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Vessel Traffic Data

其他書名	Extraction Methodology
出版	Defense Technical Information Center, 1976
URL	http://books.google.com.hk/books?id=k7bSGwAACAAJ&hl=&source=gbs_api

註釋This report presents a description of the methods used to extract vessel traffic data during a 20-month project encompassing seven U.S. port areas. The data was obtained from films of radar PPI's and tapes of communications activity on Channels 13 and 16 of the VHF/FM Maritime Mobile Band. Data analysis obtained the following: Vessel Density; Vessel Route Identification; Vessel Speed; Close Encounter; Message Activity, Channel Utilization, and Channel Efficiency. Discussion of error sources and data display are included. (Author).