The relationship between the opposing left-turn conflict and the traffic participants was analyzed in this study. Based on the traffic conflict technology, the image data were collected in a real traffic situation. Th...The relationship between the opposing left-turn conflict and the traffic participants was analyzed in this study. Based on the traffic conflict technology, the image data were collected in a real traffic situation. The relationship was investigated under two different conditions. The number of opposing left-turn conflicts was positively correlated with the number of left-turn vehicles while the ratio of left-turn vehicles to opposing vehicles was less than 1, and showed a positive correlation with the number of opposing-through vehicles when the ratio of left-turn vehicles to opposing vehi- cles was more than 1. In other words, the opposing left-turn risk was positively correlated with the number of the minor traffic participants, which had a negative effect on the whole traffic system op- eration.展开更多
The flashing yellow arrow(FYA)signal display creates an opportunity to enhance the leftturn phase with a variable mode that can be changed on demand.This research develops an integrated general purpose data collection...The flashing yellow arrow(FYA)signal display creates an opportunity to enhance the leftturn phase with a variable mode that can be changed on demand.This research develops an integrated general purpose data collection module that time stamps detector and phase state changes within a National Electrical Manufacturers Association(NEMA)actuated traffic signal controller to provide recommendations for the flashing yellow arrow left-turn mode on a cycle-by-cycle basis.115 left-turn approaches at 38 intersections with locations across the State of Florida were analyzed totaling 1370 h of video data processed including off-peak and peak conditions.Video data extraction was an essential step in developing thegap thresholds for the permissive left-turn.Actual intersection field data were obtained through loop detector mapping to the controller in the lab in real-time mode using a peerto-peer logic environment.A custom communications software was developed to retrieve instantaneous channel input data,synchronize opposing through green phase,analyze traffic information,provide the algorithm decision,and generate a real-time log recording the events to determine whether it would be optimal to switch the red arrow to a flashing yellow arrow.The algorithm determines the time interval between the successive arrivals of vehicles and computes the corresponding headway for each lane by cycle on a secondby-second basis.Peer-to-peer logic is a necessary step to verify and validate new traffic concepts prior to field-testing and offers the advantage of acquiring and analyzing realtime traffic data coupled with video feed with the benefit of a safe environment.展开更多
基金Supported by the Programme of Introducing Talents of Discipline to Universities (B12022)
文摘The relationship between the opposing left-turn conflict and the traffic participants was analyzed in this study. Based on the traffic conflict technology, the image data were collected in a real traffic situation. The relationship was investigated under two different conditions. The number of opposing left-turn conflicts was positively correlated with the number of left-turn vehicles while the ratio of left-turn vehicles to opposing vehicles was less than 1, and showed a positive correlation with the number of opposing-through vehicles when the ratio of left-turn vehicles to opposing vehi- cles was more than 1. In other words, the opposing left-turn risk was positively correlated with the number of the minor traffic participants, which had a negative effect on the whole traffic system op- eration.
基金The work reported in this paper is part of a research project under contract number BDV 24-977-21,which is sponsored by the FDOT。
文摘The flashing yellow arrow(FYA)signal display creates an opportunity to enhance the leftturn phase with a variable mode that can be changed on demand.This research develops an integrated general purpose data collection module that time stamps detector and phase state changes within a National Electrical Manufacturers Association(NEMA)actuated traffic signal controller to provide recommendations for the flashing yellow arrow left-turn mode on a cycle-by-cycle basis.115 left-turn approaches at 38 intersections with locations across the State of Florida were analyzed totaling 1370 h of video data processed including off-peak and peak conditions.Video data extraction was an essential step in developing thegap thresholds for the permissive left-turn.Actual intersection field data were obtained through loop detector mapping to the controller in the lab in real-time mode using a peerto-peer logic environment.A custom communications software was developed to retrieve instantaneous channel input data,synchronize opposing through green phase,analyze traffic information,provide the algorithm decision,and generate a real-time log recording the events to determine whether it would be optimal to switch the red arrow to a flashing yellow arrow.The algorithm determines the time interval between the successive arrivals of vehicles and computes the corresponding headway for each lane by cycle on a secondby-second basis.Peer-to-peer logic is a necessary step to verify and validate new traffic concepts prior to field-testing and offers the advantage of acquiring and analyzing realtime traffic data coupled with video feed with the benefit of a safe environment.
