Network Public Opinion Research And Implementation Of Key Technologies,

With the rapid development of computer technology and communication technology, the Internet has become indispensable part of people's lives. According to the ITU statistics, up to December 2010, the total number of global Internet users was more than 2 billion. And the number of Chinese Internet users was more than 390 million. Internet has been recognized as "the 4th media" after newspaper, radio, and TV. The public right to know, to express, to participate, and to supervise has been implemented on the Internet. Internet users commented on people's livelihood, government management, anti-corruption, social morality and hot issue enthusiastically, which has formed a kind of strong pressure of public opinion. The influence of Internet has exceeded the traditional media, and has become the most important carrier of social public opinion.In the rapid development of public opinion on the Internet, analysising and monitoring public opinion of Internet has become increasingly important. Internet with open and relatively free of loose degree, allows people to speak out of control and restriction of the system of social rights. People can open up broad expression of personal opinions, positions, emotions, and expression of public opinion is clearer. The virtual Internet poses a significant security risk, speaker identity conceals, and lack of rules limits and effective oversight. So Internet can easily become the space for some Internet users to vent negative emotions. Our country has long been in isolation, which is vulnerable to external ideological culture. And our country is in the social transition, so the contradictions exist. And a few social managers are used to avoid or congestion public opinion. Therefore, public opinion analysis system is needed for network monitoring, timely preventing social harm caused by misleading opinion, grasping and safeguarding right opinion forward oriented, for constructing harmonious society public opinion.In this thesis, requirements of public opinion analysis system were analysised and system was designed. Web text category, sentiment classification, and other key technologies were implemented. Advanced expressed in this thesis: 1) For the current limitations of existing crawler techniques a data collection method based on crawling policy and filtering policy was put up, which could filter a lot of useless information. An update strategy of a local website database was developed for public opinion analysis system, to ensure that web pages of the local website database were fresh.2) Web page classification techniques based on Naive Bayes were studied. A rough set weighted Bayesian classification method was improved, and the method was applied to public opinion analysis system.3) The existing text orientation analysis techniques based on machine learning and semantic information were discussed. An improved machine learning method based on semantic information was put up. And the method was applied to the public opinion analysis system.