https://blog.gongquiz.com/2023/11/01/%eb%8b%a4%ec%9d%8c-%ed%9a%8c%eb%a1%9c%ec%9d%98-%ec%a3%bc%ed%8c%8c%ec%88%98-%ec%a0%84%eb%8b%ac%ed%95%a8%ec%88%98transfer-function-%eb%8a%94-9%ea%b8%89-%ea%b5%ad%ea%b0%80%ec%a7%81-%ea%b3%b5/