Hironao Kawashima

Two major programs and demonstrations in Japan (in-vehicle information systems)

Activities to promote development of in-vehicle information systems in Japan are described. Two major projects, Advanced Mobile Traffic Information and Communications System (AMTICS) and Road/Automobile Communication System (RACS), and their social backgrounds are described. Some of the results and findings of RACS experiments are briefly presented. The status of the projects and future problems in developing more advanced systems are indicated. >

A method for automatic detection of traffic incidents using neural networks

One of the most important aspects of traffic management systems is their ability to detect traffic incidents such as accidents, disabled vehicles, and obstacles on the road. The incidents affect highway drivers and cause traffic congestion, so an immediate and automatic detection method is desired. We think that the changes in traffic average in case of traffic incidents have certain patterns different from the normal case. Our research tries to detect traffic incidents immediately and automatically by using neural networks, which use one minute average traffic data as input, and decide whether an incident has occurred or not. To train the network we used traffic data from various locations where accidents had occurred and not. The former are generated by a micro simulator and the latter are collected by using ultrasonic vehicle detectors. To reduce the number of false detections so as to improve the process of training of the neural network, we added some data with similar average change patterns as observed when incidents occurred. As a result, we confirmed that adding enough combinations of similar average change patterns was very effective in increasing the recognition rate and to reduce the number of false detections.

JAPANESE PERSPECTIVE OF DRIVER INFORMATION SYSTEMS

A perspective view of of Japanese R&D activities of Driver Information Systems is given from the standpoint of developing joint projects by public and private sectors. First, a brief history of the R&D activities is illustrated from above mentioned standpoint. Then, two major projects, AMTICS and RACS, and the social backgrounds of these projects are explained. In order to give a clear idea of both projects some technical details are treated.Based on the history and the present status of the developments, the basic design conceptions of Japanese Driver Information Systems are explained and several factors or reasons which have influenced to the design conception are discussed. Then, the promoting systems of the R&D activities are generally explained and present status of the projects and future problems in developing more advanced systems are also handled. A brief discussion on the establishment of international standard is also mentioned as a final comment.

A practical solution using simulated annealing for general routing problems with nodes, edges, and arcs

A new practical solution of the general routing problems with nodes, edges, and arcs (NEARP) has been developed. The method is characterized by a primitive data modeling and a simple optimization procedure based on simulated annealing. The data structure of the method, that is traveling routes of a number of vehicles, is expressed as a string. The solutions generated by the proposed method are compared with those of another method by conducting computational experiments on instances of the NEARP. Moreover, it is shown that the proposed method is adaptable to additional conditions.

Application of Simulated Annealing to Routing Problems in City Logistics

The R & D activities to realize systems which provide road traffic information and route guidance have been conducted as core systems of Intelligent Transport Systems (ITS). However, the implementation of these systems will have less effect on freight transport unless logistics operation is rationalized in parallel to the development of ITS. On the other hand, according to the expansion of internet, information has been exchanged with extremely high speed and low cost. Nevertheless, goods must be moved in the real space. Ecommerce has caused the increase of door-to-door deliveries. The demands for high-quality delivery services such as small-amount high frequency deliveries with time windows have been made by many clients (including companies and individuals). The loading rate of trucks has decreased and the rate of freight transportation in total road traffic has increased. The rationalization in terms of increasing the loading rate and decreasing the total travel time is aimed not only for reducing operational costs in each freight carrier but also for relieving traffic congestion, saving energy and reducing the amount of CO2. Freight transportation in urban areas that is described above is called city logistics (Taniguchi et al. 2001). Many researches on routing problems have been appeared in the literature. Comprehensive and detailed explanations of theoretical models and solutions of them are given by Toth & Vigo (Toth & Vigo, 2002). On the other hand, in the context of city logistics, real routing problems should not be based under the assumption on the symmetry of the link costs of visiting customer j after customer i or customer i after customer j, pij=pji, and other related mathematical properties, as triangular property etc. This is due to the fact that in an urban environment routes using the streets have to account for one way streets, issues related to regulations at intersections. In addition, travel time might vary according to traffic conditions, that is to say, it might be time dependent. Moreover, in urban road networks, demands might be located on not only spots on streets but also streets themselves. This chapter is aimed for describing the original solution, which has been invented by the authors of this chapter, to routing problems in city logistics. At the beginning of this chapter, a variety of routing problems will be introduced and followed by the explanation of features of routing problems in city logistics. And then, a practical solution method, which is composed of a data model, transformation rules of a solution on the data model and an overall algorithm using Simulated Annealing for solving O pe n A cc es s D at ab as e w w w .ite ch on lin e. co m

VEHICLE ROUTING METHODS FOR CITY LOGISTICS OPERATIONS

Abstract A new vehicle routing and scheduling scheme associated with the actual delivery operations is developed. The scheme is characterized by a primitive data modeling and a simple optimization procedure based on the simulated annealing. The data structure of the scheme, that is, traveling routes of a number of vehicles, is expressed as a sequence of characters. The solutions generated by the proposed scheme are compared with the solutions given by other methods by conducting a computational experiment utilizing the bench-mark vehicle routing problems. It is shown that the proposed scheme is adaptable to additional constraints and objectives. Moreover, the scheme is applied to practical delivery problems.

A cognitive study of in-vehicle navigation systems: Applying verbal protocol analysis to usability evaluation

The drivers cognitive process when using an in-vehicle navigation system (IVNS) is investigated by means of verbal protocol analysis. Field experiments and laboratory experiments are employed. A concept of cognitive maps is used as the framework of the analysis. In the first stage, assuming that a person who is familiar with an area is the best navigator, communication between a driver and a navigator is observed. Three prototype IVNSs are designed, and comparative studies are conducted. The results indicate important factors in the design of the user-friendly interface of IVNS.

Fundamental study on effect of preceding vehicle information on fuel consumption reduction of a vehicle group

It is a concern that eco-driving vehicles, because their driving behavior differs from other vehicles due to e.g. e-start, may inhibit smooth traffic flow. Therefore, it is necessary to study the cooperative eco-driving done by a vehicle group, putting “vehicle-to-vehicle communication” and “road-to-vehicle communication” into perspective. Based on these factors, this study aimed to: 1) Analyze fuel consumption rates and driving behaviors of more than one vehicle following an Eco-Driving vehicle. 2) Examine the effect of information on the fuel consumption rate of the preceding vehicles on the following vehicles. As a result, the following findings were obtained: 1) By providing information to multiple following vehicles, the fuel consumption rate of the second vehicle was not lowered, while that of the third one was. 2) It is possible that, when information on fuel consumption of a preceding vehicle is provided to the following one, an inter-vehicular distance is shortened during deceleration to contribute to smooth traffic flow. From the above results, it is suggested that, when targeting a vehicle group, sharing the information on preceding vehicles is effective.

A PRACTICAL SOLUTION OF CAPACITATED ARC ROUTING FOR CITY LOGISTICS

Abstract A new capacitated arc routing solution associated with the actual delivery operations is developed. The method is characterized by a primitive data modelling and a simple optimization procedure based on the simulated annealing. The data structure of the method, that is, travelling routes of a number of vehicles, is expressed as a string. The solutions generated by the proposed method are compared with the solutions given by other methods by conducting a computational experiment utilizing the bench-mark capacitated arc routing problems. It is shown that the proposed method is adaptable to additional constraints and objectives.

Driver's characteristics for map information representation (North up map/heading up map) in navigation displays

Driver characteristics for two kinds of map information representation (North-up map and Heading-up map) of in-vehicle navigation system (IVNS) are investigated. Field experiments and laboratory experiments are both conducted. The drivers behavior is investigated by eye movement and subjective evaluation. The results imply that the drivers visiblity is influenced by the cognitive characteristics of the driver, and that the map representation should adapt to the drivers spatial orientation.