影响高速公路交通安全的道路因素分析

针对高速公路交通的特点,从高速公路的设计、建设与使用等方面分析了道路线形及其组合、道路路面、交通环境对道路交通安全的影响。     

高速公路改扩建工程路面施工阶段交通组织研究

为提高我国高速公路改扩建工程路面施工阶段交通组织的有效性,对高速公路改扩建工程特点进行阐述,基于高速公路改扩建工程开展需求对其路面施工阶段交通组织原则进行总结,之后梳理施工期间的交通组织要点、提出相关措施,希望能为相关领域进行更深入的研究提供参考,引发更多关于高速公路改扩建工程路面施工阶段交通组织方案制订的探讨。     

高速公路改扩建施工路段交通组织研究

高速公路建成通车多年之后,其路用性能不断下降,这已是高速公路运营中存在的难题之一。养护高速公路是提升其路用性能的主要手段,在养护阶段如何有效开展交通组织,对交通安全及施工效益有巨大影响。通过分析高速公路改扩建项目施工期内交通组织,对施工安全交通组织体系进行全面介绍,设计出相应的模型,对其合理性进行验证,从而全面提升高速公路改扩建项目交通组织管理能力,保证道路行车安全。     

髙速公路改扩建工程施工交通组织安全评价及关键技术措施

受诸多因素制约,国内高速公路改扩建工程通常施工时不允许中断交通,如何做好施工交通组织,是高速公路改扩建工程成败的关键。结合福泉厦漳高速公路改扩建工程,重点研究高速公路改扩建期间交通组织的安全评价及对策,并提出实现四车道保通的关键技术措施。     

基于VISSIM的高速公路隧道交通事故影响仿真分析

为了研究高速公路长大隧道内交通事故影响程度,文章以江西省第一长隧道九岭山隧道为研究对象,通过VISSIM交通仿真软件建立交通仿真模型,在设置不同等级的交通流量以及大货车交通比例的条件下,仿真获得高速公路长大隧道交通事故发生后车辆排队长度以及延误时间,用以分析高速公路隧道内交通事故对隧道通行能力的影响,以更大程度上实现高速公路隧道安全行车。     

浅谈高速公路改扩建工程交通组织方案

文章结合广西沿海高速公路改扩建一期工程实例,阐述了高速公路改扩建工程施工阶段交通组织的总体方案,并介绍了在路基、路面、桥梁施工阶段的交通组织具体措施,为同类型高速公路改扩建施工提供参考。     

论高速公路监控系统的体系结构

高速公路监控技术为高速公路的信息化建设提供了很好的手段,对高速公路交通监控系统的内涵、功能和体系结构设计等进行了初步探讨。     

交通载荷位置和速度对桥梁的影响

桥梁是高速公路的重要组成部分,随着高速公路通行的重型车辆不断增多,部分桥梁的交通载荷分布情况已发生变化,因此,研究交通载荷位置和车辆速度对桥梁的影响十分必要。鉴于此,对江西省内的高速公路桥梁进行全天24h车流量调查,并以此为基础,研究交通载荷与桥梁响应之间的关系。建立有限元数学模型,利用BDANS软件研究车辆载荷的横向位置、车速对桥梁的影响,为今后高速公路重载桥梁设计提供理论依据。     

铿锵跨越 磅礴前行 开创高速公路管养与服务新篇章——广西交通投资集团南宁高速公路运营有限公司

广西交通投资集团南宁高速公路运营有限公司前身为南宁高速公路管理处,2008年转企改制成为广西交通投资集团旗下的全资子公司,主要负责南宁至都安、南宁至宾阳、南宁至坛洛、南宁环城共313公里高速公路的收费、     

临沂市高速公路绿化建设管理的实践与思考

京沪、日东高速公路临沂段的建成通车,不仅对贯通国道主干线,完善山东高速公路网,构筑大交通格局有着重要意义,同时对促进华北、华东地区经济交往,进一步改善临沂市对外交通条件和投资环境具有特别重要的意义.绿化是高速公路的重要组成部分,是高速公路的点睛之笔,是构建畅、安、舒、美大交通环境舒美部分的重要载体.结合临沂市高速公路建设及运营管理情况,就高速公路绿化建设管理中的有关问题进行初步探讨.     

Noise prediction for highways in Thailand

A model of highway traffic noise is formulated based on vehicle types. The data were collected from local highways in Thailand with free-flow traffic conditions. First, data on vehicle noise was collected from individual vehicles using sound level meters placed at a reference distance. Simultaneously, measurements were made of vehicles’ spot speeds. Secondly, are data for building the highway traffic noise model. This consists of traffic noise levels, traffic volumes by vehicle classification, average spot speeds by vehicle type, and the geometric dimension of highway sections. The free-flow traffic noise model is generated from this database. A reference energy mean emission level (the basic noise) level for each type of vehicles is developed based on direct measurement of Leq (10 s) from the real running condition of each type of vehicles. Modification of terms and parameters are used to make the model fit highway traffic characteristics and different types of vehicle.     

福州市交通安全与智能交通系统探讨

智能交通系统是一个高科技集成系统,它综合运用各种高新技术于整个交通管理系统之中,可以系统、全面、高效地提高交通运输的安全性.文章阐述了智能交通系统在交通安全中的作用及在福州市的应用情况,指出了福州市发展智能交通的方向,以提高福州市的交通安全管理水平.     

Observing freeway ramp merging phenomena in congested traffic

This work conducts a comprehensive investigation of traffic behavior and characteristics during freeway ramp merging under congested traffic conditions. On the Tokyo Metropolitan Expressway, traffic congestion frequently occurs at merging bottleneck sections, especially during heavy traffic demand. The Tokyo Metropolitan Expressway public corporation, generally applies different empirical strategies to increase the flow rate and decrease the accident rate at the merging sections. However, these strategies do not rely either on any behavioral characteristics of the merging traffic or on the geometric design of the merging segments. There have been only a few research publications concerned with traffic behavior and characteristics in these situations. Therefore, a three‐year study is undertaken to investigate traffic behavior and characteristics during the merging process under congested situations. Extensive traffic data capturing a wide range of traffic and geometric information were collected using detectors, videotaping, and surveys at eight interchanges in Tokyo Metropolitan Expressway. Maximum discharged flow rate from the head of the queue at merging sections in conjunction with traffic and geometric characteristics were analyzed. In addition, lane changing maneuver with respect to the freeway and ramp traffic behaviors were examined. It is believed that this study provides a thorough understanding of the freeway ramp merging dynamics. In addition, it forms a comprehensive database for the development and implementation of congestion management techniques at merging sections utilizing Intelligent Transportation System.     

Highway traffic noise effects on land price in an urban area

The study evaluates the monetary effect of traffic noise on property values in Seoul, Korea. Hedonic price models are estimated using the zone-based data that includes traffic noise levels, official land price, land use classification, distance to roadways, type of nearby roadway facilities, and traffic characteristics. It is found that a 1% increase in traffic noise associated with a 1.3% decline in land price. Based on this, the annual cost per kilometer due to traffic noise is about $347 thousand.     

Estimating the costs of political populism: Traffic violation pardons in Korea

Since 1995, four presidents have granted six traffic violation pardons in Korea, and 24.6 million individuals have been the beneficiaries of these pardons. The objective of this paper is to explore how costly traffic violation pardons are by finding out the effects of traffic violation pardons on traffic accidents, and then estimating the economic costs caused by traffic violation pardons. Traffic violation pardons have the effect of raising traffic accidents by 4.3% and 3.6% per year and the economic costs of traffic accidents by 4.2% and 3.5% per year for two consecutive years after the pardons are granted.     

Recent developments in traffic flow modeling using macroscopic fundamental diagram

ABSTRACT

This paper presents an overview of the recent developments in traffic flow modelling and analysis using macroscopic fundamental diagram (MFD) as well as their applications. In recent literature, various aggregated traffic models have been proposed and studied to analyse traffic flow while enhancing network efficiency. Many of these studies have focused on models based on MFD that describes the relationship between aggregated flow and aggregated density of transport networks. The analysis of MFD has been carried out based on experimental data collected from sensors and GPS, as well as simulation models. Several factors are found to influence the existence and shape of MFD, including traffic demand, network and signal settings, and route choices. As MFD can well express the traffic dynamics of large urban transport networks, it has been extensively applied to traffic studies, including the development of network-wide control strategies, network partitioning, performance evaluation, and road pricing. This work also presents future extensions and research directions for MFD-based traffic modelling and applications.     

Adaptive traffic signal control with actor-critic methods in a real-world traffic network with different traffic disruption events

The transportation demand is rapidly growing in metropolises, resulting in chronic traffic congestions in dense downtown areas. Adaptive traffic signal control as the principle part of intelligent transportation systems has a primary role to effectively reduce traffic congestion by making a real-time adaptation in response to the changing traffic network dynamics. Reinforcement learning (RL) is an effective approach in machine learning that has been applied for designing adaptive traffic signal controllers. One of the most efficient and robust type of RL algorithms are continuous state actor-critic algorithms that have the advantage of fast learning and the ability to generalize to new and unseen traffic conditions. These algorithms are utilized in this paper to design adaptive traffic signal controllers called actor-critic adaptive traffic signal controllers (A-CATs controllers).The contribution of the present work rests on the integration of three threads: (a) showing performance comparisons of both discrete and continuous A-CATs controllers in a traffic network with recurring congestion (24-h traffic demand) in the upper downtown core of Tehran city, (b) analyzing the effects of different traffic disruptions including opportunistic pedestrians crossing, parking lane, non-recurring congestion, and different levels of sensor noise on the performance of A-CATS controllers, and (c) comparing the performance of different function approximators (tile coding and radial basis function) on the learning of A-CATs controllers. To this end, first an agent-based traffic simulation of the study area is carried out. Then six different scenarios are conducted to find the best A-CATs controller that is robust enough against different traffic disruptions. We observe that the A-CATs controller based on radial basis function networks (RBF (5)) outperforms others. This controller is benchmarked against controllers of discrete state Q-learning, Bayesian Q-learning, fixed time and actuated controllers; and the results reveal that it consistently outperforms them.     

地铁站点施工期交通组织工作思路与方法

由于地铁站点施工对城市交通会产生极大的影响,因此提前做好施工期间系统的交通组织工作,对保障城市正常生产、生活和地铁站点的顺利施工有着重要意义。文章结合成都地铁二号线站点施工期间交通组织工作经验,针对地铁施工的特点,就施工期间的交通组织工作思路、方法等进行探讨。     

Congestion avoidance in city traffic

The number of vehicles on the road (worldwide) is constantly increasing, causing traffic jams and congestion especially in city traffic. Anticipatory vehicle routing techniques have thus far been applied to fairly small networked traffic scenarios and uniform traffic. We note here a number of limitations of these techniques and present a routing strategy on the assumption of a city map that has a large number of nodes and connectivity and where the vehicles possess highly varying speed capabilities. A scenario of operation with such characteristics has not previously been sufficiently studied in the literature. Frequent short‐term planning is preferred as compared with infrequent planning of the complete map. Experimental results show an efficiency boost when single‐lane overtaking is allowed, traffic signals are accounted for and every vehicle prefers to avoid high traffic density on a road by taking an alternative route. Comparisons with optimistic routing, pessimistic routing and time message channel routing are given. Copyright © 2014 John Wiley & Sons, Ltd.     

Determinants of air cargo traffic in California

Studies on the economic impacts of air cargo traffic have been gaining traction in recent years. The slowed growth of air cargo traffic at California’s airports, however, has raised pressing questions about the determinants of air cargo traffic. Specifically, it would be useful to know how California’s air cargo traffic is affected by urban economic characteristics. Accordingly, this study estimates the socioeconomic determinants of air cargo traffic across cities in California. We construct a 7-year panel (2003–2009) using quarterly employment, wage, population, and traffic data for metro areas in the state. Our results reveal that the concentrations of both service and manufacturing employment impact the volume of outbound air cargo. Total air cargo traffic is found to grow faster than population, while the corresponding domestic traffic grows less than proportionally to city size. Wages play a significant role in determining both total and domestic air cargo movement. We provide point estimates for traffic diversion between cities, showing that 80% of air cargo traffic is diverted away from a small city located within 100 miles of a large one. Using socioeconomic and demographic forecasts prepared for California’s Department of Transportation, we also forecast metro-level total and domestic air cargo tonnage for the years 2010–2040. Our forecasts for this period indicate that California’s total (domestic) air cargo traffic will increase at an average rate of 5.9% (4.4%) per year.