Fuel cells are one of the future technologies for marine energy sources. A fuel cell combines hydrogen and oxygen to produce electricity, with water and heat as its by-product. Since the conversion of the fuel to energy takes place via an electrochemical process, the process is clean, quiet and highly efficient.This paper presents the types and characteristics of fuel cells, the status of marine use, and the outline of safety requirements which apply to fuel cell power generation systems.

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IMO (International Maritime Organization) has regulated the discharge of oil from ships due to the large scale incidents at sea. OPRC-HNS Protocol (Protocol on Preparedness, Response and Co-operation to Pollution Incidents by Hazardous and Noxious Substances) became effective in June 2007. The potential danger of pollution from sunken wrecks has been discussed during the major international oil spill conference. The National Maritime Research Institute has planned to develop a hazard map of stranded and sunken ships in order to use technology to prevent oil discharges at sea. For this purpose, stranded and sunken ships around the Sea of Japan have been investigated. Data of 3,503 grounded and sunken ships have been obtained in the year between 1900 and 2004.The sunken ship data are plotted on the map. Using 3 factors which are the time of oil discharge, the degree of volume of discharged oil, and the distance between sunken point and coast, the potential danger of sunken ships to the environment has been discussed.

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With adequate and detailed information, a large plant operator can generally maintain a plant's good working condition. A ship engineer has the same work as a plant operator except that self-sufficiency at sea is a requirement for ship engineers. On the basis of the cognitive process of human activities, Rasmussen proposed three different modes which are the knowledge-based mode, the rule-based mode, and the skill-based mode. One important but complex feature is to understand how to do the plant operator shift between each mode. In this paper, we focus on the proficiency training of ship engineers. Some experiments were carried out on the training ship of the National Institute for Sea Training, Japan. Firstly, some experts (licensed marine engineers) were asked to operate the valve of a centrifugal pump. Their eye motions and the operating conditions were captured on videotape. Simultaneously, the experts' comments and explanations regarding the main points to be aware of were also recorded. Secondly, we divided the cadets into two groups. One group watched the video and listened to a typical explanation of handling the valve of a centrifugal pump. On the other hand, the other group watched the video and listened to the explanations of the experts in addition to the usual explanation. We compared the results of the two groups and found out some advantages of the second method in which the detailed explanations of the experts were added. Furthermore, the effect of role-playing on training between the two groups playing the role of "Instructor" and "Operator" was also compared.

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A basic study on the development of sliding materials which can be used in seawater is made in this paper. As well known, stainless steel and titanium alloy are both fine anti-corrosive materials in seawater, but these are easily worn as resulting from corrosive type of wear in seawater. In order to overcome the disadvantage silicon (Si) particles were embedded into the surface layers of them, by applying the rubbing treatment process which was developed by the authors. The wear tests were done in artificial seawater by using the reciprocating wear apparatus. The results show that the coefficient of frictions are not so improved, but wear resistant properties are improved, especially for Si treated stainless steel mated by the same substrate material. Based on the results the wear mechanism of the developed materials is discussed.

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