https://www.syu.ac.kr/blog/%ed%95%9c%ea%b5%ad%ec%83%9d%eb%aa%85%ea%b3%a0%ed%95%99%ec%97%b0%ea%b5%ac%ec%9b%90-2020-1%ec%b0%a8-%ec%a0%95%ea%b7%9c%ec%a7%81-%eb%b0%8f-%eb%ac%b4%ea%b8%b0%ea%b3%84%ec%95%bd%ec%a7%81-%ec%b1%84%ec%9a%a9/200313_2020-1%ec%b0%a8-%ec%a0%95%ea%b7%9c%ec%a7%81-%eb%b0%8f-%eb%ac%b4%ea%b8%b0%ea%b3%84%ec%95%bd%ec%a7%81-%ec%b1%84%ec%9a%a9%ea%b3%b5%ea%b3%a0%eb%ac%b8-pdf_page_06/