Zhong Shan City Bureau Of Public Security Of Network Information Retrieval And File Sharing System Design And Implementation

Today, with the rapid development of science and technology, social managementhas undergone a profound revolution. Traditional police work has faced unprecedentedopportunities and challenges. In order to adapt to the social development of informationtechnology, improve the fighting capability of the police, and solid element work, theinformation construction of police department can’t be delayed. A large number of filesare needed to the network transmission on policemen’s daily work. In policemen’s dailywork, a large number of multimedia materials, such as text files, video and so on, aswell as a lot of files need to be delivered in time through the police intranet. In addition,to fight against criminals effectively, the policemen who perform nonlocalreconnaissance missions also need its intranet to exchange intelligence with localdepartment and find the relevant information of the case. Thus it is significant to designa kind of software to achieve effective retrieval, transmission and sharing of internaldocument through the police’s intranet. Not only does it improve the police’s capabilityof maintaining the social and political stability and controlling social security, but it alsofree the police’s resources, reduce police costs, improve efficiency, and establish thepolicemen’s consciousness of information technology applications.This paper firstly analyzed the research status of domestic and foreign informationretrieval and file-sharing systems, and secondly described the characteristics andapplications of P2P. Thirdly the core content of the information retrieval, that is, thecharacteristics and application of Boolean retrieval model, vector space model andprobabilistic retrieval model were introduced in the paper. And then the paperintroduced the key retrieval technical including resource description strategy, selectionalgorithms, merging and sorting algorithms of document resources. The definitions ofsoftware testing and relevant concepts were mentioned finally.Besides, the paper tried to analyze the information retrieval and file-sharing systemof Zhongshan police department’s intranet from the need of the police users in thepublic system, system information managers and system technical support staff. Itfigured out the relevant functional modules according to a distributed resources retrieval and file sharing and made an analysis of the system’s feasibility and safety from theeconomic, technical, operating and social prospects.The design of Zhongshan Police Department’s intranet information retrieval andfile-sharing system mainly included information retrieval function module, file sharingfunction module, online exchange functional modules and admin function module.Meanwhile, the system’s distributed retrieval model, P2P communication model, thedatabase model and detailed database table were designed in the paper.Zhongshan Police Department’s intranet of information retrieval and file-sharingsystem made use of Java EE framework to analyze the framework from the achievementof the presentation layer, business layer and data layer, gave the distributed retrievalmechanism, based on the JXTA P2P communication and online chat code and tested outthe system’s performance and function by the theory of the software testing.