https://www.syu.ac.kr/blog/%ea%b5%ad%ec%a0%9c-%ea%b8%b0%ec%83%81%ec%a0%84%eb%ac%b8%ec%9d%b8%eb%a0%a5-%ec%96%91%ec%84%b1%ea%b3%bc%ec%a0%95-%ea%b5%90%ec%9c%a1%ec%83%9d-%eb%aa%a8%ec%a7%91/%ed%8f%ac%ec%8a%a4%ed%84%b0-%ea%b5%ad%ec%a0%9c-%ea%b8%b0%ec%83%81%ec%a0%84%eb%ac%b8%ec%9d%b8%eb%a0%a5-%ec%96%91%ec%84%b1%ea%b3%bc%ec%a0%95-%ea%b5%90%ec%9c%a1%ec%83%9d-%eb%aa%a8%ec%a7%91-pdf_page_1/