Proskurnikov, A. V.; Yakubovich, V. A. The problem of absolute invariance for control systems with delay. (Russian) Zbl 1064.93016 Dokl. Akad. Nauk, Ross. Akad. Nauk 397, No. 5, 610-614 (2004). The authors prove a theorem for the existence of invariant universal regulators for which it is necessary to fulfill two preconditions. The first one asks for a solution to the equation \[ B(\lambda)S(\lambda) = F(\lambda) \] to be like \[ (\lambda) = \rho^{-1}(\lambda)P(\lambda), \] where \(\rho(\lambda)\) is a Hurwitz polynomial and \(P(\lambda)\) is the matrix quasipolynomial. The second condition supposes the existence of at least one stabilizing regulator. Reviewer: Andrei Zemskov (Moskva) Cited in 2 Documents MSC: 93B51 Design techniques (robust design, computer-aided design, etc.) 93D15 Stabilization of systems by feedback 93C80 Frequency-response methods in control theory 93C23 Control/observation systems governed by functional-differential equations Keywords:regulators; invariance; Hurwitz polynomial; delay; quasipolynomial PDFBibTeX XMLCite \textit{A. V. Proskurnikov} and \textit{V. A. Yakubovich}, Dokl. Akad. Nauk, Ross. Akad. Nauk 397, No. 5, 610--614 (2004; Zbl 1064.93016)