Research On Key Technology Of PDA-based Mooring Monitoring System

With large ships and port shoreline resource depletion, wharf construction has become a necessity. At present, China has been built one hundred or more large wharf berths, including Qinhuangdao, Dalian, Huangdao, Zhanjiang, Beilun, sunshine, Meizhou Bay, Zhoushan, Huizhou, Maoming Port and so on,which are used for international transportation of oil, liquefied natural gas (LNG berths) and chemical products. Presumably,the demand for such berths will grow rapidly in next20years.For large wharf, offshore power portfolio environment (waves, tide, wind) affects on the mooring vessels directly, then mooring ship will move and dynamic response will occur, which lead to a rapid increase in the mooring line tension. With strong randomness of sea state and weather conditions controlled by the local waters geography and topography,there are broken cable and other accidents in the wharf,which cause great economic losses, reduce the credibility of the port security and affect their sustainable development. Preventing the accidents of wharf cable breakage and establishing a reliable mooring monitoring system, become the industry one of the key problems to be solved.This article details the design and come true of The Pier Moored Vessels Monitoring System based on the PDA.First of all,specially addressed the background knowledge of the PDA,including development condition,the type of operating system as well as wireless communication technology,etc.Selecting handheld devices which based on Android Operating System as its Mobile Client Tools,and we have made a detailed elaborate about Android development technology,architecture as well as browser.Secondly,formulating overall design program of the system,according to the demand to divide function module unit,and to select development model.Select a specific development tools and runtime environment based on the development model.The system mainly consists of C/S Mode Local Monitoring Subsystem and B/S Mode Remote Monitoring Subsystem.Mobile Handheld Device End and Remote Monitoring Subsystem communicating with each other.In the aspect of database design, establish the data model of E-R.Finally,according to Remote Monitoring Subsystem,Local Monitoring Subsystem and Mobile Client to give a specific implementation process to functional unit,and analysis and research which relates to key technologies including Web Service application,Server "Push" Technology and Dom Parsing.