Planning of distribution facility, strengthening logistics functions, and designing a distribution network are essential to improving the efficiency of the logistics in the global economy. In order to do that, it will be important to understand the flow of goods. It is possible to understand the interregional trade that type of transportation mode and goods from distribution census data and gross traffic data in Japan. However, we can't understand the flow of goods via warehousing facilities. Distribution Centers with a warehousing function have an important influence on the flow of goods from production to consumption. This paper describe the logistics chain model, which split the production – consumption flow between direct goods and goods via warehousing facilities.

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Probe person survey by smartphone is expected to serve as a research method that gathers large-scale travel behavior of individuals in a flexible manner. In this study, we developed a method to identify transportation mode from movement history data such as GPS data that is automatically collected, with the aim of improving research methods by automatic transportation mode identification. We propose a simple discrimination technique for practical application and verify its discrimination accuracy by using the movement history data collected by the probe person survey by smartphones in practice. It is shown that more than 80% of transportation mode is identified accurately by the technique even using various movement history data from various participants. We consider the utility of the method from the verification results and describe the direction of practical use.

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This paper shows a new approach to estimate parameters of pedestrian behavior model. The approach applies general state space model. In this modelling, parameter estimation is formulated as a sequential Bayesian filtering. Thus we can estimate time varying parameters which are adaptive to sequentially acquired data. Also we can deal with observation errors. Firstly we include parameters into state vectors of a general state space model and formulate an estimation equation. Secondly we define components of that model: state vector, observation vector, system model, observation model and initial distributions. Then we apply this settings to data acquired at a railway station and estimate time varying parameters. We compared estimation results with estimation settings; we discuss effects of initial distributions, variance of random walk parameters and observation accuracies. In addition, we compared estimated parameters with real situations and confirm that parameters are adaptively changed to congestions.

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The purpose of this study is to consider the relationship between the leisure activities and the feeling of happiness of aged person. We find that aged person can be classified into three leisure activity types of the "various type", "average type" and "passivity type". We use LSI-Z (Life Satisfaction Index Z) as the index of happiness, and analyze the correlation between four leisure activity types and LSI-Z. In conclusion, (1) general leisure activity satisfaction is the important element for the feeling of happiness of aged person; (2) the existence of the friends and time, and the health condition of the person improve the general leisure activity satisfaction.

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In this study, to estimate the selection tendency about the passing position and direction of movement of a bicycle, the traffic analysis and the Logistic regression analysis of bicycle traffic were conducted. Consequently, it turned out that the selection of a bicycle user's passing position is subject to the influence of a bicycle user's individual attribute, bicycle type, structure of a road, existence of parking vehicles, and the situation of traffic. And about the direction of movement, the structure of a road, existence of parking vehicles, and the situation of traffic had affected it.

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As you can see, there are many styles of implemented bicycle spaces in Japan, but some spaces are inappropriate for cyclists. One of those examples is that the safety problem of cyclists on narrow two-way cycle track are considered for a long time. In response to this problem, cycling on carriageways is being encouraged especially in the urban districts. However, we don't have the detailed guideline of bicycle facility design especially in intersections which is available for various attributes or purposes of cyclists and is also adequately-considered for vehicle drivers. In addition, the bicycle facilities on carriageway are likely to be hardly accepted because most of cyclists believe that they can ride bicycles more safely on sidewalks than on carriageways. Therefore, we need to examine various road designs and traffic situations to make clear what type of bicycle facilities are safer and more comfortable for cyclists and develop them.
Cycling simulators have gotten a lot of attention recently as one of the usable tools for above mentioned problems and we developed a new cycling simulator (“Morics”) which is available for not only traffic safety education but also safety analysis among other traffic modes. Then, the validity of experimental results with the simulator is one of the most important issues for safety analysis and dependent on the validity of traffic situations and bicycle control.
We conducted simulator experiment for the safety analysis in terms of the passing behavior on twoway cycle track and evaluated 2.0m-width two-way cycle track safety in terms of the passing behavior on two-way cycle track.

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Purpose of this research is to clarify the validity of the Mobility Management by examining the process of attitude change episode type MM and analyzing what are affecting the consciousness to the bus. Episode type MM has the persuasion process of the occurrence by the effect of positive emotions which has been demonstrated in social psychology as background theory. This is the theory that if positive emotions evoked about the subject, after the emotional thinking, and there is a possibility that a positive attitude cause the subject transformation. Emotional message was edited the assumption that based on the episode that was collected at the actual bus, tell the charm of a public space of the bus, to evoke positive feelings for the bus. From results of this study, it is expected that carried out MM intended behavior change in the Minoh. Further, providing motivational information is positioned within the various methods of MM. Thus, From the result of this research that episode type MM can affect consciousness about attitude change, it can be expected that more episode type MM is conducted.

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In this study, we point out the fact that in Japanese road networks, there is no structured system; with a built-in intermediate speed category, in which a travel speed exceeding 50 km/h is included. Considering this situation, we tried to construct a simple model having three classes of road networks in which intermediate speed roads are added on a general road and expressway. We then performed calculations based on the model, and demonstrated a scope of application for an intermediate speed category and its effectiveness.

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The Ministry of Land, Infrastructure, Transport and Tourism (MLIT) and the National Police Agency (NPA) published “Guidelines for creating a safe and comfortable bicycle friendly environment” in 2012. These guidelines adopted a policy that bicycle networks should be created mainly by bicycle lane type, and shared space on carriageway when traffic volume is low and vehicle speed is slow. An evaluation system from a viewpoint of bicycles is needed in order to clear the condition for the comfort of cyclists. The aim of this study is to build evaluation models from a viewpoint of bicycles' safety perception by developing the Probe Bicycles System, which can monitor the speed and position to the cyclist of the vehicle which pass es through the bicycles.

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Tokaido Shinkansen the world's first high-speed rail opened in 1964, and its fiftieth birthday comes around in 2014. Several high-speed lines have been constructed up to current times, however, the Shinkansen network development has been affected by rigid economic rationality of severe social environment since the oil shock and is not active even in these days that the role of high-speed rail attracts worldwide attention. The present network is a result of trunk railway policy after privatization and separation of the Japanese National Railways.
In this study, trunk railway network was optimized by genetic algorithm on the premise of population distribution in 2025 and passenger flow OD in 1990. Japan's trunk railway policy of recent 25 years will be discussed based on comparison study with the present main line network to the search results of GA.

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The proof service of the Demand Bus was implemented for the purpose of the cancellation of the public transport blank and bus transit convenience improvement form December, 2012 in Kawahigashi district and Wakamatsu district that are located in Kitami city, Hokkaido. And full-scale service is implemented now. This Study elucidated users consciousness structure before and after introduction of Demand bus by CS portfolio analytical method. As a result improvement of the satisfaction for the bus service and changes of users consciousness structure was elucidated. Furthermore, refinement for continuous service was extracted and specific improvement plans was examined.

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Many pedestrian accidents were occurred at the mid-section of the road. Elderly persons need to have longer time in crossing the crosswalk. Therefore, wrong decision increase the risk of traffic accident at the last half of crosswalk. Two stages crossing by utilizing the safety island in the medium could be effective to solve this problem. Pedestrians do not have to cross the crosswalk continuously because pedestrians could stop at the safety island. Moreover, pedestrians do not have to confirm both side of the road at one time. Pedestrians only have to check right side until they arrive at the safety island, and they only have to check left side of the road at the safety island. This could improve pedestrian safety and could bring efficiency. In this paper, in order to confirm this assumption, video image was recorded at the crosswalk. Result of simulation analysis clarified the advantages of two stages crossing.

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Efforts for ensuring traffic safety on school roads such as cooperative urgent inspections are deployed increasingly in response to sequential traffic accidents which result in child casualties on the way to and from school. Safety measures for children should have to be carried out according to children's stage of development in consideration of the limited capability of movement and the immaturity of perception and decision. On the other hand, there is not enough quantitative and objective knowledge about the children's ability to adapt to real traffic society to implement and evaluate safety measures appropriately. In this study, the prevention of a road crossing accident, a typical case of children's pedestrian accidents, is focused and the authors verified the children's ability of road crossing decision against the distance and velocity of the approaching vehicle on the community road, taking an experimental approach for elementary school students. It has been found from the observation of the crossing decision that the elementary school students are not able to decide to cross the road taking the velocity of the approaching vehicle into account properly as the adults.

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This paper discusses the discrepancy of trade statistics and an estimation method for international freight flows based on trade statistics. The problem of the discrepancy is defined as differences between trade flows reported as imports and the same flows reported as exports. Many researchers and organizations treats the problem mainly focusing on the value data in trade statistics, and do not deal with quantity data in detail. In this paper, we review existing studies about the discrepancy of trade statistics, and analysis characteristics of the discrepancies by using trade statistics in Asia, especially focusing on quantity data. This study shows utilizing quantity data of trade statistics gives useful knowledge to adjust the discrepancies. Furthermore, this study examines an estimation method for international freight flows based on trade statistics. Accuracy of the estimations is influenced by data discrepancies in trade statistics. This study evaluates the estimations calculated from adjusted trade statistics.

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In the rural areas of Japan where public transportation is limited and inconvenient, people with limited mobility including an elderly and people with walking disabilities have constraints in their travel. For solving this problem, the new public transportation option, for example Demand Responsive Transport (DRT) system, has been introduced in these areas. However, there are barriers to use this system because the users have to reserve trip in a curtain time and origin and it's difficult to get many users there.
In the other hand, in Southeast Asian metropolis, there are various types of attractive transportation system namely “Paratransit”, which many people generally use in their daily life. Focusing on the case study of “Silorlek” in Bangkok, we have initially found that its high-frequency service and small size vehicle are major characteristics to attract its customers.
Therefore, in this study, we conducted the experiment of high-frequency service transportation in the hill-slopes rural area with limited public transportation in Japan and evaluated its performance. Particularly, the hill-slopes area with narrow roads and limited public transportation was selected as the study area. Most of trips are short-distance shopping trip. From questionnaire survey, we identified that the high-frequency service can encourage people to use the public transport system.

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Most of the studies about railway route choice behavior have been based on the decision-making theory applied to the two processes; arranging alternatives and choosing from the choice set. This paper focuses on the first process, preparation of choice set, which has not been fully understood. We used the dataset from our original survey responded by 1217 railway commuters in Tokyo metropolitan area. First, we examined the existence of route captive passengers who did not choose their commuting rail lines but decided inherently. It is found that those captive passengers have a dominant alternative in terms of the level of service. We conclude that those individuals had to be excluded from the dataset. Most of the other travelers who have compensatory alternatives in their choice set can be regarded as selective decision-makers and included in the analysis. Second, we compared the routes arranged in the choice set with the ones not included in the choice set. Based on calculating the difference and ratio of service level between two routes, we could infer the thresholds which control whether each route alternative is included in the choice set or not. Moreover, passengers consider total travel time, fare, number of transfers, and congestion rate when they arrange alternatives as a choice set. These two results help us to arrange route choice alternatives before modelling the behavior of railway commuters.

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As a basic step to consider the planning of school-commuting roads based on CPTED, this study proposes a model to describe the relationship between the crimes targeting junior high-school children and the influence factors given to them. Since the most of these crimes belongs to the opportunity crime, this model is based on the hypothesis that the encounter with target and the environmental factors around the school-commuting roads influence criminals.
As the result of the application to actual situations, the model provided reasonable predictions for distribution of likelihood of crime incidence according to the distance from school. In addition, we can quantify the influence of the encounter with the target and environmental factors given to the criminals.

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A number of annual traffic fatalities in Japan are continuously decreasing in the past 13 years. However, increasing proportion of traffic accidents occurring at streets, which have narrow widths and spread living places, has become bigger problems recently. For a reason that the streets have spread to a wide area in cites, the counter measures to focus on area speed managements are useful. In recent years, the National Police Agency in Japan has decided to promote area speed limit called Zone 30, for example. We think that it is extremely important to smoothly develop such safety measures for the streets as soon as possible. In this study, from the viewpoint of the land use and the ideal performance that is basically required as a street, methodology for selecting area speed management areas were proposed through the case study of Toyota City.

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More than forty years have passed after establishment of Nationwide Shinkansen Railway Development Act and some parts of the first plan have gradually been getting under construction. But Japan's recent improvement scheme of trunk railway is different from European countries. Japan's framework contains only construction of brand-new high-speed line. There exists exceptional method as widening of truck gauge, high-speed line with narrow gauge, or truck upgrading of conventional line, however, it is not clear that to what extent combination of these methods can improve the network.
In this study, trunk railway network was optimized by genetic algorithm on the premise of population distribution in 2040 and passenger flow OD in 2010. As a result, modifying of improvement scheme can revitalize interregional exchange on trunk railway network and augment its diversity.

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Driving simulator (DS) has been making use of for the evaluation of road facilities, information scheme and so on recently, as it has an advantage in making flexible, safe and cost effective experiments. DS has however the characteristic of perception error of speed, distance, and so on. The aim of this study is to make clear the performance of the developed bicycle simulator with wide screen from the viewpoint of real perception reappearance of speed, distance. As results, speed in DS tends to be felt slower at about 50%, distance in DS tends to be felt shorter at about 50% than real situation, but time perception in DS seems to be compatible to real world . Sight distance for signage becomes short by the low resolution of display.

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The Jogjakarta economy is largely dependent on education and tourism industry. The emerging dominance of private transport has reached to a degrading traffic conditions. Severe traffic congestions and high level of air pollution have been affecting the attractiveness of Jogjakarta, a popular tourism city in Indonesia. Unless a new approach of urban transport system development, it is feared that the amount of visitors will keep declining and hence affecting the city economy. In response to the increasingly complex issue of providing effective and efficient transport systems, the Ministry of Transportation (MoT) of Indonesia enacted decree No 51 of 2007, promoting pilot cities for land transport improvement. From the target of thirty pilot cities by 2014, to date, twenty seven cities have signed a memorandum of understanding with MoT and launched more than twenty new transit systems, including TransJogja of Jogjakarta. The aim of this study is to explore international tourist perceptions of new urban bus service regarding quality of service, information and English language guidance, satisfaction, and willingness to use TransJogja. The findings from path analysis reveal the important attributes that influence customer satisfaction and willingness to use new urban bus service. According to model results, rather than service quality, the information and English language factor is the main concern for international tourists using Trans bus. As concerns over the willingness to use urban bus, both operator and transport authority should provide with the updated and supplemented information in English to cover international tourist and visitor needs. The model results can be useful both to operator and transport authority to analyze the correlation between individual attributes of the service delivered and identify the more important attributes for improving the provided service.

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The purpose of this study is to clarify how cyclists behavior and consider the on-street bicycle lane in day and night time where the sidewalk are also permitted to ride by bicycles. From the observation survey, it is indicated that the share of using bicycle lane is changed among different roadway structure like road surface condition, and the share of using sidewalk by bicycle is increased by about 10% in average. From the questionnaire survey , it is indicated that cyclists feel the deterioration of visibility of roadway surface color and traffic signs at night. However, those changes have not affected cyclists' behavioral change such as shifting to the sidewalk from the on-street bicycle lane , because they might rather care their visibility from cars and tend to keep larger distance from cars by riding in sidewalk.

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Although community buses should pass narrow roads to ensure accessibilities of residents, they are not welcomed considering traffic calming and traffic safety in residential area. At first, this study showed that the most difficult element in the stage of service route planning is to obey the criteria of road width, however, there are several places not satisfying this criteria on the actual service routes. This study showed that the reason why those places were permitted was strongly affected by the traffic volume and the situation of the road such as existence of passing places. Finally this study proposed the concept of a new indicator for community buses not determined by the width of road only.

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Traffic accidents with cyclists who know the rules but violate them are considered as one of social problem, but the methodologies to safety education for cyclists has remained to be defined. So in this study, we revealed the effects and the feasibility -reproducibility of cycling behavior with law violation, especially- of the experience-based education program using a cycling simulator "Morics1". As the results, the effects of the safety education programs depend on the accident experience itself and the evaluation of "Morics1". We conducted the experiment survey with that after the braking system was improved, and it was revealed that the safety education program with the cycling simulator can make those who know the rules to reproduce the behavior with the law violation.

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Hokkaido contributes to Japan in terms of food supply and the self-sufficiency is 190%. Recently, road evaluation tries to introduce the local characteristics and food transport is focused on in Hokkaido. However, the conventional analysis is not quantitative or not network level. Besides, the statistics of Food OD data does not exist. This study established the methodology to evaluate the road network quantitatively based on the function of food transport and introduced the indices which describes the function of food supply such as [calories] and [provided population].
Food OD table was estimated to describe the flow of food as “from field to consumer” consistently based on statistics. This study proposes three types of outputs, network evaluation, route evaluation and transport index. Network evaluation can describe which route transports many foods quantitatively by various indices such as weight, price, calorie and provided population. Route evaluation can describe the composition of foods, producing place and stage of distribution by route and by direction. Transport index can measure the split f food transport among road types and the effects of construction of new road.
This study can describe the situation in which traffic volume is few, but there are trucks transporting many foods which feed millions of Japanese people.

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In cooperative ITS, “Connecting” has been drawing attention as one of the new functions of the vehicle in addition to conventional functions such as ”running”, ”turning” and “stopping”. In this study, we looked into the effect of providing the acceleration and deceleration information of the pre-preceding vehicle to the following vehicle on the fuel consumption rate and the driving behavior in starting as forward- looking case study of inter-driver connections by the provision of information. As a result, the following matters were found: 1. Fuel consumption rate was improved. 2. With the provision of information, changes in driving behavior such as shortening the starting delay and decreasing the accelerator pedal input were confirmed. 3. In finishing acceleration, the vehicle behavior harmonized with the preceding vehicle behavior. From the above results, it was clarified that the provision of information has effects in starting.

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The concept of car sharing is becoming popular all over the world because it greatly lessens environmental impact and provides individuals with an alternative transportation mode. One-way car sharing is convenient because users can access vehicles in one depot at any time and then return them to another. This “one-way car sharing” has spread globally. However, problems can arise, mainly as a result of the uneven distribution of vehicles, which can make it impossible to reserve a vehicle in some locations.
In this research, we set out to verify the possibility of introducing one-way car sharing by creating a model of such a scheme, which we applied to an analysis of the scheme's operation. The results of our study revealed that the scheme will be most efficient when the number of allocated vehicles is equal to approximately half the capacity. We also confirmed the reduction in the environmental impact.

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New laws to commit illegal parking confirmation affairs to private sector were enforced in 2006, June. To prove effectiveness of this new law for illegal parking, the effect of new law on traffic accidents with parked car concerned was analyzed, to utilize traffic accident data and illegal parking regulation data gathered by National Police Agency. Traffic accidents with parked car concerned consist of two types, accidents with parked car, main accident occurrence reasons are course change by parked car or intercepting visibility by parked car. To check traffic accidents with parked car concerned between 2005 and 2013, after the enforcement of new law for illegal parking, number of traffic accidents with parked car concerned were decreased more rapidly than number of all traffic accidents. Traffic accidents with parked car concerned and high speed vehicle, this type of accidents in night time and accidents with parked car and two-wheeled vehicle or bicycle were decreasing drastically, so decreasing rate of traffic accidents with parked car concerned is higher, when traffic accidents with parked car concerned are likely to occur. Decreasing rate of traffic accidents with parked car did not depend on parking inspector.

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Early and precise incident detection contributes early provision of information and incident handling to mitigate negative impacts of traffic incidents. Automatic incident detection algorithm has been introduced as freeway incident management system to detect incidents more early and precisely. Several conventional studies developed incident detection algorithms using observation data from roadside traffic detectors. However, it is difficult to install traffic detectors in the entire road networks because of their costs of installation and maintenance. Probe vehicle data enable us to observe traffic flow state. It is expected that the incident detection can be utilized without traffic detectors. This study developed incident detection algorithm based on shockwave theory. By using the probe vehicle data, the algorithm detects tail of congestions and estimates capacity reduction at the bottleneck. The detection rate and false rate of the models are examined using a traffic flow simulator, and the performance measures of the proposed methods are compared with those of previous methods.

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Because of the withdrawal of commercial facilities and the aging society, it will be more difficult for some of us to do shopping at the commercial facilities in the future. Some cities have already introduced “the shopping support services” to solve the difficulties. This study examined current state and factor analysis of intention of using the shopping support services. Results showed the following: 1) people who wanted to relocate their living places would change their mind not to relocate if some additional services were available along with the mobile catering; 2) elderly people would use the online shopping if someone taught them how to use it; 3) some people would use the shopping support services if the contents of services were improved, but others would be adamantly opposed to using it whether the contents of services were improved or not.

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The traffic capacity of roundabout is conventionally defined by the traffic volume on circulatory roadway at the cross-section of the entry point. However, not only the traffic at the cross-section of circulatory roadway, the other factors such as traffic flowing out to the same approach with the corresponding entry point may have influence on it.
This study investigates the vehicles' entry behaviors on the basis of the vehicle trajectory data and aims to quantify the influential factors on traffic capacity of roundabouts. First, the lags and gaps are rigorously defined by considering the driver's viewpoint. Then, we develop a model to estimate the probability that a vehicle enters the circulatory roadway by applying discrete choice model. Finally, the impact of the flowing out vehicles on the traffic capacity is numerically analyzed.
The findings of the study is as follows: i) the vehicles flowing out to the same approach also have significant influence on the vehicles' entry behavior, implying that the conventional definition of traffic capacity would overestimate the capacity, and ii) if such vehicles turn on the direction indicator in flowing out to the approach, it may significantly contribute to increase the traffic capacity of roundabout, because a driver of an entry vehicle can anticipate the behavior of the flowing out vehicle in advance and accordingly he/she quickly enter just as the vehicle goes out.

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Advanced driver-assistance systems which provide visual information to encourage safe-driving or eco-driving have attracted lots of attentions, and some functions have been already embedded in smartphone applications or car-navigation systems. Although some public road experiments have been performed both domestically and abroad, there are not so many researches and developments with respect to the systems to explicitly encourage smooth following behavior to prevent a traffic jam occurrence. Therefore, the present study aims to develop the driver-assistance system which encourages the drivers to keep a constant headway-time in order to prevent the traffic jam occurrence. This manuscript, as the first report of the study, proposes a visual information interface to display a target headway-time (2.0 seconds), a real-time information about actual headway-time, and a frame whose color and line width change according to the gap. Moreover, driving simulator experiments are conducted to verify the effectiveness of the proposed system on the prevention of the traffic jam occurrence.

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Whether there is a change in the operation of the driver by the information of voice navigation provided by utilizing ITS is analyzed in this study. Specifically, when the vehicle approaches the signalized intersection, the driver is provided with the information of voice navigation that signal light shortly changes into red. The comparison between a signboard which is a wide-ranged way for the prevention of collision at the intersection and a voice navigation which is a user-designated one is focused in this study. We come to the conclusion that the vehicle can stop safely at a signal intersection by providing information of voice navigation.

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This paper presents the concept of a new transportation system, Smart Access Vehicle System. In the system, the locations and routes of all vehicles are controlled by a computer, and no fixed routes or time-tables are necessary. We call it “transportation cloud”. The system responds to new demands in real time and provides utility of taxis with cost efficiency of buses. Furthermore, it can flexibly readjust to traffic congestion, accidents, malicious weather and disasters. We conducted operation tests and succeeded in running the system automatically for several days.

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The objective of this study is to clarify a relationship between the road traffic conditions and accident frequency through statistical model analysis towards implementing effective safety measures. A rich accident database was combined with relevant road traffic information by using GIS software, and two different models, i.e. negative binomial regression and multiple regression models were independently applied for estimating accident frequency. As a result, it was found that accident frequency is closely related to average travel speeds and distance between intersections in arterial roads. Regarding non-arterial roads, the result specified different influencing factors by accident type. Furthermore, it suggested a high potential of frequent accident occurrence in non-arterial roads particularly at positions close to the arterial roads with low average travel speed. Finally, the necessity of improving quality of traffic flow and hierarchical road network for road safety was discussed.

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The rat-run traffic in community roads is a big problem in terms of traffic safety. Physical devices for traffic calming, such as chokers and speed humps, have been used to deal with the problems. However, these measures can't exclude rat-runners from community roads, that is, these are not fundamental solutions for rat-running. The authors focused on the rising bollard, which has prevailed in European countries. The rising bollard prevents cars from going through a closed road against the traffic regulation but allows specific vehicles with authority to pass through the road by making its steel bollard go down automatically. The system had not been introduced on public roads in Japan.
In a previous study, the authors proposed the soft rising bollard, which equips a flexible soft bollard so that cars and the bollard are not damaged when the cars crash the bollard accidentally. In this study, the soft rising bollard were installed tentatively in a shopping mall where the road was closed to cars in a part of a day; it was the first time that the rising bollard worked on a public road in Japan. The authors assessed the safety in use on the public road, the efficiency in encouraging car drivers to follow to the traffic regulation, and acceptance of the system by the general public. From camera surveillances, it was found that the numbers of cars that pass the road against the traffic regulation reduced after the installation of the soft rising bollard. Questionnaire surveys to citizens displayed a high rate of positive opinions about the soft rising bollard. In conclusion, this study revealed the soft rising bollard is an effective measure to deal with rat-running problems in Japan.

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This paper tries to apply seasonal adjustment methods based on Hierarchical Bayesian estimation to clarifying a mechanism of capacity bottleneck phenomena in basic section (i.e., access-controlled section). For the purpose, first, homogenous traffic flow data in a sag section in terms of characteristics of car-following behavior is collected by so-called ‘self-iteratively following-the-leader method’ on driving simulator. Second, the obtained traffic flow data is converted to time headway data. Third, prior distributions are defined satisfying following three prior knowledge: the smoothness of time headways of successively running cars, a slight change of time headways of an identical car in chronological order and a small change of the mean of time headways in platoon in chronological order. The result of an implementation trial shows that the seasonal component reflects the effect of longitudinal alignment on traffic flow.

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Access roads of transfer points, such as railway stations, can be a bottleneck due to conflicts between different road users coming to the transfer stations. Congestions from the bottleneck may propagate to other arterial roads. Kiss-and-ride vehicles, as one of the user types, are able to choose their stop positions freely on the access road, while their characteristics and how they affect on congestions are unknown. The purpose of this research is to clarify the relationship between stop position choice behavior of picking- up or dropping-off vehicles and queueing patterns at the access road, and to build a simulation model which quantitatively represents the queueing phenomena. From the survey data analysis, it was found that distribution of stopping duration varies by time of the day and the double parking of vehicles with relatively shorter stopping duration causes queue occurrence. The proposed simulation with stopping position choice including double-parking maneuver was able to represent various queueing patterns at the access road.

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Weaving section is one of the major bottlenecks in urban expressway network and also known to hold high risk of accidents due to its complicated vehicles movements. The main cause of the above problems is the concentration of vehicles' lane change position and timing in a weaving section. This study assumed fully-controlled condition and proposed vehicle deconcentration control algorithm in a weaving section of urban expressway. The effects of this algorithm was examined using microscopic traffic simulator. As a result, this algorithm showed better performance than the current traffic situation, that is, it is expected to increase the capacity and to alleviate the congestion of the weaving section.

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In this study, we propose a preference elicitation mechanism to reduce users' cost of bidding each time slot in transportation service auction. This mechanism use the relationships of each time slot's private value and interpolate the bidding values which are not stated by users. This research shows the mechanism can reduce the number of bidding. Finally, we evaluate the performance of the preference elicitation mechanism in transportation service auction and the result of numerical simulations indicates that this preference elicitation mechanism works efficiently in cases where user's desired time slot is concentrated.

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The Securing of the fairness and efficiency will be required to design the service of public transportation. Especially, about local transport, the target areas and policies should be clarified, because of the limited public burden. In this study, the potential public transport demand is quantified by using Data Envelopment Analysis (DEA). And by using the results of the estimation, improvement priorities and benchmark sets will be clarified. In addition, the development model is applied to Rikuzentakata city (Iwate pref.), and we studied for potential to implement the model by the case study approach.

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In recent years, signal control based on movement is introduced on a trial basis in several intersections. However, effective traffic conditions to reduce traffic congestion by introduction of signal control based on movement are not clear. In this study, traffic simulation model of signalized intersections is constructed to estimate traffic congestion related with signal control system. Then, signal control based on movement and signal control separated for pedestrians are compared. To clarify the effective traffic conditions for signal control based on movement, time fluctuation in traffic volume and difference of traffic volume with opposite direction are focused in the analysis.

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In conducting performance-based design of road, an index of measure-of-effectiveness plays an important role. Currently, travel speed is suggested as the measure-of-effectiveness, because smooth access to activity bases is a purpose of road development, and a dominant factor for smooth movement under the condition if safe driving is guaranteed. However, driver is forced to pay attention and is strained under ever-changing traffic condition to maintain safety. This fact means that the forced efforts for maintaining safety should be evaluated adequately.
This study develops a measure-of effectiveness index for evaluating traffic function of road sections from a view point of accessibility to activity bases. The index is formulated as an aggregated point-basis evaluation focused on both safety and smoothness, The calibration of the proposed model is made by using driver's subjective evaluation data to the driving environment collected from experiments with driving simulator. A procedure to estimate the value of index from traffic counter data is also developed. Through a case study, the proposed index shows a better description ability than those of current measure-of-efficiency index based on travel speed.

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Intelligent speed adaptation (ISA) which has been attracted in European countries has the possibility to be a drastic tool for traffic calming in Japan. This study at first developed the speed selection model considering both the safety and convenience, and then the model was estimated using the data from the driving experiment. Next, the drivers' burdens and the benefit of death accident reduction were calculated and compared based on the speed selection model and the crash risk evaluation model where the virtual community street segments were assumed. It was then found that the benefit of introducing mandatory ISA with the 30km/h limit surpassed the burdens when more than one dart-out pedestrian accident had averagely been occurred per one kilometer per two years in the current situation.

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It is well known that the causes of traffic congestion at expressway sag sections are mainly vehicles' speed reduction caused by road gradient changes and imbalance use of lane. Currently, several congestion countermeasures, which provide information to drivers, are conducted to eliminate these causes. However, is not necessarily clear how the lane changing behavior in high traffic flow rate affects the occurrence of traffic congestion. This study aims to analyze the relationship between lane changing behavior and the occurrence of deceleration wave by using spatiotemporal trajectory data extracted from video images. Moreover, some simulation study is conducted, which compares the travel time between normal drivers and aggressive drivers who drives a car in a hurry by changing their lanes frequently. Finally, congestion mitigation approaches which utilize ITS are discussed.

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Travel speed is one of the typical traffic performance indices of intercity expressways. In order to apply the performance based road planning and design procedures to inter-city expressways, it is a prerequisite to estimate sectional travel speed based on the speed performance relationships in different road, traffic and environmental conditions. However, the impact of road alignments on the speed performance has not been well understood and there remains much work to formulate the speed performance relation-ships. This paper aims to analyze the impact of grade and its length on speed performance based on the observational data obtained from vehicular detectors with an emphasis on relationship between grade and speed. The analysis result will provide useful information in applying the performances based road planning and design procedures.

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In recent years, field operational tests and implementation of roundabout are actively promoted at several places in Japan, and roundabout has been legally positioned through the amendment of the Road Traffic Act in June 2013. Entry capacity is one of the most important indices for performance evaluation related to the application of roundabouts. However, a criterion of entry capacity including impacts of pedestrians and cyclists based on the observation has not been available in Japan due to the limited observation examples. This paper aims to analyze characteristics of roundabout entry traffic flows based on the field data observed at several existing and/or experimental roundabouts. Entry capacity observed at Roppontsuji roundabout in Karuizawa Town is also examined and compared with the estimated values by a proposed entry capacity estimation model.

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An accident risk is considered to be affected by a brightness change of the road, especially when a vehicle is travelling at twilight time or around tunnel sections. In this study, Poisson regression analyses are carried out to investigate the impact of the brightness change on traffic accident risk. The accident record and the traffic counts on expressways in Shikoku Island from 2007 to 2010 are used in the analysis. As a result, it is shown that traffic accident risk is significantly higher both when a vehicle travels at the night time and when a vehicle travels on the tunnel exit section at the daylight time or at the twilight time.

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This study examined a method for evaluating the risks caused by snowstorms on winter roads, based on visibility data. Visibility and other meteorological data, and driving speed and other driving behavior data are provided by mobile meteorological observation vehicles at times of blowing snow. The conditions that contribute to reductions in roadside visibility at the time of snowstorms were also analyzed.
It was found that driving tends to be affected by the change of average visibility and not affected by rapid deterioration of visibility. To be more specific, poor visibility causes reductions in driving speed because brakes tend to be applied more at average visibilities of less than 200 m and the standard deviation of steering angle tends to be greater at average visibilities of less than 100 m. It was also found that there are cases in which the average visibility deteriorates at the ends of bridges, at the ends of snow fences and at openings in snow fences. With respect to road structure, the average visibility tends to be lower at fills and flat land than at cuts.

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Car sharing is considered as one of the ways to familiarize the electric vehicle (EV) when popularization is not progressed. However, EV has the demerits such as a long time to charge and travel distance per charge is shorter than gasoline vehicle. Therefore, the possibility of car sharing using EV is unclear compared with gasoline vehicle. This research develops a car sharing system suitable for small businesses by a pilot study. We investigated operational procedure taking into account of the characteristics of EV by Monte Carlo simulation analysis. Analysing appropriate number of members according to different operating hours and travel distances, It was found that the frequency and operating time of a shared EV increased by limiting distance and time.

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