工业现场控制属于强实时系统还是弱实时系统？为什么

Laura哦呵呵

大家好，最近老师留了个题目（如题)，我搜了一些回答，但还是不太理解，请大家帮忙点拨一下。谢谢！

ITALPLANT精密输送系统

A system is said to be real-time if the total correctness of an operation depends not only upon its logical correctness but also upon the time in which it is performed. Real-time systems, as well as their deadlines, are classified by the consequence of missing a deadline:

Hard – missing a deadline is a total system failure.
Firm – infrequent deadline misses are tolerable but may degrade the system's quality of service. The usefulness of a result is zero after its deadline.
Soft – the usefulness of a result degrades after its deadline, thereby degrading the system's quality of service.

魍者归来

工业现场控制，这个范围太大了。