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\section{Application domains}

Having discussed the development and architectural considerations, we can now explore the application domains for FPDS. We have found that FPDS allows for better predictability of the WCET compared to scheduling that allows arbitrary preemption. This is because with FPDS the number of preemption points are limited. However, when deadline misses occur with FPDS, there is a higher chance that the task that misses its deadline is a higher priority task due to the limitation of preemption points as compared to arbitrary preemptions. \\

We will now divide the application domains into two main groups, control systems and HQ-video. For each of these groups, we will discuss whether using FPDS is suitable. \\

\subsection{Control systems}

We find that the area of control systems can once again be divided into two main groups. In the first group we have control applications where tasks that miss their deadline preferable have a lower priority. An example would be a fuel injection system in a car. We would like to miss tasks that control the amount of fuel injected into the engine rather than tasks that control whether fuel is injected into the engine at all. If the amount of fuel injected into the engine is wrong, the car can still function even though the ride may be bumpy. However, if the fuel is not provided to the engine, the car will not be able to function. In scenarios that pertain to the first group, schedules with arbitrary preemptions should be used in favor of FPDS because they would reduce the chance that a higher priority task misses its deadline. \\

In the second group, we have applications where missing any deadline would be equally disastrous. An example would be a space shuttle where any deadline miss may cause the shuttle to crash. In these cases, it is better to use FPDS with limited preemption points because FPDS allows us to predict the WCET more accurately.

\subsection{HQ-Video}

For high quality videos sound is of a higher priority than the image. A deadline miss for the audio would greatly decrease the perceived quality, but a deadline miss for images would not be as noticeable. In this case, we should choose scheduling with arbitrary preemption points so that the chance missing an audio deadline will be reduced.