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5G NR信号辐射性能及空口测量要点(上) 被引量:1
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作者 钱肇钧 孙宇涛 +2 位作者 梅芳 刘晓普 王治夏 《中国无线电》 2022年第1期38-42,共5页
为满足日益增长的移动通信需求,5G采用了新的信号空中接口技术,称为5G NR。相比4G LTE,5GNR对开场空口信号测量和监测提出了新的要求,带来了新的挑战。因此,如何在开场对在用5GNR基站发射机开展参数测量和干扰监测,便成为一个亟待解决... 为满足日益增长的移动通信需求,5G采用了新的信号空中接口技术,称为5G NR。相比4G LTE,5GNR对开场空口信号测量和监测提出了新的要求,带来了新的挑战。因此,如何在开场对在用5GNR基站发射机开展参数测量和干扰监测,便成为一个亟待解决的问题。本文首先从空口监测的角度梳理了5G基站使用的有源天线、波束赋形、新空口技术,再通过仿真说明了对波束赋形信号和带外发射监测的技术要点,最后通过实际信号阐述了使用门控频谱的监测方法。 展开更多
关键词 5G信号辐射 5G信号分析 5G基站空测量 5G监测
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5G NR信号辐射性能及空口测量要点(下) 被引量:1
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作者 钱肇钧 孙宇涛 +2 位作者 梅芳 刘晓普 王治夏 《中国无线电》 2022年第2期48-51,共4页
为满足日益增长的移动通信需求,5G采用了新的信号空中接口技术,称为5G NR。相比4G LTE,5GNR对开场空口信号测量和监测提出了新的要求,带来了新的挑战。因此,如何在开场对在用5GNR基站发射机开展参数测量和干扰监测,便成为一个亟待解决... 为满足日益增长的移动通信需求,5G采用了新的信号空中接口技术,称为5G NR。相比4G LTE,5GNR对开场空口信号测量和监测提出了新的要求,带来了新的挑战。因此,如何在开场对在用5GNR基站发射机开展参数测量和干扰监测,便成为一个亟待解决的问题。本文首先从空口监测的角度梳理了5G基站使用的有源天线、波束赋形、新空口技术,再通过仿真说明了对波束赋形信号和带外发射监测的技术要点,最后通过实际信号阐述了使用门控频谱的监测方法。 展开更多
关键词 5G信号辐射 5G信号分析 5G基站空测量 5G监测
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基于FDMA(频分多址)技术的空口位置信号模拟装置
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作者 查伟 欧冬秀 《城市轨道交通研究》 北大核心 2023年第12期271-274,279,共5页
目的:为模拟信标与车载信标天线间空口位置信号发生及传输特性,提出了基于FDMA(频分多址)技术的新型空口位置信号模拟装置。方法:介绍了基于FDMA技术的信号传输模式、模拟原理;阐述了基于FDMA技术的新型空口位置信号模拟装置组成及各组... 目的:为模拟信标与车载信标天线间空口位置信号发生及传输特性,提出了基于FDMA(频分多址)技术的新型空口位置信号模拟装置。方法:介绍了基于FDMA技术的信号传输模式、模拟原理;阐述了基于FDMA技术的新型空口位置信号模拟装置组成及各组成部件的功能。结果及结论:该模拟装置可用于轨道交通列车控制系统空口位置信号模拟。该模拟装置继承了FDMA多路多频信号承载的特性,信号频谱范围广,具备全双工上下行信号同步交互的会话机制,在保证多路多频信号高保真度和高同步性的同时,可支持对各路频分多址信号的增益和衰减系数进行灵活处理,可广泛地匹配轨道交通列车控制系统多样式的FDMA空口位置信号接口。 展开更多
关键词 轨道交通 列车控制系统 位置信号 模拟装置
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基于VISSIM仿真的多岔路口信号灯智慧控制方法
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作者 任慧 《武汉轻工大学学报》 2020年第4期71-76,共6页
为提升多岔路口的通行能力,解决当前已有方法存在的行程延误时间和车辆排队时间较长等问题,提出了一种基于VISSIM仿真的多岔路口信号灯智慧控制方法。从我国混合交通流的特点出发,调查多岔路口的交通流量以及延误情况等,采用交通流理论... 为提升多岔路口的通行能力,解决当前已有方法存在的行程延误时间和车辆排队时间较长等问题,提出了一种基于VISSIM仿真的多岔路口信号灯智慧控制方法。从我国混合交通流的特点出发,调查多岔路口的交通流量以及延误情况等,采用交通流理论分析多岔路口交通流通情况,通过交通模拟软件VISSIM进行仿真模拟,找出拥堵路口;然后对其进行配时改进,获取最佳多岔路口信号灯智慧控制方案。最后进行仿真实验测试,实验结果表明,所提方法能够有效降低延误时间,提升城市多岔路口的通行能力。 展开更多
关键词 VISSIM仿真 多岔路信号 智慧控制 优化
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排队长度模型比较及动态方法研究 被引量:10
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作者 周学农 《交通运输系统工程与信息》 EI CSCD 2006年第1期91-95,共5页
使用长沙市道路交通状况的真实数据,对比分析了国外多个经典排队长度模型的计算结果,并在结合当地交通特性的基础上,对SIGNAL94进行改进,建立了符合本地实际交通状况的排队长度优化模型.同时,在利用时间平滑技术减少交通流随机性对计算... 使用长沙市道路交通状况的真实数据,对比分析了国外多个经典排队长度模型的计算结果,并在结合当地交通特性的基础上,对SIGNAL94进行改进,建立了符合本地实际交通状况的排队长度优化模型.同时,在利用时间平滑技术减少交通流随机性对计算精度影响的过程中,发现以15分钟作为平滑参数,能够进一步降低优化模型的跟踪误差. 展开更多
关键词 排队长度 信号口 饱和 动态模型
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Characteristics and risk of violation behavior of non-motorists at signalized intersections 被引量:6
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作者 赵星 任刚 +2 位作者 杜轩 王鹏 王卫杰 《Journal of Southeast University(English Edition)》 EI CAS 2011年第4期423-429,共7页
Aiming at prevalent violations of non-motorists at urban intersections in China, this paper intends to clarify the characteristics and risks of non-motorist violations at signalized intersections through questionnaire... Aiming at prevalent violations of non-motorists at urban intersections in China, this paper intends to clarify the characteristics and risks of non-motorist violations at signalized intersections through questionnaires and video recordings, which may serve as a basis for non-motorized vehicle management. It can help improve the traffic order and enhance the degree of safety at signalized intersections. To obtain the perception information, a questionaire survey on the Internet was conducted and 972 valid questionnaires were returned. It is found that academic degree contributes little to non-motorist violations, while electrical bicyclists have a relatively higher frequency of violations compared with bicyclists. The video data of 18 228 non-motorist behaviors indicate that the violation rate of all non-motorists is 26.5%; the number of conflicts reaches 1 938, among which violation conflicts account for 66.8%. The study shows that the violation rates and the violation behavior at three types of surveyed intersections are markedly different. It is also concluded that the conflict rates and the violation rates are positively correlated. Furthermore, signal violation, traveling in the wrong direction, and overspeeding to cross the intersection are the most dangerous among traffic violation behaviors. 展开更多
关键词 traffic violation behavior traffic safety non- motorist signal intersection
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Method for pedestrian signal timing at signalized intersections 被引量:3
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作者 王京元 王炜 《Journal of Southeast University(English Edition)》 EI CAS 2006年第4期564-569,共6页
The pedestrian timing at signalized intersections is studied aiming at the problems of the inconsistency of the vehicular and pedestrian timing requirements and the insufficiency of pedestrian clearance. Based on the ... The pedestrian timing at signalized intersections is studied aiming at the problems of the inconsistency of the vehicular and pedestrian timing requirements and the insufficiency of pedestrian clearance. Based on the formulae of WALK and flashing DON'T WALK (FDW) in the highway capacity manual (HCM), the relationship between pedestrian signal indications and vehicular signal indications is discussed using the theory of traffic flow. Then, methods of pedestrian timing for different cases are established, particularly the methods of the pedestrian green adjustment. Ways of pedestrian crossing are analyzed for roadways with different forms and widths of the median island. The sampling values of calculation parameters are studied, and the recommended formulae of pedestrian timing for different conditions are presented. 展开更多
关键词 signalized intersection pedestrian signal timing WALK indication flashing DON'T WALK indication
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NSGA-Ⅱ based traffic signal control optimization algorithm for over-saturated intersection group 被引量:8
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作者 李岩 过秀成 +1 位作者 陶思然 杨洁 《Journal of Southeast University(English Edition)》 EI CAS 2013年第2期211-216,共6页
In order to improve the efficiency of traffic signal control for an over-saturated intersection group, a nondominated sorting genetic algorithm Ⅱ(NSGA-Ⅱ) based traffic signal control optimization algorithm is prop... In order to improve the efficiency of traffic signal control for an over-saturated intersection group, a nondominated sorting genetic algorithm Ⅱ(NSGA-Ⅱ) based traffic signal control optimization algorithm is proposed. The throughput maximum and average queue ratio minimum for the critical route of the intersection group are selected as the optimization objectives of the traffic signal control for the over-saturated condition. The consequences of the efficiency between traffic signal timing plans generated by the proposed algorithm and a commonly utilized signal timing optimization software Synchro are compared in a VISSIM signal control application programming interfaces (SCAPI) simulation environment by using real filed observed traffic data. The simulation results indicate that the signal timing plan generated by the proposed algorithm is more efficient in managing oversaturated flows at intersection groups, and, thus, it has the capability of optimizing signal timing under the over-saturated conditions. 展开更多
关键词 traffic signal control optimization algorithm intersection group over-saturated status NSGA-H algorithm
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Multi-phase signal setting and capacity of signalized intersection 被引量:1
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作者 常玉林 崔益波 张鹏 《Journal of Southeast University(English Edition)》 EI CAS 2009年第1期123-127,共5页
A capacity model of multi-phase signalized intersections is derived by a stopping-line method. It is simplified with two normal situations: one situation involves one straight lane and one left-turn lane; the other s... A capacity model of multi-phase signalized intersections is derived by a stopping-line method. It is simplified with two normal situations: one situation involves one straight lane and one left-turn lane; the other situation involves two straight lanes and one left-turn lane. The results show that the capacity is mainly relative to signal cycle length, phase length, intersection layout and following time. With regard to the vehicles arrival rates, the optimal model is derived based on each phase's remaining time balance, and it is solved by Lagrange multipliers. Therefore, the calculation models of the optimal signal cycle length and phase lengths are derived and simplified. Compared to the existing models, the proposed model is more convenient and practical. Finally, a practical intersection is chosen and its signal cycles and phase lengths are calculated by the proposed model. 展开更多
关键词 traffic engineering INTERSECTION multi-phase signal timing Lagrange multipliers OPTIMIZATION
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Analytical method of minimum spacing of signalized intersections on bidirectional two-lane highways
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作者 马永锋 袁黎 张文波 《Journal of Southeast University(English Edition)》 EI CAS 2015年第4期547-552,共6页
In order to improve the smoothness of traffic flow on bidirectional two-lane highways, an analytical method is proposed to optimize the minimum spacing of the signalized intersections. The minimum signal spacing is de... In order to improve the smoothness of traffic flow on bidirectional two-lane highways, an analytical method is proposed to optimize the minimum spacing of the signalized intersections. The minimum signal spacing is determined by two parts, including the necessary distance for stabilizing the traffic flow after it passes through the signalized intersections and the length of the upstream functional area of intersection. For the former, based on the platoon dispersion theory, the stable distance determination problem of traffic flow is studied and a model of dispersion degrees varying with the distance from the upstream intersection is presented, in which the time headway is intended to yield the shifted negative exponential distribution. The parameters of the model for medal and collector highways are estimated respectively based on the field data. Then, the section at which the slope of dispersion degree curve equals -0.1 is regarded as the beginning of the dispersion stable state. The length of the intersection upstream functional area is determined by three parts, including the distance traveled during perception-reaction time, the distance traveled while a driver decelerates to a stop, and the queue storage length. Based on the above procedures, the minimum signal spacing of each highway category is proposed. 展开更多
关键词 HIGHWAY signalized intersection SPACING platoon dispersion
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Study on the model of pedestrian cross-time in signalized intersection
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作者 徐良杰 《Journal of Southeast University(English Edition)》 EI CAS 2008年第4期513-516,共4页
For studying the law of pedestrian cross-time in the signalized intersection, based on gap theory, a probability chorological discipline model of crossing pedestrians is built based on the observed data. Moreover, the... For studying the law of pedestrian cross-time in the signalized intersection, based on gap theory, a probability chorological discipline model of crossing pedestrians is built based on the observed data. Moreover, the number of pedestrians passing through in a critical gap is estimated under different conditions by three models. Then the models of pedestrian crosswalk average time, the 85th percentile pedestrian cross-time and the 90th percentile pedestrian cross-time are deduced. By quantitative analyses and the exemplification of the models, the main correlative factors acting on pedestrian cross-time are found, including the length of the crosswalk, the probability of the time-headway being less than the critical gap and the number of the turned motor vehicles in the intersection. The results indicate that the estimated errors of the models are less than 5%. 展开更多
关键词 signalized intersection CONFLICT critical gap pedestrian cross-time
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屏蔽线长度对浪涌测试结果影响的研究
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作者 李泽强 卢新科 《安全与电磁兼容》 2022年第1期89-91,共3页
针对当前很多实验室对双端接地屏蔽线信号口浪涌测试线长要求不严格的现状,探究屏蔽线测试线长对浪涌测试结果的影响。首先对GB/T 17626.5-2019中双端接地屏蔽线信号口浪涌测试方法进行了梳理,然后通过设计具体的验证试验得到了线缆长... 针对当前很多实验室对双端接地屏蔽线信号口浪涌测试线长要求不严格的现状,探究屏蔽线测试线长对浪涌测试结果的影响。首先对GB/T 17626.5-2019中双端接地屏蔽线信号口浪涌测试方法进行了梳理,然后通过设计具体的验证试验得到了线缆长度和试验严酷度的对比统计数据,最后结合对屏蔽层和芯线之间的耦合机理和试验数据分析得出了浪涌信号线测试时线缆越长试验等级越严酷的结论,对规范双端接地屏蔽线信号口浪涌测试有一定的指导意义。 展开更多
关键词 浪涌试验 屏蔽线信号口 线长 耦合
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Dynamic signal control for at-grade intersections under preliminary autonomous vehicle environment 被引量:3
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作者 LUO Si-da ZHANG Shuai 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第4期893-904,共12页
Autonomous vehicle technology will transform fundamentally urban traffic systems.To better enhance the coming era of connected and autonomous vehicles,effective control strategies that interact wisely with these intel... Autonomous vehicle technology will transform fundamentally urban traffic systems.To better enhance the coming era of connected and autonomous vehicles,effective control strategies that interact wisely with these intelligent vehicles for signalized at-grade intersections are indispensable.Vehicle-to-infrastructure communication technology offers unprecedented clues to reduce the delay at signalized intersections by innovative information-based control strategies.This paper proposes a new dynamic control strategy for signalized intersections with vehicle-to-signal information.The proposed strategy is called periodic vehicle holding(PVH)strategy while the traffic signal can provide information for the vehicles that are approaching an intersection.Under preliminary autonomous vehicle(PAV)environment,left-turning and through-moving vehicles will be sorted based on different information they receive.The paper shows how PVH reorganizes traffic to increase the capacity of an intersection without causing severe spillback to the upstream intersection.Results show that PVH can reduce the delay by approximately 15%at a signalized intersection under relatively high traffic demand. 展开更多
关键词 dynamic traffic control vehicle-to-signal signalized intersection preliminary autonomous vehicle environment
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Optimal allocation model of signalized intersections with dynamic use of exit lanes for left turn 被引量:3
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作者 Qu Zhaowei Qi Xingzu +3 位作者 Chen Yongheng Bai Qiaowen Tao Chuqing Liu Fanghong 《Journal of Southeast University(English Edition)》 EI CAS 2020年第2期213-219,共7页
In order to improve the operational efficiency of heavy left-turn demand intersections,an optimal allocation model of an intersection with dynamic use of exit lanes for left turns(EFL)is proposed.The constraints of se... In order to improve the operational efficiency of heavy left-turn demand intersections,an optimal allocation model of an intersection with dynamic use of exit lanes for left turns(EFL)is proposed.The constraints of setting EFL are analyzed,including the number and length of reverse variable lanes,flow direction constraints,and signal constraints,etc.The constraints and control variables are combined in a unified framework for simultaneous optimization.The objective functions are defined as the average delay and left-turn capacity of an intersection.The model is solved by a non-dominated genetic algorithm(NSGA-Ⅱ).The results show that after the optimal allocation of EFL,the average vehicle delays of the intersection can be reduced by 14.9%and left-turn capacity can be increased by 19.3%.The effectiveness of the optimal allocation model of EFL is demonstrated. 展开更多
关键词 traffic engineering exit lane for left turn signaled intersection multi-objective optimization
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Vehicle actuation based short-term traffic flow prediction model for signalized intersections 被引量:8
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作者 SUN Jian ZHANG Lun 《Journal of Central South University》 SCIE EI CAS 2012年第1期287-298,共12页
Traffic flow prediction is an important component for real-time traffic-adaptive signal control in urban arterial networks.By exploring available detector and signal controller information from neighboring intersectio... Traffic flow prediction is an important component for real-time traffic-adaptive signal control in urban arterial networks.By exploring available detector and signal controller information from neighboring intersections,a dynamic data-driven flow prediction model was developed.The model consists of two prediction components based on the signal states(red or green) for each movement at an upstream intersection.The characteristics of each signal state were carefully examined and the corresponding travel time from the upstream intersection to the approach in question at the downstream intersection was predicted.With an online turning proportion estimation method,along with the predicted travel times,the anticipated vehicle arrivals can be forecasted at the downstream intersection.The model performance was tested at a set of two signalized intersections located in the city of Gainesville,Florida,USA,using the CORSIM microscopic simulation package.Analysis results show that the model agrees well with empirical arrival data measured at 10 s intervals within an acceptable range of 10%-20%,and show a normal distribution.It is reasonably believed that the model has potential applicability for use in truly proactive real-time traffic adaptive signal control systems. 展开更多
关键词 adaptive signal control least-squared estimation microscopic simulation travel flow prediction urban arterials
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Compact passing algorithm for signalized intersection management based on vehicular network 被引量:1
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作者 Bian Chentong Yin Guodong +1 位作者 Xu Liwei Zhang Ning 《Journal of Southeast University(English Edition)》 EI CAS 2019年第1期103-110,共8页
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
关键词 intersection management signalized intersection vehicular network compact passing phase timing
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Signal timing optimization model based on dual-ring phase scheme for roundabout 被引量:4
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作者 马万经 谢涵洲 +2 位作者 白玉 赵靖 杨晓光 《Journal of Central South University》 SCIE EI CAS 2013年第2期563-571,共9页
A signal optimization model for roundabout was control concept were used to eliminate the conflict points proposed based on dual-ring scheme and two stop lines for left turns and weaving sections at a roundabout. A cy... A signal optimization model for roundabout was control concept were used to eliminate the conflict points proposed based on dual-ring scheme and two stop lines for left turns and weaving sections at a roundabout. A cycle length minimization problem was considered to generate optimal signal timings for roundabout, and a set of constraints to ensure feasibility and safety of the resulting optimal signal settings were proposed. Extensive experimental analyses in comparison with signalized intersection reveal that the proposed model is quite promising for application in design of roundabout signals, and the minimum cycle length can decrease from 186 s to 79 s while the capacity increases from 8 682 pcu/h to 9 011 pcu/h under high demand scenario. Sensitivity analysis with respect to the system performance show that the lane assignment plan, number of circulatory lanes and left turn ratio are three critical factors which have dominate impacts on performance of signalized roundabout 展开更多
关键词 signalized roundabout dual-ring phase single timing optimization left-turn movement
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Mixed Traffic Flow Capacity of More Major Lanes Unsignalized Intersection 被引量:1
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作者 TIAN Xin-xian 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第3期462-469,共8页
Highway capacity is defined as maximum volume of traffic flow through the particular highway section under given traffic conditions, road conditions and so on. Highway construction and management is judged by capacity... Highway capacity is defined as maximum volume of traffic flow through the particular highway section under given traffic conditions, road conditions and so on. Highway construction and management is judged by capacity standard. The reasonable scale and time of highway construction, rational network structure and optimal management mode of highway network can be determined by analyzing the fitness between capacity and traffic volume. All over the world, highway capacity is studied to different extent in different country. Based on the gap acceptance theory, the mixed traffic flow composed of two representative vehicle types heavy and light vehicles is analyzed with probability theory. Capacity model of the minor mixed traffic flows crossing m major lanes, on which the traffic flows fix in with M3 distributed headway, on the unsignalized intersection is set up, and it is an extension of minor lane capacity theory for one vehicle-type and one major-lane traffic flow. 展开更多
关键词 HEADWAY gap acceptance mixed traffic flow highway capacity
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Effects of flashing green on driver's stop/go decision at signalized intersection 被引量:2
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作者 沈家军 王炜 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第2期771-778,共8页
The primary objective of this work is to explore how drivers react to flashing green at signalized intersections. Through video taping and data procession based on photogrammetry, the operating speeds of vehicles befo... The primary objective of this work is to explore how drivers react to flashing green at signalized intersections. Through video taping and data procession based on photogrammetry, the operating speeds of vehicles before and after the moment when flashing green started was compared using paired-samples T-test. The critical distances between go and stop decisions was defined through cumulative percentage curve. The boundary of dilemma zone was determined by comparing stop distance and travel distance.Amber-running violation was analyzed on the basis of the travel time to the stop line. And finally, a logistic model for stop and go decisions was constructed. The results shows that the stopping ratios of the first vehicles of west-bound and east-bound approaches are 41.3% and 39.8%, respectively; the amber-light running violation ratios of two approaches are 31.6% and 25.4%, respectively;the operating speed growth ratios of first vehicles selecting to cross intersection after the moment when flashing green started are26.7% and 17.7%, respectively; and the critical distances are 48 m and 46 m, respectively, which are close to 44 m, the boundary of dilemma zone. The developed decision models demonstrate that the probability of go decision is higher when the distance from the stop line is shorter or operating speed is higher. This indicates that flashing green is an effective way to enhance intersection safety,but it should work together with a strict enforcement. In addition, traffic signs near critical distance and reasonable speed limitation are also beneficial to the safety of intersections. 展开更多
关键词 signalized intersections flashing green critical distance dilemma zone amber-running violation logistic decision model
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Effects of behavioral characteristics of taxi drivers on safety and capacity of signalized intersections 被引量:2
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作者 徐铖铖 刘攀 +2 位作者 王炜 蒋璇 陈昱光 《Journal of Central South University》 SCIE EI CAS 2014年第10期4033-4042,共10页
Comparative analyses were conducted to compare the effects of the behavioral characteristics of the drivers of taxis and private cars on the capacity and safety of signalized intersections. Data were collected at sixt... Comparative analyses were conducted to compare the effects of the behavioral characteristics of the drivers of taxis and private cars on the capacity and safety of signalized intersections. Data were collected at sixteen signalized intersections in the Nanjing area in China. The risk-taking behaviors of the drivers of taxis and private cars were compared. The results suggest that 19.9% of taxi drivers have committed at least one of the identified risky behaviors, which is 2.37 times as high as that of the drivers of private cars(8.4%). The traffic conflicts technique was used to estimate the safety effects of taxis and private cars. The overall conflict rate for taxis is 21.4% higher than that for private cars, implying that taxis are more likely to be involved in conflicts. Almost all of the identified traffic conflicts can be attributed to certain levels of risk-taking behaviors committed by either taxi drivers or the drivers of private cars, and taxi drivers are more likely to be at fault in a conflict. Failure to yield to right-of-way and improper lane change is the leading causes of the conflicts in which taxis are at-fault. The research team further studied the effects of taxis on the queue discharge characteristics at signalized intersections. The results show that the presence of taxis significantly reduces both start-up lost time and saturation headways. The effects of taxis on saturation flow rates are dependent on the proportion of taxis in the discharge flow, and the saturation flow rates increase with the increase in the proportion of taxis. The adjustment factors for various proportions of taxis for different turning movements are then calculated to quantitatively evaluate the effects of taxis on the capacity of signalized intersections. 展开更多
关键词 TAXI private car SAFETY capacity signalized intersection
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