<?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>1665-6423</journal-id>
<journal-title><![CDATA[Journal of applied research and technology]]></journal-title>
<abbrev-journal-title><![CDATA[J. appl. res. technol]]></abbrev-journal-title>
<issn>1665-6423</issn>
<publisher>
<publisher-name><![CDATA[Universidad Nacional Autónoma de México, Instituto de Ciencias Aplicadas y Tecnología]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S1665-64232008000300002</article-id>
<title-group>
<article-title xml:lang="en"><![CDATA[State variables monitoring using a class of nonlinear observer based estimator, applied to continuous bio-system]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Aguilar-López]]></surname>
<given-names><![CDATA[Ricardo]]></given-names>
</name>
<xref ref-type="aff" rid="A01"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Acevedo-Gómez]]></surname>
<given-names><![CDATA[Ricardo]]></given-names>
</name>
<xref ref-type="aff" rid="A01"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Neria González]]></surname>
<given-names><![CDATA[María Isabel]]></given-names>
</name>
<xref ref-type="aff" rid="A02"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Domínguez-Bocanegra]]></surname>
<given-names><![CDATA[Alma Rosa]]></given-names>
</name>
<xref ref-type="aff" rid="A01"/>
</contrib>
</contrib-group>
<aff id="A01">
<institution><![CDATA[,Instituto Politécnico Nacional Centro de Investigación y de Estudios Avanzados Departamento de Biotecnología y Bioingeniería]]></institution>
<addr-line><![CDATA[México D.F.]]></addr-line>
<country>MEXICO</country>
</aff>
<aff id="A02">
<institution><![CDATA[,Tecnológico de Estudios Superiores de Ecatepec División de Ingeniería Química y Bioquímica ]]></institution>
<addr-line><![CDATA[Ecatepec Estado de México]]></addr-line>
</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>6</volume>
<numero>3</numero>
<fpage>147</fpage>
<lpage>158</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S1665-64232008000300002&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S1665-64232008000300002&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S1665-64232008000300002&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="en"><p><![CDATA[In this work, the state estimation of key variables such as biomass and products of a sulfate reducing bacterium is predicted by using only sulfate (substrate) concentration measurements under the assumption of an unknown kinetic term. The process was developed by continuous culture, where the mathematical kinetic model for the biomass, sulfate and sulfide concentrations is presented and tuned using experimental data. The design of the nonlinear state estimator takes into account an adaptive gain. The results of the proposed estimation methodology were generated via numerical simulation; they showed a satisfactory performance.]]></p></abstract>
<abstract abstract-type="short" xml:lang="es"><p><![CDATA[En este trabajo se predice la estimación de estados como la biomasa y la concentración de productos de una bacteria sulfato reductora empleando únicamente mediciones de la concentración de sulfato (sustrato) bajo la hipótesis de una cinética de consumo de sulfato desconocida. El proceso fue considerado como un cultivo continuo, donde el modelo cinético correspondiente para las concentraciones de biomasa, sulfato y sulfuro fue corroborado con datos experimentales. El diseño de la metodología de estimación propuesta considera una ganancia adaptable. Los resultados de estimación fueron generados por medio de simulaciones numéricas y muestran un comportamiento satisfactorio.]]></p></abstract>
<kwd-group>
<kwd lng="en"><![CDATA[robust estimation]]></kwd>
<kwd lng="en"><![CDATA[bioreactor model]]></kwd>
<kwd lng="en"><![CDATA[anaerobic biosystem]]></kwd>
<kwd lng="es"><![CDATA[Estimación robusta]]></kwd>
<kwd lng="es"><![CDATA[modelo de un birreactor]]></kwd>
<kwd lng="es"><![CDATA[bio-sistema anaerobio]]></kwd>
</kwd-group>
</article-meta>
</front><body><![CDATA[  	    <p align="center"><font face="verdana" size="4"><b>State variables monitoring using a class of nonlinear observer based estimator, applied to continuous bio&#45;system</b></font></p>  	    <p align="center"><font face="verdana" size="2">&nbsp;</font></p>  	    <p align="center"><font face="verdana" size="2"><b>Ricardo Aguilar&#45;L&oacute;pez<sup>1</sup>, Ricardo Acevedo&#45;G&oacute;mez<sup>1</sup>, Mar&iacute;a Isabel Neria Gonz&aacute;lez<sup>2</sup> and Alma Rosa Dom&iacute;nguez&#45;Bocanegra</b></font><font face="verdana" size="2"><b><sup>1</sup></b></font></p>      <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>  	    <p align="justify"><font face="verdana" size="2"><sup><i>1 </i></sup><i>Departamento de Biotecnolog&iacute;a y Bioingenier&iacute;a CINVESTAV&#45;IPN, Av. Instituto Polit&eacute;cnico Nacional No. 2508, San Pedro Zacatenco, M&eacute;xico, D.F. 07360, MEXICO E&#45;mail.&#45;</i> <a href="mailto:raguilar@cinvestav.mx">raguilar@cinvestav.mx</a> Phone.&#45; + 52 55 5747 3800, ext. 4307.</font></p>      <p align="justify"><font face="verdana" size="2"><sup><i>2 </i></sup><i>Divisi&oacute;n de Ingenier&iacute;a Qu&iacute;mica y Bioqu&iacute;mica, Tecnol&oacute;gico de Estudios Superiores de Ecatepec, Av. Tecnol&oacute;gico s/n Esq. Av. Carlos Hank Gonz&aacute;lez Col. Valle de An&aacute;huac C.P. 55210, Ecatepec Estado de 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"><b>ABSTRACT</b></font></p>  	    <p align="justify"><font face="verdana" size="2">In this work, the state estimation of key variables such as biomass and products of a sulfate reducing bacterium is predicted by using only sulfate (substrate) concentration measurements under the assumption of an unknown kinetic term. The process was developed by continuous culture, where the mathematical kinetic model for the biomass, sulfate and sulfide concentrations is presented and tuned using experimental data. The design of the nonlinear state estimator takes into account an adaptive gain. The results of the proposed estimation methodology were generated via numerical simulation; they showed a satisfactory performance.</font></p>  	    ]]></body>
<body><![CDATA[<p align="justify"><font face="verdana" size="2"><b>keywords</b>: robust estimation, bioreactor model, anaerobic biosystem.</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">En este trabajo se predice la estimaci&oacute;n de estados como la biomasa y la concentraci&oacute;n de productos de una bacteria sulfato reductora empleando &uacute;nicamente mediciones de la concentraci&oacute;n de sulfato (sustrato) bajo la hip&oacute;tesis de una cin&eacute;tica de consumo de sulfato desconocida. El proceso fue considerado como un cultivo continuo, donde el modelo cin&eacute;tico correspondiente para las concentraciones de biomasa, sulfato y sulfuro fue corroborado con datos experimentales. El dise&ntilde;o de la metodolog&iacute;a de estimaci&oacute;n propuesta considera una ganancia adaptable. Los resultados de estimaci&oacute;n fueron generados por medio de simulaciones num&eacute;ricas y muestran un comportamiento satisfactorio.</font></p>  	    <p align="justify"><font face="verdana" size="2"><b>Palabras clave</b>: Estimaci&oacute;n robusta, modelo de un birreactor, bio&#45;sistema anaerobio.</font></p>  	    <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>  	    <p align="justify"><font face="verdana" size="2"><a href="/pdf/jart/v6n3/v6n3a2.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>REFERENCES</b></font></p>  	    <!-- ref --><p align="justify"><font face="verdana" size="2">&#91;1&#93;&nbsp;J. Gonz&aacute;lez, G. Fern&aacute;ndez, R. Aguilar, M. A. Barr&oacute;n and J. Alvarez&#45;Ramirez. 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