摘要：Some criteria for asymptotic stability of linear and
time-invariant systems with constant point delays are derived.
Such criteria are concerned with the properties of robust
stability related to two relevant auxiliary delay-free systems
which are built by deleting the delayed dynamics or considering
that the delay is zero. Explicit asymptotic stability results,
easy to test, are given for both the unforced and closed-loop
systems when the stabilizing controller for one of the auxiliary
delay-free systems is used for the current time-delay system. The
proposed techniques include frequency domain analysis techniques
including the use of H∞ norms.
