<?xml version="1.0" encoding="ISO-8859-1"?><article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<front>
<journal-meta>
<journal-id>1870-3542</journal-id>
<journal-title><![CDATA[Revista mexicana de física E]]></journal-title>
<abbrev-journal-title><![CDATA[Rev. mex. fís. E]]></abbrev-journal-title>
<issn>1870-3542</issn>
<publisher>
<publisher-name><![CDATA[Sociedad Mexicana de Física]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S1870-35422011000100011</article-id>
<title-group>
<article-title xml:lang="en"><![CDATA[Conservative nonlinear oscillators in Abel's mechanical problem]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Muñoz]]></surname>
<given-names><![CDATA[R.]]></given-names>
</name>
<xref ref-type="aff" rid="A01"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Fernández-Anaya]]></surname>
<given-names><![CDATA[G.]]></given-names>
</name>
<xref ref-type="aff" rid="A02"/>
</contrib>
</contrib-group>
<aff id="A01">
<institution><![CDATA[,Universidad Autónoma de la Ciudad de México  ]]></institution>
<addr-line><![CDATA[México D.F.]]></addr-line>
<country>México</country>
</aff>
<aff id="A02">
<institution><![CDATA[,Universidad Iberoamericana Departamento de Física y Matemáticas ]]></institution>
<addr-line><![CDATA[México D.F.]]></addr-line>
<country>México</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>06</month>
<year>2011</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>06</month>
<year>2011</year>
</pub-date>
<volume>57</volume>
<numero>1</numero>
<fpage>67</fpage>
<lpage>72</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S1870-35422011000100011&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S1870-35422011000100011&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S1870-35422011000100011&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="en"><p><![CDATA[We study a family of conservative, truly nonlinear, oscillators, arising from particular solutions of Abel's mechanical problem. An exact period-to-amplitude relation is produced for each instance. The lagrangian and hamiltonian formulations of such systems are discussed, along with their relations with the harmonic oscillator.]]></p></abstract>
<abstract abstract-type="short" xml:lang="es"><p><![CDATA[Se estudia una familia de osciladores no lineales, intrínsecamente no analíticos, que surgen como soluciones particulares del problema mecánico de Abel. Se incluye en cada caso la expresión exacta del periodo en función de la amplitud de las oscilaciones. Las formulaciones lagrangiana y hamiltoniana son discutidas, así como la relación que los mencionados sistemas guardan con el oscilador armónico.]]></p></abstract>
<kwd-group>
<kwd lng="en"><![CDATA[Nonlinear oscillators]]></kwd>
<kwd lng="en"><![CDATA[analytical mechanics]]></kwd>
<kwd lng="en"><![CDATA[Abel's mechanical problem]]></kwd>
<kwd lng="es"><![CDATA[Osciladores no lineales]]></kwd>
<kwd lng="es"><![CDATA[mecánica analítica]]></kwd>
<kwd lng="es"><![CDATA[problema mecánico de Abel]]></kwd>
</kwd-group>
</article-meta>
</front><body><![CDATA[  	    <p align="justify"><font face="verdana" size="4">Ense&ntilde;anza</font></p> 	    <p align="center"><font face="verdana" size="2">&nbsp;</font></p> 	    <p align="center"><font face="verdana" size="4"><b>Conservative nonlinear oscillators in Abel's mechanical problem</b></font></p> 	    <p align="center"><font face="verdana" size="2">&nbsp;</font></p> 	    <p align="center"><font face="verdana" size="2"><b>R. Mu&ntilde;oz, G. Fern&aacute;ndez&#150;Anaya</b></font></p> 	    <p align="justify"><font face="verdana" size="2">&nbsp;</font></p> 	    <p align="justify"><font face="verdana" size="2"><i>Universidad Aut&oacute;noma de la Ciudad de M&eacute;xico, Centro Hist&oacute;rico, Fray Servando Teresa de Mier 92 y 99, Col. Obrera, Del. Cuauhtemoc, M&eacute;xico, D.F. 06080, M&eacute;xico, e&#150;mail:</i><a href="mailto:rodrigo.munoz@uacm.edu.mx">rodrigo.munoz@uacm.edu.mx</a>.</font></p> 	    <p align="justify"><font face="verdana" size="2"><i>Universidad Iberoamericana, Departamento de F&iacute;sica y Matem&aacute;ticas, Av. Prolongaci&oacute;n Paseo de la Reforma 880, Col. Lomas de Santa Fe, Del. Alvaro Obregon, M&eacute;xico D.F., 01219, M&eacute;xico, </i><i>e&#150;mail:</i> <a href="mailto:guillermo.fernandez@uia.mx">guillermo.fernandez@uia.mx</a></font></p> 	    <p align="justify"><font face="verdana" size="2">&nbsp;</font></p> 	    ]]></body>
<body><![CDATA[<p align="justify"><font face="verdana" size="2">Recibido el 13 de diciembre de 2010    <br>     Aceptado el 24 de marzo de 2011</font></p> 	    <p align="justify"><font face="verdana" size="2">&nbsp;</font></p> 	    <p align="justify"><font face="verdana" size="2"><b>Abstract</b></font></p> 	    <p align="justify"><font face="verdana" size="2">We study a family of conservative, <i>truly nonlinear,</i> oscillators, arising from particular solutions of Abel's mechanical problem. An exact period&#150;to&#150;amplitude relation is produced for each instance. The lagrangian and hamiltonian formulations of such systems are discussed, along with their relations with the harmonic oscillator.</font></p> 	    <p align="justify"><font face="verdana" size="2"><b>Keywords:</b> Nonlinear oscillators; analytical mechanics; Abel's mechanical problem.</font></p> 	    <p align="justify"><font face="verdana" size="2">&nbsp;</font></p> 	    <p align="justify"><font face="verdana" size="2"><b>Resumen</b></font></p> 	    <p align="justify"><font face="verdana" size="2">Se estudia una familia de osciladores no lineales, intr&iacute;nsecamente no anal&iacute;ticos, que surgen como soluciones particulares del problema mec&aacute;nico de Abel. Se incluye en cada caso la expresi&oacute;n exacta del periodo en funci&oacute;n de la amplitud de las oscilaciones. Las formulaciones lagrangiana y hamiltoniana son discutidas, as&iacute; como la relaci&oacute;n que los mencionados sistemas guardan con el oscilador arm&oacute;nico.</font></p> 	    <p align="justify"><font face="verdana" size="2"><b>Descriptores:</b> Osciladores no lineales; mec&aacute;nica anal&iacute;tica; problema mec&aacute;nico de Abel.</font></p> 	    ]]></body>
<body><![CDATA[<p align="justify"><font face="verdana" size="2">&nbsp;</font></p> 	    <p align="justify"><font face="verdana" size="2">PACS: 01.55.+b; 02.30.Xx; 02.30.Hq; 02.30.Em</font></p> 	    <p align="justify"><font face="verdana" size="2">&nbsp;</font></p> 	    <p align="justify"><font face="verdana" size="2"><a href="/pdf/rmfe/v57n1/v57n1a11.pdf" target="_blank">DESCARGAR ART&Iacute;CULO EN FORMATO PDF</a></font></p> 	    <p align="justify"><font face="verdana" size="2">&nbsp;</font></p> 	    <p align="justify"><font face="verdana" size="2"><b>Acknowledgments</b></font></p> 	    <p align="justify"><font face="verdana" size="2">The support of SNI&#150;CONACYT (Mexico) is duly acknowledged.</font></p> 	    <p align="justify"><font face="verdana" size="2">&nbsp;</font></p> 	    <p align="justify"><font face="verdana" size="2"><b>References</b></font></p> 	    <!-- ref --><p align="justify"><font face="verdana" size="2">1. Z.K. Peng, Z.Q. Lang, S.A. Billings, and G.R. 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