Decentralized adaptive output-feedback stabilization of large-scale nonlinear systems with time-varying delays and unknown high-frequency-gain signs

In this paper, we propose a decentralized adaptive output-feedback controller for a class of large-scale nonlinear systems with time-varying delays and unknown high-frequency-gain signs. We establish global asymptotic stabilization results, without using Razumikhin Theorem or constructing Lyapunov-Krasovskii functionals. The paper enlarges the class of large-scale nonlinear systems for which global decentralized adaptive output- feedback controller can be designed.