This issue comprises seven papers focusing on the transportation management and operation problems in Asia including road traffic (three papers: Alhajyaseen et al.; Meng and Weng; Ryu et al.), surface public transportation (two papers: Tu et al.; Kariyazaki et al.), and air transportation (two papers: Hirata et al.; Akebayashi and Ishikura). Their academic contributions and practical significances are summarized.
Existing signal control strategies do not consider pedestrian flows in optimizing signal parameters, which may impose significant delays on pedestrians. This study aims to investigate the rationality and effectiveness of designing signal coordination for pedestrians. A numerical case study in Japan is analyzed. Field survey is conducted to collect the geometric characteristics, signal timings and vehicular traffic condition information. In a parallel approach, the performances of signal coordination for vehicular and pedestrian traffic are estimated by using the vehicular traffic simulation tool Synchro/SimTraffic and the pedestrian simulation tool NOMAD. The results showed that the coordination for the major pedestrian flow led to a significant reduction in average delay (15%). Generally, it is concluded that the effectiveness of pedestrian signal coordination is not guaranteed but depends on the relationship between pedestrian platoon dispersion and the signal cycle length.
This paper aims to evaluate the effects of work zone configuration, traffic flow and heavy vehicle percentage on traffic delay at work zones by using a heterogeneous cellular automata (HCA) model. The activity area length and transition area length are two work zone configuration factors taken into account. The average traffic delay per work zone and the average traffic delay per 100m are the two indices used to express traffic delay at work zones. The graphical comparison results show that the transition area length has much bigger effects than the activity area length on traffic delay, especially in the light traffic condition. The function of average traffic delay per work zone is finally formulated that can be used to estimate the marginal effects of the activity area length, transition area length, traffic flow and heavy vehicle percentage.
Congestion pricing has been regarded as an effective method of reducing networkwide travel cost. Previous work on the toll-design problem focused on the deterministic network, assuming that the network operates deterministically without uncertainty. This essentially precludes investigating the recently proposed travel time reliability indices as a system performance measure to evaluate and prioritize the selection of future investment strategies. In this study, we investigate various recently proposed travel time reliability measures in determining the optimal toll strategies to improve travel time reliability in the network. A simulation-based genetic algorithm (SGA) procedure is developed to solve the stochastic bi-level programming problem. Our experimental results using a simple test network show that optimal toll determined by the misery index can improve both travel time reliability for network users and total travel time for the network planner.
The research focuses on comparative analysis of three popular types of bus lane operation including roadside exclusive bus lane, bus priority lane and ordinary lane. The analysis is firstly conducted based on simulation tests in PARAMICS with assumed data about traffic situations as well as input parameters. In order to evaluate the results more practically, the research introduces a case study. This case study is conducted at an urban street where there are large numbers of buses and high traffic volumes in Nagaoka City. The results show that with the current traffic situation, the bus priority lane type can help reduce the passenger travel time by 1.2 sec on the 500-meter long segment when compared with the current ordinary lane type. In terms of travel time saving, the paper finally figures out suitable areas for bus lane type applications under various conditions of the main road traffic volume and the number of passengers on the bus.
Small irregularities in service are leading to significant delays in the urban railway system of Tokyo, Japan, because the rail system is now operating very close to its capacity. The delay factor, however, varies by hour. The increase in train running time becomes the major cause of delay during peak periods because this has become longer than that of dwelling time. However, there is limited data availability concerning the behavior of train under the delay. So, the delay time increase due to interaction between trains is not properly accounted for. No research has yet been carried out to specifically examine a feasible operating method which can recover the knock-on delay early under high frequency operation. Therefore, this research formulated a train operation simulation model which reproduces the behavior of train operation. The simulation model is taking into account the interaction between the trains. Using the simulation model, this study attempts to understand the actual situation of train operation under the knock-on delay. Finally, this paper suggests a practical method to recover the knock-on delay earlier, which involves keeping a moderate separation between trains during running time.
The main purpose of the paper is to develop an analytical model for estimating runway capacity of Haneda airport in Tokyo which will have a new 4th runway in late 2010. The impact of the sequencing of the aircrafts’ departures/arrivals considering wake turbulence category was analyzed by using a more heuristic model which considers the feasibility of arrival spacing on final approach in practice. Haneda airport will eventually have two sets of open-parallel runways with crossing layout (16/34 L/R, 04/22 L/R). Consequently, the departure and arrival traffic will operate dependently with higher complexity than that of the current condition. By using the developed model, the necessary constraints on aircraft sequencing and spacing for attaining the runway capacity planned by the government and for expanding the capacity were analyzed.
This paper estimates the impact of the entrance of low cost carriers on the Eastern Asia international passenger transport markets, especially to the high density short-haul markets, and discusses the efficient management policy of a multiple airport system. We apply a bi-level air transport market model to Osaka-Korea international passenger transport market, and estimate the impact of entrance of low cost carriers. The results suggest that the entrance of LCC improves passenger’s utility, but the profit of legacy carriers is significantly reduced. We also evaluate the slot allocation policy of Osaka-Itami International Airport. Finally we find that the policy used in Osaka-Itami is useful for protecting the legacy carrier's share, but this effect disappears with the increase of passenger's sensitivity to airfare.