<?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>S1870-35422012000100003</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Desarrollo de un sistema para medir tiempos en experimentos de movimiento rectilíneo]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Camero-Berrones]]></surname>
<given-names><![CDATA[R.G.]]></given-names>
</name>
<xref ref-type="aff" rid="A01"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Zapata-Torres]]></surname>
<given-names><![CDATA[M.]]></given-names>
</name>
<xref ref-type="aff" rid="A01"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Calzadilla-Amaya]]></surname>
<given-names><![CDATA[O.]]></given-names>
</name>
<xref ref-type="aff" rid="A02"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Guillen Rodríguez]]></surname>
<given-names><![CDATA[J.]]></given-names>
</name>
<xref ref-type="aff" rid="A03"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Laría-Menchaca]]></surname>
<given-names><![CDATA[J.]]></given-names>
</name>
<xref ref-type="aff" rid="A04"/>
</contrib>
</contrib-group>
<aff id="A01">
<institution><![CDATA[,Instituto Politécnico Nacional Centro de Investigación en Ciencia Aplicada y Tecnología Avanzada ]]></institution>
<addr-line><![CDATA[México D.F.]]></addr-line>
<country>México</country>
</aff>
<aff id="A02">
<institution><![CDATA[,Universidad de La Habana Facultad de Física ]]></institution>
<addr-line><![CDATA[La Habana ]]></addr-line>
<country>Cuba</country>
</aff>
<aff id="A03">
<institution><![CDATA[,Instituto Tecnológico y de Estudios Superiores de Monterrey  ]]></institution>
<addr-line><![CDATA[Altamira Tamaulipas]]></addr-line>
<country>México</country>
</aff>
<aff id="A04">
<institution><![CDATA[,Universidad Autónoma de Tamaulipas Facultad de Ingeniería ]]></institution>
<addr-line><![CDATA[Tampico Tamaulipas]]></addr-line>
<country>México</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>06</month>
<year>2012</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>06</month>
<year>2012</year>
</pub-date>
<volume>58</volume>
<numero>1</numero>
<fpage>18</fpage>
<lpage>23</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S1870-35422012000100003&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S1870-35422012000100003&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S1870-35422012000100003&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[Se desarrolló un sistema para medir tiempos en experimentos de movimiento rectilíneo. Este sistema utiliza foto compuertas, como sensores, y una tarjeta de sonido de la computadora para la adquisición de datos. Los sensores de movimiento fueron comunicados con la computadora mediante un arreglo compuertas lógicas XOR y la serial proveniente de los sensores fue adquirida por medio de la interfaz de entrada de la tarjeta de sonido. Para la habilitación de la tarjeta de sonido y el procesamiento de los datos, se utilizó el software de MATLAB. El sistema desarrollado puede construirse con componentes económicos, y fue utilizado en dos experimentos para verificar su funcionamiento, mostrando aproximaciones cercanas a los modelos teóricos.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[It was developed a system to measure times using photo gates and a computer's sound card on rectilinear motion experiments. The movement sensors were connected to the computer through a XOR logic gate array, the signal from the sensors was fed to the computer's sound card input line. MATLAB was used to acquire and processing data and a specialized add-on software activated the hardware to read the signals produced by the photo gates. The system developed can be built with low cost items and it was tested with two different setup to evaluate and compare theoretical versus experimental data resulting in good agreement.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[Computadoras en educación]]></kwd>
<kwd lng="es"><![CDATA[teoría del aprendizaje]]></kwd>
<kwd lng="es"><![CDATA[laboratorio de física en escuela secundaria]]></kwd>
<kwd lng="en"><![CDATA[Computer education]]></kwd>
<kwd lng="en"><![CDATA[learning theory]]></kwd>
<kwd lng="en"><![CDATA[physics laboratory in high school]]></kwd>
</kwd-group>
</article-meta>
</front><body><![CDATA[  	    <p align="justify"><font face="verdana" size="4">Ense&ntilde;anza</font></p>      <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>     <p align="center"><font face="verdana" size="4"><b>Desarrollo de un sistema para medir tiempos en experimentos de movimiento rectil&iacute;neo</b></font></p>     <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>     <p align="center"><font face="verdana" size="2"><b>R.G. Camero&#45;Berrones<sup>a</sup>, M. Zapata&#45;Torres<sup>a</sup>, O. Calzadilla&#45;Amaya<sup>b</sup>, J. Guillen Rodr&iacute;guez<sup>c</sup>, y J. Lar&iacute;a&#45;Menchaca<sup>d</sup></b></font></p>      <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>     <p align="justify"><font face="verdana" size="2"><i><sup>a</sup> Centro de Investigaci&oacute;n en Ciencia Aplicada y Tecnolog&iacute;a Avanzada del Instituto Polit&eacute;cnico Nacional Calzada Legaria No. 694, Col. Irrigaci&oacute;n, M&eacute;xico, D.F. 11500, M&eacute;xico, e&#45;mail:</i> <a href="mailto:gabriela_camero@hotmail.com">gabriela_camero@hotmail.com</a>; <a href="mailto:martinjzapata@hotmail.com">martinjzapata@hotmail.com</a></font></p>     <p align="justify"><font face="verdana" size="2"><i><sup>b</sup> Facultad de F&iacute;sica, Universidad de La Habana, San L&aacute;zaro y L. 10400, La Habana, Cuba. </i></font></p>     <p align="justify"><font face="verdana" size="2"><i><sup>c</sup> Instituto Tecnol&oacute;gico y de Estudios Superiores de Monterrey Campus Tampico, Boulevard Petrocel Km. 1.3 Puerto Industrial, Altamira, Tamaulipas, M&eacute;xico, 89600, M&eacute;xico. </i></font></p>     ]]></body>
<body><![CDATA[<p align="justify"><font face="verdana" size="2"><i><sup>d</sup> Facultad de Ingenier&iacute;a, Universidad Aut&oacute;noma de Tamaulipas, Campus Tampico, Tampico, Tamaulipas, M&eacute;xico.</i></font></p>      <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>     <p align="justify"><font face="verdana" size="2">Recibido el 28 de noviembre de 2011;     <br>   Aceptado el 23 de enero de 2012</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 desarroll&oacute; un sistema para medir tiempos en experimentos de movimiento rectil&iacute;neo. Este sistema utiliza foto compuertas, como sensores, y una tarjeta de sonido de la computadora para la adquisici&oacute;n de datos. Los sensores de movimiento fueron comunicados con la computadora mediante un arreglo compuertas l&oacute;gicas XOR y la serial proveniente de los sensores fue adquirida por medio de la interfaz de entrada de la tarjeta de sonido. Para la habilitaci&oacute;n de la tarjeta de sonido y el procesamiento de los datos, se utiliz&oacute; el software de MATLAB. El sistema desarrollado puede construirse con componentes econ&oacute;micos, y fue utilizado en dos experimentos para verificar su funcionamiento, mostrando aproximaciones cercanas a los modelos te&oacute;ricos.</font></p>      <p align="justify"><font face="verdana" size="2"><b>Descriptores:</b> Computadoras en educaci&oacute;n; teor&iacute;a del aprendizaje; laboratorio de f&iacute;sica en escuela secundaria.</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> 	    ]]></body>
<body><![CDATA[<p align="justify"><font face="verdana" size="2">It was developed a system to measure times using photo gates and a computer's sound card on rectilinear motion experiments. The movement sensors were connected to the computer through a XOR logic gate array, the signal from the sensors was fed to the computer's sound card input line. MATLAB was used to acquire and processing data and a specialized add&#45;on software activated the hardware to read the signals produced by the photo gates. The system developed can be built with low cost items and it was tested with two different setup to evaluate and compare theoretical versus experimental data resulting in good agreement.</font></p>  	    <p align="justify"><font face="verdana" size="2"><b>Keywords:</b> Computer education; learning theory; physics laboratory in high school. </font></p> 	    <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>     <p align="justify"><font face="verdana" size="2">PACS: 01.50.Lc.; 01.40.Ha.; 01.30.Ia.</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/v58n1/v58n1a3.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. A. Pontes, <i>Rev. Eur. Ense&ntilde;. Divul. Cien.</i> <b>3</b> (2006) 251.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8457593&pid=S1870-3542201200010000300001&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>      ]]></body>
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