<?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>0034-7426</journal-id>
<journal-title><![CDATA[Revista Colombiana de Matemáticas]]></journal-title>
<abbrev-journal-title><![CDATA[Rev.colomb.mat.]]></abbrev-journal-title>
<issn>0034-7426</issn>
<publisher>
<publisher-name><![CDATA[Universidad Nacional de Colombia y Sociedad Colombiana de Matemáticas]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S0034-74262008000200008</article-id>
<title-group>
<article-title xml:lang="en"><![CDATA[Existence of global weak solutions to a symmetrically hyperbolic system with a source]]></article-title>
<article-title xml:lang="es"><![CDATA[Existencia de soluciones débiles globales para un sistema hiperbólico simétrico con una fuente]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[SONG]]></surname>
<given-names><![CDATA[GUO-QIANG]]></given-names>
</name>
<xref ref-type="aff" rid="A01"/>
</contrib>
</contrib-group>
<aff id="A01">
<institution><![CDATA[,Nanjing University of Aeronautics and Astronautics  ]]></institution>
<addr-line><![CDATA[Nanjing ]]></addr-line>
<country>China</country>
</aff>
<pub-date pub-type="pub">
<day>15</day>
<month>12</month>
<year>2008</year>
</pub-date>
<pub-date pub-type="epub">
<day>15</day>
<month>12</month>
<year>2008</year>
</pub-date>
<volume>42</volume>
<numero>2</numero>
<fpage>221</fpage>
<lpage>232</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_arttext&amp;pid=S0034-74262008000200008&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_abstract&amp;pid=S0034-74262008000200008&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_pdf&amp;pid=S0034-74262008000200008&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="en"><p><![CDATA[In this paper the existence of global bounded weak solutions is obtained for the Cauchy problem of a symmetrically hyperbolic system with a source by using the theory of compensated compactness. This system arises in such areas as elasticity theory, magnetohydrodynamics, and enhanced oil recovery.]]></p></abstract>
<abstract abstract-type="short" xml:lang="es"><p><![CDATA[En este artículo se obtiene la existencia de soluciones débiles acotadas globalmente para el problema de Cauchy de un sistema simétricamente hiperbólico con una fuente, usando la teoría de la compacidad compensada. Este sistema surge en areas como la teoría de la elasticidad, la magneto-hidrodinámica y el mejoramiento en la recuperación de petróleo.]]></p></abstract>
<kwd-group>
<kwd lng="en"><![CDATA[Symmetrically hyperbolic system]]></kwd>
<kwd lng="en"><![CDATA[source terms]]></kwd>
<kwd lng="en"><![CDATA[weak solution]]></kwd>
<kwd lng="en"><![CDATA[compensatedcompactness method]]></kwd>
<kwd lng="es"><![CDATA[Sistema simétrico hiperbólico]]></kwd>
<kwd lng="es"><![CDATA[términos fuente]]></kwd>
<kwd lng="es"><![CDATA[solución débil]]></kwd>
<kwd lng="es"><![CDATA[método de compacidad compensada]]></kwd>
</kwd-group>
</article-meta>
</front><body><![CDATA[  <font size="2" face="verdana">      <p> <b> <font size="4">     <center> Existence of global weak solutions to a symmetrically hyperbolic system with a source </center> </font> </b> </p>      <p> <b> <font size="3">     <center> Existencia de soluciones d&eacute;biles globales para un sistema hiperb&oacute;lico sim&eacute;trico con una fuente </center> </font> </b> </p>      <p>     <center> GUO-QIANG SONG<sup>1</sup> </center> </p>      <p> <sup>1</sup>Nanjing University of Aeronautics and Astronautics, Nanjing, China. Email: <a href="mailto:gq_song2005@nuaa.edu.cn">gq_song2005@nuaa.edu.cn</a>     <br> </p>  <hr size="1">      <p> <b>     ]]></body>
<body><![CDATA[<center> Abstract </center> </b> </p>      <p> In this paper the existence of global bounded weak solutions is obtained for the Cauchy problem of a symmetrically hyperbolic system with a source by using the theory of compensated compactness. This system arises in such areas as elasticity theory, magnetohydrodynamics, and enhanced oil recovery. </p>      <p> <b> Key words: </b> Symmetrically hyperbolic system, source terms, weak solution, compensatedcompactness method. </p>  <hr size="1">  <i>2000 Mathematics Subject Classification: 35D05, 35L60.</i>  <hr size="1">      <p> <b>     <center> Resumen </center> </b> </p>      <p> En este art&iacute;culo se obtiene la existencia de soluciones d&eacute;biles acotadas globalmente para el problema de Cauchy de un sistema sim&eacute;tricamente hiperb&oacute;lico con una fuente, usando la teor&iacute;a de la compacidad compensada. Este sistema surge en areas como la teor&iacute;a de la elasticidad, la magneto-hidrodin&aacute;mica y el mejoramiento en la recuperaci&oacute;n de petr&oacute;leo. </p>      <p> <b> Palabras clave: </b> Sistema sim&eacute;trico hiperb&oacute;lico, t&eacute;rminos fuente, soluci&oacute;n d&eacute;bil, m&eacute;todo de compacidad compensada. </p>  <hr size="1">      <p> Texto completo disponible en <a href="pdf/rcm/v42n2/v42n2a08.pdf">PDF</a> </p>  <hr size="1">      <p> <b> <font size="3"> References </font> </b> </p>       <!-- ref --><p> [1] , T. L. & Wang, J., `On a hyperbolic system of conservation laws which is not strictly hyperbolic´, <i>J. 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Sb.</i> <i>73</i>,  (1967), 255-302. &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=S0034-7426200800020000800014&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --><center> <b>(Recibido en abril de 2008. Aceptado en septiembre de 2008)</b> </center> <hr size="1">      <p> Este art&iacute;culo se puede citar en <i>LaTeX</i> utilizando la siguiente referencia bibliogr&aacute;fica de <i>BibTeX</i>: </p> <code><font size="2">@ARTICLE{RCMv42n2a08,    <br>  &nbsp;&nbsp;&nbsp; AUTHOR &nbsp;= {Song, Guo-Qiang},    <br>  &nbsp;&nbsp;&nbsp; TITLE &nbsp; = {{Existence of global weak solutions to a symmetrically hyperbolic system with a source}},    <br>  &nbsp;&nbsp;&nbsp; JOURNAL = {Revista Colombiana de Matem&aacute;ticas},    <br> &nbsp;&nbsp;&nbsp; YEAR &nbsp;&nbsp; = {2008},    <br> &nbsp;&nbsp;&nbsp; volume &nbsp;= {42},    ]]></body>
<body><![CDATA[<br> &nbsp;&nbsp;&nbsp; number &nbsp;= {2},    <br> &nbsp;&nbsp;&nbsp; pages &nbsp; = {221-232}    <br> }</font></code>  <hr size="1"> </font>      ]]></body><back>
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