未定义类型的关系抽取的半监督学习框架研究*
 程显毅1**,朱倩2
 A study of relation extraction of undefined relation type
based on semrsupervised learning framework
 Cheng Xian一Yi1,Zhu Qian2
南京大学学报(自然科学版) . 2012, (4): 466 -474 .