Hai-jun Huang | Beihang University (original) (raw)

Papers by Hai-jun Huang

Procedia - Social and Behavioral Sciences

This paper investigates the efficiency and equity of morning peak ramp control schemes in a freew... more This paper investigates the efficiency and equity of morning peak ramp control schemes in a freeway corridor with limited capacity. In terms of efficiency, both short-run and long-run optimal ramp control schemes are obtained by minimizing the total travel cost and maximizing the total social benefit along the corridor. It is found that for a short-run optimum with inelastic demand, the morning peak period is of the same duration for different on-ramp locations. But for a long-run optimum with elastic demand, the peak duration for various on-ramps increases with the local capacity elasticity of demand. In terms of equity, two measures are defined from a demand-based viewpoint and a space-based viewpoint. It is shown that the short-run optimal ramp control scheme is perfectly fair from a demand-based equity viewpoint. Consequently, two typical ramp control schemes—a perfect demand-based equity scheme and a perfect space-based equity scheme—are introduced and compared with the long-ru...

Networks and Spatial Economics

This paper makes a contribution to the literature by bounding the travel time inefficiency of the... more This paper makes a contribution to the literature by bounding the travel time inefficiency of the logit-based stochastic user equilibrium (SUE) under Advanced Traveler Information Systems (ATIS). All drivers are divided into two groups, one equipped with ATIS and another without, and both of which follow the logit-based SUE principle in making route choices. The equipped drivers have less degree of travel time variability than the unequipped ones. The inefficiency of the two-user class SUE is defined in two different ways, i.e., in comparison with the SO in terms of total actual system travel time, or in comparison with the corresponding SSO in terms of total perceptive system travel time of all users. The effects of various parameters on the bounds are further investigated. It is found that the inefficiency bound against the SSO is only dependent upon the degree of link congestion and independent of the network topology. In contrast, besides the effect of the degree of link congest...

Public Transport

This paper investigates how the local authorities could efficiently regulate the public transit, ... more 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-frequen...

Transportation Research Part B Methodological

In this paper, we study various parking management schemes in a many-to-one network, where each o... more In this paper, we study various parking management schemes in a many-to-one network, where each origin is connected to the destination by a highway with a bottleneck and a parallel transit line. First, we derive a model to compute the morning commuting pattern when the destination has inadequate parking space to accommodate potential private cars. Second, we propose and compare the following three schemes of distributing parking permits to commuters residing in different origins: uniform, Pareto improving, and system optimum distribution of parking permits. Third, free trading of parking permits among commuters in a free market is introduced to better cater for commuters' parking needs. Numerical examples show that parking permits distribution and trading are very efficient in traffic management.

International Joint Conference on Computational Sciences and Optimization, 2011

We study the properties of traffic flow coming from free flow to congested flow on a two-lane roa... more We study the properties of traffic flow coming from free flow to congested flow on a two-lane road by using cellular automaton traffic model. A new boundary condition is proposed, which exhibits the reason of the relation that traffic flow against on the injected probability. The simulation results show that the traffic never comes into congestion even if there are

2011 Fourth International Joint Conference on Computational Sciences and Optimization, 2011

Third International Conference on Natural Computation (ICNC 2007) Vol V, 2007

Lecture Notes in Computer Science, 2005

Transportation Research Part B: Methodological, 2015

Transportation Research Part B: Methodological, 1992

Transportation Research Part B: Methodological, 2011

ABSTRACT In this paper, we study various parking management schemes in a many-to-one network, whe... more ABSTRACT In this paper, we study various parking management schemes in a many-to-one network, where each origin is connected to the destination by a highway with a bottleneck and a parallel transit line. First, we derive a model to compute the morning commuting pattern when the destination has inadequate parking space to accommodate potential private cars. Second, we propose and compare the following three schemes of distributing parking permits to commuters residing in different origins: uniform, Pareto improving, and system optimum distribution of parking permits. Third, free trading of parking permits among commuters in a free market is introduced to better cater for commuters' parking needs. Numerical examples show that parking permits distribution and trading are very efficient in traffic management.

Transportation Research Part B: Methodological, 2011

It is well known that the use of advanced traveler information systems (ATIS) can alleviate traff... more It is well known that the use of advanced traveler information systems (ATIS) can alleviate traffic congestion and enhance the performance of road networks through guiding commuters' route and departure time choices. It has also been recognised that ATIS can help destination and activity choices in determining why, where and when various activities are engaged in. This pa- per attempts

Transportation Research Part B: Methodological, 2007

Procedia - Social and Behavioral Sciences

This paper investigates the efficiency and equity of morning peak ramp control schemes in a freew... more This paper investigates the efficiency and equity of morning peak ramp control schemes in a freeway corridor with limited capacity. In terms of efficiency, both short-run and long-run optimal ramp control schemes are obtained by minimizing the total travel cost and maximizing the total social benefit along the corridor. It is found that for a short-run optimum with inelastic demand, the morning peak period is of the same duration for different on-ramp locations. But for a long-run optimum with elastic demand, the peak duration for various on-ramps increases with the local capacity elasticity of demand. In terms of equity, two measures are defined from a demand-based viewpoint and a space-based viewpoint. It is shown that the short-run optimal ramp control scheme is perfectly fair from a demand-based equity viewpoint. Consequently, two typical ramp control schemes—a perfect demand-based equity scheme and a perfect space-based equity scheme—are introduced and compared with the long-ru...

Networks and Spatial Economics

This paper makes a contribution to the literature by bounding the travel time inefficiency of the... more This paper makes a contribution to the literature by bounding the travel time inefficiency of the logit-based stochastic user equilibrium (SUE) under Advanced Traveler Information Systems (ATIS). All drivers are divided into two groups, one equipped with ATIS and another without, and both of which follow the logit-based SUE principle in making route choices. The equipped drivers have less degree of travel time variability than the unequipped ones. The inefficiency of the two-user class SUE is defined in two different ways, i.e., in comparison with the SO in terms of total actual system travel time, or in comparison with the corresponding SSO in terms of total perceptive system travel time of all users. The effects of various parameters on the bounds are further investigated. It is found that the inefficiency bound against the SSO is only dependent upon the degree of link congestion and independent of the network topology. In contrast, besides the effect of the degree of link congest...

Public Transport

This paper investigates how the local authorities could efficiently regulate the public transit, ... more 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-frequen...

Transportation Research Part B Methodological

In this paper, we study various parking management schemes in a many-to-one network, where each o... more In this paper, we study various parking management schemes in a many-to-one network, where each origin is connected to the destination by a highway with a bottleneck and a parallel transit line. First, we derive a model to compute the morning commuting pattern when the destination has inadequate parking space to accommodate potential private cars. Second, we propose and compare the following three schemes of distributing parking permits to commuters residing in different origins: uniform, Pareto improving, and system optimum distribution of parking permits. Third, free trading of parking permits among commuters in a free market is introduced to better cater for commuters' parking needs. Numerical examples show that parking permits distribution and trading are very efficient in traffic management.

International Joint Conference on Computational Sciences and Optimization, 2011

We study the properties of traffic flow coming from free flow to congested flow on a two-lane roa... more We study the properties of traffic flow coming from free flow to congested flow on a two-lane road by using cellular automaton traffic model. A new boundary condition is proposed, which exhibits the reason of the relation that traffic flow against on the injected probability. The simulation results show that the traffic never comes into congestion even if there are

2011 Fourth International Joint Conference on Computational Sciences and Optimization, 2011

Third International Conference on Natural Computation (ICNC 2007) Vol V, 2007

Lecture Notes in Computer Science, 2005

Transportation Research Part B: Methodological, 2015

Transportation Research Part B: Methodological, 1992

Transportation Research Part B: Methodological, 2011

ABSTRACT In this paper, we study various parking management schemes in a many-to-one network, whe... more ABSTRACT In this paper, we study various parking management schemes in a many-to-one network, where each origin is connected to the destination by a highway with a bottleneck and a parallel transit line. First, we derive a model to compute the morning commuting pattern when the destination has inadequate parking space to accommodate potential private cars. Second, we propose and compare the following three schemes of distributing parking permits to commuters residing in different origins: uniform, Pareto improving, and system optimum distribution of parking permits. Third, free trading of parking permits among commuters in a free market is introduced to better cater for commuters' parking needs. Numerical examples show that parking permits distribution and trading are very efficient in traffic management.

Transportation Research Part B: Methodological, 2011

It is well known that the use of advanced traveler information systems (ATIS) can alleviate traff... more It is well known that the use of advanced traveler information systems (ATIS) can alleviate traffic congestion and enhance the performance of road networks through guiding commuters' route and departure time choices. It has also been recognised that ATIS can help destination and activity choices in determining why, where and when various activities are engaged in. This pa- per attempts

Transportation Research Part B: Methodological, 2007