https://www.syu.ac.kr/rnd/2020%eb%85%84%eb%8f%84-%ec%bd%94%eb%a1%9c%eb%82%9819-%ec%b9%98%eb%a3%8c%ec%a0%9c%c2%b7%eb%b0%b1%ec%8b%a0-%ea%b0%9c%eb%b0%9c-%ec%8b%a0%ea%b7%9c%ec%a7%80%ec%9b%90-%eb%8c%80%ec%83%81%ea%b3%bc%ec%a0%9c/