节点文献
基于MapXtreme构建公众出行交通信息服务系统若干技术研究
Several Researches of Public Travel Information Service System Based on MapXtreme
【作者】 袁超;
【导师】 刘小勇;
【作者基本信息】 新疆农业大学 , 载运工具运用工程, 2009, 硕士
【摘要】 公众出行交通信息服务系统是交通部交通信息化示范工程的三个组成部分之一。它依托各种交通信息资源,通过互联网、呼叫中心、交通广播、车载终端、可变情报板、警示标志以及公共场所内的大屏幕和触摸屏等显示装置,为公众提供较为完善的出行信息服务。近几年,我国对于公众出行交通信息服务系统的建设已取得了一些成果,但在动态交通信息服务方面仍显不足。鉴于此,本文结合当前计算机领域的一些最新技术(如WebService、XmlHttp等),并综合考虑交通管制、实时路况等动态因素,研究了动态交通信息服务方面的技术。论文采用“先分后总”的研究方法,即先分别研究各关键技术,然后对这些技术进行整合,开发一个实验原型系统,并以该系统为平台对所研究的技术进行验证。论文主要作了如下研究:(1)系统构架方案和路网数据组织方法研究。将系统分为前台和后台两个子系统:前台基于WebGIS平台,采用三层架构设计方案;后台采用Client-WebService模式的C/S架构方案。研究路网数据组织方法,引入了粗关系数据模型的概念,设计了路网的空间数据库和属性数据库逻辑结构。(2)实时路况动态显示技术研究。结合MapXtreme的功能,设计了四种方案和算法。最后选定方案四,并借助.net平台和XmlHttp技术对算法进行实现。(3)最优路径规划技术研究。修改Dijkstra算法,以使其实用化。综合考虑交通管制、实时路况等动态因素,设计既能满足静态最优路径规划,又能满足动态最优路径规划的算法,并对算法进行实现。
【Abstract】 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.
【Key words】 Public Travel Information Service System; MapXtreme; WebGIS; WebService; dynamic display technique; Optimal path planning;