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<dc:title>Uniqueness of limit cycles for quadratic vector fields</dc:title>
<dc:creator>Bravo, José Luis</dc:creator>
<dc:creator>Fernández, Manuel</dc:creator>
<dc:creator>Ojeda, Ignacio</dc:creator>
<dc:creator>Sánchez, Fernándo</dc:creator>
<dc:subject>Abel equation</dc:subject>
<dc:subject>Ecuación de Abel</dc:subject>
<dc:subject>Closed solution</dc:subject>
<dc:subject>Solución en forma cerrada</dc:subject>
<dc:subject>Periodic solution</dc:subject>
<dc:subject>Solución periódica</dc:subject>
<dc:subject>Limit cycles</dc:subject>
<dc:subject>Ciclos límite</dc:subject>
<dc:description>Producción Científica</dc:description>
<dc:description>This article deals with the study of the number of limit&#xd;
cycles surrounding a critical point of a quadratic planar vector field,&#xd;
which, in normal form, can be written as x&#xd;
′ = a1x − y − a3x&#xd;
2 + (2a2 +&#xd;
a5)xy+a6y&#xd;
2&#xd;
, y&#xd;
′ = x+a1y+a2x&#xd;
2+(2a3+a4)xy−a2y&#xd;
2&#xd;
. In particular, we&#xd;
study the semi-varieties defined in terms of the parameters a1, a2, . . . , a6&#xd;
where some classical criteria for the associated Abel equation apply.&#xd;
The proofs will combine classical ideas with tools from computational&#xd;
algebraic geometry.</dc:description>
<dc:description>Agencia Estatal de Investigación - Fondo Europeo de Desarrollo Regional (grant MTM 2011-22751)</dc:description>
<dc:description>Junta de Extremadura (grant GR15055)</dc:description>
<dc:description>Ministerio de Economía, Industria y Competitividad - Fondo Europeo de Desarrollo Regional  (grant MTM2015-65764-C3-1-P)</dc:description>
<dc:date>2020-04-06T19:33:18Z</dc:date>
<dc:date>2020-04-06T19:33:18Z</dc:date>
<dc:date>2019</dc:date>
<dc:type>info:eu-repo/semantics/article</dc:type>
<dc:type>info:eu-repo/semantics/acceptedVersion</dc:type>
<dc:identifier>Discrete and Continuous Dynamical Systems, 2019, vol. 39, n. 1. p. 483-502</dc:identifier>
<dc:identifier>1553-5231</dc:identifier>
<dc:identifier>http://uvadoc.uva.es/handle/10324/40727</dc:identifier>
<dc:identifier>10.3934/dcds.2019020</dc:identifier>
<dc:language>eng</dc:language>
<dc:relation>http://www.aimsciences.org/article/doi/10.3934/dcds.2019020</dc:relation>
<dc:rights>Attribution-NonCommercial-NoDerivatives 4.0 Internacional</dc:rights>
<dc:rights>info:eu-repo/semantics/openAccess</dc:rights>
<dc:rights>http://creativecommons.org/licenses/by-nc-nd/4.0/</dc:rights>
<dc:rights>© 2019 American Institute of Mathematical Sciences</dc:rights>
<dc:format>application/pdf</dc:format>
<dc:publisher>American Institute of Mathematical Sciences</dc:publisher>
<europeana:object>https://uvadoc.uva.es/bitstream/10324/40727/4/Uniqueness-of-limit-cycles.pdf.jpg</europeana:object>
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<europeana:type>TEXT</europeana:type>
<europeana:rights>http://creativecommons.org/licenses/by-nc-nd/4.0/</europeana:rights>
<europeana:dataProvider>UVaDOC. Repositorio Documental de la Universidad de Valladolid</europeana:dataProvider>
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