<?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>S0035-001X2003000600009</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Sensor distribuido para la detección de esfuerzos de umbral mediante rejillas de Bragg]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Márquez Borbón]]></surname>
<given-names><![CDATA[I.]]></given-names>
</name>
<xref ref-type="aff" rid="A01"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Shlyagin]]></surname>
<given-names><![CDATA[M.G.]]></given-names>
</name>
<xref ref-type="aff" rid="A01"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Miridonov]]></surname>
<given-names><![CDATA[S.V.]]></given-names>
</name>
<xref ref-type="aff" rid="A01"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Spirin]]></surname>
<given-names><![CDATA[V.V.]]></given-names>
</name>
<xref ref-type="aff" rid="A01"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[López]]></surname>
<given-names><![CDATA[R.M.]]></given-names>
</name>
<xref ref-type="aff" rid="A01"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Kuzin]]></surname>
<given-names><![CDATA[E.A.]]></given-names>
</name>
<xref ref-type="aff" rid="A02"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[May Alarcón]]></surname>
<given-names><![CDATA[M.]]></given-names>
</name>
<xref ref-type="aff" rid="A01"/>
</contrib>
</contrib-group>
<aff id="A01">
<institution><![CDATA[,Centro de Investigación Científica y de Educación Superior de Ensenada División de Física Aplicada ]]></institution>
<addr-line><![CDATA[Ensenada Baja California]]></addr-line>
<country>México</country>
</aff>
<aff id="A02">
<institution><![CDATA[,Instituto Nacional de Astrofísica, Óptica y Electrónica  ]]></institution>
<addr-line><![CDATA[Puebla ]]></addr-line>
<country>México</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>12</month>
<year>2003</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>12</month>
<year>2003</year>
</pub-date>
<volume>49</volume>
<numero>6</numero>
<fpage>542</fpage>
<lpage>548</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S0035-001X2003000600009&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S0035-001X2003000600009&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S0035-001X2003000600009&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[Algunas aplicaciones sólo requieren que la variable en observación sea detectada dentro de un intervalo preestablecido, mediante un sistema de advertencia temprana o de alarma. Estos sistemas deben generar una señal de alarma cuando la variable de monitoreo se aproxime o cruce el límite de la zona de peligro. En este trabajo se propone un sensor distribuido, basado en un arreglo de rejillas de Bragg iguales, así como una técnica para interrogar al sensor utilizando una sola longitud de onda de prueba. Se discute el principio de operación del sensor y se presentan resultados experimentales de esta técnica para la detección distribuida de exceso de esfuerzo.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[For early warning and alarm systems, it is required to detect appearance of the monitored parameter, such as temperature or strain, within some predetermined interval. A system must generate an alarm signal when the monitored parameter approaches near or crosses the limit of the dangerous zone. For such applications, we propose a simple distributed sensor based on a large array of equal Bragg gratings. An interrogation of the sensor is performed at a fixed wavelength. We discuss a principle of operation of the sensor and present results of experimental demonstration of this technique for distributed detection of excess strain.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[Rejillas de Bragg]]></kwd>
<kwd lng="es"><![CDATA[sensor distribuido]]></kwd>
<kwd lng="es"><![CDATA[esfuerzo]]></kwd>
<kwd lng="en"><![CDATA[Bragg gratings]]></kwd>
<kwd lng="en"><![CDATA[distributed sensor]]></kwd>
<kwd lng="en"><![CDATA[strain]]></kwd>
</kwd-group>
</article-meta>
</front><body><![CDATA[ <p align="justify"><font face="verdana" size="4">Instrumentaci&oacute;n</font></p>      <p align="center">&nbsp;</p>     <p align="center"><font face="verdana" size="4"><b>Sensor distribuido para la detecci&oacute;n de esfuerzos de umbral mediante rejillas de Bragg</b></font></p>      <p align="center">&nbsp;</p>     <p align="center"><font face="verdana" size="2"><b>I. M&aacute;rquez Borb&oacute;n<sup>1</sup>, M.G. Shlyagin<sup>1</sup>, S.V. Miridonov<sup>1</sup>, V.V. Spirin<sup>1</sup>, R.M. L&oacute;pez<sup>1</sup>, E.A. Kuzin<sup>2</sup>, M. May Alarc&oacute;n<sup>2</sup></b></font></p>      <p align="justify">&nbsp;</p>     <p align="justify"><font face="verdana" size="2"><i><sup>1</sup> CICESE, Divisi&oacute;n de F&iacute;sica Aplicada Apartado Postal No.2732, Ensenada, B.C., M&eacute;xico 22860</i></font></p>      <p align="justify"><font face="verdana" size="2"><i><sup>2</sup> Instituto Nacional Astrof&iacute;sica, &Oacute;ptica y Electr&oacute;nica, Apartado Postal 51 y 216, 7200, Puebla, Puebla, M&eacute;xico</i></font></p>      <p align="justify">&nbsp;</p>     <p align="justify"><font face="verdana" size="2">Recibido el 3 de julio de 2002.     ]]></body>
<body><![CDATA[<br>   Aceptado el 23 de mayo de 2003.</font></p>      <p align="justify">&nbsp;</p>     <p align="justify"><font face="verdana" size="2"><b>Resumen</b></font></p>      <p align="justify"><font face="verdana" size="2">Algunas aplicaciones s&oacute;lo requieren que la variable en observaci&oacute;n sea detectada dentro de un intervalo preestablecido, mediante un sistema de advertencia temprana o de alarma. Estos sistemas deben generar una se&ntilde;al de alarma cuando la variable de monitoreo se aproxime o cruce el l&iacute;mite de la zona de peligro. En este trabajo se propone un sensor distribuido, basado en un arreglo de rejillas de Bragg iguales, as&iacute; como una t&eacute;cnica para interrogar al sensor utilizando una sola longitud de onda de prueba. Se discute el principio de operaci&oacute;n del sensor y se presentan resultados experimentales de esta t&eacute;cnica para la detecci&oacute;n distribuida de exceso de esfuerzo.</font></p>      <p align="justify"><font face="verdana" size="2"><b>Palabras clave:</b> Rejillas de Bragg; sensor distribuido; esfuerzo.</font></p>      <p align="justify">&nbsp;</p>     <p align="justify"><font face="verdana" size="2"><b>Abstract</b></font></p>      <p align="justify"><font face="verdana" size="2">For early warning and alarm systems, it is required to detect appearance of the monitored parameter, such as temperature or strain, within some predetermined interval. A system must generate an alarm signal when the monitored parameter approaches near or crosses the limit of the dangerous zone. For such applications, we propose a simple distributed sensor based on a large array of equal Bragg gratings. An interrogation of the sensor is performed at a fixed wavelength. We discuss a principle of operation of the sensor and present results of experimental demonstration of this technique for distributed detection of excess strain.</font></p>      <p align="justify"><font face="verdana" size="2"><b>Keywords:</b> Bragg gratings; distributed sensor; strain.</font></p>      <p align="justify"><font face="verdana" size="2">PACS: 42.81.Pa; 42.81.Wg; 42.79.Dj</font></p>     ]]></body>
<body><![CDATA[<p align="justify">&nbsp;</p>     <p align="justify"><font face="verdana" size="2"><a href="/pdf/rmf/v49n6/v49n6a9.pdf" target="_blank">DESCARGAR ART&Iacute;CULO EN FORMATO PDF</a></font></p>     <p align="justify">&nbsp;</p>      <p align="justify"><font face="verdana" size="2"><b>Agradecimientos</b></font></p>      <p align="justify"><font face="verdana" size="2">Este trabajo fue soportado por el Consejo Nacional de Ciencia y Tecnolog&iacute;a a trav&eacute;s del proyecto #35460U, y por el Instituto Mexicano del Petr&oacute;leo, a trav&eacute;s del proyecto FIES 97&#45;04 IV.</font></p>      <p align="justify">&nbsp;</p>     <p align="justify"><font face="verdana" size="2"><b>Referencias bibliogr&aacute;ficas</b></font></p>      <!-- ref --><p align="justify"><font face="verdana" size="2">1. K.T.V. Grattan y T. 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