Traffic wave

About: Traffic wave is a research topic. Over the lifetime, 2106 publications have been published within this topic receiving 62117 citations. The topic is also known as: phantom traffic jam & ghost jams.

Lane Changing Rules Based on Cellular Automaton Traffic Flow Model

Abstract: Lane changing rules in freeway traffic were simulated by using cellular automaton model under condition of periodical boundary. The mean speed and flow volume under different lane changing rules were simulated, the difference of drivers£§ character was taken into account by introducing the flexible lane-changing rules and the influence of lane changing rules on traffic flow was discussed. In the process of computational simulation, the fundamental diagrams of traffic flow under different lane changing rules were obtained by changing traffic flow density. Result shows that models with new lane changing rules will enlarge traffic flow and suppress traffic jam; the best lane changing rule was obtained based on the analysis of point of view for safety.

Traffic breakdowns and freeway capacity as extreme value statistics

Abstract: An analysis of traffic volume time series for dense traffic shows traffic breakdowns, which can be sorted by the frequency of breakdowns dependent on the traffic volume at the beginning of the breakdown. From this empirical breakdown a probability can be extrapolated and breakdowns can be described as extreme events. Three different traffic situations can be distinguished: (a) stable traffic flow where any fluctuations decay over time, (b) metastable traffic flow where fluctuations neither decay nor grow, and (c) unstable traffic flow where a breakdown can be expected with certainty, if a reasonable observation time is provided. The results open new insights in probabilistic description and prognosis of the traffic break-downs. They lead directly to the probabilistic definition of the capacity as a traffic volume leading to an unstable traffic pattern with a given probability within a given observation time. This definition can substitute the existing definitions for the capacity of a freeway and opens the possibility to quantitatively describing the influence of traffic control systems on the traffic flow.

Traffic models for use in vessel traffic systems

Abstract: Traffic management systems for ships are playing an increasingly important role in major ports throughout the world. The function and performance characteristics of these systems are influenced by the physical geometry of the ports and by the dynamics of the port traffic. In a given traffic system intersections between ship routes lead to a potential need for operator intervention to resolve conflicts and promote an orderly and safe flow of traffic. The results in this paper are related to the problem of determining the relative difficulty associated with managing high-density route intersections and for suggesting route structures or regulatory improvements when such flexibility is allowed. The model can be used to distinguish between traffic situations due to high traffic densities and those due to the occurrence of a statistically unusual event. A model is developed for conflicts between ships at route intersections. Quantitative measures are presented for conflict intensity and duration and for intersection capacity. These measures are shown to be related to the geometry of the intersection and to the statistics of the incident flows. An optimum intersection angle is found.

Traffic flow impacts of a congestion assistant

Abstract: This paper presents the results from a microscopic traffic simulation study that was conducted to investigate the impacts of a so-called Congestion Assistant on traffic efficiency and traffic safety. The Congestion Assistant is an in-vehicle system that supports the driver with an Active pedal when approaching a traffic jam and a Stop & Go when driving in a traffic jam. Six variants of the Congestion Assistant with different equipment rates on a four-lane highway with a lane drop were assessed. The traffic simulation tool was calibrated and validated using measured loop data on a segment of the Dutch A12 highway. The Congestion Assistant was found to reduce the amount of congestion significantly, especially due to the Stop & Go. This function led to more efficient car-following behavior by adapting smaller headways and eliminating the reaction time of drivers. The Active pedal of the Congestion Assistant hardly influenced traffic efficiency; rather it affected traffic safety through a safer approach to a jam.

An Intelligent Traffic Monitoring System

Abstract: Traffic is increasing day by day because of the increasing in vehicle usage especially in urban areas. Congestion in traffic also increases with the increase of vehicle numbers. To regulate the flow of vehicles we are presently using traffic light controllers which have three signals. With the help of these signals we can regulate the vehicle's direction. Most of the controllers have some fixed duration for each of the three signals which may leads to the additional congestion in traffic. This congestion we can be avoided by two ways. One is to design an intelligent traffic light controller which alters the duration between each signal. Other is to make the user of the vehicle be aware of the traffic density of the path in which he is travelling. The scope of this paper is to design a system which makes the user to be aware of the traffic with the help of Global Positioning System (GPS) and GSM mobile phones, so that the user can make alternate route if possible or may plan his activity according to the traffic density. The performance of the Intelligent Traffic Light Controller is compared with the Fixed Mode Traffic Light Controller and it is observed that the proposed Intelligent Traffic Light Controller is more efficient than the conventional controller in respect of less waiting time and improvement in the distance travelled by vehicles and efficient operation during emergency mode.