THE KEY TECHNIQUE AND APPLICATION OF CONSTRUCTING NOTICE TO MARINERS DATABASE
G.H. Liu, R.C. Peng, W.J. Gao, Y. Chen, L.X. Guo
Department of Hydrography and Cartography, Dalian Naval Academy, Dalian, China
Notice to Mariners is a kind of periodic publication which issues the information about navigation security and nautical book’s correction data. Mariners often correct paper chart or electronic chart according to it. Along with the fast development and wide application of computer and database, many countries have already constructed Notice to Mariners database for their issued charts, and there are also some countries constructed the update system based on Notice to Mariners database. But the research in this field is poor in china, and various correction data is still edited by the method of manually drawing graphics in the paper chart. Apparently, this method can not use the database technique to edit, store and manage the correction data, which results in the problems during the process of editing Notice to Mariners now, such as low efficiency and inutility work. On base of analyzing the production flow of Notice to Mariners and the defect in editing Notice to Mariners, this paper carried out the technique of editing the correction data by the method of correcting digital chart data, then researched on the technique of extracting the updating data from digital chart data which had been corrected and storing updating data in the Notice to Mariners database, and lastly researched on the technique of automatically creating the Notice to Mariners by the method of renewing information. The Notice to Mariners database which contains the full updating information can also be used as the source data to update other chart data.