As air distributor in a variable air volume system, the performance of slot diffuser is the best one, but the type of diffuser is too expensive, so at home many firms try to choose square diffuser.

For this point, many advanced control theories, such as adaptive control and fuzzy control, have been applied to variable structure system to reduce the chattering.

Using too many or too too few characters(variable) in Intrusion Detection System(IDS) leads to reduce recognizing correctness of IDS.