요구사항 작성이 어려울때 파헤치기 https://odaily.tistory.com/entry/%EC%9A%94%EA%B5%AC-%EC%82%AC%ED%95%AD-%EC%9E%91%EC%84%B1%EC%9D%B4-%EC%96%B4%EB%A0%A4%EC%9A%B8%EB%95%8C-%ED%95%98%EB%82%98%EC%94%A9-%ED%8C%8C%ED%97%A4%EC%B9%98%EA%B8%B0-%EA%B2%BD%ED%97%98%EA%B8%B0%EB%B0%98 https://www.elancer.co.kr/blog/view?seq=138