1 Geophysical Geodesy lab Seoul National University,#407 BLDG. 13, KWANAK-RO 599, KWANAK-GU, SEOUL, KOREA TEL : +82-2-880-4070 Prof. Ki-Weon Seo Seoul National University,#406 BLDG. 13, KWANAK-RO 599, KWANAK-GU, SEOUL, KOREA TEL : +82-2-880-7779