2008–present | Institut Telecom, Telecom SudParis, associate professor, Evry, France |
2007–2008 | NIST, guest researcher, Gaithersburg, USA |
2007–present | ETRI, invited researching staff, Daejeon, KOREA |
2007–2009 | KAIST (former, ICU), research professor, Daejeon, KOREA |
2005-2007 | KTI, senior engineer, Seoul, KOREA |
2002–2003 | CUBIN, The University of Melbourne, visiting researcher Melbourne, Australia |
2001–2002 | ETRI, contract researcher, Daejeon, KOREA |
1999–2000 | KT, internship researcher, Daejeon, KOREA |