Editor, Korean Institute of Information Scientists and Engineers Jan. 2007. – present Auditor, The Korean Association of Computer Education Mar. 2018. – Feb. 2020. Vice President, Korea Information Processing Society Jan. 2015. – Dec. 2020. Vice President, Korean Institute of Information Technology Jan. 2014. – Dec. 2016. Vice President, The Korean Association of Computer Education Mar. 2014. – Feb. 2018. Director, Korea Information Processing Society Feb. 2010. – Dec. 2014. Vice President, The Korean Association of Computer Educationy Mar. 2006. – Feb. 2010. Director, The Korean Association of Computer Education Mar. 2002. – Feb. 2005. International Conference on Ubiquitous Information Technologies and Applications, International Advisory Committee 2014, 2015, 2016, 2018, 2019 International Conference on Future Computer and Communication, Technical Committee 2016 International Conference on Advanced Information Networking and Applications, Program Vice Chair 2015 International Conference on Multimedia and Ubiquitous Engineering, Program Committee 2015 International Conference on Grid and Pervasive Computing, Session Chair 2012