Palavra-chave: BIFURCATION

CLOSED ORBIT SINGULARITY NON-SMOOTH VECTOR FIELDS LIMIT CYCLE CENTER AVERAGING NONSMOOTH DYNAMICAL SYSTEMS NORMAL FORM ASYMPTOTIC STABILITY STRUCTURAL STABILITY CYCLE SHILNIKOV PROBLEM DISCONTINUOUS VECTOR FIELD VERSAL UNFOLDING FOLD-FOLD LOOP FILIPPOV SYSTEMS FIRST INTEGRAL STABILITY REFRACTIVE VECTOR FIELD DIFFEOMORPHISM VECTOR FIELD PERIODIC ORBIT REGULARIZATION HAMILTONIAN