Affiliation: | (1) Department of Physics, Dongguk University, 100-715 Seoul, Korea;(2) Department of Physics, Kun-Kuk University, 133-701 Seoul, Korea;(3) Agency for Defence Development, 4-5-1, Daejeon, 305-600, Korea;(4) Department of Physics, Kwangwoon University, 139-701 Seoul, Korea |