Introduction to nonlinear systems; analysis by phase plane and describing function methods. Lyapunov stability theory. The Lure problem: Popov's method, circle criterion. Hyperstability. Hamiltonian, Lagrangian and gradient systems: physical examples and analysis. Stability of Hamiltonian systems. Periodic systems: Floquet-Lyapunov theory, Krein's stability theorem.
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M. Vidyasagar, Nonlinear systems analysis. 2nd Edition. Prentice Hall, 1993.
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