To satisfy the multiple priority requests from buses that arrive at different phases within a small time window, a multi-phase bus signal priority (MPBSP) strategy is developed. The proximity principle is brought fo...To satisfy the multiple priority requests from buses that arrive at different phases within a small time window, a multi-phase bus signal priority (MPBSP) strategy is developed. The proximity principle is brought forward to settle the conflicts among multiple priority requests and arrange the optimal priority sequence. To avoid over saturation of the intersection, a conditional MPBSP algorithm that adopts early green and green extension strategies is developed to give priority to the bus with the highest priority level when green time that each phase runs makes its saturation degree not larger than 0. 95. Finally, the algorithm is tested in the VISSIM environment and compared with the normal signal timing algorithm. Sensitive analysis of the number of priority phases, bus demand, and volume to capacity ratios are conducted to quantify their impacts on the benefits of the MPBSP. Results show that the MPBSP strategy can effectively reduce bus delays, and with the increase in the number of priority phases, the reduction range of bus delays also increases.展开更多
To improve the traffic efficiency at signalized intersections, a compact passing algorithm is proposed based on a vehicular network. Its basic principle is that several waiting vehicles after the stop line of the cons...To improve the traffic efficiency at signalized intersections, a compact passing algorithm is proposed based on a vehicular network. Its basic principle is that several waiting vehicles after the stop line of the considered intersection should simultaneously start in green periods. Thus, more vehicles can pass the intersection in a green period. Then, the having passed vehicles should follow the planned trajectories to enlarge their longitudinal clearances. Phase timing is not considered in the compact passing algorithm, and therefore, the proposed compact passing algorithm can be combined with other algorithms on phase timing to further improve their performances. Several simulations were designed and performed to verify the performance of the proposed algorithm. The simulation results show that the proposed algorithm can increase the number of completed vehicles and decrease the travel time in the signalized intersections managed by fixed-time and vehicle actuated algorithms, which indicates that the proposed algorithm is effective for improving the traffic efficiency at common signalized intersections.展开更多
We examine the traffic lights regime to enable the fastest overall approach to a city for a specific case. The case involves a traffic light where one continues on the main road, into which additional cars are enterin...We examine the traffic lights regime to enable the fastest overall approach to a city for a specific case. The case involves a traffic light where one continues on the main road, into which additional cars are entering at the light. At this intersection an alternative route begins, which is longer but into which no additional cars are entering. To keep the total number of vehicles constant, we subtract on the main road far from the intersection, the same number of cars as were added at the intersection. In addition to checking different densities we check also the influence of changes in the number of cars which were added. We calculate the Fourier transform of the average on each traffic light cycles of the velocity on the main road and bypass. We obtained different results for different cases. All the cases can be written as 1/fa .展开更多
With the advantages of long lifetime, high lighting effect and non-pollution, LED lighting has taken a leading role in the lighting sector. LED street and tunnel lights have no unified product interface, so the produc...With the advantages of long lifetime, high lighting effect and non-pollution, LED lighting has taken a leading role in the lighting sector. LED street and tunnel lights have no unified product interface, so the products of different enterprises cannot interchange with each other, restraining the development of the whole industry due to the large-scale production problem. The alliance standard CSA 016-2013 has been approved as a national standard project, paving the way for the orderly development of LED industry. Interpreting the CSA 016 standard, the paper expounds on the technical requirements for interchangeable interface in the optical, mechanical, electrical and thermal aspects.展开更多
基金The National High Technology Research and Development Program of China(863 Program)(No.2011AA110304)the National Natural Science Foundation of China(No.50908100)Graduate Innovation Fund of Jilin University(No.20111044)
文摘To satisfy the multiple priority requests from buses that arrive at different phases within a small time window, a multi-phase bus signal priority (MPBSP) strategy is developed. The proximity principle is brought forward to settle the conflicts among multiple priority requests and arrange the optimal priority sequence. To avoid over saturation of the intersection, a conditional MPBSP algorithm that adopts early green and green extension strategies is developed to give priority to the bus with the highest priority level when green time that each phase runs makes its saturation degree not larger than 0. 95. Finally, the algorithm is tested in the VISSIM environment and compared with the normal signal timing algorithm. Sensitive analysis of the number of priority phases, bus demand, and volume to capacity ratios are conducted to quantify their impacts on the benefits of the MPBSP. Results show that the MPBSP strategy can effectively reduce bus delays, and with the increase in the number of priority phases, the reduction range of bus delays also increases.
基金The National Natural Science Foundation of China(No.51575103,U1664258)the National Key Research and Development Program of China(No.2016YFB0100906,2016YFD0700905)+2 种基金Six Talent Peaks Project in Jiangsu Province(No.2014-JXQC-001)Fundamental Research Funds for the Central Universities(No.2242016K41056)the Southeast University Excellent Doctor Degree Thesis Training Fund(No.YBJJ1703)
文摘To improve the traffic efficiency at signalized intersections, a compact passing algorithm is proposed based on a vehicular network. Its basic principle is that several waiting vehicles after the stop line of the considered intersection should simultaneously start in green periods. Thus, more vehicles can pass the intersection in a green period. Then, the having passed vehicles should follow the planned trajectories to enlarge their longitudinal clearances. Phase timing is not considered in the compact passing algorithm, and therefore, the proposed compact passing algorithm can be combined with other algorithms on phase timing to further improve their performances. Several simulations were designed and performed to verify the performance of the proposed algorithm. The simulation results show that the proposed algorithm can increase the number of completed vehicles and decrease the travel time in the signalized intersections managed by fixed-time and vehicle actuated algorithms, which indicates that the proposed algorithm is effective for improving the traffic efficiency at common signalized intersections.
文摘We examine the traffic lights regime to enable the fastest overall approach to a city for a specific case. The case involves a traffic light where one continues on the main road, into which additional cars are entering at the light. At this intersection an alternative route begins, which is longer but into which no additional cars are entering. To keep the total number of vehicles constant, we subtract on the main road far from the intersection, the same number of cars as were added at the intersection. In addition to checking different densities we check also the influence of changes in the number of cars which were added. We calculate the Fourier transform of the average on each traffic light cycles of the velocity on the main road and bypass. We obtained different results for different cases. All the cases can be written as 1/fa .
文摘With the advantages of long lifetime, high lighting effect and non-pollution, LED lighting has taken a leading role in the lighting sector. LED street and tunnel lights have no unified product interface, so the products of different enterprises cannot interchange with each other, restraining the development of the whole industry due to the large-scale production problem. The alliance standard CSA 016-2013 has been approved as a national standard project, paving the way for the orderly development of LED industry. Interpreting the CSA 016 standard, the paper expounds on the technical requirements for interchangeable interface in the optical, mechanical, electrical and thermal aspects.