- Topology and related algebra, geometry, analysis and applications

2000-2002 Instructor/Research Assistant Professor, KAIST
2002-2003 Visiting Scholar, Visiting Assistant Professor, Indiana University
2003-2007 Assistant Professor, Information and Communications University (currently KAIST)
2007-current Assistant Professor/Associate Professor/Professor, POSTECH
2009-2021 Affliate Professor, KIAS
2011-2014 K. W. Kwun Chair Professor, POSTECH
2013-2014 Visiting Professor, Indiana University
2014-2017 Yeonsan Chair Professor, POSTECH
2017-2019 Mueunjae Chair Professor, POSTECH
2017-2018 Visiting Scientist, Max Planck Insttitute for Mathematics

2009 Research Paper Award, Korean Mathematical Society
2011 Scientist of the Month, Ministry of Education, Science and Technology
2022 PKC Test of Time Award, International Association for Cryptologic Research