| 1989. 1. 13. - 1989. 1. 14. | Program Chairman of the 1st Workshop of Image Processing and Understanding |
| 1989. 3. 1. | Organization Chairman of '89 Spring Conf. of the Society of Artificial Intelligence Research |
| 1990 | Program Chair, First Korea Japan Workshop on Computer Vision |
| 1990. 12. 1. | Session Chairman of '90 International Conf. on Computer Vision |
| 1990. 11. 10. | Chief Chairman of the AI section of '90 Fall Conf. of Korea Information Science Society |
| 1991 - 1993 | Chairman of the Society of Artificial Intelligence Research in Korea Information Science Society |
| 1991. 10. 1. - 1991. 11.30. | Member of Korea Information Science Society |
| 1991. 10. 1. | Program Chairman of First Korea-Japan Joint Conf. on Computer Vision |
| 1992 - 1996 | Governing Board Member, International Association for Pattern Recognition (IAPR) |
| 1992. 9. 1. | Director of International Association for Pattern Recognition(IAPR) |
| 1992. 9. 15. - 1992. 9. 18. | Local Arrangement Chairman of Second Pacific Rim International Conf. on Artificial Intelligence |
| 1992, 1993, 1995 | Program Committee Member Asian Conf. on Computer Vision |
| 1992, 1995, 1998, 2002 - 2006 | program committee member, PRICAI(Pacific Rim Intl Conf. on Artifiical Intelligence) |
| 1993. 1. 1. | Program Committee Member of First Pacific Rim International Conf. on Computer Graphics |
| 1993. 5. 11. - 1993. 5. 13. | Program Committee Member of 4th International Conf. on Computer Vision |
| 1993. 11. 23. -1993. 11. 25. | Program Committee Member of First Asian Conf. on Computer Vision |
| 1993. 12. 31. | Chairman of the field of AI in Info Science '93 |
| 1995. 2. 3. - 1995. 2. 4. | General Chairman of 7th Workshop on Image Processing and Understanding |
| 1995. 11. 5. - 1995. 11. 8. | Advisory Committee Member of Second Asian Conf. on Computer Vision |
| 1995. 11. 1. | Program Committee Member of Second Pacific International Conf. on Computer Graphics |
| 1995 - Now | Korean Member of gate io |
| 1996 - Now | Korean Member of FIPA (Foundation for Intelligent Physical Agent) |
| 1996, 1997 | Program Committee Member, Pacific Intl conf. on Computer Graphics |
| 1997. 9. | Invited Speaker of International Symposium on Robotics Research |
| 1998. 1. 14. - 1998. 1. 15. | Program Chairman of International Workshop on Advanced Image Technology (IWAIT) |
| 1998, 2003 | Intl Advisory Committee Member, International Conf. on Robotics, Automation, Computer Vision |
| 1998.11 - Now | Board member of Korea Information Science Society |
| 2000 | Program Committee Member, Intl Conf. on Neural Information Processing(ICONIP) |
| 2002 | Program Chair, 8th Intl Conf. on Virtual Systems and Multimedia (VSMM 2002) |
| 2003 - Now | Board Member, Korea Brain Society |
| 2004 - Now | Board Member, Korea Multimedia Society |
| 2004 | General Chair. 14th Intl Conf. on Artificial Reality and Telexistence |
| 2005 | Program Chair, Intl Workshop on Ubiquitous Experience Media |
| 2006 | Guest Editor, Special Issue on Artificial Reality and Telexistence, IEICE Trans. on Information and Systems (Japan) |
| 2008 | Program Chair, Intl Conf. on Entertainment Computing (ICEC2008) |
| 2008 | Program Chair, ASIAGRAPH Tokyo 2008 |
| 2008 | General Chair, International Symposium for Arts and Technology (ISAT2008) |
| 2009 | General Chair, 21C TransMedia Innovation Symposium (21CTIS 2009) |
| 2009 | General Chair, International Symposium for Arts and Contents (ISAC2009) |
| 2010 | General Chair, Intl Conf. on Entertainment Computing (ICEC 2010) |
| 2010 | General Chair, 16th Virtual Systems and Multimedia (VSMM 2010) |
| 2010 | General Chair, Virtual Reality Continuum and Its Applications (VRCAI 2010) |
| 2011 | Honorary General Chair, Institute of Electrical and Electronics Engineers Virtual Reality (IEEE VR 2011) |
| 2011 | General Chair, International Symposium on VR Inovation (ISVRI 2015) |
| 2013 | Scientific Chair, International Congress on Digital Heritage 2013 |
| 2014 | Program Chair, 20th Virtual Systems and Multimedia (VSMM 2014) |
| 2014 | General Chair, Virtual Reality Continuum and Its Applications (VRCAI 2014) |
| 2015 | Program Chair, Virtual Reality Continuum and Its Applications (VRCAI 2015) |
