2006 - 2023 Pukyong National University, Busan, South Korea 2010 - 2012 Kyonggi University, Suwon, South Korea 2009 - 2010 University of California, Davis, California, United States 1999 - 2006 Pusan National University, Busan, South Korea 2005 Gyeonggi Research Institute, Suwon, South Korea 2004 Kyonggi Research Institute, Suwon, South Korea