| 2019 | Chosun Univ., Handong Univ., Ajou Univ.. |
| 2018 | Kyunghee Univ., KAIST, Chungang Univ. |
| 2016 | Univ. of Bonn (May 6) |
| 2015 | ○ Brown Univ. ○ Uinv. of Pennsylvania ○ Univ. of Pittsburgh ○ Penn State Univ. (colloquium) ○ Carnegie Mellon Uinv. ○ Univ. of Wisconsin, Madsin ○ Georgia Tech ○ Univ. of Minnesota |
| 2014 | ○ (Seminar) Seoul National University, Korea, Oct. 17 |
| 2013 | ○ (Colloquium) Sogang University, Korea, Oct. 30 ○ (PDE seminar) Yonsei University, Korea, Nov. 1 ○ Chinese Univ. of Hong Kong, April 22-26 |
| 2011 | ○ KAIST, Korea |
| 2010 | ○ (Colloquium) Seoul National University, Korea ○ Sogang University |
| 2009 | ○ (Colloqioum ) “Introdunction to Mathematical biology” at Ajou University, Dec. 4, 2009 |
| 2008 | ○ Chonbuk National University, Korea ○ (Colloquium) SungKyunKwan Univ., Korea ○ KAIST, Korea ○ CSIC (CONSEJO SUPERIOR DEINVESTIGACIONES CIENTIFICAS), Madrid, Spain |
| 2007 | ○ Brown University, USA ○ Max-Planck-Institute for gravitaional physics, Potsdam, Germnay, ○ Trinity College Dublin, Ireland ○ Kaist, Korea ○ (Colloquium) KIAS, Koreea ○ Univ. of Compultense, Madrid, Spain ○ Sungkyunkwan Univ., Korea ○ (Colloquium) Korea Univ., Korea ○ (Colloquium) Yonsei Univ., Korea ○ Seoul National Univ., Korea |
| 2006 | ○ Brown University, USA ○ NC state University, USA ○ Univ. of Dundee, Scotland ○ Hanyang Univ., Korea ○ Sungkyunkwan Univ., Korea ○ Soongsil Univ., Korea |
| 2005 | ○ Texas A&M, USA ○ Simon Fraser Univ., Canada ○ Syracuse Univ., USA ○ UC Riverside, USA ○ Trinity College Dublin, Ireland ○ Max-Planck-Institute in Leipzig, Germany ○ Bayreuth Univ., Germany |
| 2004 | ○ Ajou University, Korea, ○ Korea University, Korea, ○ Postech, Korea, ○ Seoul National University, Korea, ○ Brown University, USA ○ Max-Planck-Institute in Leipzig, Germany ○ University of Maryland at College Park, USA |
| 2003 | ○ University of Wisconsin at Madison, USA ○ Brown University, USA ○ Duke University, USA ○ Yonsei University, Korea, ○ Postech, Korea ○ Max-Planck-Institute in Leipzig, Germany ○ Universite Paul Sabatier, France, |
| 2002 | ○ Max-Planck-Institute in Leipzig, Germany ○ Yonsei University, Korea ○ Postech, Korea ○ Seoul National University, Korea ○ University of Vienna, Austria |
| 2001 | ○ Brown University, USA |