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Focusing on the problem with traffic congestion under changing environmental conditions, this paper proposed a trajectory reward light (TR-light) model by combining reinforcement learning, neural network, multi-agent and traffic simulation technology to optimize the traffic at multi-intersections. This method had considerable merits in the following aspects. The traffic organization plan was formulated based on traffic lights; multi-agent reinforcement learning was used on traffic light control; regional traffic organization was optimized through the coordination of traffic lights; the agent implemented trajectory reconstruction after the execution of each behavior so as to change the vehicle travel path without changing the OD pair, and to calculate the final reward of the agent according to the plan and reconstructed trajectory. Finally, it conducted a traffic simulation experiment through SUMO. The comparison of traffic indicators verifies that the proposed model improves the smoothness of the road network and the traffic state at the multi-intersections. Experiments show that the model is feasible and effectively mitigates the traffic congestion. [ABSTRACT FROM AUTHOR]

For intersection traffic congestion phenomenon, combined fog computing and reinforcement learning theory, this paper proposed a traffic light control model FRTL. The model performed intelligent coordinated control of traffic lights based on real-time traffic flow information. The fog node uploaded the collected real-time traffic flow information to the fog server, and the fog server realized information sharing on the fog platform, and the fog platform combined the processed shared data and Q learning to formulate a traffic light control algorithm. The algorithm used the detected real-time traffic data to calculate a suitable traffic light timing scheme, which was finally applied to the traffic light. The simulation results show that compared with the traditional time-phase control method and the main road control method (ATL), the FRTL control method improves the throughput of intersections, reduces the average waiting time of vehicles, and achieves the goal of properly regulating traffic lights and alleviating traffic congestion. [ABSTRACT FROM AUTHOR]

Road traffic congestion pressure becomes more serious as the number of vehicles increases. Accurate traffic situation detection methods are needed to help in alleviating them. This paper proposed a TraSD-VANET method to detect the traffic situation. In this method, vehicles constituted clusters autonomously and then sent their speed and locations to cluster heads. After receiving data from cluster members, the cluster head calculated the lane weighted average speed and the traffic density adaptively. Afterwards, it estimated the traffic situation in its cluster according to the above calculation results by using fuzzy theory. The simulation results show that the average precision of estimation is improved 16% compared with the CoTEC in four traffic scenarios. This method has important practical value in traffic congestion detection on road. [ABSTRACT FROM AUTHOR]

In recent years, contradiction between supply and demand of urban transport of China is increasingly prominent, and urban traffic jam is getting more and more grave, seriously impact urban residents' normal travel, cause environmental pollution, as well as seriously impact normal operation of urban logistics and become development constraints of the whole city economy. This paper starts with phenomenon of urban traffic jam, and analyzes the present situation, the reasons, the effect and the root of urban traffic jam, and summaries the existing measures for the governance of urban traffic jam from the perspective of urban residents travel and urban logistics. On the basis of summarizing the plugging measures as well as considering the actual situation of our country, this paper establishes the system dynamics model of the management of urban traffic jam with the method of system dynamics. In the last place, this paper takes Beijing as an example, simulates the effect of the typical plugging measures in Beijing, and reaches the suggestions for China to solve urban traffic jam. [ABSTRACT FROM AUTHOR]

Large-scale sports are often held in large cities with heavy traffic, which makes it difficult to satisfy the transportation requirement. To solve this problem, lane reservation method is often adopted. However, it may make the host city's own transportation even worse. Therefore, it is necessary to study how to make lane reservation. While previous studies mainly focus on minimizing the effect on regular transportation, the present study also discusses the possibility of reducing the number of transporting vehicles. By evaluating in advance, some transport tasks can be merged. Accordingly, the number of transport vehicles is cut down and operation cost is reduced. Based on this, a linear integer programming model is formulated. The model is different from the existing models with transportation network, constraint of task path, constraint and measure of making reservation lane. It is shown that the problem is NP-hard. It can be solved by exact methods if it is not too large. The model is proved to be valid and practical by the results shown by Lingo, a Mathematical programming software as in the example of Guangzhou Asia Games. [ABSTRACT FROM AUTHOR]

In order to explore impact of the area-road congestion charging about the residents' residential location and transportation modes, the satisfaction assessment model was proposed to assess the residential location, and the household consumption remaining model was established by the satisfaction, household income and house prices. Area-road congestion charging regimes were implemented, and the generalized commuting traffic impedance and generalized holiday entertainment traffic impedance were got by different trip purpose travel chain characteristics and the corresponding travel mode of family members. The residence of the largest family remaining was got by the household consumption remaining model. The results indicate that area-road congestion charging regimes don't affect low-income mobile home residential choice. A lower level congestion charging does not affect high-income mobile home residential choice, and a higher levels congestion charging makes high-income families mobile home residential from the suburbs to charging regional-border, and it has no affect when the charging level is high. On weekdays and holidays, there is an optimum point both the regional congestion charging level, and the holidays charging optimum point is higher, so it is conducive to maximize for economic efficiency and social utility when the best charging point is implemented. [ABSTRACT FROM AUTHOR]

For the two traffic management strategies of information providing and congestion pricing, this paper studied a union pricing strategy. Firstly, it constructed the decision space of the government and the traffic information supplier, calculated the information market penetration. Then, based on the assumption of elastic demand, it presented an equilibrium model which included two travelers (with/without information), and got the travelers' decision space. It also presented a union pricing model based on the game theory at the same time. Last, it used a testing network to analyze the model. The results show that the level of social benefits influence the information and the congestion pricing more significantly. It also find some results of the model which are in accordance with the practical experience. All of these show the reasonable of the model. [ABSTRACT FROM AUTHOR]

This paper presents a vehicle routing problem in dynamic urban traffic network with real-time traffic information. Both re-current and non-recurrent congestion are considered in the problem. We develop a method to solve the problem by combining the initial routes arrangement with the real-time route adjustment. The initial route planning is made by solving a time-dependent vehicle routing problem under re-current congestion conditions. The genetic algorithm is applied. During the plan implementation, a new mechanism updating at the critical node is proposed to adjust the routes with real-time traffic information subject to the unexpected traffic accidents in non-recurrent congestion environment. Through the numerical simulation, the results show that the new route updating mechanism is more effective than others in the literatures, and the advantage by adopting the new mechanism becomes more prominent when the network becomes more dynamic. [ABSTRACT FROM AUTHOR]

In view of the differences between the vehicles, the multi-type stochastic transportation network equilibrium problem was considered. Firstly, we assumed that the traffic manager was environmentally friendly, who tried to reduce the total emission by charging congestion and emission tolls according to the type of vehicle. Therefore, the optimal toll was deduced based on the classical models for user equilibrium and system optimal. Secondly, we proposed three policy evaluation indicators based on efficiency loss. Finally, a numerical example was given. [ABSTRACT FROM AUTHOR]