I am a short term scholar in a institute of U.S, and I will be in the institute for half a year. The institute will pay me some money as a consultant, but they said there is a 30% tax withholding of the money, unless a tax treaty with my country, China, entiles a lower rate or exemption. So I am asking if I am qualified for a exemption in this case, since I am not an employee of this institute. Thanks!