Utterance Segmentation Using Combined Approach Based on Bi-directional N-gram and Maximum Entropy Ding Liu author Chengqing Zong author 2003-07 text Proceedings of the Second SIGHAN Workshop on Chinese Language Processing Association for Computational Linguistics Sapporo, Japan conference publication liu-zong-2003-utterance 10.3115/1119250.1119253 https://aclanthology.org/W03-1703/ 2003-07 16 23