“…Several approaches for adaptive optimal control of nonlinear systems with model uncertainty have been developed recently, mostly using a data-based paradigm. For example, methods based on fuzzy control and combination of feedforward and feedback control [31], [32] or adaptive state observers [33], [34] were developed to implement adaptive, decentralized, and fault-tolerant optimal control for nonlinear systems, including large-scale systems, and a similar method based on neural networks was proposed by [35]. However, these methods typically require a specific structure for either the model or mismatch, which may not encompass the true system.…”