Several Researches Of Public Travel Information Service System Based On MapXtreme

Public Travel Information Service System is one of the three transportation Informational demonstration projects of the Ministry of Communications.It provides traffic informations for the public by means of display devices,such as Internet,Call Center,Traffic Radio,Car Terminals,Variable information plate,Warning signs,Big screen and Touch Screen,etc.Over the past few years,we had gain substantial achievements in this field.There were still,however, many deficiencies in dynamic traffic information service. In view of this,the paper mainly studied on the dynamic traffic information service technique by applying the new techniques of IT field,such as WebService,XmlHttp.The paper studied the techniques respectively at first and integrated them into an experimental prototype system finally.The following contents were involved in the paper:(1) System Architecture Design and Traffic Data Organization:The system divided into to two subsystems—the Front Subsystem and the Background Subsystem.The former,which was based on WebGIS platform,used three-tier architecture scheme.The latter used Client-WebService architecture scheme. Besides,the Rough Relational Data Model Theory was used in the database logic structure design.(2) Dynamic Display Technique of the Road Condition:In terms of the function of MapXtreme,the paper designed four schemes.By comparison,schemeⅣwas chozen and was implemented by .net and XmlHttp.(3) Optimal Path Planning Technique:In order to process the massive data,the Dijkstra algorithm was modified. And comprehensively considering the traffic controling,road condition and other dynamic factors, he paper designed the optimal path planning algorithm and realized it.