Poincaré in 1891 asked about the necessary and sufficient conditions in order to characterize when a polynomial differential system in the plane has a rational first integral. Here we solve this question for the class of ...

We classify the global phase portraits in the Poincaré disc of the quadratic polynomial Liénard differential systems where (x, y) ϵR 2 are the variables and a,b,c,d,e are real parameters.

In this paper we study the boundedness of solutions of some generalized Liénard type system under non usual conditions on evolved functions using the Second Method of Lyapunov

We consider a quadratic Lienard equation with an unbounded homoclinic loop, which is a solution tending in forward and backward time to a non-hyperbolic equilibrium point located at infinity. Under small time-periodic ...

We consider a quadratic Lienard equation with an unbounded homoclinic loop, which is a solution tending in forward and backward time to a non-hyperbolic equilibrium point located at infinity. Under small time-periodic ...

This book is the result of research done in the last two years by the "Group of Nonlinear Analysis" (GANol) of the Faculty of Exact and Natural Sciences and Surveying of the National University of the Northeast (UNNE). ...

Nesta dissertação estudamos critérios para determinar a existência, a não existência e a unicidade de ciclos limites de campos de vetores planares. Mais especificamente, estudamos equações de Lienard Äx + f(x; _ x) _ x + ...