Road user charging (RUC) has a long history as a mechanism to recover<span style="font-family:""><span style="font-family:Verdana;"> infrastructure maintenance and capital costs. T...Road user charging (RUC) has a long history as a mechanism to recover<span style="font-family:""><span style="font-family:Verdana;"> infrastructure maintenance and capital costs. The present RUC systems are facing issues such as transparency, cross-subsidization, environmental concerns and </span><span style="font-family:Verdana;">reducing revenue due to the likes of lessening fuel tax as vehicles become more </span><span style="font-family:Verdana;">efficient. Therefore, this paper reviews the strengths and weaknesses of </span><span style="font-family:Verdana;">the present RUC mechanisms implemented in the world with respect to stakeholder problems and demands of the freight industry and to describe the need</span><span style="font-family:Verdana;"> for a more appropriate, practical and sustainable approach that can be used in the future. Finally, a model is proposed that is transparent and considers us</span><span style="font-family:Verdana;">age-based charging addressing most of the weaknesses highlighted in the models reviewed. Further, it considers externalities produced by heavy vehicles into a</span><span style="font-family:Verdana;">ccount. The model has the potential to provide answers to key stakeholder </span><span style="font-family:Verdana;">issues and will lead to a sustainable freight transport system in the future. Encourag</span><span style="font-family:Verdana;">ing fuel-efficient modes, optimization of loading, routing and logistics systems, and long term land use planning are a few of them.</span></span>展开更多
With the development of intelligent vehicles and autonomous driving technology,the safety of vulnerable road user(VRU)in traffic has been more guaranteed,and many research achievements have been made in the key area o...With the development of intelligent vehicles and autonomous driving technology,the safety of vulnerable road user(VRU)in traffic has been more guaranteed,and many research achievements have been made in the key area of collision avoidance decision-making methods.In this paper,the knowledge mapping method is used to mine the available literature in depth,and it is found that the research focus has shifted from the traditional accident cause analysis to emerging deep learning and virtual reality technology.This paper summarizes research on the three core dimensions of environmental perception,behavior cognition and collision avoidance decision-making in intelligent vehicle systems.In terms of perception,accurate identification of pedestrians and cyclists in complex environments is a major demand for VRU perception;in terms of behavior cognition,the coupling of VRU intention identification and motion trajectory prediction and other multiple factors needs further research;in terms of decision-making,the intention identification and trajectory prediction of collision objects are not included in the risk assessment model,and there is a lack of exploration specifically for cyclists'collision risk.On this basis,this paper provides guidance for the improvement of traffic safety of contemporary VRU under the conditions of intelligent and connected transportation.展开更多
Continuous changes in vehicle technology,road condition,traffic compositions initiate the change or updating of road users’cost models.So that it needs to practice a continuous revision or update periodically f...Continuous changes in vehicle technology,road condition,traffic compositions initiate the change or updating of road users’cost models.So that it needs to practice a continuous revision or update periodically for realistic estimation of costs and benefits.This paper presented the relationship and comparison between road users’cost along Addis Ababa-Adama newly constructed expressway using the Highway Development and Management(HDM-4)Software and manually using formulations developed in the Portuguese model.The method started with data collection.All input data were collected from primary and secondary sources.The primary data utilized an interview,and secondary data were sourced out from pertinent documents,both published and unpublished.More data were gathered that related to vehicles.The vehicles using the road are classified based on the manual from the Ethiopian Road Authority as cars,utilities,small bus,large bus,small truck,medium truck,heavy truck,and truck trailer.The collected data have been input into the HDM-4 interface;the output of the analysis was vehicle operating costs,travel time,and road users’cost as a summation.Using manual technique and HDM-4 Software,Birr 128.62/km/vehicle and Birr 139.23/km/vehicle,respectively,were found from road users’costs analysis.The result shows the difference of Birr 10.61.Also,the correlation coefficient of 0.75 is determined,which shows that the two results of road users’costs are highly related.As a result,the study reveals that the application of HDM-4 Software and the manual technique formulations from the Portuguese model can be adopted interchangeably to calculate Road Users’Cost of road sections in Ethiopia.Hence,the study results are expected to be an eye-opener for a future similar project by the concerned agencies.展开更多
Purpose–Time headway(THW)is an essential parameter in traffic safety and is used as a typical control variable by many vehicle control algorithms,especially in safety-critical ADAS and automated driving systems.Howev...Purpose–Time headway(THW)is an essential parameter in traffic safety and is used as a typical control variable by many vehicle control algorithms,especially in safety-critical ADAS and automated driving systems.However,due to the randomness of human drivers,THW cannot be accurately represented,affecting scholars’more profound research.Design/methodology/approach–In this work,two data sets are used as the experimental data to calculate the goodness-of-fit of 18 commonly used distribution models of THW to select the best distribution model.Subsequently,the characteristic parameters of traffic flow are extracted from the data set,and three variables with higher importance are extracted using the random forest model.Combining the best distribution model parameters of the data set,this study obtained a distribution model with adaptive parameters,and its performance and applicability are verified.Findings–In this work,two data sets are used as the experimental data to calculate the goodness-of-fit of 18 commonly used distribution models of THW to select the best distribution model.Subsequently,the characteristic parameters of traffic flow are extracted from the data set,and three variables with higher importance are extracted using the random forest model.Combining the best distribution model parameters of the data set,this study obtained a distribution model with adaptive parameters,and its performance and applicability are verified.Originality/value–The results show that the proposed model has a 62.7%performance improvement over the distribution model with fixed parameters.Moreover,the parameter function of the distribution model can be regarded as a quantitative analysis of the degree of influence of the traffic flow state on THW.展开更多
文摘Road user charging (RUC) has a long history as a mechanism to recover<span style="font-family:""><span style="font-family:Verdana;"> infrastructure maintenance and capital costs. The present RUC systems are facing issues such as transparency, cross-subsidization, environmental concerns and </span><span style="font-family:Verdana;">reducing revenue due to the likes of lessening fuel tax as vehicles become more </span><span style="font-family:Verdana;">efficient. Therefore, this paper reviews the strengths and weaknesses of </span><span style="font-family:Verdana;">the present RUC mechanisms implemented in the world with respect to stakeholder problems and demands of the freight industry and to describe the need</span><span style="font-family:Verdana;"> for a more appropriate, practical and sustainable approach that can be used in the future. Finally, a model is proposed that is transparent and considers us</span><span style="font-family:Verdana;">age-based charging addressing most of the weaknesses highlighted in the models reviewed. Further, it considers externalities produced by heavy vehicles into a</span><span style="font-family:Verdana;">ccount. The model has the potential to provide answers to key stakeholder </span><span style="font-family:Verdana;">issues and will lead to a sustainable freight transport system in the future. Encourag</span><span style="font-family:Verdana;">ing fuel-efficient modes, optimization of loading, routing and logistics systems, and long term land use planning are a few of them.</span></span>
基金funded by the National Natural Science Foundation of China,grant numbers 52072214 and 52242213.
文摘With the development of intelligent vehicles and autonomous driving technology,the safety of vulnerable road user(VRU)in traffic has been more guaranteed,and many research achievements have been made in the key area of collision avoidance decision-making methods.In this paper,the knowledge mapping method is used to mine the available literature in depth,and it is found that the research focus has shifted from the traditional accident cause analysis to emerging deep learning and virtual reality technology.This paper summarizes research on the three core dimensions of environmental perception,behavior cognition and collision avoidance decision-making in intelligent vehicle systems.In terms of perception,accurate identification of pedestrians and cyclists in complex environments is a major demand for VRU perception;in terms of behavior cognition,the coupling of VRU intention identification and motion trajectory prediction and other multiple factors needs further research;in terms of decision-making,the intention identification and trajectory prediction of collision objects are not included in the risk assessment model,and there is a lack of exploration specifically for cyclists'collision risk.On this basis,this paper provides guidance for the improvement of traffic safety of contemporary VRU under the conditions of intelligent and connected transportation.
文摘Continuous changes in vehicle technology,road condition,traffic compositions initiate the change or updating of road users’cost models.So that it needs to practice a continuous revision or update periodically for realistic estimation of costs and benefits.This paper presented the relationship and comparison between road users’cost along Addis Ababa-Adama newly constructed expressway using the Highway Development and Management(HDM-4)Software and manually using formulations developed in the Portuguese model.The method started with data collection.All input data were collected from primary and secondary sources.The primary data utilized an interview,and secondary data were sourced out from pertinent documents,both published and unpublished.More data were gathered that related to vehicles.The vehicles using the road are classified based on the manual from the Ethiopian Road Authority as cars,utilities,small bus,large bus,small truck,medium truck,heavy truck,and truck trailer.The collected data have been input into the HDM-4 interface;the output of the analysis was vehicle operating costs,travel time,and road users’cost as a summation.Using manual technique and HDM-4 Software,Birr 128.62/km/vehicle and Birr 139.23/km/vehicle,respectively,were found from road users’costs analysis.The result shows the difference of Birr 10.61.Also,the correlation coefficient of 0.75 is determined,which shows that the two results of road users’costs are highly related.As a result,the study reveals that the application of HDM-4 Software and the manual technique formulations from the Portuguese model can be adopted interchangeably to calculate Road Users’Cost of road sections in Ethiopia.Hence,the study results are expected to be an eye-opener for a future similar project by the concerned agencies.
文摘Purpose–Time headway(THW)is an essential parameter in traffic safety and is used as a typical control variable by many vehicle control algorithms,especially in safety-critical ADAS and automated driving systems.However,due to the randomness of human drivers,THW cannot be accurately represented,affecting scholars’more profound research.Design/methodology/approach–In this work,two data sets are used as the experimental data to calculate the goodness-of-fit of 18 commonly used distribution models of THW to select the best distribution model.Subsequently,the characteristic parameters of traffic flow are extracted from the data set,and three variables with higher importance are extracted using the random forest model.Combining the best distribution model parameters of the data set,this study obtained a distribution model with adaptive parameters,and its performance and applicability are verified.Findings–In this work,two data sets are used as the experimental data to calculate the goodness-of-fit of 18 commonly used distribution models of THW to select the best distribution model.Subsequently,the characteristic parameters of traffic flow are extracted from the data set,and three variables with higher importance are extracted using the random forest model.Combining the best distribution model parameters of the data set,this study obtained a distribution model with adaptive parameters,and its performance and applicability are verified.Originality/value–The results show that the proposed model has a 62.7%performance improvement over the distribution model with fixed parameters.Moreover,the parameter function of the distribution model can be regarded as a quantitative analysis of the degree of influence of the traffic flow state on THW.
