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The traffic during rush hour in metropolises is always in heavy congestion, so the wagon trucks of logistic transportation are mostly forbidden during rush hour. In fact, quite a few logistic transportations are fulfilled by converted passenger vehicles. This paper aims to model the logistic companies' behaviors and see through the effect of their cooperation modes on the companies and on the whole traffic conditions. The logistic companies decide their transportation pricing, warehouse using and route choosing separately or as a group (cooperation) to compete with others. It is also assumed that the heavy freight vehicles, light freight vehicles and the auto vehicles share the same network. Three models based on variational inequalities are proposed to describe the companies' behaviors when there is no cooperation, simple cooperation and deep cooperation, respectively, and the modified diagonalization method is used to solve these models. The total transportation demand is elastic, which depends on the users' choice of logistics company and further depends on all the companies' prices, warehouse and route choices. The goodness of different coalitions to the companies and the whole traffic system is well investigated in the numerical examples. [ABSTRACT FROM AUTHOR]

With the rapid development of transportation, traffic questions have become the major issue for social, economic and environmental aspects. Especially, during serious emergencies, it is very important to alleviate road traffic congestion and improve the efficiency of evacuation to reduce casualties, and addressing these problems has been a major task for the agencies responsible in recent decades. Advanced road guidance strategies have been developed for homogeneous traffic flows, or to reduce traffic congestion and enhance the road capacity in a symmetric two-route scenario. However, feedback strategies have rarely been considered for pedestrian-vehicle mixed traffic flows with variable velocities and sizes in an asymmetric multi-route traffic system, which is a common phenomenon in many developing countries. In this study, we propose a weighted road occupancy feedback strategy (WROFS) for pedestrian-vehicle mixed traffic flows, which considers the system equilibrium to ease traffic congestion. In order to more realistic simulating the behavior of mixed traffic objects, the paper adopted a refined and dynamic cellular automaton model (RDPV_CA model) as the update mechanism for pedestrian-vehicle mixed traffic flow. Moreover, a bounded rational threshold control was introduced into the feedback strategy to avoid some negative effect of delayed information and reduce. Based on comparisons with the two previously proposed strategies, the simulation results obtained in a pedestrian-vehicle traffic flow scenario demonstrated that the proposed strategy with a bounded rational threshold was more effective and system equilibrium, system stability were reached. [ABSTRACT FROM AUTHOR]

In this paper, a new car-following model is proposed by considering driver's desired velocity according to Transportation Cyber Physical Systems. The effect of driver's desired velocity on traffic flow has been investigated through linear stability theory and nonlinear reductive perturbation method. The linear stability condition shows that driver's desired velocity effect can enlarge the stable region of traffic flow. From nonlinear analysis, the Burgers equation and mKdV equation are derived to describe the evolution properties of traffic density waves in the stable and unstable regions respectively. Numerical simulation is carried out to verify the analytical results, which reveals that traffic congestion can be suppressed efficiently by taking driver's desired velocity effect into account. [ABSTRACT FROM AUTHOR]

With more attentions drawn to transportation, we find that it is available to analyze transportation system by using weighted networks. Distinguishing from traditional method, we introduce a dynamic weighted network model with evolutional size and weight. Additionally, the expected strength allocation vector of the model consists of a deterministic component reflecting preferential attachment and a random component, which can characterize the realistic network better. In this paper, we obtain the degree and strength distributions of the weighted network and we conclude that the network has scale-free characteristics. [ABSTRACT FROM AUTHOR]

We study the emergence of self-organized traffic flow conventions in a multiagent system. A transport system is modeled as a discrete grid, on which agents governed by a neural network can move with a velocity that depends on the quantity and directions of the agents occupying the site of the grid. We show that evolution leads to traffic flow conventions that depend on the transport system geometry. We also show that if we split the agents into different "species" that move simultaneously on the transport system but that cannot exchange genetic information, their mutual influence leads to the same traffic flow convention for all the species. Finally, we develop a very simple evolutionary dynamic model (solvable both numerically and analytically) that gives an interpretation of our results. [ABSTRACT FROM AUTHOR]

Modern urban traffic management depends heavily on the efficiency of road features, such as controlled intersections and multi-lane roundabouts. Vehicle throughput at any such configuration is modified by traffic mix, by rules governing manoeuvrability and by driver observance, as well as by traffic density. Here, we study heterogeneous traffic flow on two-lane roads through a cellular automata model for a binary mix of long and short vehicles. Throughput is investigated for a range of arrival rates and for fixed turning rate at an intersection: manoeuvres, while described in terms of left-lane driving, are completely generalisable. For a given heterogeneous distribution of vehicle type, there is a significant impact on queue length, delay times experienced and throughput at a fixed-cycle traffic light controlled two-way intersection and two-lane roundabout, when compared to the homogeneous case. As the proportion of long vehicles increases, average throughput for both configurations declines for increasing arrival rate, with average queue length and waiting time correspondingly increased. The effect is less-marked for the two-lane roundabout, due to absence of cross-traffic delays. Nevertheless, average waiting times and queue lengths remain uniformly high for arrival rates >0.25 vehicle per second (900 vph) on entry roads and for long vehicle proportion above 0.30–0.35. [ABSTRACT FROM AUTHOR]

In real traffic, the traffic system is usually composed of different types of vehicles, which have different parameters. How these parameters, especially the lengths of the vehicles, influence the traffic behaviors and transportation capability has seldom been investigated. In this paper, we study the mixed traffic system using the cellular automata traffic flow model. The simulation results show that when the road occupancy rate is large, increasing the fraction of long vehicles can apparently, improve the transportation capability. The influence of slow vehicles fraction on the average velocity of vehicles has been discussed, and it is found that the influences are very different when the difference of vehicle length is considered or not. [ABSTRACT FROM AUTHOR]

The NaSch model is a probabilistic cellular automaton (CA) model for the description of single-lane highway traffic. Based on this model, we propose a new cellular automata model for the railway traffic. The signaling system adopted in this work is the moving block signaling system. In our model, the distance between the following train and its leading train takes into account the velocity of the leading train. The simulation results demonstrate that our model is suitable for simulating the railway traffic. Compared our scheme to the traditional moving-space-block scheme, it is obvious that using our scheme, not only the line capacity can be increased, but also the traffic flow states are safer. [ABSTRACT FROM AUTHOR]

In this paper, we propose a new technique to control the vehicle states in two-lane traffic. A type of the control signals has been designated at a given site (i.e., signal point) of the road. Under the effect of control signal, the drivers on the right lane will slow down when their vehicles pass the signal point. We test this technique for the two-lane traffic model that is based on the deterministic NaSch traffic model. The simulation results indicate that the traffic flow states can be changed from disorder to order by the control signal, and these ordered states are safer. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the lane expansion effect of the tollbooth system. To this end, two typical values of randomization probability p:p=0.5 and p=0.1 are chosen. It is shown that for p=0.5, the full capacity of the single lane highway can be restored. However, for p=0.1, our simulations show that the full capacity of the single lane highway cannot be restored due to the existence of the merge section in the lane expansion section. Moreover, we have investigated the dependence of road capacity on the length of lane expansion section as well as the effects of the positions of the tollbooths in the lane expansion section under different values of p. [ABSTRACT FROM AUTHOR]