一个命名实体识别工具，是Mallet开放源码项目的一部分，可用于识别文本中的人名、地名等信息-a named entity recognition tools, Mallet OSS part of the project, Text can be used to identify the names, places and other information

对北大语料进行地名前后次的抽取，通过设置一个阈值，来控制选择。-Names of the Beijing University corpus to carry out before and after the meeting of the extraction, by setting a threshold, to control the choice.