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Abstract
In real-time systems, jobs must complete before their deadlines. Oftentimes, real-time systems are required to change their operating modes due to changes in the operating environment. Whenever a system receives a Mode Change Request, the tasks that were running (now called "old mode tasks") should complete their execution, not release any more jobs, and the system should move into the new mode. It has been observed that executing the old mode jobs completely can negatively impact the new mode tasks and the system can become infeasible at some point in the schedule as the Mode Change Deadline cannot be met. In order to meet this Mode Change Deadline, the concept of Abort points has been introduced in this thesis. Abort points are the points in the schedule where the jobs of the old mode tasks can abort whenever there is a Mode Change Request without causing any effect on the new mode tasks. Genetic algorithms were used for computing these abort points. One or two Mode Independent tasks and their overall effect on the system has also been considered.