2017 International Conference on Service Systems and Service Management, 2017
This Congestion tolls provide an efficient way to mitigate traffic congestion. In deterministic n... more This Congestion tolls provide an efficient way to mitigate traffic congestion. In deterministic networks, an optimal routing of traffic can arise as a user equilibrium by levying marginal-cost toll. In reality, traffic demands vary day in day out. The uncertainty of demand brings difficulties to design transport policies in theory and to implement the traffic coordination in practice. The expected travel budget is defined by involving the mean marginal-cost toll into the expected travel time, and a equilibrium model is established. We compare the expected social cost of the equilibrium and the system optimum to find the efficiency loss of the marginal-cost toll. It is found that the network performance degrades as demand variation goes up. Thus the control of demand variation could be an effective assistant tool to improve the efficiency of congestion pricing policies.
Transportation Research Part E: Logistics and Transportation Review, 2021
Abstract This paper examines the morning commuting flow patterns in a many-to-one public transit ... more Abstract This paper examines the morning commuting flow patterns in a many-to-one public transit line. Multi-class commuters with different degrees of sensitivity towards crowding are considered. At user equilibrium, trains arriving at the destination at approximately the work start time are found to be either more or less congested at the intermediate stations, depending on the spatial distribution of commuter class at each station. In addition, the system optimal crowding fare is found to be train-dependent and may fluctuate over time at each station. Finally, the theoretical properties of morning commuting flow patterns and crowding fare are illustrated through numerical examples.
2009 International Conference on New Trends in Information and Service Science, 2009
... Monocentric City TIAN Qiong School of Economics and Management Beihang University Beijing, 10... more ... Monocentric City TIAN Qiong School of Economics and Management Beihang University Beijing, 100191. China. tianqiong@buaa.edu.cn HUANG Haijun School of Economics and Management Beihang University Beijing, 100191. China. hjhuang@nsfc.gov.cn ...
This paper deals with the riding behavior of commuters who take trains from a living place to a w... more This paper deals with the riding behavior of commuters who take trains from a living place to a work place during morning rush hours. The total travel cost include early and late arrival penalties as well as carriage body capacity. An equivalent mathematical programming model which generates equilibrium riding behavior is presented. The number of actually chosen transit runs, passenger
Proceedings of the 2009 International Joint Conference on Computational Sciences and Optimization, CSO 2009, 2009
This paper proposes a time-dependent network equilibrium model in a mixed-mode network with P&... more This paper proposes a time-dependent network equilibrium model in a mixed-mode network with P&R facilities to investigate the effects on travelers' choice of time-varying price of the P&R. An equivalent variational inequality (VI) problem is formulated to capture all the components of the proposed model in a time-dependent multi-layer framework. A numerical example is used to illustrate the application of the proposed model and solution algorithm.
ABSTRACT This paper investigates how the local authorities could efficiently regulate the public ... more ABSTRACT This paper investigates how the local authorities could efficiently regulate the public transit, which is operated by a private firm. Both the waiting time at stops and the in-vehicle congestion costs are taken into account to reflect the transit service quality. The Pareto-efficient frontier is derived and three types of regulation strategies, namely Price-cap, Return-on-output and Quantity control, are analyzed and compared. On one hand, although the Price-cap regulation can attract more demand effectively, the private firm will inefficiently supply a lower frequency to keep the cost down. On the other hand, both the Return-on-output (ROO) and Quantity-control regulations are Pareto efficient that can keep the transit system operating along the Pareto-efficient frontier. Especially, Quantity-control regulation seems to be more attractive than ROO as there is no need for the firm’s accounting information. In addition to the investigations on regulation, a new optimal demand-frequency correspondence is also derived that extends the Mohring’s “Square Root Principle” in incorporating transit in-vehicle congestion effects.
It is known that the commonly used NaSch cellular automaton (CA) model and its modifications can ... more It is known that the commonly used NaSch cellular automaton (CA) model and its modifications can help explain the internal causes of the macro phenomena of traffic flow. However, the randomization probability of vehicle velocity used in these models is assumed to be an exogenous constant or a conditional constant, which cannot reflect the learning and forgetting behaviour of drivers with historical experiences. This paper further modifies the NaSch model by enabling the randomization probability to be adjusted on the bases of drivers' memory. The Markov properties of this modified model are discussed. Analytical and simulation results show that the traffic fundamental diagrams can be indeed improved when considering drivers' intelligent behaviour. Some new features of traffic are revealed by differently combining the model parameters representing learning and forgetting behaviour.
2008 International Conference on Intelligent Computation Technology and Automation (ICICTA), 2008
ABSTRACT This paper formulates a dynamic user equilibria model that incorporates the traffic cong... more ABSTRACT This paper formulates a dynamic user equilibria model that incorporates the traffic congestion based on the flow-density fundamental diagram. By using Greenshieldpsilas speed-density relationship, we derive the analytical solution, which is different with not only the traditional static BPR function but also the classical bottleneck model result. In the free regime, the equilibrium cost is a power function of the total demand, which is more similar to the BPR function. While in the congested regime, the equilibrium cost is a monotonic increasing linear function of the total demand and larger than bottleneck model equilibrium cost.
2017 International Conference on Service Systems and Service Management, 2017
This Congestion tolls provide an efficient way to mitigate traffic congestion. In deterministic n... more This Congestion tolls provide an efficient way to mitigate traffic congestion. In deterministic networks, an optimal routing of traffic can arise as a user equilibrium by levying marginal-cost toll. In reality, traffic demands vary day in day out. The uncertainty of demand brings difficulties to design transport policies in theory and to implement the traffic coordination in practice. The expected travel budget is defined by involving the mean marginal-cost toll into the expected travel time, and a equilibrium model is established. We compare the expected social cost of the equilibrium and the system optimum to find the efficiency loss of the marginal-cost toll. It is found that the network performance degrades as demand variation goes up. Thus the control of demand variation could be an effective assistant tool to improve the efficiency of congestion pricing policies.
Transportation Research Part E: Logistics and Transportation Review, 2021
Abstract This paper examines the morning commuting flow patterns in a many-to-one public transit ... more Abstract This paper examines the morning commuting flow patterns in a many-to-one public transit line. Multi-class commuters with different degrees of sensitivity towards crowding are considered. At user equilibrium, trains arriving at the destination at approximately the work start time are found to be either more or less congested at the intermediate stations, depending on the spatial distribution of commuter class at each station. In addition, the system optimal crowding fare is found to be train-dependent and may fluctuate over time at each station. Finally, the theoretical properties of morning commuting flow patterns and crowding fare are illustrated through numerical examples.
2009 International Conference on New Trends in Information and Service Science, 2009
... Monocentric City TIAN Qiong School of Economics and Management Beihang University Beijing, 10... more ... Monocentric City TIAN Qiong School of Economics and Management Beihang University Beijing, 100191. China. tianqiong@buaa.edu.cn HUANG Haijun School of Economics and Management Beihang University Beijing, 100191. China. hjhuang@nsfc.gov.cn ...
This paper deals with the riding behavior of commuters who take trains from a living place to a w... more This paper deals with the riding behavior of commuters who take trains from a living place to a work place during morning rush hours. The total travel cost include early and late arrival penalties as well as carriage body capacity. An equivalent mathematical programming model which generates equilibrium riding behavior is presented. The number of actually chosen transit runs, passenger
Proceedings of the 2009 International Joint Conference on Computational Sciences and Optimization, CSO 2009, 2009
This paper proposes a time-dependent network equilibrium model in a mixed-mode network with P&... more This paper proposes a time-dependent network equilibrium model in a mixed-mode network with P&R facilities to investigate the effects on travelers' choice of time-varying price of the P&R. An equivalent variational inequality (VI) problem is formulated to capture all the components of the proposed model in a time-dependent multi-layer framework. A numerical example is used to illustrate the application of the proposed model and solution algorithm.
ABSTRACT This paper investigates how the local authorities could efficiently regulate the public ... more ABSTRACT This paper investigates how the local authorities could efficiently regulate the public transit, which is operated by a private firm. Both the waiting time at stops and the in-vehicle congestion costs are taken into account to reflect the transit service quality. The Pareto-efficient frontier is derived and three types of regulation strategies, namely Price-cap, Return-on-output and Quantity control, are analyzed and compared. On one hand, although the Price-cap regulation can attract more demand effectively, the private firm will inefficiently supply a lower frequency to keep the cost down. On the other hand, both the Return-on-output (ROO) and Quantity-control regulations are Pareto efficient that can keep the transit system operating along the Pareto-efficient frontier. Especially, Quantity-control regulation seems to be more attractive than ROO as there is no need for the firm’s accounting information. In addition to the investigations on regulation, a new optimal demand-frequency correspondence is also derived that extends the Mohring’s “Square Root Principle” in incorporating transit in-vehicle congestion effects.
It is known that the commonly used NaSch cellular automaton (CA) model and its modifications can ... more It is known that the commonly used NaSch cellular automaton (CA) model and its modifications can help explain the internal causes of the macro phenomena of traffic flow. However, the randomization probability of vehicle velocity used in these models is assumed to be an exogenous constant or a conditional constant, which cannot reflect the learning and forgetting behaviour of drivers with historical experiences. This paper further modifies the NaSch model by enabling the randomization probability to be adjusted on the bases of drivers' memory. The Markov properties of this modified model are discussed. Analytical and simulation results show that the traffic fundamental diagrams can be indeed improved when considering drivers' intelligent behaviour. Some new features of traffic are revealed by differently combining the model parameters representing learning and forgetting behaviour.
2008 International Conference on Intelligent Computation Technology and Automation (ICICTA), 2008
ABSTRACT This paper formulates a dynamic user equilibria model that incorporates the traffic cong... more ABSTRACT This paper formulates a dynamic user equilibria model that incorporates the traffic congestion based on the flow-density fundamental diagram. By using Greenshieldpsilas speed-density relationship, we derive the analytical solution, which is different with not only the traditional static BPR function but also the classical bottleneck model result. In the free regime, the equilibrium cost is a power function of the total demand, which is more similar to the BPR function. While in the congested regime, the equilibrium cost is a monotonic increasing linear function of the total demand and larger than bottleneck model equilibrium cost.
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