The major contributions of this dissertation were as follows:The problem of non-fragile H_2control for linear systems was concerned in the presence of controller gain variation.

Then we can really start to look at the genetic variation within the species and gain insight into some of the genes involved in drug resistance or virulence.

In order to recover the message carrying signal at the receiving end, we use adaptive controller to compensate the variation of channel gain when the channel is time-varying.