Complex sentence: In 1989 he was awarded the position of S.E.R.C. Senior Visiting Research Fellow with the University of St Andrews in Scotland, after which he became Associate Professor and Head of the Discipline of Computer Science at University of Newcastle in 1990.
Split into simpler sentences: In 1989 he was awarded the position of S.E.R.C. Senior Visiting Research Fellow with the University of St Andrews in Scotland. Professor Rosenberg then accepted the role of Associate Professor and Head of the Discipline of Computer Science at University of Newcastle in 1990.