This paper focuses upon the optimal repairing policies of public facilities under demand uncertainty. An optimal impulse control model is formulated to determine the optimal sequence of impulse timing and intensities to minimize the present values of expected costs. The optimal repairing rules can be formulated as a set of adaptive rules by which whether repair should be carried out or not can be judged based upon the routinely observed data on functional deterioration levels of the facilities. A numerical example illustrates how adaptive rules can be calculated in a given demand environment.

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Paying attention to the various advantageous characteristics of the railway, Japan has been providing a great deal of assistance through the Official Development Assistance (ODA) for railways in developing countries, so as to enable the railways in these countries to sufficiently play their roles as important social infrastructures. However, many of the railway in developing countries are not always sufficiently satisfying such demand, and are not fully playing the inherent roles expected. Under these circumstances, measures for improving Japanese ODA in the railway sector were drawn up and proposed.

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Unlike commute trips, business trips are generated throughout business hours, and several destinations tend to be visited in a trip chain. In this study, a route and departure time choice model for a business trip chain is developed based on the hypothesis that the trip chain is made so as to minimize the total cost, including costs associated with other business activities before and after the trip chain, as well as costs associated with travel time, toll fees, and the probability of being late. The empirical analysis is carried out using a data set obtained from a survey of business trip drivers. The properties of the estimated model are examined on a sample case

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The objective of the present study is to find solutions for transportation problems using a theoretical framework related to social dilemmas. The present study proposes a definition of social dilemmas specific to infrastructure planning, and discusses how strategies for solving social dilemmas, which have been investigated empirically and theoretically in sociology and social psychology, can be applied in transportation planning. This study indicates that what is seriously required for solving transportation planning is not only TDM or TCM but also policies to activate public spirits of transportation system's users, and that practical and scientific researches to understand how we can activate the pubic spirits, are essential for transportation planning.

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This research analyses theoretical aspects on DSO (the Dynamic System Optimal assignment) and the ramp control using a simple network with parallel freeway and arterial. First, the dynamic marginal cost, which plays an important role in the dynamic analysis, is defined and several queuing patterns in DSO are described. Second, based on the DSO discussion, the ramp control strategy is analyzed. It has not been known whether the ramp control can indeed reduce the total travel time not only on the freeway but on the arterial, since the control basically decreases capacity of a link on a network. However, the analysis reveals required conditions and the optimal strategy so that the ramp control can effectively reduce the total travel cost.

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It is thought that alliance between air carriers is one of the most effective strategies for surviving international aviation market. Furthermore, allied carriers change their network structure, which also bring changes of level of service to travel for international passenger. Therefore, the influence of alliance should be analyzed from the perspective of social welfare. In this research, two kinds of subjects in international aviation market are considered. One is passenger who is independently classified by their nationalities. Another one is international air carrier which is also independently classified by their attributes. Behavior models of each subject are formulated on the assumption that passengers behave to maximize their utilities and that carrier behave to maximize their profits, and. The effects of code-sharing, cost-sharing and network complement are evaluated using market equilibrium analysis.

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The objective of this paper is to find clues for improving inefficient traffic condition caused by deluded equilibrium (Nakayama. et. al, 1999). With this aim, a day-to-day dynamic traffic simulation model was developed. The simulation model comprises a traffic simulator and a simulator of driver behaviors. The latter simulates the driver's learning of route choice strategies. The results of simulation analysis indicate that providing traffic information and the reducing road capacity in roadways of which traffic volume is excessive, are efficient means for breaking drivers' negative beliefs and improving the inefficiency in deluded equilibrium.

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The methodology for weighting endogenous samples is extended in this study and applied to a multi-dimensional choice-based sample. It is shown that a unified weight exists for samples obtained from complex endogenous sampling schemes. Problems with conventional weighting methods for samples from endogenous sampling, such as roadside surveys, are pointed out and an improved weighting scheme is proposed. Coefficient estimates of discrete choice models with and without weights are compared, and the importance of applying an appropriate covariance estimator is pointed out.

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Previous studies regarding splits in communication media suggest that communication complexity considerably affects media splits. In light of minimizing company expenses, we have proposed a media split model for inter-regional business communication. This model lies between one time face-to-face communication and multiple telecommunication. Communication complexity for each OD pair is described by the Weibull distribution function and reflects demographic factors. The media split model demonstrated a better fit for inter-regional trips and telecommunication than the conventional gravity model. Further, simulation analysis established that differences in communication complexity distributions generate differences in elasticity among OD pairs.

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This study aims to analyze the impact of the introduction of the Post-Panamax container cargo vessel to the international maritime transport market. In the developed model the perfectly deregulated market is assumed and the market is consisted in two participants; the liner ship companies and shippers. Applying the developed model to the 2010 Asian-Pacific-European maritime transport market, the impact of the introduction of the Post-Panamax vessel is forecasted. Thorough the numerical computation, the introduction of Post-Panamax vessel leads the service route network to the hub and spokes shaped transport network. And through some scenario studies, the impact of each port management policy is discussed.

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A hazard-based duration model of household vehicle transactions behavior is developed in this study to examine the effects of Japanese periodic inspection program, and an empirical analysis is carried out using the data set obtained by a panel survey conducted in Kyoto City. The results of model estimation suggest a higher probability of replacing or disposing of a vehicle whose inspection is scheduled within the next 6 months. Results of a simulation-based scenario analysis indicate that raising in the inspection cost accelerates the replacement of vehicles households own without affecting the number of vehicles they own, and that the extension of the inspection period decelerates the scrappage of vehicles and increases the number of vehicles households own.

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Linear motor carriage has the merit which is easy to automate and right-angled drive. In case of container conveyance as applied, it contributes to an efficiency and labor saving at a port container terminal. So, we designed a cargo handling system using linear motor carriage, and evaluated it by a series of numerical simulations. We obtained the following result. (1) Linear motor specification: It is required 7m/s speed and 1.5m/s² acceleration. (2) Cost evaluation: We made cost target of cargo handling machine clear, in order to be same with the conventional terminal. (3) Capability evaluation: It is possible to increase efficiency of stevedoring and carrying in or out. After all, we made a precondition clear for applying linear to the terminal.

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As comparing to plain track, turnouts are under severe condition such as impact wheel loads and so on, the number of sleepers designed in turnout is larger than that in plain track in the same interval. But no design standards has been made according to decide the pitch of sleepers in turnout. In this study, the rail deflections and steel sleeper, the limited beam model on the elastic support theory evaluated stresses of this turnout. Using the turnouts designed by this way and constructed in railway yards the deflections and stresses were measured under condition of a running locomotive. The results were within allowable limits and it was confirmed the improved turnout could be used in operating lines.

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