As numerical control (NC) technique is becoming prevalent in advanced manufacturing industry, there is an increasing demand for more complex, sophisticated, and dependable hard real-time computing systems, where periodic and aperiodic tasks generally co-exist. Both periodic tasks, such as cutter compensation, interpolation, position control, etc, and aperiodic tasks created by paroxysmal events must be completed within their deadlines. Meanwhile, timing constraints are essential for the correct running of t...