The Honshu-Shikoku Bridges are expected as life bridge for daily trips and as sightseeing bridge for round tour trips. On the other hand, although the daily traffic on Honshu-Shikoku Bridges is automatically measured day by day, but that data have not been utilized effectively.
This paper aims to analyze a change of traffics and the interaction of bridges by using the daily traffic data Holiday arrangement data and rainfall data are included in analysis. As a result, traffic are affected by the holiday arrangement, and there are round tour trip occurred between the east and west bridges. Furthermore these features are changing with the years.

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A past study by the authors proposed a method to estimate maritime freight flows using metric tons and the twenty-foot equivalent unit (TEU). In order to clarify the accuracy of the estimation method, this paper describes the characteristic of the existing freight flow statistics shown in Japan, Indonesia and Hong Kong, and the characteristic of the estimation results for those three countries/regions. From the relation between the characteristic of statistics and the characteristic of estimation results, the authors show that the accuracy of the estimation results is not different from existing statistics.

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While bus traffic is following the situation of a decline, many policies corresponding to various needs has been performed in order to improve it. Especially the bus information system is achieving success. The basis of such a background, merit and demerit are examined from the existing bus location system and as a practical system, the bus information system which had usability, reliability, and stability with it was built. Moreover, it tried to find out the technique for the improvement in accuracy of “ bus time-of-arrival prediction” which is the main function of the built system.

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The objective of this study is to discuss the probability for introducing the information services to the “ Stop-and-go” merging sections at arterial roads by conducting field experiment of information system. Firstly, the possible procedure and contents of information service are discussed. Secondary, simple prototype of information system is applied to the actual merging sections and we confirm that the information service can reduce driver's decision time if information content is similar to the driver's feeling. Finally, the safety condition of the merging section can be improved by the information service.

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The service of the Electric Toll Collection (ETC) system in Japan started in 2001. However, the numbers of car installed ETC device remain stagnant. In this research, ETC is featured as an applicable case. Using diffusion model on the mechanism for deployment and using simulation analysis in evaluating the effect of measures for deployment improvements were done. It confirmed that reduction in the price of ETC device is influential in the rate of installation than the discountoll charge or etc.

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This research has developed a traffic signal control algorithm that directly measures the delay of each vehicle using ITS sensing technologies such as AVI sensors. The algorithm automatically updates signal parameters to minimize the total delay. Through the experiment, the algorithm shows the good performance in terms of the improvement of total delay, even though the traffic conditions which may be affected by the demand profiles or the saturation flow rate of each link are widely varying We are planning to have a real-world experiment and examine the effectiveness under the real traffic conditions.

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Traffic congestion is one of the major concerns of road users. But only few information is provided by the road administration. The performance measurement is thought to be important for road sectors to be accountable for policies and projects. In this relation, outcome index for the traffic congestion from the viewpoint of road users is also important. The purposes of this paper are, firstly to develop the recording system of the driver's judgment on congestion by using PC, secondly to find major factors affecting the congestion recognition of drivers as well as passengers, and lastly to develop congestion judgment model.

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In this paper we analyzed several traffic surveys and two types of questionnaires for execution of park and bus ride system in a big sports event in Toyota city. From the Covariance Structure Analysis it indicated that the waiting time and the travel time of shuttle bus influenced on satisfaction degree of P&BR users in this evening sportsevent.

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In this paper, we have proposed and solved theoretical model to analyze the optimal commuting and work start time distributions under flexible work hours (FWH) with peak-load pricing (PLP) considering modal split between road and railroad. In the results, we have shown that the optimal work start time distributions satisfied necessary condition are 9 patterns which are the combination of each 3 patterns for automobile and railroad commuters. From numerical examples, furthemore, we could have confirmed that the modal split is change, and evaluated economic effects of the FWH with the PLP.

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We present a methodology for estimating the benefit of Variable Message Signs (VMS) projects, one of the components of ATIS. Using the logit model, the expected utility theorem and the option price concept, we develop a simple methodology to estimate the benefits of the provision of information. Furthermore, we extend the model in order to calculate the benefit of information considering safety and sensitivity analysis is carried out for determining the changes of value of information with respect to different variables and functional forms.

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This paper discusses how to estimate the expectations and the variances of section travel times with sample vehicle trajectories, such as probes. Since the individual travel time of a section may differ from each other, an advanced travel information service (ATIS) should provide not only the accurate expectations of travel times but also the accurate variances. The accuracy of that information depends on the number of available probe trajectories. However, especially in low penetration ratio of probes, it is difficult to expect sufficient samples which traverse the whole section. Therefore, we should consider utilizing fragmentary trajectories which traverse some part of the section. In this paper, we describe the methodology of travel time estimation with fragmentary probe trajectories. Then the accuracy of the estimation is validated with computational experiment by changing sample ratio and sampling strategies.

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This study proposed the introductory effect of advanced traveler information systems using two methods, WTP and [MSUE/ATIS] model. First, we performed the citizen perception survey to the introductory effect of VICS-unit. We evaluated the value of MIS by WTP survey, and estimated the benefit Furthermore, the unknown parameter of [MSUE/ATIS] model was estimated using WTP model. Finally, [MSUE/ATIS] model was applied to Kumamoto Urban Area and Seien Urban Area in order to estimate the benefit. We found that the introductory of MIS in the area, where traffic congestion is heavy and travel cost is large, is effective.

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We make an analysis of vehicles' behavior and their decision-makings at the merging points on the public road and the expressway. In this paper, we examine the factors and the mechanism of gap choice behavior of merging vehicles and the difference between the public road and the expressway, in which the traveling velocities and the lengths of merging points are largely different. Then, we construct a fuzzy model of gap choice behavior based on the analysis results. Also, we investigate the spots where the vehicles turn the wheel and start merging or changing the lane, and make its fuzzy model.

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This paper presents traffic conflict analysis and proposes a new conflict indicator for developing ITSassisted traffic safety system under congested and high-speed traffic environment. The conflict analysis is carried out using a Vehicle Tracking System using a digital VCR developed by the authors. After reviewing the previous works of the traffic conflict analysis, the significance of the traffic conflict analysis is stated using hazard and risk concept that associates traffic conflicts with traffic accident occurrences. Next, the conventional traffic conflict indicators, such as TTC, approximate-TTC, PET, etc. are demonstrated. The characteristics of these conflict indicators are discussed. Then, based on these discussions, the requirements for desired conflict indicators for truly appropriate and effective to alert drivers under congested and highspeed traffic are discussed for ITS-assisted safety system. Finally, PTTC indicator as a new conflict indicator for congested traffic is proposed and demonstrated for an actual traffic conflict.

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In this Paper, The purpose of this paper is to investigate the factors affecting saturation flow rate of left-turn traffic. The actual conditions and characteristics of pedestrians/bicycles at the conflict area where pedestrians/bicycles and left-turn vehicles cross are clarified in order to quantify the behavior of pedestrians/bicycles. The model devised in this study is expected to contribute to the development of signalized intersection planning.

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It is necessary to take into consideration the influences to surface road conditions in considering the traffic control on urban expressways. In this research, traffic simulation model on Osaka-Sakai Route of Hanshin Expressway is extended for evaluating the effects of traffic control on urban expressways to surface road conditions. In this model, traffic volumes and travel times on surface road network are estimated by user equilibrium assignment with the detour traffic from urban expressway. Thereby, the effects of traffic control strategies on urban expressway can be evaluated within the urban road network using the constructed simulation model.

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The planning of traffic safety countermeasures in urban road network is considered as a combinational opturnzation problem for the means and the spots of safety countermeasures to be introduced. It can be formulated as a bi-level mathematical program with traffic network equilibrium constraint. Application of immune algorithm (IA) to solving this optimization problem approximately is examined in this research. The optimization process of immune algorithm is discussed in comparison with genetic algorithm (GA). In this way, it is shown that immune algorithm is an effective algorithm to solve the combinational optimization problems in planning of traffic safety countermeasures.

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This paper discusses the proper way to evaluate the reproducibility of traffic conditions with dynamic traffic simulation, and proposes one methodology using Wavelet Analysis, which based on the quantification of the similarities of time-series of simulation result to the reference data. At first, the problems in the evaluation with correlation coefficient or route mean square error are discussed. Then, the new indicator based on wavelet-analyis is introduced. By using wavelet coefficient, we will be able to evaluate the errors with desirable level of time resolution, and to consider the quality of observed data. Finally, this paper proposes a policy for the evaluation of simulation studies to contribute to the ‘Best Practice Manual’ for the standardization.

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In order to make effective plans of comprehensive traffic safety measures including the application of ITS technology, it is important to evaluate objectively the risk of traffic accidents for road sections. The microscopic data on vehicular movements required for the analysis are extracted from video data using the image processing technique. Especially, the objective indices to evaluate traffic conflicts are used for the analysis of the risk of vehicle collision at a weaving section. As an initial stage for developing a microscopic traffic simulation, this study analyzes the speed adjustment processes of the vehicles in the lane-changing situation.

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This study aims to identify the causes of traffic congestion around Takarazuka-Higashi Tunnel, Chugoku Expressway by analyzing the phenomena of traffic flow. This section includes several structural features such as sag alignment, contiguous tunnels, and merging and diverging lanes of an interchange that may contribute to multiple causes of capacity reduction and involve complicated traffic phenomena. This study made a detailed analysis of traffic phenomena such as traffic flow rate, travel speed, vehicle headway and platoon that had been observed by vehicle detectors and video cameras installed on several points inside and outside of the tunnel. The mechanism of congestion occurrence was discussed and modeled.

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In this Paper, we implemented a field experiment to provide information with respect to risks and costs of automobile use and psychological depression due to road traffic congestion, to 178 university students who were around 18 years old and who did not hold a driving license. The data obtained from the survey that was implemented 6 month after the intervention of providing the information indicated that due to the information provision, belief with respect to negative aspects of automobile use were strengthen, intentions or motivations to use automobile decreased, and the driving license holding behaviors were actually suppressed.

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