Topic distillation using hierarchy concept tree. - Ikkyu Choi; Minkoo Kim (SIGIR, 2003)

Refining term weights of documents using term dependencies. - Hee-Soo Kim; Ikkyu Choi; Minkoo Kim (SIGIR, 2004)

Semi-automatic construction of domain ontology for agent reasoning. - Ikkyu Choi; Seungmin Rho; Minkoo Kim (Pers. Ubiquitous Comput., 2013)

Off-Topic Spoken Response Detection Using Siamese Convolutional Neural Networks. - Chong Min Lee; Su-Youn Yoon; Xihao Wang; Matthew Mulholland; Ikkyu Choi; Keelan Evanini (INTERSPEECH, 2017)

Off-Topic Spoken Response Detection with Word Embeddings. - Su-Youn Yoon; Chong Min Lee; Ikkyu Choi; Xinhao Wang; Matthew Mulholland; Keelan Evanini (INTERSPEECH, 2017)

Word-Embedding based Content Features for Automated Oral Proficiency Scoring. - Su-Youn Yoon; Anastassia Loukina; Chong Min Lee; Matthew Mulholland; Xinhao Wang; Ikkyu Choi (SemDeep@COLING, 2018)