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With the increase in travel demand and car ownership, traffic congestion is becoming more and more serious. To alleviate traffic congestion, based on the user heterogeneity, this paper proposes to implement both toll and tradable credit scheme for the public-private partnership transportation network, i.e., tolling and charging tradable credits for the users who use the government-built public roads and BOT private roads, respectively. Based on the travelers' routing behavior under this mixed strategy, we build the variational inequality model of user equilibrium and market equilibrium. Then, according to the system optimal model, the mixed strategy set can be obtained that promotes the user equilibrium flow pattern to the system optimal flow pattern, and the upper bound of system efficiency loss under mixed strategy is also derived. Furthermore, we propose two bi-level programming models covering other objectives and obtain the optimal mixed strategy. Finally, a numerical experiment on a specific road network is conducted, which can obtain the specific amount of tradable credits and charging value for each public road and BOT private road respectively, and the total number of windows for that need to be set in the road network. [ABSTRACT FROM AUTHOR]

In order to ease the congestion of macro traffic network and reduce the fuel consumption of vehicles, the equilibrium equations of the traffic flow in the congested area are established based on subregions classified by macroscopic fundamental diagram (MFD) according to different network state. Then the road network is divided into two categories, such as intersection and road section and a network energy consumption estimation model is established according to the parameter of MFD. Dual objective optimal control model of the congestion area boundary is built up with the goal of lowest energy consumption and the highest travel completion rate of vehicles in macro network. Finally, the actual city road network is used as the test object. By comparing the control scheme of the no boundary control, Bang-Bang entrance boundary control and dual objective optimal control scheme, the following conclusions are got: 1) At the peak time, the network evacuation capability under the dual objective optimal control is improved by 20.14% and 2.1% compared With the no boundary control and Bang-Bang entrance boundary control at the same time, vehicle fuel consumption decreased by 43.14% and 24.48% respectively. 2) Dual objective optimal control method can effectively improve the traffic density equilibrium inside and outside the congested area. 3) The boundary control of the congested area in macro network can effectively reduce the congestion level during rush hour and improve the evacuation ability of the whole network. [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]

The port trucks congestion problem existed in many ports. For this reason, the port trucks route cost optimization model faced the 'work surface' was established by exploring the effect factors of port trucks operation efficiency and the cost composition of the truck route in the container gantry crane system. Then genetic algorithm-ant colony optimization algorithm (GA-ACO) is proposed in view of the model and analyzed the problems with an example, compared optimization results with those by ant colony algorithm from the changes of truck route convergence, variable cost, penalty cost and total cost. The results show that genetic algorithm-ant colony optimization algorithm is faster converge to the optimal solution and gain less cost. [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]

Traffic incident happens frequently in urban traffic network, which affect normal operation of traffic system seriously, so that study on congestion control strategies under traffic incident is very important. The design of temporary vehicle movement bans and location of variable message sign under traffic incident was addressed. A bidevel programming model was proposed to formulate this problem. The upper level problem was to minimize the total travel cost in the view of traffic management agencies, and the lower level problem was to present travelers' dynamic route choice behavior under temporary vehicle movement bans and variable message sign using the simulation of cell transmission model, then a genetic algorithm was proposed to solve this bi-level optimization model. Computational results show that the temporary vehicle movement bans methods and variable message sign can alleviate the network congestion caused by traffic incident effectively and improve system performance of traffic network. [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]