1. Department of Astronomy, Space Science and Geology, Chungnam National University, Daejeon, South Korea
2. Department of Geological Sciences, Chungnam National University, Daejeon, South Korea
3. Department of Geography and Anthropology, Louisiana State University, Baton Rouge, LA, USA
4. Air Quality Research Department, Chungcheongnam-do Institute of Health and Environment Research, Hongseong, South Korea