To meet the requirements for high-risk testing scenarios in the safety assessment of advanced driver assistance systems(ADASs),this study selected 239 vehicle-to-powered two-wheeler accidents occurring in Xiangtan Cou...To meet the requirements for high-risk testing scenarios in the safety assessment of advanced driver assistance systems(ADASs),this study selected 239 vehicle-to-powered two-wheeler accidents occurring in Xiangtan County from the China In-depth Mobility Safety Study—Traffic Accident(CIMSS-TA)database.Seven scenario elements were selected from the levels of static road elements,dynamic traffic participants and environment elements.The accident characteristics were obtained through statistical analysis.The results showed that 75.73%of accidents occurred at T-junctions/intersections,and 34.73%were caused by visual obstructions.Six typical vehicle-to-powered two-wheeler crash scenarios were established by cluster analysis,including two straight road scenarios(scenarios 3 and 6),two T-junction scenarios(scenarios 1 and 5)and two intersection scenarios(scenarios 2 and 4).Furthermore,six vehicle-to-powered two-wheeler testing scenarios,which represent the traffic environment characteristics of Chinese county-level districts,were constructed by analysing the vehicle/powered two-wheeler speed,the first collision point of the vehicle,the obstacle type and location,etc.The results showed that the vehicle speed in scenario 4 was higher than that in scenario 2,with average values of 34.32 km/h and 21.99 km/h,respectively.The results of this study provide testing scenarios for the safety assessment of ADASs,and contribute to improving vehicle active safety technology.展开更多
To realize the widespread application and continuous functional development of intelligent vehicles,test and evaluation of vehicle's functionality and Safety Performance in complex off-road scenarios are fundament...To realize the widespread application and continuous functional development of intelligent vehicles,test and evaluation of vehicle's functionality and Safety Performance in complex off-road scenarios are fundamental.Since traditional distance-based road tests cannot meet the evolving test requirements,a method to design the function-based off-road testing scenario library for intelligent vehicles(IV)is proposed in this paper.The testing scenario library is defined as a critical set of scenarios that can be used for IV tests.First,for the complex and diverse off-road scenarios,a hierarchical,structural model of the test scenario is built.Then,the critical test scenarios are selected adaptively according to the vehicle model to be tested.Next,those parameters representing the challenging test scenarios are selected.The selected parameters need to fit the natural distribution probability of scenarios.The critical test-scenario library is built combing these parameters with the structural model.Finally,the test scenarios that are most approximate to the natural driving scenario are determined with importance sampling theory.The test-scenario library built with this method can provide more critical test scenarios,and is widely applicable despite different vehicle models.Verified by simulation in the off-road interaction scenarios,test would be accelerated significantly with this method,about 800 times faster than testing in the natural road environment.展开更多
To get a better understanding of the spatial impact of organic discharges on stream water quality,a "scenario-testing" approach was proposed to examine how a change in plant treatment efficiency would affect...To get a better understanding of the spatial impact of organic discharges on stream water quality,a "scenario-testing" approach was proposed to examine how a change in plant treatment efficiency would affect dissolved oxygen(DO) concentration along a stream.An "upper-lower" boundary technique was applied to conduct sensitivity analysis to observe the responses of DO concentration to different DO-related parameters.The results show a non-linear discrepancy of biochemical oxygen demand(BOD) and DO concentration among different treatment scenarios,which indicates the higher the efficiency of the plant treatment,the shorter the time the stream needs to recover.The sensitivity analysis reveals that the larger the amount of the waste discharge,the more sensitive the BOD to the biological removal parameter.In addition,the DO is more sensitive to the biological removal parameter than to the reaeration parameter.展开更多
基金funded by the National Key R&D Program of China(Grant No.2022YFB4300300)the Hunan Science Foundation for Distinguished Young Scholars of China(Grant No.2021JJ110059)+2 种基金the National Natural Science Foundation of China(Grants No.52105523 and 52075553)the Natural Science Foundation of Shandong(Grant No.ZR2021QE249)the China Postdoctoral Science Foundation Funded Project(Grant No.2021M703559).
文摘To meet the requirements for high-risk testing scenarios in the safety assessment of advanced driver assistance systems(ADASs),this study selected 239 vehicle-to-powered two-wheeler accidents occurring in Xiangtan County from the China In-depth Mobility Safety Study—Traffic Accident(CIMSS-TA)database.Seven scenario elements were selected from the levels of static road elements,dynamic traffic participants and environment elements.The accident characteristics were obtained through statistical analysis.The results showed that 75.73%of accidents occurred at T-junctions/intersections,and 34.73%were caused by visual obstructions.Six typical vehicle-to-powered two-wheeler crash scenarios were established by cluster analysis,including two straight road scenarios(scenarios 3 and 6),two T-junction scenarios(scenarios 1 and 5)and two intersection scenarios(scenarios 2 and 4).Furthermore,six vehicle-to-powered two-wheeler testing scenarios,which represent the traffic environment characteristics of Chinese county-level districts,were constructed by analysing the vehicle/powered two-wheeler speed,the first collision point of the vehicle,the obstacle type and location,etc.The results showed that the vehicle speed in scenario 4 was higher than that in scenario 2,with average values of 34.32 km/h and 21.99 km/h,respectively.The results of this study provide testing scenarios for the safety assessment of ADASs,and contribute to improving vehicle active safety technology.
基金National Natural Science Foundation of China No.U19A2083.
文摘To realize the widespread application and continuous functional development of intelligent vehicles,test and evaluation of vehicle's functionality and Safety Performance in complex off-road scenarios are fundamental.Since traditional distance-based road tests cannot meet the evolving test requirements,a method to design the function-based off-road testing scenario library for intelligent vehicles(IV)is proposed in this paper.The testing scenario library is defined as a critical set of scenarios that can be used for IV tests.First,for the complex and diverse off-road scenarios,a hierarchical,structural model of the test scenario is built.Then,the critical test scenarios are selected adaptively according to the vehicle model to be tested.Next,those parameters representing the challenging test scenarios are selected.The selected parameters need to fit the natural distribution probability of scenarios.The critical test-scenario library is built combing these parameters with the structural model.Finally,the test scenarios that are most approximate to the natural driving scenario are determined with importance sampling theory.The test-scenario library built with this method can provide more critical test scenarios,and is widely applicable despite different vehicle models.Verified by simulation in the off-road interaction scenarios,test would be accelerated significantly with this method,about 800 times faster than testing in the natural road environment.
基金Projects PGSD3-334033-2006 supported by the Natural Sciences and Engineering Research Council of Canada2007-2008 by the Canadian Forest Service of Natural Resources
文摘To get a better understanding of the spatial impact of organic discharges on stream water quality,a "scenario-testing" approach was proposed to examine how a change in plant treatment efficiency would affect dissolved oxygen(DO) concentration along a stream.An "upper-lower" boundary technique was applied to conduct sensitivity analysis to observe the responses of DO concentration to different DO-related parameters.The results show a non-linear discrepancy of biochemical oxygen demand(BOD) and DO concentration among different treatment scenarios,which indicates the higher the efficiency of the plant treatment,the shorter the time the stream needs to recover.The sensitivity analysis reveals that the larger the amount of the waste discharge,the more sensitive the BOD to the biological removal parameter.In addition,the DO is more sensitive to the biological removal parameter than to the reaeration parameter.
