Before he joined NTU, he was a senior researcher at the Agency for Defense Development, Korea. He obtained his PhD in the Department of Computer Science at Texas A&M University. He has published more than 60 papers mainly in the areas of digital libraries, sentiment analysis, hypertext & hypermedia, document engineering, and knowledge organization. He is a member of the Editorial Board of International Journal of Organizational and Collective Intelligence (IJOCI) and Journal of Information Science Theory and Practice (JISTaP).