<?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>0120-419X</journal-id>
<journal-title><![CDATA[Revista Integración]]></journal-title>
<abbrev-journal-title><![CDATA[Integración - UIS]]></abbrev-journal-title>
<issn>0120-419X</issn>
<publisher>
<publisher-name><![CDATA[Universidad Industrial de Santander]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S0120-419X2012000200003</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[El problema de Steklov sobre el cono]]></article-title>
<article-title xml:lang="en"><![CDATA[The Steklov problem on the cone]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[MONTAÑO]]></surname>
<given-names><![CDATA[ÓSCAR ANDRéS]]></given-names>
</name>
<xref ref-type="aff" rid="A01"/>
</contrib>
</contrib-group>
<aff id="A01">
<institution><![CDATA[,Universidad del Valle Departamento de Matemáticas ]]></institution>
<addr-line><![CDATA[Cali ]]></addr-line>
<country>Colombia</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>12</month>
<year>2012</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>12</month>
<year>2012</year>
</pub-date>
<volume>30</volume>
<numero>2</numero>
<fpage>121</fpage>
<lpage>128</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_arttext&amp;pid=S0120-419X2012000200003&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_abstract&amp;pid=S0120-419X2012000200003&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_pdf&amp;pid=S0120-419X2012000200003&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[Sea (Mn, g) un cono de altura 0 &#8804; x n+1 &#8804; 1 en &#8477;n+1, dotado con una métrica rotacionalmente invariante 2ds² + &fnof;²(s)dw², donde dw² representa la métrica estándar sobre Sn-1, la esfera unitaria (n - 1)-dimensional. Supongamos que Ric(g) &#8805; 0. En este artículo demostramos que si h > 0 es la curvatura media sobre &#8706;M y v1 es el primer valor propio del problema de Steklov, entonces v1 &#8805; h.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[Let (Mn, g) be a cone of height 0 &#8804; x n+1 &#8804; 1 en &#8477;n+1, endowed with a rotationally invariant metric 2ds² + &fnof;²(s)dw², where dw² represents the standard metric on Sn-1, the (n - 1)-dimensional unit sphere. Assume Ric(g) &#8805; 0. In this paper we prove that if h > 0 is the mean curvature on &#8706;M and v1 is the first eigenvalue of the Steklov problem, then v1 &#8805; h.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[Problema de Steklov]]></kwd>
<kwd lng="es"><![CDATA[cono]]></kwd>
<kwd lng="es"><![CDATA[curvatura media]]></kwd>
<kwd lng="en"><![CDATA[Steklov problem]]></kwd>
<kwd lng="en"><![CDATA[cone]]></kwd>
<kwd lng="en"><![CDATA[mean curvature]]></kwd>
</kwd-group>
</article-meta>
</front><body><![CDATA[   <font size="2" face="Verdana">     <p align="center"><font size="4"><b><i>El problema de Steklov sobre el cono</i></b></font></p>      <p align="center">&Oacute;SCAR ANDR&Eacute;S MONTA&Ntilde;O</p>     <p align="center">Universidad del Valle, Departamento de Matem&aacute;ticas, Cali, Colombia.</p>     <p align="center"><i>Dedicado a Rafael Isaacs, a quien recuerdo siempre con mucho cari&ntilde;o e    <br> infinita gratitud por su valioso aporte en mi formaci&oacute;n acad&eacute;mica.</i></p>  <hr>      <p align="justify"><b><i>Resumen.</i></b> Sea (M<sup>n</sup>, g) un cono de altura 0 &le; x<sub>n+1</sub> &le; 1 en &#8477;<sup>n+1</sup>, dotado con una m&eacute;trica rotacionalmente invariante 2ds<sup>2</sup> + &fnof;<sup>2</sup>(s)dw<sup>2</sup>, donde dw<sup>2</sup> representa la m&eacute;trica est&aacute;ndar sobre S<sup>n-1</sup>, la esfera unitaria (n - 1)-dimensional. Supongamos que Ric(g) &ge; 0. En este art&iacute;culo demostramos que si h &gt; 0 es la curvatura media sobre <i>&part;M</i> y <i>v<sub>1</sub></i> es el primer valor propio del problema de Steklov, entonces <i>v<sub>1</sub></i> &ge; h.    <br> 	 <b><i>Palabras Claves:</i></b> Problema de Steklov, cono, curvatura media.    <br> <b><i>MSC2010:</i></b> 35P15, 53C20, 53C42, 53C43</p> <hr>     <p align="center"><font size="3"><b><i>The Steklov problem on the cone</i></b></font></p>      ]]></body>
<body><![CDATA[<p align="justify"><b><i>Abstract</i></b>. Let (M<sup>n</sup>, g) be a cone of height 0 &le; x<sub>n+1</sub> &le; 1 en &#8477;<sup>n+1</sup>, endowed with a rotationally invariant metric 2ds<sup>2</sup> + &fnof;<sup>2</sup>(s)dw<sup>2</sup>, where dw<sup>2</sup> represents the standard metric on S<sup>n-1</sup>, the (n - 1)-dimensional unit sphere. Assume Ric(g) &ge; 0. In this paper we prove that if h &gt; 0 is the mean curvature on <i>&part;</i>M and <i>v<sub>1</sub></i> is the first eigenvalue of the Steklov problem, then <i>v<sub>1</sub></i> &ge; h.    <br> 	 <b><i>Keywords:</i></b> Steklov problem, cone, mean curvature.</p> <hr>     <p align="justify">Texto Completo disponible en <a href ="pdf\rein\v30n2\v30n2a03.pdf">PDF</a></p> <hr>      <p align="left"><font size="3"><b><i>Referencias</i></b></font></p>      <!-- ref --><p align="justify">&#91;1&#93; Calder&oacute;n A.P., &quot;On an Inverse Boundary Value Problem&quot;, Comput. <i>Appl. Math.</i> 25 (2006), no. 2-3, 133–138.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=000017&pid=S0120-419X201200020000300001&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></p>      <!-- ref --><p align="justify">&#91;2&#93; Escobar J.F., &quot;Conformal Deformation of a Riemannian Metric to a Scalar Flat Metric with Constant Mean Curvature on the Boundary&quot;, <i>Ann. of Math.</i> 136 (1992), no. 2, 1–50.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=000019&pid=S0120-419X201200020000300002&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></p>      <!-- ref --><p align="justify">&#91;3&#93; Escobar J.F., &quot;The Yamabe problem on manifolds with Boundary&quot;, <i>J. Differential Geom.</i> 35 (1992) no. 1, 21–84.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=000021&pid=S0120-419X201200020000300003&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></p>      ]]></body>
<body><![CDATA[<!-- ref --><p align="justify">&#91;4&#93; Escobar J.F., &quot;The Geometry of the first Non-Zero Stekloff Eigenvalue&quot;, <i>J. Funct. Anal.</i> 150 (1997), no. 2, 544–556.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=000023&pid=S0120-419X201200020000300004&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></p>      <!-- ref --><p align="justify">&#91;5&#93; Escobar J.F., &quot;An isoperimetric inequality and the first Steklov Eigenvalue&quot;, <i>J. Funct. Anal.</i> 165 (1999), no. 1, 101–116.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=000025&pid=S0120-419X201200020000300005&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></p>      <!-- ref --><p align="justify">&#91;6&#93; Escobar J.F., &quot;A comparison theorem for the first non-zero Steklov Eigenvalue&quot;, <i>J. Funct. Anal.</i> 178 (2000), no. 1, 143–155.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=000027&pid=S0120-419X201200020000300006&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></p>      <!-- ref --><p align="justify">&#91;7&#93; Escobar J.F., &quot;Topics in PDE's and Differential Geometry&quot;, XII Escola de Geometria Diferencial. &#91;XII School of Differential Geometry&#93; Universidade Federal de Goi&aacute;s, Goi&acirc;nia, 2002. viii+88 pp.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=000029&pid=S0120-419X201200020000300007&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></p>      <!-- ref --><p align="justify">&#91;8&#93; Monta&ntilde;o O.A., &quot;The first non-zero Stekloff eigenvalue for conformal metrics on the ball&quot;, preprint.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=000031&pid=S0120-419X201200020000300008&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></p>      ]]></body>
<body><![CDATA[<!-- ref --><p align="justify">&#91;9&#93; Reilly R.C., &quot;Aplications of the Hessian operator in a Riemannian manifold&quot;, <i>Indiana Univ. Math. J.</i> 26 (1977), no. 3, 459–472.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=000033&pid=S0120-419X201200020000300009&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></p>      <!-- ref --><p align="justify">&#91;10&#93; Payne L.E., &quot;Some isoperimetric inequalities for harmonic functions&quot;, <i>SIAM J. Math. Anal.</i> 1 (1970), 354–359.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=000035&pid=S0120-419X201200020000300010&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></p>      <!-- ref --><p align="justify">&#91;11&#93; Steklov W., &quot;Sur les problemes fondamentaux de la physique math&eacute;matique&quot;, <i>Ann. Sci. &Eacute;cole Norm. Sup.</i> 19 (1902), no.3,    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=000037&pid=S0120-419X201200020000300011&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --> 455–490.</p>      <!-- ref --><p align="justify">&#91;12&#93; Weinstock R., &quot;Inequalities for a classical eigenvalue problem&quot;, <i>J. Rational Mech. Anal.</i> 3 (1954), 745–753.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=000039&pid=S0120-419X201200020000300012&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></p>      <!-- ref --><p align="justify">&#91;13&#93; Wang Q., Xia C., &quot;Sharp bounds for the first non-zero Stekloff eigenvalues&quot;, <i>J. Funct. Anal.</i> 257 (2009), no. 8, 2635–2644.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=000041&pid=S0120-419X201200020000300013&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></p>      ]]></body>
<body><![CDATA[<!-- ref --><p align="justify">&#91;14&#93; Xia C., &quot;Rigidity of compact manifolds with boundary and nonnegative Ricci curvature&quot;, <i>Proc. Amer. Math. Soc.</i> 125 (1997), no. 6, 1801–1806.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=000043&pid=S0120-419X201200020000300014&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></p> <hr>     <p align="justify"><sup>*</sup><i>E-mail:</i> <a href="mailto:oscar.montano@correounivalle.edu.co">oscar.montano@correounivalle.edu.co</a>    <br> <b>Recibido:</b> 13 de junio de 2012, <b>Aceptado:</b> 10 de septiembre de 2012.</p> </font>      ]]></body><back>
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