How many universities with three initials are there in Shanghai? I wonder which one you need?
English name of Shanghai Maritime University: Shanghai Maritime University (SMU)
Shanghai University is called Shu for short.
Donghua University Donghua University is DHU for short.
University of Shanghai for Science and Technology SIT for short.
Shanghai Theatre Academy Shanghai TEDA College chain referred to as STA.
Shanghai Institute of Physical Education
As for you, there should be no three-letter abbreviation of the college you studied in Shanghai. The above examples are all undergraduate colleges.