https://blog.gongquiz.com/2021/09/13/%ec%9d%8c%ed%99%98%ea%b2%bd%ec%97%90%ec%84%9c-%ec%a0%95%ec%9d%98%ed%95%98%eb%8a%94-%ec%9d%8c%ec%95%95sound-pressure%ec%9d%98-%eb%8b%a8%ec%9c%84%eb%a1%9c-%ec%98%b3%ec%9d%80-%ea%b2%83%ec%9d%80/