The Design And Implementation Of The Storage And Display System For Real-time Navigation Data Stream

With the vigorous development of maritime transportation, the vital role of ships,which are carriers of maritime transportation,is becoming increasingly unshakeable. The cruelty rescue result of the marine perils warns us that it is time to promote the position of ship navigation in the marine technology,and we should improve our offshore power urgently. The level of marine technology is the main part of the marine power. In order to develop our marine technologies, government and the society should devote much wealth and energy.The processing of data-stream in ship navigation which is one of the basic technologies plays a fundamental role in the field of ship automation and information construction. The information data of navigation is produced by navigation devices, and then stored and transmitted in a way of streams in the local network of a ship. Because of the large number of navigation devices in each ship, the different equality and performance of the devices and the severe sea condition, the state of data in ship network is very complicated, which is a great challenge in designing and realizing the storing and showing system of the real-time data-streams in ship navigation network.In this case, we analyze the data and network of the ship navigation and sum the features up, and study the difficult points and key problems of designing and realizing the storing and showing system of the data-stream in ship navigation network. Some data structures are created to solve the serious problem of network fluctuation. Two different ways, the in-memory database of SQLite system and the memory buffer, are adopted to realize the subsystem of buffering, which increases the stability and flexibility of the system dramatically. We also conduct some tests to prove the feasibility of our way.Considering the large number of navigation data in the system, the mechanism of dividing the database and table is created, which is programmed in the open source database system, PostgreSQL, to store the information data. We compare the divided database and table storage mechanism with the integrating mechanism to find the advantages and disadvantages of the two mechanisms. The description of the usage of the two mechanisms is instructive and meaningful, which is one of the meanings of this master dissertation in some degree.There are two different forms of showing the navigation packet data in the article. The former shows the navigation data through the model of a table in detail, while the latter uses the way of drawing with the fitted curves based on the fragmented Bezier Curve. The results of the test says that it can show both the details and the changing trend of the data with the two methods, which can even tell some of the fault data produced by the failed navigation devices.