Hiroko Itoh

On the Design of In-vehicle Advice System

Over the past two decades of years, technological developments have taken place in the field of transportation. Many research and development institutes have been devoted to designing new support systems and in-vehicle information systems to encourage safe, comfortable and convenient maneuvering. This paper deals with the issue of designing in-vehicle advice systems for safe maneuvering, especially by focusing on long-distance commercial vehicles. The authors introduced the characteristics of driving domain. By using the skill-, rule-, and knowledge-based behavior model, the authors analyzed behavior characteristics of drivers, and proposed some basic principles of advice system design to support these three levels of behavior. This proposal will help researchers to identify what advice should be provided and when to be provided. A field study was carried out to support this proposal. The relations of maneuvering characteristics and the drivers status were investigated to discuss about advice on a rule-based behavior. The authors hope that this work will promote further design-oriented discussions on in-vehicle advice system development.

A Method for Quantifying the Risks of Human Error from Experiments with the Ship Bridge Simulator

Why do vessels collide with each other even though the Navigation Officer on Watch (OOW) keeps a lookout? This study aims to discover what causes human error of the OOW. For this purpose we conducted a series of experiments and surveys. This paper reports on results of two experiments and the present state of marine accidents in Japan. The first experiment objective is to find out the correlation between the angle of an approaching target, and error in overlook (cognitive error), and to put forward a method for estimation of Human Error Probability (HEP) from experiments using a ship bridge simulator. The next experiment objective is to find out the correlation between behavior and error in judgment (decision error). The author found that the OOW tends to overlook a target that is approaching from the port side. The other result shows that the notice time is negatively correlated with the amount of time using binoculars. This study concludes that a method for quantifying the risks of human error from experiments is necessary for implementing highly reliable Human Reliability Analysis.

Cognitive Model of Maritime Navigation and its Use for Collision Accident Analysis

Shipping industry plays a vital role in world trade. Especially in Japan, where the land is surrounded by the sea, it carries more than 99 per cent of the volume of trade. Besides international and domestic transport, commercial fishing is one of the main industries in Japan. Major harbors, seaways, and their surrounding areas have high traffic density, and thus the risks of marine accident are not negligible. In this paper, we look into typical cases of collision casualties in middle congested areas outside traffic controlled areas, and discuss how systems can support mariners in collision critical situations. Collision casualties are analyzed from a perspective of encountering types within the traffic environment. According to the types extracted here, cognitive process analysis is then presented. Requirements for each type of collision are also discussed.

Development of a method for marine accident analysis with bridge simulator

The ship operation is system of systems consisted of various systems such as ship management, navigational support, cargo handling and port facility. The marine accidents cause considerable damage to logistics and environment. So, it is effective to ensure the safety of the ship operation. The purpose of this paper is to propose an analytical method for marine accident analysis with the bridge simulator and to confirm the effectiveness of the method. By this analytical method, it has shown to find out the most important factor in navigational watch to avoid marine accident.

Collision Frequency to Offshore Floating Installations based on Analysis of Ship Traffic Flow

A variety of offshore power generation installations have been set in many countries. In the offing of Fukushima, one offshore floating transformer substation and three offshore floating wind turbines have been set as an empirical study to realize the world’s first Wind Farm. However, some effects on ship traffic have been concerned due to installation and collision between ships and installations might occur. In order to maintain and improve navigational safety, it is important to understand collision risks around the installations. In this paper, authors analyzed navigation conditions around the installations by AIS data to consider navigation safety. Also, collision frequencies to the installations were calculated as an index of collision risk based on the analysis of the ship traffic, and consider risks and effects caused by Wind Farm. It is found that there were collision risks because ships navigated near the installations, so that another safety measures may be needed.