When the institution was renamed into Namibia University of Science and Technology in 2015, Tjivikua continued to lead it, now in the position of vice-chancellor, until March 2019.
His family soon moved to Katutura as a result of the forced removal of blacks from Old Location, and he continued his schooling there.
Tjivikua left Namibia in June 1979 to study chemistry in the United States at Rockland Community College (1979–1980) and then Lincoln University (1980–1983), from which he graduated cum laude.
He was a well recognized researcher at that time, and he worked as assistant professor of chemistry at Lincoln University from 1990 to 1995.
When the institution was renamed into Namibia University of Science and Technology in 2015, Tjivikua continued to lead it, now in the position of vice-chancellor, until March 2019.