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Along with the increase of people’s demand on traffic and travel information,travel information service for the public has been the concem focus of communications departments around the world.Many countries and organizations have carried out relevant researchs and practice works.The travle information service system descripted in this paper,is a component of public service web station in Intemet,it geather client’s travel intention informations,such as source,destination,and date,from Web brewer, then gather weather forecasts,train schedules,flight schedule and other information from other information systems by Web Service client invoking,finally return client a synthesis,aid them choose a preferable travel plan.In order to realizate the system,some technowlogies are needed,including Web Services Composition,Information Integration and Intelligent Agents.Web services provides a compute model for distribute applications,which are higher decentralization, independent distribution and suitable for Web environment.And multi Web services which are well organized,can provide complicated services to meet variable Web users’ needs.Agent is a class of compute entity or program that can react with environment and run autonomously to represent designer or user to achieve a series of goal.Multi-Agent System is relaxed and loosely coupled problems solvers,which cooperating with tasks to solve problems,surpasses single problem solver These problem solvers are single Agent. So we can see that Agent and Web services are all self-describing,modularization, reusable in soft module in essential,as a result,the similarity shows that the combination of these two techniques is feasible.And then,Web Services Composition Multi-Agent System offers a new method which can automatically,intelligently,flexibly and self-suitably composite Web services.This paper’s idea of building this system is to extend mulit-agent system,and establish a Multi-Agent System integrated Web Services architecture.This architecture is divided into three layers:Services Coordination Layer,Application Execution Layer,and System Management Layer The major work is involved in the Services Coordination Agent’s processing control,Web Service Invoke Agent’s invoke pattern and invoke result’s cache mechanism.Which empower Multi-Agent System the ability of using Web Service resources and Web Service Composition.By building agent knowledge base based OWL ontology,profiting from the features of Multi-Agent System,this system can provide intelligent value-added services.By adding database server,web server and UDDI to the system,we can expose agent’s function as Web Service to the Internet Heterogeneous Environment,bringing a new level of openness to MAS,and we can alse derive web human-computer interaction interface,enhancing the practicability of MAS. Moreover,by adopting XML coded ACL communition language,XML database technology,the data representing among Agent,Web Service and Servlet is unified. When user use this service system,what he needs to do is simply select in menu or type in address,this system can correctly identify the user intenlion,and give back suitable weather forecasts,train schedules,flight schedule and other informations. Compare with other systems developed by traditional methods,advantages is obviously. At last,we validate this system architure by the design and implement of a personal travel information service web system.But as a preliminary version,the system is short in many areas,including the dynamic Web services discovery and composition,the travel planning compute involving transit,user reference agent,and so on.Some further works are considered to perfect the system to improve intelligence,and other characteristics, those works are adapting Semantic Web services technowledge,expansding Agent knowledge base and buiding of ontology reasoning rules.
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