https://chiup.edume.co.kr/course/ncs-%ec%a7%81%ec%97%85%ea%b8%b0%ec%b4%88%eb%8a%a5%eb%a0%a5%ed%8f%89%ea%b0%80%ec%a7%81%eb%ac%b4%ec%88%98%ed%96%89%eb%8a%a5%eb%a0%a5%ed%8f%89%ea%b0%80%ed%86%b5%ed%95%a9%ec%99%84%ec%84%b1%ed%8e%b8/ 2019-01-03T13:54:12+00:00 always 0.6