Recently, some preliminary researches examining the speeding reduction effect of advisory intelligent speed adaptation on community roads have been implemented in Japan. However, there are seldom previous studies related to community roads without the posted speed limit. Since the number of this type of community roads in Japan is countless, speed reduction methods by infrastructures such as humps or constrictions are difficult. Therefore, the strategy of speeding reduction is very important. To fill this gap, this study examines the speeding reduction effect of advisory intelligent speed adaptation on community roads without posted speed limit considering vehicle movement and roadside environment. The probe data of 10 elderly and 10 nonelderly drivers living in the urban area of Toyota City, Japan are analyzed here. These probe data were collected through one long-term social experiment. The major finding suggests that 1) the advisory intelligent speed adaptation can reduce the speeding behavior of elderly drivers, compared to non-elderly drivers; 2) this reduction effect does not have the relation with the existence of walking road or residence in the roadside.
According to “Tourism-based Country Promotion Plan” by Japanese Government, both public- and private- sector promote various projects related to tourism. In some areas on the other hand problem of congestion by pedestrian in the streets of tourist area becomes serious. This research was held to survey pedestrian behavior in the fields which has various characteristics of pedestrians with certain tendencies of walking purpose to collect data on walking speed, pedestrian density and traffic capacity of pedestrians and then compare between tourist-dominated pedestrian area, commuter-dominated area and other area with specific characteristics of people. The research reveals that tourist people walk in group, stop for a while, and walk slowly much more than commuter people and thus pedestrian traffic capacity in unit width in tourist-dominated area is smaller than in commuter dominated area. This result indicate specific strategies and standards for pedestrian route planning and street-designing are required for tourist-dominated pedestrian area and its surroundings.
The urban expressway in Japan is charged with the distance based toll based on the principle of redemption of construction costs. It is possible to set various toll patterns between on lamp and off lamp for urban expressway. In the study, a method to search for the toll pattern of urban expressway which maximizes travel time reduction benefit of the whole road network is developed. The optimum toll pattern is expressed by a combination of various parameters. In order to find the optimal solution, it is necessary to calculate of an enormous combination with the traffic assignment model. Therefore, in the study, the ant colony optimization which is one method of metaheuristic algorithm is applied. This algorithm models the behaviour of finding a path from ant herd to the food. By applying ant colony optimization technique, the optimal toll pattern of urban expressway can be calculated with less calculation time is shown.
In addition to the conventional "running, turning and stopping", attention is gaining attention as "connecting" as one of the new functions of the car. This "connection" function is expected to be further utilized in cooperative ITS in which both road-to-vehicle and inter-vehicle communication systems work together. In addition, it is thought that the importance of the prefetching information that provides the range that can not be acquired by the car alone when practicing the inter-vehicle communication will be further enhanced. In this study, as an example of a road-to-vehicle / inter-vehicle communication service, the difference of influence of traffic congestion end information by road-to-vehicle communication and acceleration / deceleration information of a preceding vehicle due to inter-vehicle communication on driving behavior of a driver was compared using DS . As a result, it was suggested that by providing acceleration / deceleration information, it contributes to urging the driver to drive safely and to contribute to improving safety awareness of the driver by providing congestion end information.
This study focuses on optimal pattern of spacing between marking lines of speed reduction markings (SRMs) installed on straight lane adjacent to transition curve section, in order to induce vehicles to reduce their speed safely before entering the curve. The aim of this study is to show evidence of how the spacing pattern of SRMs should vary according to the curve radius, considering a change in curve radius affecting the vehicle speed in the absence of SRMs, based on causal inference by a difference-in-differences method incorporating an instrumental variable method using field experiment data. Our findings are summarized as follows: In the case of relatively small radius of curvature (300 m in this study), the deceleration effect of pattern End, which is the pattern of spacing with greater decrease ratio (DR) between the lines in end section than in beginning section on the SRM-installed lane, is higher than that of pattern Beginning for drivers who are driving at the speed of about 90 to 100 km/h or at about 100 to 110 km/h. In the case of relatively large radius of curvature (600 m), the effect does not significantly differ between pattern End and pattern Beginning for the drivers.
The bus bunching problem that two or more buses move as platoon in the peak hour is often observed on urban bus routes. That causes of the accumulated delay of bus operation. In the study, the bus operation method to avoid the bus bunching. The descriptive model is created to evaluate the condition of bus moving for the particular bus route. The frequency of buses, the defined speed and passengers in the bus stops are determined to describe the condition of bus operations. It is described that the excessive boarding passenger demand to the particular bus stop causes of the bus bunching. It might be regulated in Japan that the bus driving order cannot be changed even in the bus bunching. Therefore, another bus operation method with bus taking over is proposed in the study. The empirical study is carried out to evaluate the effectiveness of the proposed method with the observation database for the real bus route.
Recently, based on the guideline for bicycle plans by Japan national government, bicycle traffic network plans are formulated in many local cities in Japan. There are many types of road space for bicycle traffic in bicycle traffic network plans, such as bicycle path, bicycle lane on roadway, marking on roadway and walkway allowed for bicycle use. Furthermore, identification methods of the types of road space for bicycle traffic in bicycle traffic network plans are different in each local city and they are not same as the guideline by national government. Characteristics of road conditions and characteristics of bicycle use are different in each local city and they are not same as the situation in the guideline by national government. In this study, types of road space for bicycle traffic and identification methods of them in bicycle traffic network plans in each local city have compared each other and they are compared with the guideline by national government.
Since the beginning of the 21st century, the word “Anshin” has become more and more wildly used. The English meaning of Anshin means peace of mind, freedom from care, relief, and so on. Japanese public transportation operators often set goals for passengers’ comfort according to Anshin definition. However, it remains difficult to estimate such an achievement, understanding relationship between operators’ strategies and passengers’ feelings. This research targets subway passengers by means of an interview. First, the definition of Anshin is explained, then the structure of subway passengers’ Anshin is clarified. Finally, the operators’ measures making passengers feel Anshin is examined by means of picked up advertisements on safety and manner among promotion of Anshin measures by business operators, and verified whether they are connected with Anshin for users. As a result, it became clear that the Anshin of the user in the subway can be shown quantitatively from the degree of Anshin of the individual elements contributing to it. Regarding advertisements, there is no effect of self improvement of Anshin, but it became clear that there is an effect to arouse attention and interest.
Delivery vehicles of relief supplies mainly pass through emergency roads. Roadside buildings and bridges on the emergency roads are maintained for earthquake resistance to carry out emergency activities after large scale disaster. On the other hand, secondary roads of connected emergency roads and shelters are necessary to deliver relief supplies because all of shelters are not faced emergency roads. However, unlike emergency roads, there are no guidelines of earthquake resistance for secondary roads of connected emergency roads and shelters. Therefore, even in the past large scale disaster disruptions, secondary roads affected accessibility to deliver relief supplies. In this study, secondary roads between emergency roads and shelters were analyzed considering road block factors under the prerequisite of delivery of relief supplies by vehicle. In addition, it is considered the concept of road improvement to ensure the accessibility to the shelters before disaster happened. Furthermore, the usefulness of the concept was verified.