<?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>0035-001X</journal-id>
<journal-title><![CDATA[Revista mexicana de física]]></journal-title>
<abbrev-journal-title><![CDATA[Rev. mex. fis.]]></abbrev-journal-title>
<issn>0035-001X</issn>
<publisher>
<publisher-name><![CDATA[Sociedad Mexicana de Física]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S0035-001X2008000600012</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Implementación electrónica de sistemas lineales en R²]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Campos-Cantón]]></surname>
<given-names><![CDATA[I]]></given-names>
</name>
<xref ref-type="aff" rid="A01"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Tesheira]]></surname>
<given-names><![CDATA[S]]></given-names>
</name>
<xref ref-type="aff" rid="A01"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Jiménez-Calvillo]]></surname>
<given-names><![CDATA[C]]></given-names>
</name>
<xref ref-type="aff" rid="A01"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Campos-Cantón]]></surname>
<given-names><![CDATA[E]]></given-names>
</name>
<xref ref-type="aff" rid="A02"/>
</contrib>
</contrib-group>
<aff id="A01">
<institution><![CDATA[,Universidad Autónoma de San Luis Potosí Facultad de Ciencias ]]></institution>
<addr-line><![CDATA[San Luis Potosí SLP]]></addr-line>
<country>Mexico</country>
</aff>
<aff id="A02">
<institution><![CDATA[,Universidad Autónoma de San Luis Potosí Departamento de Físico Matemáticas ]]></institution>
<addr-line><![CDATA[San Luis Potosí SLP]]></addr-line>
<country>México</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>12</month>
<year>2008</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>12</month>
<year>2008</year>
</pub-date>
<volume>54</volume>
<numero>6</numero>
<fpage>468</fpage>
<lpage>472</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S0035-001X2008000600012&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S0035-001X2008000600012&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S0035-001X2008000600012&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[Este trabajo presenta la instrumentación electrónica de un sistema lineal de segundo orden. Se muestran los retratos de fase del sistema lineal, los cuales presentan el diagrama de un nodo, un foco y un centro en el origen. El desarrollo experimental es fácil y económico de realizar debido a que utiliza solamente elementos pasivos (resistencias, capacitores) y amplificadores operacionales.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[A second order linear system suited for analog instrumentation is presented. Shown are the corresponding phase portrait nodes, a root focus and a central point. The experimental prototype is of easy implementation and of low cost as it is comprised only of passive elements (i.e resistors, capacitors) and operational amplifiers.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[Retrato de fase]]></kwd>
<kwd lng="es"><![CDATA[electrónica analógica]]></kwd>
<kwd lng="es"><![CDATA[ecuaciones diferenciales ordinarias]]></kwd>
<kwd lng="en"><![CDATA[Phase portrait]]></kwd>
<kwd lng="en"><![CDATA[analog electronic]]></kwd>
<kwd lng="en"><![CDATA[ordinary differential equations]]></kwd>
</kwd-group>
</article-meta>
</front><body><![CDATA[ <p align="justify"><font face="verdana" size="4">Instrumentaci&oacute;n</font></p>     <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>     <p align="center"><font face="verdana" size="4"><b>Implementaci&oacute;n electr&oacute;nica de sistemas lineales en R<sup>2</sup></b></font></p>     <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>     <p align="center"><font face="verdana" size="2"><b>I. Campos&#150;Cant&oacute;n&ordf;, S. Tesheira&ordf;, C. Jim&eacute;nez&#150;Calvillo&ordf; y E. Campos&#150;Cant&oacute;n<sup>b</sup></b></font></p>     <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>     <p align="justify"><font face="verdana" size="2"><i>&ordf; Facultad de Ciencias, Universidad Aut&oacute;noma de San Luis Potos&iacute;, &Aacute;lvaro Obreg&oacute;n 64, 78000, San Luis Potos&iacute;, SLP, Mexico, </i>e&#150;mail: <a href="mailto:icampos@galia.fc.uaslp.mx">icampos@galia.fc.uaslp.mx</a></font></p>     <p align="justify"><font face="verdana" size="2"><i><sup>b </sup>Departamento de F&iacute;sico Matem&aacute;ticas, Universidad Aut&oacute;noma de San Luis Potos&iacute;, &Aacute;lvaro Obreg&oacute;n 64, 78000, San Luis Potos&iacute;, SLP, M&eacute;xico, </i>e&#150;mail: <a href="mailto:ecamp@uaslp.mx">ecamp@uaslp.mx</a></font></p>     <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>     <p align="justify"><font face="verdana" size="2">Recibido el 17 de septiembre de 2008    ]]></body>
<body><![CDATA[<br> Aceptado el 28 de noviembre de 2008</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">Este trabajo presenta la instrumentaci&oacute;n electr&oacute;nica de un sistema lineal de segundo orden. Se muestran los retratos de fase del sistema lineal, los cuales presentan el diagrama de un nodo, un foco y un centro en el origen. El desarrollo experimental es f&aacute;cil y econ&oacute;mico de realizar debido a que utiliza solamente elementos pasivos (resistencias, capacitores) y amplificadores operacionales.</font></p>     <p align="justify"><font face="verdana" size="2"><b>Descriptores: </b>Retrato de fase; electr&oacute;nica anal&oacute;gica; ecuaciones diferenciales ordinarias.</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">A second order linear system suited for analog instrumentation is presented. Shown are the corresponding phase portrait nodes, a root focus and a central point. The experimental prototype is of easy implementation and of low cost as it is comprised only of passive elements <i>(i.e </i>resistors, capacitors) and operational amplifiers.</font></p>     <p align="justify"><font face="verdana" size="2"><b>Keywords: </b>Phase portrait; analog electronic; ordinary differential equations. </font></p>     <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>     ]]></body>
<body><![CDATA[<p align="justify"><font face="verdana" size="2">PACS: 07.50.&#150;e; 84.32.&#150;y; 02.30.Hq</font></p>     <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>     <p align="justify"><font face="verdana" size="2"><a href="/pdf/rmf/v54n6/v54n6a12.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>Referencias</b></font></p>     <!-- ref --><p align="justify"><font face="verdana" size="2">1. L. Perko, <i>Differential Equations   and Dinamical  Systems </i>(Springer&#150;Verlag, 1991).</font>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8347570&pid=S0035-001X200800060001200001&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --><!-- ref --><p align="justify"><font face="verdana" size="2">2. M.W. Hirsch and S. Smale, <i>Differential Equation, Dinamical Systems, and Linear Algebra </i>(Academic Press, 1974).</font>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8347571&pid=S0035-001X200800060001200002&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --><!-- ref --><p align="justify"><font face="verdana" size="2">3. D.G. Zill, <i>Ecuaciones Diferenciales con Aplicaciones de Modelado </i>(Thomson, 2007).</font>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8347572&pid=S0035-001X200800060001200003&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --><!-- ref --><p align="justify"><font face="verdana" size="2">4. M.E. Van Valkenburg, <i>Network analysis </i>N. J. Englewood Cliffs (Prentice Hall, 1964).</font>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8347573&pid=S0035-001X200800060001200004&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --> ]]></body><back>
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<person-group person-group-type="author">
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</back>
</article>
