Robust stability of time-invariant systems with delays

This paper deals with the robust stability of time-invariant systems with delays. Using the frequency domain edge theorem developed by Fu, Olbrot and Polis (IEEE Tran. Automat. Contr. 34(1989), 813-820), which presents that the robust stability of a polytope generated by the convex combination of a number of quasipolynomials is equivalent to the stability of the edge quasipolynomials, the authors give the edge theorem of time domain version for the robust stability of the delay systems with rank-one uncertainty. An illustrative example was given in the last section.