Palavra-chave: LIMIT CYCLE

AVERAGE SYNCHRONIZATION SINGULARIDADE SISTEMAS DINÂMICOS NON-SMOOTH VECTOR FIELDS LIENARD EQUATION LINEAR VECTOR FIELD LIAPOUNOV-SCHIMIDT REDUCTION ESTABILIDADE ESTRUTURAL BROWER THEORY HAMILTONIAN BIFURCATION POLICYCLE REGULARIZATION SINGULARITY BIFURCATIONS ATTRACTOR MINIMAL SET INTEGRABLE SYSTEMS AVERAGING INVARIANT VARIETY EQUILIBRIUM PENDULUM INVARIANT TORUS CENTER AVERAGING METHOD NONSMOOTH DYNAMICAL SYSTEMS PIECEWISE SMOOTH SYSTEMS ISOCHRONOUS CENTER PERIODIC ORBIT ASYMPTOTIC STABILITY DULAC PROBLEM