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.

Effects of the number of on-ramps on the ring traffic flow

Abstract: Since ramps are an important composition of traffic systems and there often exist multi ramps in a traffic system, the number of ramps can have great effects on main road traffic and produce some complex phenomena. In this paper, we employ the model presented by Tang et al. [2009 Communications in Theoretical Physics 51(1) 71] to further study the effects of the number of on-ramps on the stability of traffic flow on a ring road. The numerical results show that this model can reproduce some complex traffic phenomena resulting from multi on-ramps on the ring road and the effects of the number of on-ramps on traffic flow, but the phenomena and the effects are both related to the initial density of the main road.

Some Operational Features in Bicycle Traffic Flow: Observational Study

Abstract: This study investigated the operational features in bicycle traffic flow on bicycle-only paths. A field investigation was conducted on four bicycle-only paths in the vicinity of bottlenecks in the city of Nanjing, China; two were one-lane paths and two were two-lane paths. The cumulative curve method was used to extract from videos traffic flow information, such as bicycle speeds, flow, and density. The fundamental diagram with free-flow and congested traffic state was constructed with the use of actual traffic data. Data analysis showed that the capacity of bicycle traffic flow on the one-lane and two-lane paths was 3,960 bicycles per hour and 8,100 bicycles per hour, respectively. The critical density was approximately 100 bicycles per kilometer per lane. Average bicycle speed and speed variation decreased as bicycle density increased. The probability of overtaking was highest when bicycle traffic was slightly congested. The observational study showed that even when average speed was quite low, bicycle ...

Microscopic dynamic traffic management: Simulation of two typical situations

Abstract: This paper presents an evaluation of two typical situations of Microscopic Dynamic Traffic Management. Where Dynamic Traffic Management aims to more efficiently use existing road capacity by generic measures, Microscopic Dynamic Traffic Management anticipates suboptimal use of the available infrastructure by disturbing behavior of one or a few drivers. Using simulation, anticipation of slow predecessors in the same lane and anticipation of slow merging vehicles from an on-ramp are assessed on throughput, average travel time loss and traffic flow stability. The simulation results show positive effects, mainly on traffic flow stability, but also on throughput and travel time in the case of anticipating slow merging vehicles.

Study of the effect of traffic volume and road width on pcu value of vehicles using microscopic simulation

Abstract: The knowledge of traffic volume is an important basic input required for planning, analysis and operation of roadway systems. Expressing traffic volume as number of vehicles passing a given section of road or traffic lane per unit time will be inappropriate when several types of vehicles with widely varying static and dynamic characteristics are comprised in the traffic. The problem of measuring volume of such heterogeneous traffic has been addressed by converting the different types of vehicles into equivalent passenger cars and expressing the volume in terms of Passenger Car Unit (PCU) per hour. The vehicles of highly heterogeneous traffic with widely varying physical and operational characteristics such as the one prevailing on Indian roads, occupy based on the availability of space, any convenient lateral position on the road without any lane discipline. The interaction between moving vehicles under such heterogeneous traffic condition is highly com- plex. The results of the study, provides an insight into the complexity of the vehicular interaction in heterogeneous traffic. The PCU estimates, made through microscopic simulation, for the different types of vehicles of heterogeneous traffic, for a wide range of traffic volume and roadway conditions indicate that the PCU value of a vehicle significantly changes with change in traffic volume and width of roadway.

Optimization of congested traffic by controlling stop-and-go waves.

Abstract: We propose a new optimization strategy based on inducing stop-and-go waves on the main road and controlling their wavelength. Using numerical simulations of a recent stochastic car-following model we show that this strategy yields optimization of traffic flow when implemented in systems with a localized periodic inhomogeneity, such as signalized intersections and entry ramps. The optimization process is explained by our finding of a generalized fundamental diagram (GFD) for traffic, namely a flux-density-wavelength relation. Projecting the GFD on the density-flux plane yields a two-dimensional region of stable states, qualitatively similar to that found empirically [Kerner, Phys. Rev. Lett. 81, 3797 (1998)] in synchronized traffic.