*Chia-hung CHEN¹, Charles LIN¹, Loren CHANG², J. D. HUBA³, Akinori SAITO⁴, Jann-yenq LIU² (1.Department of Earth Science, National Cheng Kung University, Tainan, Taiwan, 2.Institute of Space Science, National Central University, Chung-Li, Taiwan, 3.Plasma Physics Division, Naval Research Laboratory, Washington, D. C., USA, 4.Department of Geophysics, Kyoto University, Kyoto, Japan)