微软satori http://www.bing.com/blogs/site_blogs/b/search/archive/2013/03/21/satorii.aspx
大名鼎鼎的freebase http://www.freebase.com/
Google开源数据抽取、清洗工具 http://openrefine.org/
开源图检索系统 http://www.tinkerpop.com/
强大的问答系统: http://www.wolframalpha.com/input/?i=%E7%8F%A0%E7%A9%86%E6%9C%97%E7%8E%9B%E5%B3%B0%E6%9C%89%E5%A4%9A%E9%AB%98
知识图谱数据结构常用为EAV,即
Entity-AttrName-AttrValue 又名为 Subject-Predicate-Object,或者“三元组(3-tuple)