The words 이상 and 이하 can follow a number to mean "more than" or "less than":
However, it's not always clear if the number itself is included: does the above mean "more than 3 years" or "3 years or more"?
The dictionary isn't so helpful:
이상: 1. 수량이 기준을 포함하면서 그 위인 경우
2. 정도가 기준보다 높음
One seems to suggest the amount is included, the other doesn't. So is it inclusive or not, or ambiguous, or sometimes one sometimes the other? If it's sometimes one, sometimes the other, how can I tell if the number is included?