共查询到20条相似文献,搜索用时 140 毫秒
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采用元胞自动机模型研究了具有信号灯控制的主道为双车道的入匝道系统交通流特性.将信号灯设置在入匝道口处,通过信号灯来引导主道和匝道上的车辆通行.分析了信号灯控制对主道与匝道的车流量、系统通行能力以及入匝道口处的车流平均速度的影响.通过相图比较,说明信号灯控制的双车道入匝道系统能模拟出比信号灯控制的单车道入匝道系统更加符合实际的交通流特性.与姜锐提出的模型[Jiang R 2003 J. Phys. A 36 11713]结果相比,信号灯控制下的匝道系统的交通流状态得到改善并且道路通行能力有所提
关键词:
交通流
元胞自动机
入匝道系统
信号灯 相似文献
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利用唐等人提出的考虑事故概率的交通流模型[Tang T Q, Huang H J, Xu G 2008 Physica A 387 6845]研究事故发生地点对冲击波和稀疏波的影响,其数值计算结果表明,该模型可以如实地刻画事故对这两种交通波的影响,但这种影响与事故发生地点密切相关.
关键词:
交通事故
冲击波
稀疏波 相似文献
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采用元胞自动机模型研究信号灯路口的交通流特性,系统地分析了与性别、驾驶经验、性格等驾驶员属性相关的驾驶行为对交通流的影响.数值模拟发现,技术生疏或紧张驾驶、急躁行驶等驾驶行为更易引发自由流到阻塞流的相变,是路口通行低效率及事故隐患的重要原因,信号周期是影响流量与个人通行时间公平的主要因素. 相似文献
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对超音叶栅极限特征线以前流场特征的分析表明,外伸波系导致的总压损失主要受无量纲前缘半径(R_(le))和来流马赫数(Ma_(∞))影响。通过对理论解的简化,本文建立了计算外伸波系引起的总压损失的经验关系式。相比以前的损失模型,该关系式在0.0074R_(le)0.0148,1.1Maa_(∞)2.1时具有更高的精度。针对超音叶栅由未启动状态向启动状态转变的过渡状态,在分析前缘内伸波的激波形态时,本文认为采用内伸波波阵面和流道内流线始终垂直的处理方式更加符合内伸波波后亚音的流动特征,并依此建立了过渡状态下内伸波损失计算模型。通过和已有模型估算结果以及实验结果的对比可知,在过渡状态下,采用本文提出的内伸波损失模型,能够准确计算超音叶栅的前缘内伸激波损失。 相似文献
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通过线性稳定性分析,得到了多前车速度差模型的稳定性条件, 并发现通过调节多前车信息,使交通流的稳定区域明显扩大. 通过约化摄动方法 研究了该模型的非线性动力学特性:在稳定流区域,得到了描述密度波的Burgers方程;在交 通流的不稳定区域内,在临界点附近获得了描述车头间距的修正的Korteweg-de Vries (modified Korteweg-de Vries, mKdV)方程; 在亚稳态区域内,在中性稳定曲线附近获得了描述车头间距 的KdV方程. Burgers的孤波解、mKdV方程的扭结-反扭结波解及KdV方程的 孤波解描述了交通流堵塞现象. 相似文献
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以Barkley模型为研究对象, 研究了在时空调制作用下螺旋波时空动力学行为特性. 发现在适当的调制参数的作用下, 能够在同一系统中同时观察到漫游螺旋波与旅行螺旋波. 通过数值模拟研究分析, 给出了能产生漫游螺旋波与旅行螺旋波共存现象的潜在机理, 并详细讨论了在Barkley 模型中要产生这种共存现象的两个必要条件.
关键词:
时空调制
漫游螺旋波
旅行螺旋波 相似文献
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In this paper, we present a new macro model which involves the effects that the probability of traffic interruption has on the car-following behavior through formulating the inner relationship between micro and macro variables. Linear stability analysis shows that consideration of the traffic interruption probability can improve the stability of traffic flow if and only if the drivers’ reactive time required for adjusting their acceleration based on the traffic interruption probability p is not greater than that one based on the non-interruption probability 1−p. Numerical results verify that the new model can be used to analyze the effects of traffic interruption probability and traffic interruption on shock, rarefaction wave, small perturbation and uniform flow. The model has been applied in reproducing some complex traffic phenomena resulted by some traffic interruptions (e.g., signal light, pedestrian and tolling station). 相似文献
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为了更加客观地描述实际的车辆跟驰行为, 在优化速度模型的基础上, 通过引入横向分离参数并提出超车期望和虚拟前车的概念, 建立了考虑横向分离与超车期望的车辆跟驰模型.对模型进行线性稳定性分析, 得到了模型稳定性条件, 发现车辆横向分离、超车期望和虚拟前车的位置的增加, 在车流密度较小、车速较快的情况下, 使得交通流稳定区域增大, 但在车流密度较大、车速较慢的情况下, 反而使得交通流稳定区域减小.数值模拟结果验证了模型稳定性分析的结果, 表明在交通瓶颈处等交通流密度较大、运行缓慢的区域, 为抑制交通拥堵, 应该限制车辆的横向偏移和超车行为的发生.
关键词:
交通流
车辆跟驰模型
横向分离
超车期望 相似文献
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In this paper, we present a new car-following model by taking into
account the effects of the traffic interruption probability on the
car-following behaviour of the following vehicle. The stability
condition of the model is obtained by using the linear stability
theory. The modified Korteweg--de Vries (KdV) equation is constructed
and solved, and three types of traffic flows in the
headway sensitivity space---stable, metastable, and unstable---are
classified. Both the analytical and simulation results show that the
traffic interruption probability indeed has an influence on driving
behaviour, and the consideration of traffic interruption probability
in the car-following model could stabilize traffic flow. 相似文献
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In this paper the new continuum traffic flow model proposed by Jiang
{\it et al is developed based on an improved car-following model, in
which the speed gradient term replaces the density gradient term in
the equation of motion. It overcomes the wrong-way travel which
exists in many high-order continuum models. Based on the continuum
version of car-following model, the condition for stable traffic flow
is derived. Nonlinear analysis shows that the density fluctuation in
traffic flow induces a variety of density waves. Near the onset of
instability, a small disturbance could lead to solitons determined by
the Korteweg--de-Vries (KdV) equation, and the soliton solution is
derived. 相似文献
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Modeling the heterogeneous traffic flow considering the effect of self-stabilizing and autonomous vehicles 下载免费PDF全文
With the increasing maturity of automatic driving technology,the homogeneous traffic flow will gradually evolve into the heterogeneous traffic flow,which consists of human-driving and autonomous vehicles.To better study the characteristics of the heterogeneous traffic system,this paper proposes a new car-following model for autonomous vehicles and heterogeneous traffic flow,which considers the self-stabilizing effect of vehicles.Through linear and nonlinear methods,this paper deduces and analyzes the stability of such a car-following model with the self-stabilizing effect.Finally,the model is verified by numerical simulation.Numerical results show that the self-stabilizing effect can make the heterogeneous traffic flow more stable,and that increasing the self-stabilizing coefficient or historical time length can strengthen the stability of heterogeneous traffic flow and alleviate traffic congestion effectively.In addition,the heterogeneous traffic flow can also be stabilized with a higher proportion of autonomous vehicles. 相似文献
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This Letter develops a new staggered car-following model taking into consideration lateral separation effects. Time-to-collision, calculated using visual angle variables, is introduced to describe the lateral separation distance and improve the optimal velocity model. The analytical and numerical results show that the stability of traffic flow can gradually be enhanced with the increase of lateral separation effects. The asymmetry property of traffic flow is also investigated using the new model. The results imply that incorporating lateral separation effects into the car-following model leads to the suppression of traffic jams and greatly enhances the realism of the model. 相似文献
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In this paper the new continuum traffic flow model proposed by Jiang et al is developed based on an improved car-following model, in which the speed gradient term replaces the density gradient term in the equation of motion. It overcomes the wrong-way travel which exists in many high-order continuum models. Based on the continuum version of car-following model, the condition for stable traffic flow is derived. Nonlinear analysis shows that the density fluctuation in traffic flow induces a variety of density waves. Near the onset of instability, a small disturbance could lead to solitons determined by the Korteweg-de-Vries (KdV) equation, and the soliton solution is derived. 相似文献
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基于Newell跟驰模型,建立考虑车与车互联(vehicle-to-vehicle,V2V)通讯技术的单车道跟驰模型.根据V2V技术的特征,引入参数α以表征驾驶员在收到V2V技术所提供的实时交通信息后的提前反应程度.根据线性稳定分析方法,得到V2V跟驰模型的中性稳定条件.通过计算机的模拟,研究V2V技术对交通流运行的影响,分析小扰动下V2V跟驰模型对参数变化的敏感性,研究不同α取值下交通流密度波及迟滞回环的变化.研究发现:1)与全速度差跟驰模型相比,在引入V2V后,交通流在加速起步、减速刹车及遇到突发事件时,车辆运行的安全性和舒适性均得到不同程度的提升;2)V2V跟驰模型对参数α及T的变化较为敏感,且在交通流较为拥堵时,V2V技术的引入可以提升交通流的平均速度;3)参数α的增大、T的减小可以有效提升V2V跟驰模型在不同交通环境下的运行稳定性.由于可以实时地获取交通流运行的状态并针对性地改变车辆自身的运行,V2V交通流跟驰模型提升了交通流运行的稳定性. 相似文献
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The car-following behavior can be influenced by its driver’s backward-looking effect.Especially in traffic congestion,if vehicles adjust the headway by considering backward-looking effect,the stability of traffic flow can be enhanced.A model of car-following behavior considering backward-looking effect was built using visual information as a stimulus.The critical stability conditions were derived by linear and nonlinear stability analyses.The results of parameter sensitivity analysis indicate that the stability of traffic flow was enhanced by considering the backward-looking effect.The spatiotemporal evolution of traffic flow of different truck ratios and varying degrees of backward-looking effect was determined by numerical simulation.This study lays a foundation for exploring the complex feature of car-following behavior and making the intelligent network vehicles control rules more consistent with human driver habits. 相似文献