Hello Sreedhar,
UAT means User Acceptance Test this gets performed by the end user who is going to use the application or the BO reports in your case. An end user will have their own testing scenarios based on their real time business experiences. Once you get UAT sign off it goes to Go-live.
UTC means Unit test Cases that is being prepared by the developer while doing development these are some tests that are being performed by the Developer in order to verify the correctness or robustness on the application that he has built.
Hope this helps
Regards
Niraj