Improving SMT by model filtering and phrase embedding Chengqing Zong author 2015-dec 3-4 text Proceedings of the 12th International Workshop on Spoken Language Translation: Keynotes Marcello Federico editor Sebastian Stüker editor Jan Niehues editor Da Nang, Vietnam conference publication zong-2015-improving https://aclanthology.org/2015.iwslt-keynotes.1/ 2015-dec 3-4