The geometry of quadratic polynomial differential systems with a finite and an infinite saddle-node (A,B)

Autor: Artés, Joan C., Rezende, Alex C., Oliveira, Regilene D. S.

The goal is to make a global study of the family QsnSN of all real quadratic polynomial differential systems which have a finite semi-elemental saddle-node and an infinite saddle-node formed by the collision of two infinite singular points. This fami

Externí odkaz: http://arxiv.org/abs/1303.2525

Global phase portrait of a SIS model

Autor: Oliveira, Regilene D. S., Rezende, Alex C.

In the qualitative theory of ordinary differential equations, we can find many papers whose objective is the classification of all the possible topological phase portraits of a given family of differential system. Most of the studies rely on systems

Externí odkaz: http://arxiv.org/abs/1205.6015

QUADRATIC SYSTEMS WITH AN INVARIANT ALGEBRAIC CURVE OF DEGREE 3 AND A DARBOUX INVARIANT.

Autor: LLIBRE, JAUME¹ jllibre@mat.uab.cat, OLIVEIRA, REGILENE D. S.² regilene@icmc.usp.br, RODRIGUES, CAMILA A. B.³ c.r.lima@ufsc.br

Publikováno v: Electronic Journal of Differential Equations. 2021, Issue 1-104, p1-52. 52p.

Quadratic systems with an invariant conic having Darboux invariants

Autor: Llibre, Jaume, Oliveira, Regilene D. S.

Publikováno v: Recercat: Dipósit de la Recerca de Catalunya
Varias* (Consorci de Biblioteques Universitáries de Catalunya, Centre de Serveis Científics i Acadèmics de Catalunya)
Recercat. Dipósit de la Recerca de Catalunya
instname

The complete characterization of the phase portraits of real planar quadratic vector fields is very far to be completed. As this attempt is not possible in the whole class due to the large number of parameters (twelve, but, after affine transformatio

Externí odkaz: https://explore.openaire.eu/search/publication?articleId=dedup_wf_001::34db384a2e249fea9d7b412af8e02529
http://hdl.handle.net/2072/431014

Quadratic systems with invariant straight lines of total multiplicity two having Darboux invariants

Autor: Llibre, Jaume, Oliveira, Regilene D. S.

Publikováno v: Recercat: Dipósit de la Recerca de Catalunya
Varias* (Consorci de Biblioteques Universitáries de Catalunya, Centre de Serveis Científics i Acadèmics de Catalunya)
Recercat. Dipósit de la Recerca de Catalunya
instname

Agraïments: Both authors are also supported by the joint project CAPES-MECD grant PHB-2009-0025-PC. In this paper we present the global phase portraits in the Poincaré disc of the planar quadratic polynomial systems which admit invariant straight l

Externí odkaz: https://explore.openaire.eu/search/publication?articleId=dedup_wf_001::2a88fedb4b2dd8a51e67003c3c7a3fbf
http://hdl.handle.net/2072/408867