Z. Liu, T. Wang, N. Pinkwart, S. Liu, and L. Kang. An Emotion Oriented Topic Modeling Approach to Discover What Students are Concerned about in Course Forums. Proceedings of the 2018 IEEE 18th International Conference on Advanced Learning Technologies (ICALT), pages 170-172, 2018. Z. Liu, L. Kang, M. Domanska, S. Liu, J. Sun, and C. Fang. Social Network Characteristics of Learners in a Course Forum and Their Relationship to Learning Outcomes. Proceedings of the 10th International Conference on Computer Supported Education, Volume 2, pages 15-21, 2018.