The heavy-duty vehicle fleet involved in delivering water and sand makes noticeable issues of exhaust emissions and fuel consumption in the process of shale gas development. To examine the possibility of converting th...The heavy-duty vehicle fleet involved in delivering water and sand makes noticeable issues of exhaust emissions and fuel consumption in the process of shale gas development. To examine the possibility of converting these heavy-duty diesel engines to run on natural gas-diesel dual-fuel, a transient engine duty cycle representing the real-world engine working conditions is necessary. In this paper, a methodology is proposed, and a target engine duty cycle comprising of 2231 seconds is developed from on-road data collected from 11 on-road sand and water hauling trucks. The similarity of inherent characteristics of the developed cycle and the base trip observed is evidenced by the 2.05% error of standard deviation and average values for normalized engine speed and engine torque. Our results show that the proposed approach is expected to produce a representative cycle of in-use heavy-duty engine behavior.展开更多
In recent years,with rapid increases in the number of vehicles in China,the contribution of vehicle exhaust emissions to air pollution has become increasingly prominent.To achieve the precise control of emissions,on-r...In recent years,with rapid increases in the number of vehicles in China,the contribution of vehicle exhaust emissions to air pollution has become increasingly prominent.To achieve the precise control of emissions,on-road remote sensing(RS)technology has been developed and applied for law enforcement and supervision.However,data quality is still an existing issue affecting the development and application of RS.In this study,the RS data from a cross-road RS system used at a single site(from 2012 to 2015)were collected,the data screening process was reviewed,the issues with data quality were summarized,a new method of data screening and calibration was proposed,and the effectiveness of the improved data quality control methods was finally evaluated.The results showed that this method reduces the skewness and kurtosis of the data distribution by up to nearly 67%,which restores the actual characteristics of exhaust diffusion and is conducive to the identification of actual clean and high-emission vehicles.The annual variability of emission factors of nitric oxide decreases by 60%-on average-eliminating the annual drift of fleet emissions and improving data reliability.展开更多
Recent fossil fuel shortages and global warming related problems have caused a substantial shift from internal combustion engine vehicles towards EVs.This paper explores the thorough review of battery charging infrast...Recent fossil fuel shortages and global warming related problems have caused a substantial shift from internal combustion engine vehicles towards EVs.This paper explores the thorough review of battery charging infrastructure from wired connection to on-road wireless charging for an EV.The initial part of the paper deals with the wired charging and its power electronics infrastructure.The later portion deals with the wireless charging where both static and On-Road types are discussed.Furthermore,various aspects of wireless power transfer are also discussed.The Market scenario and future growth prospects are reviewed and presented in last section of the paper.展开更多
The objective of this study is to estimate the vehicle kilometer traveled（VKT） and on-road emissions using the traffic volume in urban. We estimated two VKT; one is based on registered vehicles and the other is base...The objective of this study is to estimate the vehicle kilometer traveled（VKT） and on-road emissions using the traffic volume in urban. We estimated two VKT; one is based on registered vehicles and the other is based on traffic volumes. VKT for registered vehicles was 2.11 times greater than that of the applied traffic volumes because each VKT estimation method is different. Therefore, we had to define the inner VKT is moved VKT inner in urban to compare two values. Also, we focused on freight modes because these are discharged much air pollutant emissions. From analysis results, we found middle and large trucks registered in other regions traveled to target city in order to carry freight, target city has included many industrial and logistics areas. Freight is transferred through the harbors,large logistics centers, or via locations before being moved to the final destination. During this process, most freight is moved by middle and large trucks, and trailers rather than small trucks for freight import and export. Therefore, these trucks from other areas are inflow more than registered vehicles. Most emissions from diesel trucks had been overestimated in comparison to VKT from applied traffic volumes in target city. From these findings, VKT is essential based on traffic volume and travel speed on road links in order to estimate accurately the emissions of diesel trucks in target city. Our findings support the estimation of the effect of on-road emissions on urban air quality in Korea.展开更多
Tractor-trailer vehicles,which are composed of a car-like tractor towing a passive trailer,have been widely deployed in the transportation industry,and trajectory planning is a critical step in enabling such a system ...Tractor-trailer vehicles,which are composed of a car-like tractor towing a passive trailer,have been widely deployed in the transportation industry,and trajectory planning is a critical step in enabling such a system to drive autonomously.Owing to the properties of being highly nonlinear and nonholonomic with complex dynamics,the tractor-trailer system poses great challenges to the development of motion-planning algorithms.In this study,an indirect trajectory planning framework for a tractor-trailer vehicle under on-road driving is presented to deal with the problem that the traditional planning framework cannot consider the feasibility and quality simultaneously in real-time trajectory generation of the tractor-trailer vehicle.The indirect planning framework can easily handle complicated tractor-trailer dynamics and generate high-quality,obstacle-free trajectory using quintic polynomial spline,speed profile optimization,forward simulation,and properly designed cost functions.Simulations under different driving scenarios and trajectories with different driving requirements are conducted to validate the performance of the proposed framework.展开更多
文摘The heavy-duty vehicle fleet involved in delivering water and sand makes noticeable issues of exhaust emissions and fuel consumption in the process of shale gas development. To examine the possibility of converting these heavy-duty diesel engines to run on natural gas-diesel dual-fuel, a transient engine duty cycle representing the real-world engine working conditions is necessary. In this paper, a methodology is proposed, and a target engine duty cycle comprising of 2231 seconds is developed from on-road data collected from 11 on-road sand and water hauling trucks. The similarity of inherent characteristics of the developed cycle and the base trip observed is evidenced by the 2.05% error of standard deviation and average values for normalized engine speed and engine torque. Our results show that the proposed approach is expected to produce a representative cycle of in-use heavy-duty engine behavior.
基金supported by National Key R&D Program of China(Nos.2019YFC0214800 and 2017YFC0212100)Beijing Municipal Science&Technology Commission(No.Z181100005418015)。
文摘In recent years,with rapid increases in the number of vehicles in China,the contribution of vehicle exhaust emissions to air pollution has become increasingly prominent.To achieve the precise control of emissions,on-road remote sensing(RS)technology has been developed and applied for law enforcement and supervision.However,data quality is still an existing issue affecting the development and application of RS.In this study,the RS data from a cross-road RS system used at a single site(from 2012 to 2015)were collected,the data screening process was reviewed,the issues with data quality were summarized,a new method of data screening and calibration was proposed,and the effectiveness of the improved data quality control methods was finally evaluated.The results showed that this method reduces the skewness and kurtosis of the data distribution by up to nearly 67%,which restores the actual characteristics of exhaust diffusion and is conducive to the identification of actual clean and high-emission vehicles.The annual variability of emission factors of nitric oxide decreases by 60%-on average-eliminating the annual drift of fleet emissions and improving data reliability.
文摘Recent fossil fuel shortages and global warming related problems have caused a substantial shift from internal combustion engine vehicles towards EVs.This paper explores the thorough review of battery charging infrastructure from wired connection to on-road wireless charging for an EV.The initial part of the paper deals with the wired charging and its power electronics infrastructure.The later portion deals with the wireless charging where both static and On-Road types are discussed.Furthermore,various aspects of wireless power transfer are also discussed.The Market scenario and future growth prospects are reviewed and presented in last section of the paper.
基金supported by the Korea Transport Institute,Republic of Koreasupported by Technology Development to evaluate GHG Emissions Indices of Mobiles and Municipal Sustainability(Transport logistics project 14TLRP-CO84940-01) commissioned from KAIA
文摘The objective of this study is to estimate the vehicle kilometer traveled（VKT） and on-road emissions using the traffic volume in urban. We estimated two VKT; one is based on registered vehicles and the other is based on traffic volumes. VKT for registered vehicles was 2.11 times greater than that of the applied traffic volumes because each VKT estimation method is different. Therefore, we had to define the inner VKT is moved VKT inner in urban to compare two values. Also, we focused on freight modes because these are discharged much air pollutant emissions. From analysis results, we found middle and large trucks registered in other regions traveled to target city in order to carry freight, target city has included many industrial and logistics areas. Freight is transferred through the harbors,large logistics centers, or via locations before being moved to the final destination. During this process, most freight is moved by middle and large trucks, and trailers rather than small trucks for freight import and export. Therefore, these trucks from other areas are inflow more than registered vehicles. Most emissions from diesel trucks had been overestimated in comparison to VKT from applied traffic volumes in target city. From these findings, VKT is essential based on traffic volume and travel speed on road links in order to estimate accurately the emissions of diesel trucks in target city. Our findings support the estimation of the effect of on-road emissions on urban air quality in Korea.
基金the National Natural Science Foun-dation of China(No.61873165/U1764264)the Shanghai Automotive Industry Science and Technology Development Foundation(No.1807)。
文摘Tractor-trailer vehicles,which are composed of a car-like tractor towing a passive trailer,have been widely deployed in the transportation industry,and trajectory planning is a critical step in enabling such a system to drive autonomously.Owing to the properties of being highly nonlinear and nonholonomic with complex dynamics,the tractor-trailer system poses great challenges to the development of motion-planning algorithms.In this study,an indirect trajectory planning framework for a tractor-trailer vehicle under on-road driving is presented to deal with the problem that the traditional planning framework cannot consider the feasibility and quality simultaneously in real-time trajectory generation of the tractor-trailer vehicle.The indirect planning framework can easily handle complicated tractor-trailer dynamics and generate high-quality,obstacle-free trajectory using quintic polynomial spline,speed profile optimization,forward simulation,and properly designed cost functions.Simulations under different driving scenarios and trajectories with different driving requirements are conducted to validate the performance of the proposed framework.
