著者

古莊 雅生 甲斐 繁利 橋本 進

出版者

公益社団法人 日本航海学会

雑誌

日本航海学会論文集 (ISSN:03887405)

巻号頁・発行日

vol.85, pp.51-62, 1991-09-25 (Released:2017-01-15)

被引用文献数

5 6

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Nowadays, the speed of ships has increased, and high speed vessels are now being operated, such as the JETFOIL and HOUVER CRAFT which travel at the speed between 30 and 50 knots. We have taken the measurement of the eye-movement of the pilot on board the super speed vessel, JETFOIL, by using an eye-pointer. We have analized the data with the pilot's head fixed forward, and the result is as follows. (1) When the vessel is running on hull-borne in a harbor, the eyes of the pilot move broadly breadthwise. (2) When the vessel is foil-borne on the open sea, the eyes of the pilot move lengthwise in a narrow area.

著者

高 欣佳 牧野 秀成 古莊 雅生

出版者

公益社団法人 土木学会

雑誌

土木学会論文集B3(海洋開発)

巻号頁・発行日

vol.70, no.2, pp.I_948-I_953, 2014

被引用文献数

1

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経済発展と共に物流のほとんどを担う海上交通において,船舶数も急増しそれらが航行する海域では輻輳するため海難事故が多発している.船舶の安全かつ効率的な運航を行うためには,船舶の航行実態及び航行海域の輻輳状況の詳細を把握する必要がある. 本研究では,特に,船舶が入港する際に港外で入港の順番を待つ所謂"沖待ち"行動に着目した. この船舶の沖待ち行動は航行船舶にも影響を及ぼすために把握する必要があるが,これまでは各船舶の沖待ち自体のデータを入手することは難しく,沖待ちの実態を把握することが困難であった.しかし,本研究では,近年,船舶に搭載が義務付けられた船舶自動識別装置から送信されるデータを収集し解析することで,沖待ち船舶を抽出しその実情を把握した.更にそれらが航行船舶に与える影響を把握するために,海域における船舶密度を基に船舶の輻輳状況を解析した.本稿では,これらの結果について報告する.

著者

古莊 雅生

出版者

公益社団法人 日本航海学会

雑誌

日本航海学会論文集 (ISSN:03887405)

巻号頁・発行日

vol.93, pp.35-42, 1995

参考文献数

13

被引用文献数

3 1

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The visual perception of the targets at sea is the most important factor for safety and for a good lookout in preventing maritime traffic accidents. This study shows the conditions for being able to perceive the visible horizon between the sky and sea surface and this. Author shows the visual and nautical conditions thereof ; they are as follows; 1. The conditions of visual perception of the line of division between the sky and sea surface is that the luminance difference of the sky (about 2 degrees over horizon) and sea surface (about 2 degrees under horizon) is more than the luminance difference threshold. 2. When nobody can perceive the above line of division (horizon), the visual and nautical environment is indicated as follows; (1) The luminance of the sky (about 2 degrees over horizon) is 0.3cd/m^2. (2) The luminance of the sea surface (about 2 degrees under horizon) is 0.03cd/m^2. (3) The difference luminance threshold is 0.27cd/m^2. But in the case of 0 degree which is a relative direction towards the direction of the sun. 3. A sun altitude with above the mentioned condition is -6〜-9 degrees (1/3〜1/2 duration of astronomical twilight), which is connected with the relative direction towards the direction of the sun. 4. The luminance of the sky and sea surface and the illuminance of the sky have gone up and down with the sun's altitude, and they change rapidly and widely with the case of the time period from sunset and sunrise to -9 degrees of the sun's altitude. 5. When under way the time period from sunset and sunrise to -9 degrees of the sun's altitude is needed to keep a special caution for a good lookout and the safety of the ship.