We study the number of periodic orbits that bifurcate from a cubic polynomial vector field having two period annuli via piecewise perturbations. The cubic planar system (x',y')= (-y((x-1)² + y²),x((x-1)² + y²) has simultaneously a center at the origin and at infinity. We study, up to first order averaging analysis, the bifurcation of periodic orbits from the two period annuli first separately and second simultaneously. This problem is an generalization of PerTor2014 to the piecewise systems class. When the polynomial perturbation has degree n, we prove that the inner and outer Abelian integrals are rational functions and we provide an upper bound for the number of zeros. When the perturbation is cubic, the same degree than the unperturbed v...
Agraïments: The third author is partially supported by FCT/Portugal through UID/MAT/04459/2013.We st...
Agraïments: FEDER-UNAB10-4E-378. The second author is supported by a Ciência sem Fronteiras-CNPq gra...
This paper presents new results on the bifurcation of medium and small limit cycles from the periodi...
The period annuli of the planar vector field x' = −yF(x, y), y' = xF(x, y), where the set {F(x, y) =...
nd $, the inner and outer Abelian integrals are rational functions and we provide an upper bound for...
AbstractLet z˙=f(z) be an holomorphic differential equation having a center at p, and consider the f...
Agraïments: The first and third authors are partially supported by the grant TIN2008-04752/TI
The period annuli of the planar vector field x' = −yF(x, y), y' = xF(x, y), where the set {F(x, y) =...
In this paper, we study the bifurcation of limit cycles of the periodic annulus of two classes of cu...
In this paper we study the maximum number of limit cycles bifurcating from the periodic orbits of th...
In this paper we study the maximum number of limit cycles bifurcating from the periodic orbits of th...
We prove that perturbing the two periodic annuli of the quadratic polynomial reversible Lotka-Volter...
Agraïments: FEDER-UNAB10-4E-378. The second author is supported by a Ciência sem Fronteiras-CNPq gra...
Agraïments: The first author is supported by a Ciência sem Fronteiras-CNPq grant number 201002/ 2012...
In this paper we study the limit cycles which can bifurcate from the periodic orbits of the center l...
Agraïments: The third author is partially supported by FCT/Portugal through UID/MAT/04459/2013.We st...
Agraïments: FEDER-UNAB10-4E-378. The second author is supported by a Ciência sem Fronteiras-CNPq gra...
This paper presents new results on the bifurcation of medium and small limit cycles from the periodi...
The period annuli of the planar vector field x' = −yF(x, y), y' = xF(x, y), where the set {F(x, y) =...
nd $, the inner and outer Abelian integrals are rational functions and we provide an upper bound for...
AbstractLet z˙=f(z) be an holomorphic differential equation having a center at p, and consider the f...
Agraïments: The first and third authors are partially supported by the grant TIN2008-04752/TI
The period annuli of the planar vector field x' = −yF(x, y), y' = xF(x, y), where the set {F(x, y) =...
In this paper, we study the bifurcation of limit cycles of the periodic annulus of two classes of cu...
In this paper we study the maximum number of limit cycles bifurcating from the periodic orbits of th...
In this paper we study the maximum number of limit cycles bifurcating from the periodic orbits of th...
We prove that perturbing the two periodic annuli of the quadratic polynomial reversible Lotka-Volter...
Agraïments: FEDER-UNAB10-4E-378. The second author is supported by a Ciência sem Fronteiras-CNPq gra...
Agraïments: The first author is supported by a Ciência sem Fronteiras-CNPq grant number 201002/ 2012...
In this paper we study the limit cycles which can bifurcate from the periodic orbits of the center l...
Agraïments: The third author is partially supported by FCT/Portugal through UID/MAT/04459/2013.We st...
Agraïments: FEDER-UNAB10-4E-378. The second author is supported by a Ciência sem Fronteiras-CNPq gra...
This paper presents new results on the bifurcation of medium and small limit cycles from the periodi...