The Research And Implementation Of High-performance AIS Data Access System

Ship Automatic Identification System--AIS is a new digital navigation system integrated with network technology, modern communication technology, computer technology and electronic information display technology. The system is composed of shore-based facilities and ship equipment and has broad applications in the vessel collision avoidance and maritime management.With the rapid development of AIS system and the rapid increase of the amount of data, data disaster problems are given more and more attention. In China, for example, the amount of message received by base station one year in the northern sea area is more than500GB. If these data can be certain filtered and integrated, the data resources will be very valuable and can reduce data disaster. In this background, this paper adopts high-performance AIS data access system to study the ocean vessel density distribution and do research on the data access technology.This paper is based on Oracle Database to design high-performance AIS data access system and the system is mainly composed of three parts:The first part is data acquisition and processing unit realized by Qt programming in Ubuntu11.10. It is responsible for filtering, classifying and uploading the collected data to the database, and mainly uses the data decoding technology, the thread pool parallel processing technology, bulk storage database technology and so on. The second part is data accessing unit based on Oracle1lgR2in Redhat6.2. It designs the database combining with the characteristics of data accessing, giving full consideration of the Oracle Database and the Linux operating system performance, at the same time the key is to design the table space, table, the partition and so on. The third part is data applying unit realized by Qt programming in Ubuntu11.10. It is responsible for directly showing the number of per area ships, and adopts the heat map technology to improve the visual display.On the basis of the above design of the system, this paper also researches systematic optimization design. It optimizes the system from two aspects of storing data and extracting data, at the same time according to actual test data of the system, it constantly changes optimization scheme and accesses to the relevant information to find theoretical support, until the performance of the system achieves relatively optimal state.The research content of this paper is the part of the national support plan project of the institute "New high-availability system AIS ship autonomous navigation system (2012BAH36B01)".