Operators who engaged in vessel traffic services provide a variety of information to vessels in order to enhance the safety and efficiency of marine traffic. In this study, fixation time of the operator’s eye were analyzed using two eye tracking devices to investigate the real work of VTS operators, who are usually two-person teams at Shimizu Port Radio. The results of analysis with equipment and materials as area of interest in the operation room showed a tendency for the division of work to be determined by the arrangement of equipment. It was confirmed that the time spent looking at the display showing various relevant information of VTS was about half of the time spend on the job, compared with maritime observation and document reading. Also, the operators simultaneously preparing documentation while were communicating via VHF, suggesting that workspace was an important aspect. From the viewpoint of improving the operator's work environment, we also consider importance to design the monitor and equipment layout.

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The goal of this paper is to evaluate the feasibility of using the Standard Marine Communication Phrases offered by the International Maritime Organization (IMO SMCP) in the context of Vessel Traffic Service (VTS) in Japan. To this end, the grammatical rules and vocabulary items used in the SMCP were analyzed to see if these rules, when applied to the SMCP vocabulary, can generate phrases necessary to provide Vessel Traffic Services in Japan referring to the 234 VTS English phrases offered by the Japan Coast Guard and TST Cooperation (Toyo Shingo Tsushinsha). The results indicated that most of these English sentences can be generated by applying a limited set of grammatical rules and function words contained in the SMCP, but that it was necessary to introduce additional vocabulary items.

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The purpose in this study is automatic indication on unstable position data from huge data that is observed information received at Advanced Navigation System (The system is operating at Tokyo University of Marine Science and Technology : TUMSAT). In this study, an unstable AIS position is judged by estimated position that is calculated by AIS position. Unstable AIS information of Shioji-Maru are clear by comparison with observed LAN data at Shioji-Maru. The estimated position with the Karman filter using observed AIS information are obtained at every 1 second. If AIS position is include an inferior position, the estimated position will show the meandered trajectory. An observer can judge that there is the inferior position near the meandered trajectory. And the section of meandered trajectory can be indicated automatically by components after Fourier transform on the change of this moving direction of estimated position. The inferior position defined by the observed value on board and estimated position by AIS were compared, and a Fourier components to assess of inferior information were confirmed.

As a result, an inferior AIS information Shioji-Maru observed by Advanced Navigation System was almost indicated automatically by this method.

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The present study analyzes errors that appear in English uttered by Japanese VTS operators and summarizes them in terms of word order, features related to verbs (tense, voice, and usage), prepositions, and others. These errors seem to have resulted from the lack of formal English training and the urgent need to communicate successfully with non-English speaking mariners who also use somewhat broken English. Based on the errors characteristic of Japanese operators, this paper also proposes an effective learning method for them, showing what should be learned and how, and thus aims at contributing to the safety of navigation in Japanese waters.

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Three events of storm surge which yielded different tidal departures in the head of Mikawa Bay are compared and discussed from the viewpoint of response to the wind forcing. The mechanism of sudden sea level rise is investigated based on the data of wind, sea level and velocity obtained in the period of three different Typhoons which passed near the bay. The magnitude of preceding east wind which gives rise to the sea level in Ise Bay and quick change in wind direction from east to west are key factors to the development of large tidal departure in the head of Mikawa Bay. The propagation of surge waves as a free long wave is confirmed through the velocity profile data and also tested using a 2D simple numerical model.

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During the 2011 off Pacific Coast of Tohoku Earthquake Tsunami, large vessels that could not escape to safe fields in the tsunami-affected areas were helplessly transported by tsunami-induced currents. The positions of a transported vessel in time are analyzed from the data obtained with the Automatic Identification System (AIS) which large vessels are obliged to install by the International Convention for the Safety of Life at Sea. The AIS data on the vessels in the Port of Kashima during the tsunami is utilized for numerical simulation of the tsunami-transported vessels in the port. Further, validation of the numerical simulation with the AIS data demonstrates problems on the numerical simulation of tsunami-transported large vessels.

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Osaka bay is very congested area, since many fishing vessels catch fishes, and many ferries and freighters come and go. In order to prevent maritime accidents, ship operators, operations managers, and pilots desire real-time positional informations about large vessels, small vessels, and fishing gears. The authors have already achieved information dissemination about positional informations of large and small vessels. However, the authors haven't acquired positional informations of fishing gears yet. The ultimate goal of this study is attaining safety and efficient navigation by providing real-time positional informations. In order to approach the goal, this paper presents an auto extraction method, which picks out the starting and finishing points of fishing using positional information of the fishing vessel. These points are very important to predict real-time positions of fishing gears. The authors focused on fishing vessels for Spanish mackerel drift net fishing, and extracted the casting start point and the hauling finish point. From evaluation results, the auto extraction method indicates the different distance less than 500 meters compared with factual starting/fishing points of fishing. This result is sufficient to achieve safety navigation.

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