Information Retrieval Technology 4th Asia Infomation Retrieval Symposium, AIRS 2008, Harbin, China, January 15-18, 2008 Revised Selected Papers - Li, Hang; Liu, Ting; Ma, Wei-Ying; Sakai, Tetsuya; Wong, Kam-Fai; Zhou, Guodong (Springer Berlin Heidelberg, 2008)