Navigation infom エ ation is necessary for safe and efficient ship handli ． Ship navigators must pick up manually necessary navigation information from a vast amount of them ． In this paper ， we propose automatic retrieval systems for Japanese nautical charts and sailing directions using an engineering work station (EWS) ， and develop its prototype ． These systems are composed of general purpose database ， unified retrieval algorithm and user − friendly interface ． The database of nautica ！charts retrieval systeln is composed nautical charts attribute data of 781 sheets of Japanese nautical charts in Japan adjacent waters ． When the system operator inputs main

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