5、roundofthesystem11.2Practicalsignificance21.3Thepurposeofthisthesis41.4The main technic of in this paper51.5Theframeandstructureofthisthesis7Chapter2Theanalysesonthesystemrequirements82.1Thegeneraldescription82.1.1Theservicemodelofthesystem82.1.2Theserviceprocessofthesystem92.1.3Thegeneralrequ