding events. Drive on roadways with low functional class experienced congestion and presence of median leads to a higher speeding pattern. Drive on roadways with higher functional class experienced congestion and short trips trigger a moderate speeding pattern. |
S0001457519315623 | Crosswalk markings are a type of facility installed at the vehicle pedestrian interaction locations and the function is to warn drivers to watch out for pedestrians crossing the street and improve safety for pedestrians . In Beijing a type of new designed crosswalk markings in China was installed . However evaluating the effectiveness of this type of crosswalk markings was not conducted . Accordingly the objective of this paper is to evaluate the effectiveness of this type of new designed crosswalk markings . During the evaluation process the vehicle pedestrian interaction was considered standard crosswalk markings in China were taken as a control group . In addition empirical data were collected from a driving simulator and nine evaluating indicators representing vehicle operating data drivers maneuvering data and drivers subjective evaluation were proposed . In order to combine nine indicators a Technique for Order of Preference by Similarity to Ideal Solution method was used in this study to achieve the premium degrees of these two types of crosswalk markings . The evaluation result showed that for intersections with high or low pedestrian flow the comprehensive effectiveness and influences on drivers driving behaviors with presence of NCMC were better than those with presence of SCMC no matter where vehicle pedestrian interactions occurred . For intersections with no pedestrians the comprehensive effectiveness and influences on drivers driving behaviors with presence of NCMC were worse than those with presence of SCMC no matter where vehicle pedestrian interaction occurred . These results may provide references for facility installing and future development of standards . | When and where vehicle pedestrian interaction occurs is taken into account in the evaluation process. Used TOPSIS to evaluate the effectiveness of NCMC and SCMC. For intersections with the high or low pedestrian flow the effectiveness of NCMC is better than those of SCMC. For intersections with no pedestrians the effectiveness of NCMC were worse than those of SCMC. |
S0001457519315659 | A passing maneuver allows drivers to maintain their desired speed on two lane highways . However it entails a high risk of collision with vehicles travelling in the opposite direction . Investigating drivers behavior while performing passing maneuvers could provide helpful information on the factors that influence this process . Driving simulators have become important tools for driving behavior research studies as they are safe facilitate the controlled use of experimental variables and generate detailed output data . It remains to be seen whether simulator results can be considered representative of real life driving conditions . With respect to passing maneuvers no study has made a comprehensive and direct comparison between drivers passing behavior in the field and driver behavior observed in a simulated environment . | The validity of the driving simulator for studies of passing behavior was investigated. Significant similarities in gap acceptance and perception reaction time behavior in the simulator and in the field were found. Level of risk taking by drivers using he driving simulator was similar to that in the field. Although drivers passed at slower speeds in the simulator than in the field the distribution shapes were similar. Iranian and Italian drivers showed similar passing behaviors. |
S0001457519315738 | This paper employed a high fidelity driving simulator to investigate the impacts of the Wyoming Department of Transportation Connected Vehicle Pilots Traveler Information Messages on drivers speed selection and the safety benefits of their speed harmonization . Three driving simulator experiment scenarios were developed to simulate the typical traffic and weather conditions on the rural Interstate 80 in Wyoming . A total of 25 professional drivers from the WYDOT and trucking industry were recruited to participate in the driving simulator experiment . Participants instantaneous speeds at various locations were collected to reveal the effects of CV TIMs on their speed selection . The results showed that average speed profiles under CV scenarios were generally lower than under baseline scenarios particularly for winter conditions . The variance of speed under CV scenarios was found to be significantly lower than the baseline scenarios indicating that CV TIMs have the potential to harmonize the variations in speed . In addition for the work zone driving simulator experiment this research revealed that the mean time to collision under baseline scenario is approximately 40 lower than CV scenario and the mean deceleration to avoid a crash under baseline scenario is approximately 19.3 higher than CV scenario . These findings suggest that CV TIMs can reduce the risk of crashes . Research findings would provide the WYDOT with early insights into the effectiveness of CV TIMs which could assist with developing more efficient transportation management strategies under adverse weather conditions . | Effectiveness of CV Traveler Information Messages on drivers speed behavior was assessed. High Fidelity driving simulator experiments were developed to simulate various real world traffic scenarios. The average speed and speed variance under CV scenarios were generally lower than under baseline scenarios. Time to Collision TTC under the baseline scenario is approximately 40 lower than the CV scenario. Deceleration to Avoid a Crash DRAC under the baseline scenario is approximately 19.3 higher than the CV scenario. |
S0001457519315751 | Lane change has been recognized as a challenging driving maneuver and a significant component of traffic safety research . Developing a real time continuous lane change detection system can assist drivers to perform and deal with complex driving tasks or provide assistance when it is needed the most . This study proposed trajectory level lane change detection models based on features from vehicle kinematics machine vision roadway characteristics and driver demographics under different weather conditions . To develop the models the SHRP2 Naturalistic Driving Study and Roadway Information Database datasets were utilized . Initially descriptive statistics were utilized to investigate the lane change behavior which revealed significant differences among different weather conditions for most of the parameters . Six data fusion categories were introduced for the first time considering different data availability . In order to select relevant features in each category Boruta a wrapper based algorithm was employed . The lane change detection models were trained validated and comparatively evaluated using four Machine Learning algorithms including Random Forest Support Vector Machine Artificial Neural Network and eXtrem Gradient Boosting . The results revealed that the highest overall detection accuracy was found to be 95.9 using the XGBoost model when all the features were included in the model . Moreover the highest overall detection accuracy of 81.9 using the RF model was achieved considering only vehicle kinematics based features indicating that the proposed model could be utilized when other data are not available . Furthermore the analysis of the impact of weather conditions on lane change detection suggested that incorporating weather could improve the accuracy of lane change detection . In addition the analysis of early lane change detection indicated that the proposed algorithm could predict the lane changes within 5s before the vehicles cross the lane line . The developed detection models could be used to monitor and control driver behavior in a Cooperative Automated Vehicle environment . | Lane change has a substantial impact on roadway safety. More comprehensive SHRP2 Naturalistic Driving Study datasets were utilized. Six data fusion categories were introduced considering different data availability. Different Machine Learning approaches to detect lane change maneuvers were explored. Findings could be used to monitor driver behavior in Connected Vehicle environments. |
S0001457519315805 | Most of the previous studies that investigated the factors increasing the severity of rear end collisions were based on analyzing collision reports from multiple years and combining them into a single dataset for analysis . Analyzing pooled data from multiple years carries the risk of introducing aggregation bias in the analysis . Those aggregated models might be structurally unstable and the significance of the risk factors identified using those aggregated models might change over time due to the ongoing changes in vehicle technologies law enforcement technologies and drivers attitudes . This study demonstrates the importance of testing the temporal stability of pooled data by utilizing logistic regression modeling to analyze all rear end collisions that occurred in North Carolina for the period from January 1 2004 to December 31 2015 . Separate models were developed for each year to model injury severity of striking and struck drivers . The year wise models were compared together to identify the most temporally stable factors and it was found that older and female drivers are usually more severely injured but they do not increase injury severity of the drivers they collide with . It was also found that compared to other light duty vehicles passenger cars are usually associated with increased injury severity to their drivers and reduced injury severity to the drivers of the vehicles they collide with . The increased age of a vehicle was found to increase the injury severity of its driver as well as the driver of the vehicle it collides with . Dark conditions were found to increase drivers injury severity but adverse weather conditions have no similar effect . For comparison aggregated models were also developed by pooling data from all analysis years and were found to return significant factors that were found by the year wise models to be temporally unstable . Chow tests were performed on the data and it was found that pooling data for four years or more generally returned structurally unstable models . | Logistic regression is used to identify factors affecting injury severity in each year for striking and struck drivers. Year models were compared together and compared with pooled models to identify temporally stable factors. Temporal instability found when pooling data for four years or more. Female drivers either striking or struck are consistently more prone to severe injuries. Drivers own age increases injury severity of the driver with no effect on the colliding driver. |
S0001457519315866 | Speeding behaviour is known to influence crash risk among alcohol impaired drivers but this relationship is scarcely explored . The present study investigated the effects of different Blood Alcohol Concentrations levels on driving performance with respect to mean speed of drivers and their ability to avoid crashes during sudden events while driving . Eighty two drivers participated in the simulation driving experiment at four BAC levels in rural and urban driving scenarios . Two sudden events in the perpendicular direction of traffic were designed to evaluate the crash probabilities in both the driving scenarios . Generalized linear mixed models were developed to analyse the effects of BAC levels and driver attributes on mean speeds and crash probabilities . Results for mean speed showed that compared to sober state drivers drove 3.5 kmph 5.76 kmph and 8.78 kmph faster at 0.03 0.05 and 0.08 BAC respectively in the rural environment and this increment was 3.6 kmph 3.69 kmph and 4.13 kmph in the urban environment . The model results for crash probabilities revealed that 0.03 0.05 and 0.08 BAC levels increased the crash probabilities by 1.9 times 2 times and 3 times in case of the rural environment and 2 times 2.3 times and 3.5 times respectively in the urban driving environment . | Driving simulator experiments were conducted at 0 0.03 0.05 and 0.08 BACs. Eighty two Indian drivers participated in the experimental study. Effects of alcohol on speeding behaviour and accident probabilities were analysed. Significant increments in driving speed were observed with increasing BACs. Accident probabilities were higher in urban settings compared to rural for all BACs. |
S0001457519315933 | The objective of this research is to exploit high resolution driving behavior data collected via sensors of smartphones from 303 drivers in order to examine driver behavior at road segment and junction level . These sensor data are combined with traffic and road geometry characteristics and subsequently depicted spatially using Geographical Information System software . Events of harsh driver behavior were mapped to delimited segments and junctions of two urban expressways in Athens Greece . For the analysis two multiple linear regression models and two log linear regression models were developed . Results indicate that in road segments there is an increase in the number of harsh events if average traffic flow per lane increases in the respective areas . Furthermore as the average occupancy increases in junctions there is an increase in harsh accelerations and as the average speed increases more harsh deceleration events occur . It is evident that traffic characteristics have the most statistically significant impact on the frequency of harsh events compared to factors related to road geometry and driver behavior . | This paper exploits high resolution driving behavior data obtained from smartphones. The analysis is augmented by traffic data at the time of harsh behavior event. Harsh event frequencies are examined in segments junctions of urban expressways. In road segments harsh events increase with traffic volume increases. In junctions harsh accelerations brakings increase with occupancy speed increases. |
S0001457519316057 | Most previous studies investigate the safety effects of a single speed camera ignoring the potential impacts from adjacent speed cameras . The mutual influence between two or even more adjacent speed cameras is a relevant attribute worth taking into account when evaluating the safety impacts of speed cameras . This paper investigates the safety effects of two or more speed cameras observed within a specific radius which are defined as multiple speed cameras . A total of 464 speed cameras at treated sites and 3119 control sites are observed and related to road traffic accident data from 1999 to 2007 . The effects of multiple speed cameras are evaluated using pairwise comparisons between treatment units with different doses based on the propensity score methods . The spatial effect of multiple speed cameras is investigated by testing various radii . There are two major findings in this study . First sites with multiple speed cameras perform better in reducing the absolute number of road accidents than those with a single camera . Second speed camera sites are found to be most effective with a radius of 200m . For a radius of 200m and 300m the reduction in the personal injury collisions by multiple speed cameras are 21.4 and 13.2 more than a single camera . Our results also suggest that multiple speed cameras are effective within a small radius . | Propensity score method is applied to analyze how multiple speed cameras affect road safety. Doubly robust estimation is conducted by using a pairwise comparison approach. Sites with more speed cameras perform better in reducing casualties. Multiple speed cameras are most effective with a radius of 200m. |
S0001457519316069 | Traffic congestion is more likely to lead to aggressive driving behavior that is associated with increased crash risks . Previous studies mainly focus on driving behavior during congestion when studying congestion effects . However the negative effects of congestion on driving behavior may also affect drivers post congestion driving . To fill this research gap this study examined the influence of traffic congestion on driver behavior on the post congestion roads . Twenty five subjects participated in a driving simulation study . They were asked to complete two trials corresponding to post congestion and non congestion conditions respectively . Driver behavior quantified by driving performance measures eye movement measures and electroencephalogram measures was compared between the two conditions . Ten features were selected from the measures with statistical significance . The selected features were integrated to characterize drivers response patterns using a hierarchical clustering method . The results showed that driver behavior in post congestion situations became more aggressive more focused in the forward area but less focused in the dashboard area and was associated with lower power of the band in the temporal brain region . The clustering results showed more aggressive and lack of aware response patterns while driving in post congestion situations . This study revealed that traffic congestion negatively affected driver behavior on the post congestion roads . Practical implications for driving safety education was discussed based on the findings from the present study . | Congestion effects on driver behavior in post congestion driving were examined. Congestion negatively affected driver behavior on the post congestion roads. More aggressive driving patterns were observed in post congestion driving. Drivers became less focused on the dashboard area in post congestion driving. Findings here highlight the importance of attending to safe driving after congestion. |
S0001457519316112 | This study estimates how many additional cyclist accidents injuries or fatalities are avoided or mitigated by adding a system which increases braking levels the Torricelli Vacuum Emergency Brake to a state of the art Automated Emergency Braking system . To obtain a realistic state of the art AEB system the AEB parameter settings were defined to fulfil but not exceed the performance necessary to achieve a full score in the European New Car Assessment Program . The systems are simulated in a simple but realistic simulation model in MATLAB with varying brake deceleration and sensor field of view . | Injury risk curves were created from 2662 passenger car to cyclist accidents. Safety benefits were estimated from 1340simulated car to cyclist accidents. Vacuum Emergency Braking VEB prevents 59 of cyclist accidents. VEB also prevents 67 of severe injuries and 86 of the fatalities. VEB is substantially more effective than standard Automated Emergency Braking. |
S0001457519316173 | The study analyses the Human Machine Interface of a driver assistance system for cooperative driving such as merging or turning left situations . Three versions of the HMI are varied as independent variables within subjects . Two versions displayed in the instrument cluster focus either on a dynamic or a static illustration of the current status of the system . The third HMI developed in a preliminary study serves as benchmark to compare the cluster based HMIs . The benchmark HMI uses the same status messages and highlights the partner directly in the environment by augmented reality elements . The results of the present study show that the Benchmark best supported cooperative behavior . Both versions of the HMI located in the instrument cluster also support cooperative behavior and are accepted by the drivers . However more glances are shifted from the relevant area in the driving scenario towards the cluster compared to the Benchmark HMI . With the static version the participants felt more distracted compared to the dynamic HMI . In conclusion as long as it is not technically possible to display the partner directly in the environment a dynamic display in cooperation situations is a good alternative . | A cooperative driving system for manual and automated driving is evaluated. The form of information presentation dynamic vs. static is investigated. Both versions of the HMI support cooperative behavior and are accepted. With the static HMI the participants felt more distracted than the dynamic one. |
S0001457519316197 | Distracted and impaired driving is a key contributing factor in crashes leading to about 35 of all transportation related deaths in recent years . Along these lines cognitive issues like inattentiveness can further increase the chances of crash involvement . Despite its prevalence and importance little is known about how the duration of these distractions is associated with critical events such as crashes or near crashes . With new sensors and increasing computational resources it is possible to monitor drivers vehicle performance and roadway features to extract useful information e.g . eyes off the road indicating distraction and inattention . Using high resolution microscopic SHRP2 naturalistic driving data this study conducts in depth analysis of both impairments and distractions . The data has more than 2 million seconds of observations in 7394 baselines 1228 near crashes and 617 crashes . The event data was processed and linked with driver behavior and roadway factors . The intervals of distracted driving during the period of observation were extracted next rigorous fixed and random parameter logistic regression models of crash near crash risk were estimated . The results reveal that alcohol and drug impairment is associated with a substantial increase in crash near crash event involvement of 34 and the highest correlations with crash risk include duration of distraction through dialing on a cellphone texting while driving and reaching for an object . Using detailed pre crash data from instrumented vehicles the study contributes by quantifying crash risk vis vis detailed driving impairment and information on secondary task involvement and discusses the implications of the results . | How are duration of distraction and impairment related to safety critical events. Classify secondary tasks performed by drivers prior to crash or near crash. Longer distraction durations especially by cellphones substantially increase crash risk. Alcohol and drug impairment also substantially increase crash risk. |
S0001457519316252 | A rear end crash is a widely studied type of road accident . The road area at the crash scene is a factor that significantly affects the crash severity from rear end collisions . These road areas may be classified as urban or rural and evince obvious differences such as speed limits number of intersections vehicle types etc . However no study comparing rear end crashes occurring in urban and rural areas has yet been conducted . Therefore the present investigation focused on the comparison of diverse factors affecting the likelihood of rear end crash severities in the two types of roadways . Additionally hierarchical logistic models grounded in a spatial basis concept were applied by determining varying parameter estimations with regard to road segments . Additionally the study compared coefficients with multilevel correlation model and those without multilevel correlation . Four models were established as a result . The data used for the study pertained to rear end crashes occurring on Thai highways between 2011 and 2015 . The results of the data analysis revealed that the model parameters for both urban and rural areas are in the same direction with the larger number of significant parameter values present in the rural rear end crash model . The significant variables in both the urban and rural road segment models are the seat belt use and the time of the incident . To conclude the present study is useful because it provides another perspective of rear end crashes to encourage policy makers to apply decisions that favor rules that assure safety . | The previous literature clearly shows that rural and urban roadway are different. A hierarchical model comprising 2 sub models incorporating the random intercept model and the random parameters model. Significant variables in both the urban and rural models are the seat belt use and the time. This study focuses on obtaining new knowledge to establish guidelines for reducing the rate of fatal rear end crashes. |
S0001457519316264 | Koreas elderly population is growing rapidly as is attention to elderly pedestrian safety . Despite a consensus that the elderly are vulnerable to pedestrian safety issues our understanding of the determinants of elderly pedestrian crashes is limited . This study explores which attributes of the built environment affect the risk of pedestrian accidents among the elderly particularly with respect to injury severity in Seoul Korea . We compare the impacts of various determinants on pedestrian crashes to specify how the associations between various built environments and pedestrian accidents differ by pedestrian age . We also examine how the associations vary by neighborhood economic attributes . Our findings provide policy implications for identifying various attributes of the built environment that increase the risk of elderly pedestrian crashes and improving the safety of elderly pedestrian by neighborhood economic status . | Examining effects of built environments on elderly pedestrian crashes. Comparing impacts of built environments between all age and elderly groups. Exploring how the impacts vary across neighborhoods stratified by housing price. Using a negative binomial regression with a spatial autocorrelation correction. Impacts of built environments vary by pedestrian age and area characteristics. |
S0001457519316306 | The threat of application of legal sanctions remains the prominent approach to reduce the prevalence of drink driving in a vast array of motoring jurisdictions . However ongoing questions remain regarding the extent that such mechanisms impact upon offending behaviours the deleterious effect alcohol consumption has on decisions to drink and drive and how best to operationalise the concept of drink driving to enhance the accurate measurement of the dependent variable . This paper reports on an examination of 773 Queensland motorists perceptions of both legal and non legal drink driving sanctions in order to gauge the deterrent impact upon a range of measures of drink driving the driver thinking they are over the limit the driver knowing they are over the limit attempts to evade random breath testing and intentions to re offend . The sample completed an online or paper version of the questionnaire . The majority of participants reported never engaging in possible or acknowledged drink driving events although a considerable proportion of the sample reported engaging in possible or acknowledged drink driving and attempting to evade RBT events as well as possible intentions to drink and drive in the future . Males were more likely to report such events . Perceptions of both legal sanctions as well as non legal sanctions were relatively high and consistent with previous research . Interestingly non legal sanctions were reported as stronger deterrents than legal sanctions . However multivariate analysis revealed that legal deterrents had limited utility predicting offending behaviours but rather demographic characteristics as well as risky drinking behaviour were better predictors . In regards to intentions to offend a past conviction for drink driving was also a predictor of re offending . These results highlight the ongoing challenges of addressing the problem of drink driving and that some motorists have entrenched behaviour and or make the decision to drink and drive before they are under the influence of alcohol . | Various measures used to operationalise drink driving were examined. Perceptions of both legal and non legal sanctions for drink driving were high. Non legal sanctions were a larger deterrent for drink driving than legal sanctions. Past drink driving conviction was a predictor of re offending. Age gender and risky drinking behaviours were drink driving predictors. |
S0001457519316380 | This study aimed at modeling the Response Time and Total Braking Time of drivers under Partial Sleep Deprivation . Fifty male participants drove the driving simulator in three experimental conditions two test sessions and a baseline . The two test sessions were conducted after one and two nights of PSD respectively . Sleep reduction was recorded using a wrist worn Actiwatch . The baseline session was conducted after full rest . The order of test sessions and baseline was randomized . Each test included two hazard events 1 pedestrians crossing a road and 2 parked vehicles merging into a roadway . Karolinska Sleepiness Scale and Sleepiness Symptoms Questionnaire ratings were also recorded during each drive . Four separate models using parametric accelerated failure time with Weibull distribution were developed for RT and TBT in the two events . The models were chosen with clustered heterogeneity to account for intra group heterogeneity due to repeated measures across tests . In the case of pedestrians crossing event RT increased by 10 in the first test session and no significant effect observed on RT in the second test session . The overall TBT reduced by 25 and 28 during the first and second PSD sessions respectively . In the case of vehicle merging event both response time and total braking time delayed by 44 and 17 respectively after PSD . Other factors such as age experience work rest hours KSS and SSQ rating often exercising approaching speed and braking force were also found significant in the analysis . The parametric AFT approach adopted in this study showed the change in response time and total braking time concerning the type of hazard scenario and partial sleep deprivation . | Initial response time delayed by 25 44 with partial sleep loss. Drivers with habitual sleeprecommended 7 8h are at higher risks of sleep loss impairments. Driving experience does not compensate for sleep loss effects in unfamiliar hazard scenarios. Total braking time reduced in pedestrian event and increased in vehicle merging event. |
S0001457519316422 | Providing drivers with real time weather information and driving assistance during adverse weather including fog is crucial for safe driving . The primary focus of this study was to develop an affordable in vehicle fog detection method which will provide accurate trajectory level weather information in real time . The study used the SHRP2 Naturalistic Driving Study video data and utilized several promising Deep Learning techniques including Deep Neural Network Recurrent Neural Network Long Short Term Memory and Convolutional Neural Network . Python programming on the TensorFlow Machine Learning library has been used for training the Deep Learning models . The analysis was done on a dataset consisted of three weather conditions including clear distant fog and near fog . During the training process two optimizers including Adam and Gradient Descent have been used . While the overall prediction accuracy of the DNN RNN LSTM and CNN using the Gradient Descent optimizer were found to be around 85 77 84 and 97 respectively much improved overall prediction accuracy of 88 91 93 and 98 for the DNN RNN LSTM and CNN respectively were observed considering the Adam optimizer . The proposed fog detection method requires only a single video camera to detect weather conditions and therefore can be an inexpensive option to be fitted in maintenance vehicles to collect trajectory level weather information in real time for expanding as well as updating weather based Variable Speed Limit systems and Advanced Traveler Information Systems . | Primary focus of this study was to develop an in vehicle fog detection method. Videos from the SHRP2 Naturalistic Driving Study dataset were used. Deep learning using TensorFlow Machine Learning library were utilized. The proposed deep learning models provided impressive weather detection accuracy. The proposed method can be used to develop connected weather based VSL algorithm. |
S0001457519316483 | The rapid development of expressways has led to an increasing number of place names that must be displayed on road guide signs . As a result multi board guide signs have been increasingly set up on expressways . The main aim of this study was to analyze the effect of the directional road sign displayed on multi and single board signs on driver mental workload and behavior . 32 participants including 16 females participated in the experiment and completed 3 driving simulation scenes . The setting of each scene sign board was different 1 board 2 boards and 3 boards . The driver needed to reach the designated destination according to the guidance of the road signs . Eye tracker was used to measure the fixation saccade and electroencephalogram was used to measure the alpha band absolute power in different signage scenarios . There are two major findings of the study . First when the number of place names is less than or equal to 7 the multi board sign generates more mental workload than the single board sign does . The alpha band power of the driver s frontal area under the multiple boards is lower and affects driving performance . Second when the number of place names is more than 7 there is no significant difference in the effect on mental workload whether multi or single board sign is used . However compared to the single board sign drivers in the case of multi board sign are likely to reduce the fixation duration and increase the number of saccades . The results suggest that it is not necessary to use multi board signs when the number of place names is less than 7 . These findings provide more safety considerations for the setting of multi board guide signs in the future . | From the perspective of driver s mental workload the impact of the multi board guide signs on traffic safety is studied. 32 participants drove on three simulated scenes guided by single board and multi board road signs with different number of place names as 5 7 9 and 11. The multi board signs generate more mental workload than the single board sign as result of harsh driving performance. Drivers are likely to reduce the fixation duration and increase the number of saccades on the multi board signs. |
S0001457519316525 | Mobile phone distracted driving is a major risk factor for crashes . However this behaviour has been increasing in recent years . Effective enforcement of mobile phone bans while driving faces several obstacles as such it is important to consider additional countermeasures . Applications designed to prevent distracted driving are a promising solution yet more research is needed that examines their effectiveness in reducing dangerous phone use while driving behaviours . Additionally these applications are voluntary in nature therefore an understanding of drivers perceptions of the applications is necessary to determine how to improve uptake . A mixed methods design was utilised to examine these factors in a comprehensive manner . A total of 40 participants used the smartphone application Do Not Disturb While Driving for iOS phone operating systems or Android Auto for Android phone operating systems for approximately one week and completed three diary entries reporting on their experience . Two questionnaires that examined phone use while driving behaviours were also administered to participants one before and one after completing the study . The quantitative results found that engagement in 1 visual manual 2 cognitive auditory and 3 music mobile phone interactions significantly decreased while using the application . Distraction engagement and mental workload while driving also significantly decreased while using the application . The qualitative results identified a number of areas of improvement that need to be addressed e.g . activation of the application and Bluetooth connection reliability . The features that required improvement presented an obstacle for effective use of the applications and in some cases resulted in drivers deciding to stop using the application . Positive perceptions of the application were associated with the experiences of the application functioning appropriately and activating automatically . These results show that applications designed for voluntary use to prevent mobile phone distracted driving are a promising countermeasure although current applications require several improvements . | Mobile phone applications to prevent distraction reduce phone use. Drivers completed diaries and a questionnaire. Diaries show reliability issues with the applications. Management of involuntary distraction needs to be improved. |
S0001457519316537 | This study investigates the traffic conflict risks at the upstream approach of toll plaza during the vehicles diverging period from the time of arrival at the diverging area to that of entering the tollbooths . Based on the vehicles trajectory data extracted from unmanned aerial vehicle videos using an automated video analysis system vehicles collision risk is computed by extended time to collision . Then two time varying mixed logit models including time varying random effects logistic regression model and time varying random parameters logistic regression are developed to examine the time varying effects of influencing factors on vehicle collision risk and four models including the standard random effects logistic regression model standard random parameters logistic regression model distance varying random effects logistic regression model and distance varying random parameters logistic regression are developed for model performance comparison . The results indicate that the T RPLR model has the highest prediction accuracy . Eight influencing factors including following vehicles travel distance following vehicles initial lane following vehicles toll collection type leading vehicles toll collection type distance between two vehicles centroids and following vehicles speed are found to have time varying effects on collision risk . Meanwhile the first six factors are found to exhibit heterogeneous effects over the travel time . Another important finding is that the vehicle that comes from the innermost lane has an increasing trend to be involved in traffic conflicts whereas the collision risks of other vehicles decrease as the travel time increases . Moreover vehicles with higher speed have a decreasing probability to be involved in crashes over the travel time . Interestingly the results of D RPLR model are similar with that of T RPLR model . These findings provide helpful information for accurate assessment of collision risk which is a key step toward improving safety performance of the toll plazas diverging areas . | Developed time varying mixed logit models and distance varying mixed logit models for safety evaluation. Evaluated the collision risk of unconstrained vehicle motions at the upstream approach of toll plaza. Investigate the time varying and distance varying effects of influencing factors on vehicle collision risk at toll plaza diverging area. Investigated the heterogeneous effects of the same influencing factor on vehicle collision risk over the travel time. |
S0001457519316562 | The distance at which drivers follow other vehicles has been found to be linked to crash risk . Tailgating is both endemic and a leading cause of rear end crashes . Similarly drivers decisions about when to merge with a stream of traffic are likely to influence crash risk . Consistent with this it has been shown that crashes are more common at intersections where drivers more frequently have to slow for vehicles pulling out into insufficient gaps . Therefore the development of reliable and valid measures of both of these driving behaviours would facilitate further crash prevention research . Given the problems associated with assessing these behaviours during real driving we developed new video based measures . In our new following distance measure participants view videos shot from the perspective of a driver who is following another vehicle at a range of distances across a variety of traffic environments . On each trial participants report their own minimum comfortable following distance relative to the following distance depicted in the video . In our new test of gap acceptance behaviour participants view a series of video clips and indicate when they would pull out into the approaching stream of traffic shown in each clip . The two new measures each yielded reliable data and we found that young drivers made riskier choices than older drivers for both following distance and gap acceptance . These age related differences are consistent with those found in observational studies of real driving supporting the proposal that the new tests could potentially be used as proxies for these crash related driving behaviours in both lab based research and large scale online studies . | Drivers following distance and gap acceptance behaviours are related to crash risk. These behaviours are difficult to measure in real driving. Video based measures of following distance and gap acceptance were created. Results from evaluations supported the validity and reliability of the tests. These new measures are suitable and freely available for use in online research. |
S0001457519316574 | Bicyclists are vulnerable road users as they are not protected during a road collision . Although numerous studies have been conducted to understand the parameters contributing to bicyclists injury severity most of these studies have focused on the relationship between crash severity and road environmental vehicle and human demographic parameters . No study has been found that investigated the relationship of bicyclists injury severity with speed and mass of both vehicles as well as other crash dynamics aspects . This study developed a modelling framework to investigate the effect of variables such as speed mass and crash angle on bicyclists injury severity in bicycle car crashes at intersections . A combination of Newtonian Mechanics and statistical analysis was utilised to develop this theory . This modelling process followed a two step approach . In the first step Newtonian Mechanics was used to develop numerical models to estimate the impact force applied to the bicyclist . Variables affecting the associated impact forces were then identified . In the second step a mixed binary logistic regression model was developed to estimate injury severity of a bicycle vehicle crash as a function of mass of both vehicles speed of both vehicles before and after the crash restraint use and age of bicyclist . Transport Accident Commission validated crash data was used to develop the model . The results of the numerical models showed that kinetic energy of the car before crash and kinetic energy of the bicycle after crash are important parameters affecting the injury severity of the cyclist in bicycle vehicle crashes . The results of the mixed binary logistic regression model confirmed that the addition of kinetic energy of the car before crash and the kinetic energy of the bicycle post crash had a statistically significant effect on injury severity of bicyclist . The results further showed that older bicyclists were involved in higher severity crashes and helmet wearing reduced the injury severity of the bicyclist . | This study developed a modelling framework to investigate the effect of variables such as speed mass and crash angle on bicyclists injury severity in bicycle car crashes at intersections. A combination of Newtonian Mechanics and statistical analysis was utilised to develop this theory. The results showed that kinetic energy of the car before crash and kinetic energy of the bicycle after crash are important parameters affecting the injury severity of the cyclist in bicycle vehicle crashes. The results further showed that older bicyclists were involved in higher severity crashes and helmet wearing reduced the injury severity of the bicyclist. |
S0001457519316811 | Cycling is increasingly promoted as a sustainable transport mode . However bicyclists are more vulnerable to fatality and severe injury in road crashes compared to vehicle occupants . It is necessary to identify the contributory factors to crashes and injuries involving bicyclists . For the prediction of motor vehicle crashes comprehensive traffic count data i.e . AADT and vehicle kilometer traveled are commonly available to proxy the exposure . However extensive bicycle count data are usually not available . In this study revealed bicycle trip data of a public bicycle rental system in the Greater London is used to proxy the bicycle crash exposure . Random parameter negative binomial models are developed to measure the relationship between possible risk factors and bicycle crash frequency at the zonal level based on the crash data in the Greater London in 20122013 . Results indicate that model taking the bicycle use time as the exposure measure is superior to the other counterparts with the lowest AIC and BIC . Bicycle crash frequency is positively correlated to road density commercial area proportion of elderly male and white race and median household income . Additionally separate bicycle crash prediction models are developed for different seasons . Effects of the presence of Cycle Superhighway and proportion of green area on bicycle crash frequency can vary across seasons . Findings of this study are indicative to the development of bicycle infrastructures traffic management and control and education and enforcement strategies that can enhance the safety awareness of bicyclists and reduce their crash risk in the long run . | This study investigates the factors contributing to bicycle crash frequency at zonal level. Usage data of a public bicycle rental system is used to estimate the bicycle crash exposure. Road density land use bicycle infrastructure demographic and socioeconomics affect the bicycle crash frequency. Effects of bicycle infrastructure and land use on bicycle crash frequency vary across seasons. |
S0001457519316859 | We have investigated the accidents statistics of Europe and North America that are provided by the UN . This investigation has shown that accidents due to the traffic represent around 50 of the total number of accidents every year . Among them rear end collisions hold a 20 share . These numbers display the fact that the interaction between drivers can be held responsible of those incidents . In this respect we have explored the reasons behind the conflict situations that may be responsible of the occurrence of rear end collisions by the mean of a cognitive psychology based cellular automata model . Indeed through field experiments performed by an embedded camera we have extricated a psychological cognitive process of anticipation . We have defined the latter as the tendency of drivers to accelerate based on the history of their predecessor . Then we have exploited the tools of the physics of traffic by which we have developed a CA model that take into consideration this process . As a result we were able to generate those incidents situations . By considering two types of drivers conservative who respect the learned information about the safe manoeuvres but make mistakes or aggressive who violate those secure processes we have proved the complexity of the relationship between the states of the traffic flow and the drivers behaviours . In fact we have shown that rear end collisions are a result of the anticipation as a response of the drivers to the traffic conditions the congestion . Moreover we have also highlighted an improvement of the flow in the congested state up to 11 due to the anticipation but that can only be achieved through vehicle to vehicle communication . Finally we have investigated the hot spots . We have found that the traffic perturbations that generate those hot spots and can be responsible of collisions are more likely to be located away in the downstream direction . The distance between the two locations depends on the traffic density . This difference between the positions of the traffic perturbation and the hot spot has showcased the complexity in time and space of the transmission and the reception of deceleration information by the drivers . | A cognitive anticipation model based on cellular automata is developed to investigate rear end collisions. Drivers are sorted into two types according to the differences in their psychology. A complex relationship between traffic flow state and rear end collisions is shown. Anticipation is found to ameliorate the flow to the detriment of the safety. Hot spots are investigated. |
S0001457519316884 | The purpose of this study is to summarize the evidence for the association between exposure to a motor vehicle collision and future low back pain . Persistent low back pain is a relatively common complaint after acute injury in a MVC with a reported 1year post crash prevalence of at least 31 of exposed individuals . Interpretation of this finding is challenging given the high incidence of LBP in the general population that is not exposed to a MVC . Risk studies with comparison control groups need to be examined in a systematic review . A systematic search of five electronic databases from 1998 to 2019 was performed . Eligible studies describing exposure to a MVC and risk of future non specific LBP were critically appraised using the Quality in Prognosis Studies instrument . The results were summarized using best evidence synthesis principles a random effects meta analysis and testing for publication bias . The search strategy yielded 1136 articles three of which were found to be at low to medium risk of bias after critical appraisal . All three studies reported a positive association between an acute injury in a MVC and future LBP . Pooled analysis of the results resulted in an unadjusted relative risk of future LBP in the MVC exposed and injured population versus the non exposed population of 2.7 which equates to a 63 attributable risk under the exposed . There was a consistent positive association in the critically reviewed literature that investigated the risk of future LBP following an acute MVC related injury . For the patient with chronic low back pain who was initially injured in a MVC more often than not the condition was caused by the MVC . These findings are likely to be of interest to clinicians insurers patients governments and the courts . Future studies from both general and clinical populations would help strengthen these results . | The relative risk of future low back pain is 2.7 after injury in a car crash. 63 of ongoing low back pain can be attributed to the prior injury in a car crash. Rear end crashes without injury do not increase the risk of future low back pain. Further cohort studies are needed that control for pre injury confounding. |
S0001457519316896 | It has been suggested that Variable Message Signs become less effective at communicating important traffic information when irrelevant information is also displayed on them . The purpose of this study was to examine if practice reading irrelevant information on a VMS influenced compliance with and memory for a detour message . Thirty nine participants were randomly assigned to one of three groups who drove a simulated road one receiving only a detour message on the VMS one group received irrelevant VMS messages before the detour message and a third group received the same messages but the detour message was inconsistent with their destination . Of interest were both the participants compliance with the target detour message as well as their later recall and recognition of the message . The results suggested that first and foremost there was significantly lower compliance with the detour message when it had been preceded by irrelevant messages on the VMS . All of the groups showed reasonably good memory for the detour message . The implications of the present study are that presentation of irrelevant messages including advertisements and safety slogans may result in reduced compliance to traffic relevant messages on VMSs . | We asked if irrelevant VMS messages diminish the effectiveness of relevant ones. Previous research suggested that irrelevant messages do not. Our findings indicated that they result in lower compliance with relevant messages. |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.