Highway work zones are locations where severe traffic crashes tend to occur.Most of the extant research on work zone crash severity neglects the discrepancy in the injuries sustained by different drivers involved in t...Highway work zones are locations where severe traffic crashes tend to occur.Most of the extant research on work zone crash severity neglects the discrepancy in the injuries sustained by different drivers involved in the same crash.Admittedly,it is essential to analyse crash-level factors to their highest injury severity;but it is equally important to understand driver-level contributing factors to their injury severity to establish effective safety countermeasures to minimize drivers’injury severity.Thus,this research aims to identify the factors with significant impacts on the driver injury severity of work zone crashes and estimate their effects on each severity level.Data on 3880 drivers involved in 2134 work zone crashes are obtained from the Crash Report Sampling System(CRSS)database of the United States and employed for the empirical investigation.A Bayesian hierarchical generalized ordered probit model is advocated for analysing the driver injury severity.Model performance indices suggest that the advocated hierarchical model is superior to the generalized ordered probit model,and considerable within-crash correlation is found across the observed driver injury severity.The estimated parameters show that driver age and sex,alcohol use,vehicle age and type,speeding and speed limit,weather conditions,lighting conditions and crash type have significant effects on the driver injury severity in work zone crashes.Marginal effects of the significant factors on each divided injury severity level are also estimated.Countermeasures are proposed from the results to reduce severe injuries sustained by drivers involved in work zone crashes.展开更多
Purpose–This study aims to investigate the safety and liability of autonomous vehicles(AVs),and identify the contributing factors quantitatively so as to provide potential insights on safety and liability of AVs.Desi...Purpose–This study aims to investigate the safety and liability of autonomous vehicles(AVs),and identify the contributing factors quantitatively so as to provide potential insights on safety and liability of AVs.Design/methodology/approach–The actual crash data were obtained from California DMV and Sohu websites involved in collisions of AVs from 2015 to 2021 with 210 observations.The Bayesian random parameter ordered probit model was proposed to reflect the safety and liability of AVs,respectively,as well as accommodating the heterogeneity issue simultaneously.Findings–The findings show that day,location and crash type were significant factors of injury severity while location and crash reason were significant influencing the liability.Originality/value–The results provide meaningful countermeasures to support the policymakers or practitioners making strategies or regulations about AV safety and liability.展开更多
The COVID-19 pandemic had an enormous impact on the vegetable supply chain in China.Effective evaluation of the pandemic’s influences on vegetable production is vital for policy settings to enhance the security of ve...The COVID-19 pandemic had an enormous impact on the vegetable supply chain in China.Effective evaluation of the pandemic’s influences on vegetable production is vital for policy settings to enhance the security of vegetable supply.Based on first-hand data from 526 households,we explored regional differences in different types of loss and potential factors affecting the severity farmer households suffered during the pandemic.The results underline that sales contraction and price volatility in the context of interruption of supply chain dominate the total losses during the pandemic.Such losses differ across provinces and are more substantial in provinces with stricter confinement measures.Farmer households’participation in local market and modern marketing methods helps mitigate the negative effects of the COVID-19 shock,while labor hiring and facilities adoption in production widen the losses due to the shortage in the workforce.In the future,the vegetable industry practitioners and relevant government departments should work together to coordinate the development of short and long supply chains and strengthen the stability and security of the vegetable supply chain.展开更多
基金supported by the Open Fund of the Key Laboratory of Highway Engineering of Ministry of Education(Changsha University of Science&Technology)(Grant No.kfj230301).
文摘Highway work zones are locations where severe traffic crashes tend to occur.Most of the extant research on work zone crash severity neglects the discrepancy in the injuries sustained by different drivers involved in the same crash.Admittedly,it is essential to analyse crash-level factors to their highest injury severity;but it is equally important to understand driver-level contributing factors to their injury severity to establish effective safety countermeasures to minimize drivers’injury severity.Thus,this research aims to identify the factors with significant impacts on the driver injury severity of work zone crashes and estimate their effects on each severity level.Data on 3880 drivers involved in 2134 work zone crashes are obtained from the Crash Report Sampling System(CRSS)database of the United States and employed for the empirical investigation.A Bayesian hierarchical generalized ordered probit model is advocated for analysing the driver injury severity.Model performance indices suggest that the advocated hierarchical model is superior to the generalized ordered probit model,and considerable within-crash correlation is found across the observed driver injury severity.The estimated parameters show that driver age and sex,alcohol use,vehicle age and type,speeding and speed limit,weather conditions,lighting conditions and crash type have significant effects on the driver injury severity in work zone crashes.Marginal effects of the significant factors on each divided injury severity level are also estimated.Countermeasures are proposed from the results to reduce severe injuries sustained by drivers involved in work zone crashes.
基金National Natural Science Foundation of China(No.52072214)the project of Tsinghua University-Toyota Joint Research Center for AI technology of Automated Vehicle(No.TTAD2021-10).
文摘Purpose–This study aims to investigate the safety and liability of autonomous vehicles(AVs),and identify the contributing factors quantitatively so as to provide potential insights on safety and liability of AVs.Design/methodology/approach–The actual crash data were obtained from California DMV and Sohu websites involved in collisions of AVs from 2015 to 2021 with 210 observations.The Bayesian random parameter ordered probit model was proposed to reflect the safety and liability of AVs,respectively,as well as accommodating the heterogeneity issue simultaneously.Findings–The findings show that day,location and crash type were significant factors of injury severity while location and crash reason were significant influencing the liability.Originality/value–The results provide meaningful countermeasures to support the policymakers or practitioners making strategies or regulations about AV safety and liability.
基金This paper was supported by the National Social Science Foundation of China(19ZDA106)the National Science Foundation of China(71773109)the European Commission Project 777742(EC H2020-MSCA-RISE-2017).
文摘The COVID-19 pandemic had an enormous impact on the vegetable supply chain in China.Effective evaluation of the pandemic’s influences on vegetable production is vital for policy settings to enhance the security of vegetable supply.Based on first-hand data from 526 households,we explored regional differences in different types of loss and potential factors affecting the severity farmer households suffered during the pandemic.The results underline that sales contraction and price volatility in the context of interruption of supply chain dominate the total losses during the pandemic.Such losses differ across provinces and are more substantial in provinces with stricter confinement measures.Farmer households’participation in local market and modern marketing methods helps mitigate the negative effects of the COVID-19 shock,while labor hiring and facilities adoption in production widen the losses due to the shortage in the workforce.In the future,the vegetable industry practitioners and relevant government departments should work together to coordinate the development of short and long supply chains and strengthen the stability and security of the vegetable supply chain.
