道路交叉口车流检测策略及排队统计方法研究

基于3组道路交叉口交通信息检测器的布设,可实现对交叉口交通流的运行状态信息检测.研究车队头车的特征、判断逻辑和方法,并分析车队尾车的判断逻辑和车队追加的方法,进而提出排队统计开始时刻、排队统计策略,以及排队算法,力求获得较为准确的排队数据.车队检测方法、路口排队统计方法和排队消散方法将为交通控制策略提供信息和技术基础.     

无信号交叉口交通流有序运行实现方法研究

为改善无信号交叉口交通运行现状,基于自然排队思想,采用路中时间提醒装置使驾驶员获取无信号交叉口通行信息,对车速进行主动调整,达到自然排队的效果,在交叉口形成有序的交通流.运用不完全停车理论分析了此种方法对延误的降低,同时剖析了自然排队对交叉口交通的改善.实施方法的采取可以显著改善无信号交叉口的交通秩序,提高其通行能力.     

基于三检测器的多车道车辆排队模型

针对交通拥堵问题,提出了基于三检测器原理的多车道强交通流和弱交通流模型,解决了不同情况下交通拥挤的车辆当量排队长度计算问题,通过与交通波模型的对比分析,结果表明所提模型结果更加准确。同时,模型准确确定了车辆排队长度与车流量等影响因素之间的关系,为交通疏导确立了人工干预的时机。     

宿州市二徐路南段干道绿波控制研究

通过对宿州市二徐路南段三个连续的交叉口进行实地调查,交通"红波带"现象尤为明显,一路红灯干扰着城市道路的顺畅通行。为了保证二徐路主要路线的畅通,利用绿波带控制模式协调控制干线交通。综合考虑优化前的实际交通量、信号灯控制方案以及相序相位的设置情况,运用VISSIM微观仿真软件对优化前后的机动车延误时间以及路段排队长度进行对比评价,优化后的车辆延误时间自南至北降低了30. 1%,自北至南降低了28. 1%,平均排队长度缩短42.3%,最大排队长度缩短38.1%。证实干道绿波控制方案可有效的节约行程时间,缓解城市道路的交通拥堵状况。     

面向潮汐交通流的信号控制策略优化

为缓解城市潮汐交通道路的拥堵程度,提高道路通行效率,以青岛市黄岛经济技术开发区滨海大道为例,综合考虑道路沿线用地性质以及远景规划方案,结合单点交叉口配时方法以及考虑受车辆排队影响的相位差算法,采用分段绿波控制方式,并通过设置瓶颈控制适当缓解下游交通压力,实现车辆连续快速通过各交叉口.运用Vissim仿真软件进行交通仿真,对所得数据进行数理统计分析,结果表明该方法有效提高了道路的通行效率,缓解了潮汐交通拥堵现象.     

基于环境及排队长度的桥头交叉口信号配时优化

为了提高桥头交叉口的通行能力以及减轻桥梁的承重力,提出了基于机动车比功率(VSP)环境影响因素和排队长度的交叉口信号配时优化方法;建立以减少排放和降低排队长度为总目标的信号交叉口优化模型,使用Matlab进行代码编程求解,达到优化信号配时之目的;并以福清市玉融大桥南侧桥头交叉口实例进行验证。结果表明:在晚高峰阶段,交通总排放量降低11.5%,桥上排队长度降低16.1%。     

基于IE思想的城市交通道路交叉口的规划设计

基于城市主要道路交叉口实际情况的调查,该论文结合了工程理论知识和方法,通过工作抽样和秒表计时的方法,该论文收集了道路交叉口的基本数据跟信息,然后通过排队论中M/D/1的模型来确定车辆的平均等待时间,接着从设备布置跟人员安排的角度来实现道路的全面提高。通过采用AHP(根据某些目标)来实现采用方案的选择跟评价。结果表明,对道路交叉口的既有方案的分析跟优化能有效地降低交通压力,以及在保证交通安全的前提下提高道路通行能力。     

基于交叉口群关联特性的主路径变向车道控制优化

交叉口群的瓶颈路径是发生交通拥堵的主要路段,通过分析交叉口群关联交通特性,及各方向交通流对关键路径变向车道的影响,基于交通波理论,应用图线结合法,建立周期优化模型和相位差约束模型.以青岛西海岸经济新区江山南路交叉口群为研究对象,系统分析交通优化策略和设计方案,运用交通仿真进行效果分析,验证了适应于拥堵严重的交通网络的信号控制优化方法的合理性.     

基于大数据分析的交叉口时空协同优化方法

针对城市交叉口交通拥堵频发的状况,以电子警察卡口、线圈检测器、视频监控采集的路网交通信息数据为基础,基于交通大数据分析,对交叉口的交通运行进行时空协同优化.协同优化时,首先对采集的交叉口交通大数据进行分析挖掘,精准剖析现有交叉口存在的问题,找出交叉口交通流的运行特征,再从时间、空间两个维度根据实际交通状况进行渠化方案设...     

短距交叉口交通问题及渠化、信控优化研究

通过VISSIM仿真分析，针对存在的二次排队、进口道能力不足、服务水平低、开口过大等问题，对交叉口开口宽度优化、渠化设计、全向交叉口信号联控与非联控仿真对比及配时设计，较好解决短距交叉口存在的交通问题。     

道路平面交叉口次路远引几何参数设置及通行效率研究

次要车流的左转和直行对交叉口车辆运行影响较大,特别是主路交通流量较大时尤为明显,通过次要道路车流远引的方式可以减少交叉口车辆冲突,有利于提高交叉口运行效率。分析了平面交叉口次路远引适用条件与车流组织方法,以延误最小为目标,构建了远引回转车流掉头位置、远引车辆掉头排队车道长度、远引掉头处开口长度与宽度等关键几何参数计算模型,提出了次路远引交叉口延误和通行能力等计算方法。结合实例验证了上述方法的可行性,仿真显示,在一定条件下平面交叉口次路远引可有效减少信号相位数和车辆平均延误,表明了平面交叉口次路远引的交通组织方法对优化城市道路交叉口设计有较好的应用价值。     

A GIS-Based Traffic Signal Coordination and Information Management System

Abstract: This paper discusses research conducted at the Georgia Institute of Technology that investigated the use of geographic information system (GIS) technology as a tool in traffic signal information management and signalized intersection coordination. TRANSYT-7F is the most widely used and respected computer model for optimizing the coordination of traffic signals. Unfortunately, creating an optimal TRANSYT-7F model is very costly. The hypothesis of this research was that using a specialized GIS in conjunction with TRANSYT-7F could enhance the process of coordinating a traffic signal system. The research resulted in the development of a GIS-based traffic signal coordination and information system that operates on a microcomputer. This system is an improvement over existing TRANSYT-7F models because relationships between intersections do not have to be encoded manually. Instead, the system takes advantage of the GIS's topologic data structure, which provides these relationships. The process of analyzing different network optimization scenarios is simplified with this system because the user need only to select intersections to be coordinated from the GIS graphic display rather than cutting and pasting from existing input files. Alternatively, the system can serve as a multipurpose signal information system and play a vital role in decision support. It can provide improved access to signal data and allows for swift identification of intersections that experience excessive delays or unacceptable levels of service.     

城市道路交叉口交通特征分析

为了更好地把握我国城市道路交叉口的交通特性,从交叉口交通流通行环境、交通流构成、交通渠化形式以及交通信号控制设计等方面入手进行了研究。为使通行能力、道路设计、交通安全等相关研究能更切合我国的实际情况,分析了现状特征,重点对比交通渠化的各种设计模式。最后指出了在交叉口设计中需要特别注意的几个问题。     

Reconstructing the Traffic State by Fusion of Heterogeneous Data

Abstract: We present an advanced interpolation method for estimating smooth spatiotemporal profiles for local highway traffic variables such as flow, speed and density. The method is based on the “adaptive smoothing method” which takes as input stationary detector data as typically collected by traffic control centers. We generalize this method to allow for fusion with floating car data or other traffic information. The resulting profiles display transitions between free and congested traffic in great detail, as well as fine structures such as stop‐and‐go waves. We establish the accuracy and robustness of the method and demonstrate three potential applications: (1) compensation for gaps in data caused by detector failure; (2) separation of noise from dynamic traffic information; and (3) the fusion of floating car data with stationary detector data.     

基于交叉路口的动态OD反推模型与算法研究

交叉路口各进出口道之间的实时交通量是信号控制系统重要的输入数据 ,也是难以获得的数据。本文回顾了动态OD反推理论的发展历程 ,以交叉路口各进出口道检测到的路段流量时间序列为基础 ,分析了交叉路口实时交通量的特点 ,提出了基于交叉路口的改进参数优化模型 ,设计了遗传算法对问题进行求解 ,并讨论了算法中的六个关键问题。实例研究表明 ,模型和算法具有较高的效率和准确性 ,能够应用于在线系统。     

Harmonization for Omnidirectional Progression in Urban Traffic Control

I describe harmonization as part of my work on distributed, knowledge-based, real-time, traffic-adaptive control of street and highway ramp traffic signals. The control system developed in prior efforts includes a two-stage learning process. The first stage optimizes the control of steady-state traffic at a single intersection and over a network of streets. The second stage of learning, not related yet to harmonization, deals with the predictive/reactive control of dynamic traffic flow in street networks. However, the control regimes at the individual intersections do not consider the time behavior of adjacent intersection control regimes. Optimal traffic flow in street networks must be with reference to signalization, phasing, and harmonization of control at all intersections. Harmonization represents the best approximation to a coordinated omnidirectional progression ("green wave"). This means that the resulting control regime produces a minimum of the sum, over all intersections, of delay times due to red lights and of unused green periods, each contributing term being weighted by the respective traffic flow values. The system has been tested in the laboratory on a range of scenarios (in terms of geometries and traffic flows) and has been found to perform as expected.     

浅谈城市道路平面交叉口的规划设计与管理

针对目前城市中日益突出的交通问题，通过运用道路平面交叉口规划与设计的有关原则和方法，结合实例对平面交叉口进行了统计和分析，指出交叉口存在的问题，并提出解决的初步设想和建议，以期创造良好的交通环境。     

Simulation studies of traffic management strategies for a long tunnel

The Hsueh-Shan Tunnel, the fifth long tunnel in the world, has a total distance of 12.9 km. After the opening of the tunnel, traffic demand between Taipei and I-Lan increased dramatically. However, efficient traffic management strategies for the Hsueh-Shan Tunnel need to be developed and evaluated accordingly in order to alleviate traffic congestion due to high demand and/or possible incidents. The research aims to evaluate possible traffic management strategies based on available control devices through simulation-assignment techniques. Possible traffic management strategies, including access control (ramp metering), lane control and route guidance, are proposed and examined through numerical experiments. In order to analyze traffic management strategies based on simulation, DynaTAIWAN, a simulation-assignment model, is developed to simulate traffic control strategies and reflect driver’s response to route guidance. Several indexes, including vehicle queue length, average density and average speed, are used in the comparisons. The results show that ramp control provides the best benefits compared to other strategies and can reduce the average queue length by about 18%.