Traffic and Related Self-Driven Many-Particle Systems

Since the subject of traffic dynamics has captured the interest of physicists, many astonishing effects have been revealed and explained. Some of the questions now understood are the following: Why are vehicles sometimes stopped by so-called ``phantom traffic jams'', although they all like to drive fast? What are the mechanisms behind stop-and-go traffic? Why are there several different kinds of congestion, and how are they related? Why do most traffic jams occur considerably before the road capacity is reached? Can a temporary reduction of the traffic volume cause a lasting traffic jam? Under which conditions can speed limits speed up traffic? Why do pedestrians moving in opposite directions normally organize in lanes, while similar systems are ``freezing by heating''? Why do self-organizing systems tend to reach an optimal state? Why do panicking pedestrians produce dangerous deadlocks? All these questions have been answered by applying and extending methods from statistical physics and non-linear dynamics to self-driven many-particle systems. This review article on traffic introduces (i) empirically data, facts, and observations, (ii) the main approaches to pedestrian, highway, and city traffic, (iii) microscopic (particle-based), mesoscopic (gas-kinetic), and macroscopic (fluid-dynamic) models. Attention is also paid to the formulation of a micro-macro link, to aspects of universality, and to other unifying concepts like a general modelling framework for self-driven many-particle systems, including spin systems. Subjects such as the optimization of traffic flows and relations to biological or socio-economic systems such as bacterial colonies, flocks of birds, panics, and stock market dynamics are discussed as well.Comment: A shortened version of this article will appear in Reviews of Modern Physics, an extended one as a book. The 63 figures were omitted because of storage capacity. For related work see http://www.helbing.org

Intelligent Transportation System (ITS) Activities and Needs in IDOT District Offices

While most of the ITS activities are a part of Gary-Chicago-Milwaukee (GCM) Corridor project, there are many other ITS projects throughout Illinois. This study summarizes the needs, current and planned ITS activities in IDOT District Offices. Interviews were conducted with key District personnel involved with ITS. The districts are looking to ITS as a tool to get more done and improve their services to the public, however, they are making decisions based on limited information they can get. The districts are very concerned that new ITS projects are being handed down with only construction funds. This poses a concern because ITS installations will need maintenance, but those funds are not provided, and will have to trade off with existing maintenance needs. The districts are very concerned with their workloads. ITS is becoming an additional responsibility for existing employees who were already overworked. Districts are implementing various levels of ITS on their own initiative, and there are many projects that each district would like to use ITS as a part of. The districts are learning about ITS applications from vendors who are trying to sell products. Several recommendations are made to deal with these issuesThe Illinois Department of Transportationpublished or submitted for publicationnot peer reviewe

ROUNDABOUT WARRANTS: PROPOSED FRAMEWORK FOR FUTURE DEVELOPMENT

The available research in the area of roundabout intersections was surveyed with focus primarily on concerns about their installation. The Federal Highway Administration\u27s 2000 publication, Roundabouts: An Informational Guide, examines what should be done after the decision has been made to install a roundabout. This guide, while a good reference, does not provide specific decision-making criteria, the main focus of this proposed framework. The areas of focus are not to be considered exhaustive or complete but as suggested criteria, as the use of warrants seeks to imply. The areas covered in depth by these criteria are pedestrian volume, horizontal alignment, vertical alignment, and unbalanced flow volumes. In addition, safety and relevant local concerns should be focused on in the overall decision-making process

Light-Emitting Diode (LED) Traffic Signal and Uninterruptible Power Supply (UPS) Usage: A Nationwide Survey

A national survey was conducted to gather information regarding the use of light-emitting diode (LED) traffic lights and uninterruptible power supply (UPS) systems in traffic signal controller cabinets. A survey was mailed out to the individual districts within Illinois DOT, all 49 other state DOTs, and to 79 of the largest cities in the US to find out the degree of utilization and satisfaction about LED traffic signals and UPS systems. At the State DOT level, there was a significant usage of LED lights in traffic signals. The most commonly used brands were Gelcore and Dialight. These accounted for approximately 95% of all LEDs in use at the state level. These results are also echoed in that both Dialight and Gelcore scored over 3.5 (out of 4.0) on the opinion-based degree of satisfaction ratings. At the city level, Dialight and Gelcore were also the most popular brands, and accounted for 91% of all LEDs in use. Dialight scored a near perfect rating of 3.923 and Gelcore also did very well with a satisfaction rating of 3.333. Finally, at the IDOT district level, Dialight was the most commonly used LED (accounting for about 95% of all LEDs in use), and also scored the highest satisfaction rating, at 3.833. The UPS Usage indicates that at the State DOT level, there was some usage of UPS systems, but it had not achieved widespread acceptance. From the 7 states that indicated using UPS systems, 7 different brands of UPS systems were identified. At the city level, there was even less acceptance of UPS systems at the time of this survey, with only 4 cities reported using 6 different brands. All 6 of these brands were in use by only a single city, so no average ratings were available.The Illinois Department of Transportationpublished or submitted for publicationnot peer reviewe