<?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>1665-2738</journal-id>
<journal-title><![CDATA[Revista mexicana de ingeniería química]]></journal-title>
<abbrev-journal-title><![CDATA[Rev. Mex. Ing. Quím]]></abbrev-journal-title>
<issn>1665-2738</issn>
<publisher>
<publisher-name><![CDATA[Universidad Autónoma Metropolitana, División de Ciencias Básicas e Ingeniería]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S1665-27382013000200015</article-id>
<title-group>
<article-title xml:lang="en"><![CDATA[Stabilization of third-order systems with possible complex conjugate poles and time delay]]></article-title>
<article-title xml:lang="es"><![CDATA[Estabilización de sistemas de tercer orden con posibles polos complejos conjugados y tiempo de retardo]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Hernández-Pérez]]></surname>
<given-names><![CDATA[M.A.]]></given-names>
</name>
<xref ref-type="aff" rid="A01"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[del Muro-Cuéllar]]></surname>
<given-names><![CDATA[B.]]></given-names>
</name>
<xref ref-type="aff" rid="A01"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Cortés-Rodríguez]]></surname>
<given-names><![CDATA[D.]]></given-names>
</name>
<xref ref-type="aff" rid="A01"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Araujo-Vargas]]></surname>
<given-names><![CDATA[I.]]></given-names>
</name>
<xref ref-type="aff" rid="A01"/>
</contrib>
</contrib-group>
<aff id="A01">
<institution><![CDATA[,Instituto Politécnico Nacional Escuela Superior de Ingeniería Mecánica y Eléctrica Unidad Culhuacan]]></institution>
<addr-line><![CDATA[México D.F.]]></addr-line>
<country>México</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>00</month>
<year>2013</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>00</month>
<year>2013</year>
</pub-date>
<volume>12</volume>
<numero>2</numero>
<fpage>351</fpage>
<lpage>360</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S1665-27382013000200015&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S1665-27382013000200015&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S1665-27382013000200015&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="en"><p><![CDATA[The stabilization problem of third-order, time-delay unstable linear systems is analyzed. The systems under consideration have one unstable and two stable poles, which may be complex conjugate. Necessary and sufficient conditions to guarantee the stability of the closed loop system by means of a static output feedback are provided. Using such conditions, a predictor scheme that improves the transient system performance is proposed. To illustrate the application of the proposed strategy, it is applied to an unstable continuously stirred tank reactor model. Simulation results are presented.]]></p></abstract>
<abstract abstract-type="short" xml:lang="es"><p><![CDATA[Este trabajo considera el problema de la estabilización de sistemas lineales con tiempo de retardo de tercer orden, con un polo inestable y dos estables, los cuales pueden ser complejos conjugados. Se presentan las condiciones necesarias y suficientes para asegurar la estabilidad del sistema en lazo cerrado por medio de una retroalimentación estática de la salida. Asimismo, usando el resultado anterior se propone un esquema predictor el cual mejora el desempeño transitorio del sistema. Finalmente, el desempeño de la estrategia de control propuesta es evaluado mediante su aplicación en simulación numérica a un reactor de tanque continuamente agitado inestable.]]></p></abstract>
<kwd-group>
<kwd lng="en"><![CDATA[delay]]></kwd>
<kwd lng="en"><![CDATA[complex conjugate poles]]></kwd>
<kwd lng="en"><![CDATA[predictor]]></kwd>
<kwd lng="en"><![CDATA[stabilization]]></kwd>
<kwd lng="es"><![CDATA[retardo]]></kwd>
<kwd lng="es"><![CDATA[polos complejos conjugados]]></kwd>
<kwd lng="es"><![CDATA[predictor y estabilización]]></kwd>
</kwd-group>
</article-meta>
</front><body><![CDATA[ <p align="justify"><font face="verdana" size="4">Simulaci&oacute;n y control</font></p>     <p align="justify">&nbsp;</p>      <p align="center"><font face="verdana" size="4"><b>Stabilization of third-order systems with possible complex conjugate poles and time delay</b></font></p>     <p align="center">&nbsp;</p>     <p align="center"><font face="verdana" size="3"><b>Estabilizaci&oacute;n de sistemas de tercer orden con posibles polos complejos conjugados y tiempo de retardo</b></font></p>     <p align="center">&nbsp;</p>     <p align="center"><font face="verdana" size="2"><b>M.A. Hern&aacute;ndez&#45;P&eacute;rez, B. del Muro&#45;Cu&eacute;llar<sup>1</sup>*, D. Cort&eacute;s&#45;Rodr&iacute;guez and I. Araujo&#45;Vargas</b></font></p>     <p align="center">&nbsp;</p>      <p align="justify"><font face="verdana" size="2"><i>Escuela Superior de Ingenier&iacute;a Mec&aacute;nica y El&eacute;ctrica, Unidad Culhuacan, Instituto Polit&eacute;cnico Nacional, M&eacute;xico D.F., 04430, M&eacute;xico.</i></font> <font face="verdana" size="2"><i>*Corresponding author. E&#45;mail:</i> <a href="mailto:bdelmuro@ipn.mx">bdelmuro@ipn.mx</a> <i>Tel. (52)56&#45;562058.</i></font></p>     <p align="justify">&nbsp;</p>      ]]></body>
<body><![CDATA[<p align="justify"><font face="verdana" size="2">Received July 8, 2012    <br> </font><font face="verdana" size="2"> Accepted April 8, 2013</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">The stabilization problem of third&#45;order, time&#45;delay unstable linear systems is analyzed. The systems under consideration have one unstable and two stable poles, which may be complex conjugate. Necessary and sufficient conditions to guarantee the stability of the closed loop system by means of a static output feedback are provided. Using such conditions, a predictor scheme that improves the transient system performance is proposed. To illustrate the application of the proposed strategy, it is applied to an unstable continuously stirred tank reactor model. Simulation results are presented.</font></p>  	    <p align="justify"><font face="verdana" size="2"><b>Keywords:</b> delay, complex conjugate poles, predictor, stabilization.</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">Este trabajo considera el problema de la estabilizaci&oacute;n de sistemas lineales con tiempo de retardo de tercer orden, con un polo inestable y dos estables, los cuales pueden ser complejos conjugados. Se presentan las condiciones necesarias y suficientes para asegurar la estabilidad del sistema en lazo cerrado por medio de una retroalimentaci&oacute;n est&aacute;tica de la salida. Asimismo, usando el resultado anterior se propone un esquema predictor el cual mejora el desempe&ntilde;o transitorio del sistema. Finalmente, el desempe&ntilde;o de la estrategia de control propuesta es evaluado mediante su aplicaci&oacute;n en simulaci&oacute;n num&eacute;rica a un reactor de tanque continuamente agitado inestable.</font></p>     <p align="justify"><font face="verdana" size="2"><b>Palabras clave:</b> retardo, polos complejos conjugados, predictor y estabilizaci&oacute;n.</font></p>      ]]></body>
<body><![CDATA[<p align="justify">&nbsp;</p>     <p align="justify"><font size="2" face="verdana"><a href="/pdf/rmiq/v12n2/v12n2a15.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>References</b></font></p>  	    <!-- ref --><p align="justify"><font face="verdana" size="2">Bequette, B.W. (2003). <i>Process Control: Modeling, Design and Simulation.</i> Prentice Hall.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8566436&pid=S1665-2738201300020001500001&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>  	    <!-- ref --><p align="justify"><font face="verdana" size="2">del Muro, B., Gonz&aacute;lez, O. A., &amp; Pedraza, Y. A. (2009). Stabilization of High Order Systems with Delay using a Predictor Schema. Augost 2&#45;5. Cancun Mexico. <i>IEEE 52nd International Midwest Symposium on Circuits and Systems.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8566438&pid=S1665-2738201300020001500002&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></i></font></p>  	    <!-- ref --><p align="justify"><font face="verdana" size="2">Fridman E. and Shaked U. (2002). An improved stabilization method for linear time&#45;delay systems. <i>Automatic Control 47,</i> 1931 &#45; 1937.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8566440&pid=S1665-2738201300020001500003&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>  	    ]]></body>
<body><![CDATA[<!-- ref --><p align="justify"><font face="verdana" size="2">Kawnish K. and Shoukat Choudhury M.A.A. (2012). A novel dead time compensator for stable processes with long dead times. <i>Journal of Process Control 22,</i> 612&#45;625.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8566442&pid=S1665-2738201300020001500004&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>  	    <!-- ref --><p align="justify"><font face="verdana" size="2">Kolmanovskii V.B. and Richard J. P. (1999). Stability of some linear systems with delays. <i>IEEE Transactions on Automatic Control 44,</i> 984&#45;989.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8566444&pid=S1665-2738201300020001500005&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>  	    <!-- ref --><p align="justify"><font face="verdana" size="2">Lee S. C., Qing&#45;Guo W. and Xiang C. (2010). Stabilization of all&#45;pole unstable delay processes by simple controllers. <i>Journal of Process Control 20,</i> 235&#45;239.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8566446&pid=S1665-2738201300020001500006&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>  	    <!-- ref --><p align="justify"><font face="verdana" size="2">Lee Y. S., Moon Y. S., Kwon W. H., and Park P. G. (2004). Delay Dependent Robust H<sub>&#8734;</sub> Control for Uncertain Systems with a State&#45;Delay. <i>Automatica 40,</i> 65&#45;72.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8566448&pid=S1665-2738201300020001500007&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>  	    <!-- ref --><p align="justify"><font face="verdana" size="2">Liu T., Zhang W. and Gu D. (2005). Analytical design of two&#45;degree&#45;of&#45;freedom control scheme for open&#45;loop unstable processes. <i>Journal of Process Control 15,</i> 559&#45;572.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8566450&pid=S1665-2738201300020001500008&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>     ]]></body>
<body><![CDATA[<!-- ref --><p align="justify"><font face="verdana" size="2">Lu X., Yong&#45;Sheng Y., Quing&#45;Guo W. and Wei&#45;Xing Z. (2005). A double two&#45;degree&#45;of&#45;freedom control scheme for improved control of unstable delay processes. <i>Journal of Process Control 15,</i> 605&#45;614.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8566452&pid=S1665-2738201300020001500009&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>  	    <!-- ref --><p align="justify"><font face="verdana" size="2">Mahmoud M.S. and Al&#45;Rayyah A.Y. (2009). Efficient parameterization to stability and feedback synthesis of linear time&#45;delay systems. <i>Control Theory Applications 3,</i> 1107&#45;1118.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8566454&pid=S1665-2738201300020001500010&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>  	    <!-- ref --><p align="justify"><font face="verdana" size="2">Marquez, J., del Muro, B., Velasco, M., and Alvarez, J. (2010). Control based in an observer scheme for first&#45;order systems with delay. <i>Revista Mexicana de Ingenier&iacute;a Qu&iacute;mica 9,</i>43&#45;52.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8566456&pid=S1665-2738201300020001500011&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>  	    <!-- ref --><p align="justify"><font face="verdana" size="2">Michiels W., Engelborghs K., Vansevenant P. and Roose D. (2002). Continuous pole placement for delay equations. <i>Automatica 38,</i> 747&#45;761.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8566458&pid=S1665-2738201300020001500012&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>  	    <!-- ref --><p align="justify"><font face="verdana" size="2">Munz, U., Ebenbauer C, Haag T., and Allgower F. (2009). Stability analysis of time&#45;delay systems with incommensurate delays using positive polynomials. <i>IEEE Transactions on Automatic Control 54,</i> 1019&#45;1024.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8566460&pid=S1665-2738201300020001500013&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>  	    ]]></body>
<body><![CDATA[<!-- ref --><p align="justify"><font face="verdana" size="2">Nesimioglu, B. S. and Soylemez M. T. (2010). A simple derivation of all stabilizing proportional controllers for first order time&#45;delay systems. <i>Asian Journal of Control 14,</i> 598&#45;604.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8566462&pid=S1665-2738201300020001500014&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>  	    <!-- ref --><p align="justify"><font face="verdana" size="2">Niculescu S. I. (2001). <i>Delay Effects on Stability. A Robust Control Approach.</i> Springer&#45;Verlag, London.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8566464&pid=S1665-2738201300020001500015&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>  	    <!-- ref --><p align="justify"><font face="verdana" size="2">Normey&#45;Rico J. E. and Camacho E. F. (2008). Simple robust dead&#45;time compensator for first order plus dead&#45;time unstable processes. <i>Industrial and Engineering Chemistry Research 47,</i> 4784&#45;4790.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8566466&pid=S1665-2738201300020001500016&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --> </font></p>     <!-- ref --><p align="justify"><font face="verdana" size="2">Normey&#45;Rico J. E. and Camacho E. F. (2009). Unified approach for robust dead&#45;time compensator design. <i>Journal of Process Control 19,</i> 38&#45;47.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8566468&pid=S1665-2738201300020001500017&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>  	    <!-- ref --><p align="justify"><font face="verdana" size="2">Qing&#45;Chang Z. (2006). <i>Robust Control of Time&#45;Delay Systems,</i> Springer.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8566470&pid=S1665-2738201300020001500018&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>  	    ]]></body>
<body><![CDATA[<!-- ref --><p align="justify"><font face="verdana" size="2">Rao, A.S. and Chidambaram M. (2006). Enhanced two&#45;degrees&#45;of&#45;freedom control strategy for second&#45;order unstable processes with time delay. <i>Industrial and Engineering Chemistry Research 45,</i> 3604&#45;3614.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8566472&pid=S1665-2738201300020001500019&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>  	    <!-- ref --><p align="justify"><font face="verdana" size="2">Richard J. P. (2003). Time&#45;Delay Systems: An Overview of Some Recent Advances and Open Problems. <i>Automatica 39,</i> 1667&#45;1694.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8566474&pid=S1665-2738201300020001500020&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>  	    <!-- ref --><p align="justify"><font face="verdana" size="2">Seshagiri A., Rao V. S. R. and Chidambaram M. (2007). Simple analytical design of modified smith predictor with improved performance for unstable first&#45;order plus time delay processes. <i>Industrial and Engineering Chemistry Research 46,</i> 4561&#45;4571.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8566476&pid=S1665-2738201300020001500021&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>  	    <!-- ref --><p align="justify"><font face="verdana" size="2">Silva, G. J. and Bhattacharyya S. P. (2005). <i>PID Controllers for Time&#45;Delay Systems,</i> Birkhuser, Boston, MA.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8566478&pid=S1665-2738201300020001500022&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>  	    <!-- ref --><p align="justify"><font face="verdana" size="2">Smith O.J.M. (1957). Closed control of loops with dead time. <i>Chemical Engineering Progress 53,</i> 217&#45;219.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8566480&pid=S1665-2738201300020001500023&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>  	    ]]></body>
<body><![CDATA[<!-- ref --><p align="justify"><font face="verdana" size="2">Walton, K. and Marshall J. E. (1987). Direct method for TDS stability analysis. <i>IEE Proceedings on Control Theory Applications 134,</i> 101&#45;107.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8566482&pid=S1665-2738201300020001500024&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>      ]]></body><back>
<ref-list>
<ref id="B1">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Bequette]]></surname>
<given-names><![CDATA[B.W.]]></given-names>
</name>
</person-group>
<source><![CDATA[Process Control: Modeling, Design and Simulation]]></source>
<year>2003</year>
<publisher-name><![CDATA[Prentice Hall]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B2">
<nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[del Muro]]></surname>
<given-names><![CDATA[B.]]></given-names>
</name>
<name>
<surname><![CDATA[González]]></surname>
<given-names><![CDATA[O. A.]]></given-names>
</name>
<name>
<surname><![CDATA[Pedraza]]></surname>
<given-names><![CDATA[Y. A.]]></given-names>
</name>
</person-group>
<article-title xml:lang="en"><![CDATA[Stabilization of High Order Systems with Delay using a Predictor Schema]]></article-title>
<source><![CDATA[IEEE 52nd International Midwest Symposium on Circuits and Systems]]></source>
<year>2009</year>
<publisher-loc><![CDATA[Cancun ]]></publisher-loc>
</nlm-citation>
</ref>
<ref id="B3">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Fridman]]></surname>
<given-names><![CDATA[E.]]></given-names>
</name>
<name>
<surname><![CDATA[Shaked]]></surname>
<given-names><![CDATA[U.]]></given-names>
</name>
</person-group>
<article-title xml:lang="en"><![CDATA[An improved stabilization method for linear time-delay systems]]></article-title>
<source><![CDATA[Automatic Control]]></source>
<year>2002</year>
<volume>47</volume>
<page-range>1931 - 1937</page-range></nlm-citation>
</ref>
<ref id="B4">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Kawnish]]></surname>
<given-names><![CDATA[K.]]></given-names>
</name>
<name>
<surname><![CDATA[Shoukat Choudhury]]></surname>
<given-names><![CDATA[M.A.A.]]></given-names>
</name>
</person-group>
<article-title xml:lang="en"><![CDATA[A novel dead time compensator for stable processes with long dead times]]></article-title>
<source><![CDATA[Journal of Process Control]]></source>
<year>2012</year>
<volume>22</volume>
<page-range>612-625</page-range></nlm-citation>
</ref>
<ref id="B5">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Kolmanovskii]]></surname>
<given-names><![CDATA[V.B.]]></given-names>
</name>
<name>
<surname><![CDATA[Richard]]></surname>
<given-names><![CDATA[J. P.]]></given-names>
</name>
</person-group>
<article-title xml:lang="en"><![CDATA[Stability of some linear systems with delays]]></article-title>
<source><![CDATA[IEEE Transactions on Automatic Control]]></source>
<year>1999</year>
<volume>44</volume>
<page-range>984-989</page-range></nlm-citation>
</ref>
<ref id="B6">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Lee]]></surname>
<given-names><![CDATA[S. C.]]></given-names>
</name>
<name>
<surname><![CDATA[Qing-Guo]]></surname>
<given-names><![CDATA[W.]]></given-names>
</name>
<name>
<surname><![CDATA[Xiang]]></surname>
<given-names><![CDATA[C.]]></given-names>
</name>
</person-group>
<article-title xml:lang="en"><![CDATA[Stabilization of all-pole unstable delay processes by simple controllers]]></article-title>
<source><![CDATA[Journal of Process Control]]></source>
<year>2010</year>
<volume>20</volume>
<page-range>235-239</page-range></nlm-citation>
</ref>
<ref id="B7">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Lee]]></surname>
<given-names><![CDATA[Y. S.]]></given-names>
</name>
<name>
<surname><![CDATA[Moon]]></surname>
<given-names><![CDATA[Y. S.]]></given-names>
</name>
<name>
<surname><![CDATA[Kwon]]></surname>
<given-names><![CDATA[W. H.]]></given-names>
</name>
<name>
<surname><![CDATA[Park]]></surname>
<given-names><![CDATA[P. G.]]></given-names>
</name>
</person-group>
<article-title xml:lang="en"><![CDATA[Delay Dependent Robust H&#8734; Control for Uncertain Systems with a State-Delay]]></article-title>
<source><![CDATA[Automatica]]></source>
<year>2004</year>
<volume>40</volume>
<page-range>65-72</page-range></nlm-citation>
</ref>
<ref id="B8">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Liu]]></surname>
<given-names><![CDATA[T.]]></given-names>
</name>
<name>
<surname><![CDATA[Zhang]]></surname>
<given-names><![CDATA[W.]]></given-names>
</name>
<name>
<surname><![CDATA[Gu]]></surname>
<given-names><![CDATA[D.]]></given-names>
</name>
</person-group>
<article-title xml:lang="en"><![CDATA[Analytical design of two-degree-of-freedom control scheme for open-loop unstable processes]]></article-title>
<source><![CDATA[Journal of Process Control]]></source>
<year>2005</year>
<volume>15</volume>
<page-range>559-572</page-range></nlm-citation>
</ref>
<ref id="B9">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Lu]]></surname>
<given-names><![CDATA[X.]]></given-names>
</name>
<name>
<surname><![CDATA[Yong-Sheng]]></surname>
<given-names><![CDATA[Y.]]></given-names>
</name>
<name>
<surname><![CDATA[Quing-Guo]]></surname>
<given-names><![CDATA[W.]]></given-names>
</name>
<name>
<surname><![CDATA[Wei-Xing]]></surname>
<given-names><![CDATA[Z.]]></given-names>
</name>
</person-group>
<article-title xml:lang="en"><![CDATA[A double two-degree-of-freedom control scheme for improved control of unstable delay processes]]></article-title>
<source><![CDATA[Journal of Process Control]]></source>
<year>2005</year>
<volume>15</volume>
<page-range>605-614</page-range></nlm-citation>
</ref>
<ref id="B10">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Mahmoud]]></surname>
<given-names><![CDATA[M.S.]]></given-names>
</name>
<name>
<surname><![CDATA[Al-Rayyah]]></surname>
<given-names><![CDATA[A.Y.]]></given-names>
</name>
</person-group>
<article-title xml:lang="en"><![CDATA[Efficient parameterization to stability and feedback synthesis of linear time-delay systems]]></article-title>
<source><![CDATA[Control Theory Applications]]></source>
<year>2009</year>
<volume>3</volume>
<page-range>1107-1118</page-range></nlm-citation>
</ref>
<ref id="B11">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Marquez]]></surname>
<given-names><![CDATA[J.]]></given-names>
</name>
<name>
<surname><![CDATA[del Muro]]></surname>
<given-names><![CDATA[B.]]></given-names>
</name>
<name>
<surname><![CDATA[Velasco]]></surname>
<given-names><![CDATA[M.]]></given-names>
</name>
<name>
<surname><![CDATA[Alvarez]]></surname>
<given-names><![CDATA[J.]]></given-names>
</name>
</person-group>
<article-title xml:lang="en"><![CDATA[Control based in an observer scheme for first-order systems with delay]]></article-title>
<source><![CDATA[Revista Mexicana de Ingeniería Química]]></source>
<year>2010</year>
<volume>9</volume>
<page-range>43-52</page-range></nlm-citation>
</ref>
<ref id="B12">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Michiels]]></surname>
<given-names><![CDATA[W.]]></given-names>
</name>
<name>
<surname><![CDATA[Engelborghs]]></surname>
<given-names><![CDATA[K.]]></given-names>
</name>
<name>
<surname><![CDATA[Vansevenant]]></surname>
<given-names><![CDATA[P.]]></given-names>
</name>
<name>
<surname><![CDATA[Roose]]></surname>
<given-names><![CDATA[D.]]></given-names>
</name>
</person-group>
<article-title xml:lang="en"><![CDATA[Continuous pole placement for delay equations]]></article-title>
<source><![CDATA[Automatica]]></source>
<year>2002</year>
<volume>38</volume>
<page-range>747-761</page-range></nlm-citation>
</ref>
<ref id="B13">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Munz]]></surname>
<given-names><![CDATA[U.]]></given-names>
</name>
<name>
<surname><![CDATA[Ebenbauer]]></surname>
<given-names><![CDATA[C]]></given-names>
</name>
<name>
<surname><![CDATA[Haag]]></surname>
<given-names><![CDATA[T.]]></given-names>
</name>
<name>
<surname><![CDATA[Allgower]]></surname>
<given-names><![CDATA[F.]]></given-names>
</name>
</person-group>
<article-title xml:lang="en"><![CDATA[Stability analysis of time-delay systems with incommensurate delays using positive polynomials]]></article-title>
<source><![CDATA[IEEE Transactions on Automatic Control]]></source>
<year>2009</year>
<volume>54</volume>
<page-range>1019-1024</page-range></nlm-citation>
</ref>
<ref id="B14">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Nesimioglu]]></surname>
<given-names><![CDATA[B. S.]]></given-names>
</name>
<name>
<surname><![CDATA[Soylemez]]></surname>
<given-names><![CDATA[M. T.]]></given-names>
</name>
</person-group>
<article-title xml:lang="en"><![CDATA[A simple derivation of all stabilizing proportional controllers for first order time-delay systems]]></article-title>
<source><![CDATA[Asian Journal of Control]]></source>
<year>2010</year>
<volume>14</volume>
<page-range>598-604</page-range></nlm-citation>
</ref>
<ref id="B15">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Niculescu]]></surname>
<given-names><![CDATA[S. I.]]></given-names>
</name>
</person-group>
<source><![CDATA[Delay Effects on Stability. A Robust Control Approach]]></source>
<year>2001</year>
<publisher-loc><![CDATA[London ]]></publisher-loc>
<publisher-name><![CDATA[Springer-Verlag]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B16">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Normey-Rico]]></surname>
<given-names><![CDATA[J. E.]]></given-names>
</name>
<name>
<surname><![CDATA[Camacho]]></surname>
<given-names><![CDATA[E. F.]]></given-names>
</name>
</person-group>
<article-title xml:lang="en"><![CDATA[Simple robust dead-time compensator for first order plus dead-time unstable processes]]></article-title>
<source><![CDATA[Industrial and Engineering Chemistry Research]]></source>
<year>2008</year>
<volume>47</volume>
<page-range>4784-4790</page-range></nlm-citation>
</ref>
<ref id="B17">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Normey-Rico]]></surname>
<given-names><![CDATA[J. E.]]></given-names>
</name>
<name>
<surname><![CDATA[Camacho]]></surname>
<given-names><![CDATA[E. F.]]></given-names>
</name>
</person-group>
<article-title xml:lang="en"><![CDATA[Unified approach for robust dead-time compensator design]]></article-title>
<source><![CDATA[Journal of Process Control]]></source>
<year>2009</year>
<volume>19</volume>
<page-range>38-47</page-range></nlm-citation>
</ref>
<ref id="B18">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Qing-Chang]]></surname>
<given-names><![CDATA[Z.]]></given-names>
</name>
</person-group>
<source><![CDATA[Robust Control of Time-Delay Systems]]></source>
<year>2006</year>
<publisher-name><![CDATA[Springer]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B19">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Rao]]></surname>
<given-names><![CDATA[A.S.]]></given-names>
</name>
<name>
<surname><![CDATA[Chidambaram]]></surname>
<given-names><![CDATA[M.]]></given-names>
</name>
</person-group>
<article-title xml:lang="en"><![CDATA[Enhanced two-degrees-of-freedom control strategy for second-order unstable processes with time delay]]></article-title>
<source><![CDATA[Industrial and Engineering Chemistry Research]]></source>
<year>2006</year>
<volume>45</volume>
<page-range>3604-3614</page-range></nlm-citation>
</ref>
<ref id="B20">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Richard]]></surname>
<given-names><![CDATA[J. P.]]></given-names>
</name>
</person-group>
<article-title xml:lang="en"><![CDATA[Time-Delay Systems: An Overview of Some Recent Advances and Open Problems]]></article-title>
<source><![CDATA[Automatica]]></source>
<year>2003</year>
<volume>39</volume>
<page-range>1667-1694</page-range></nlm-citation>
</ref>
<ref id="B21">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Seshagiri]]></surname>
<given-names><![CDATA[A.]]></given-names>
</name>
<name>
<surname><![CDATA[Rao]]></surname>
<given-names><![CDATA[V. S. R.]]></given-names>
</name>
<name>
<surname><![CDATA[Chidambaram]]></surname>
<given-names><![CDATA[M.]]></given-names>
</name>
</person-group>
<article-title xml:lang="en"><![CDATA[Simple analytical design of modified smith predictor with improved performance for unstable first-order plus time delay processes]]></article-title>
<source><![CDATA[Industrial and Engineering Chemistry Research]]></source>
<year>2007</year>
<volume>46</volume>
<page-range>4561-4571</page-range></nlm-citation>
</ref>
<ref id="B22">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Silva]]></surname>
<given-names><![CDATA[G. J.]]></given-names>
</name>
<name>
<surname><![CDATA[Bhattacharyya]]></surname>
<given-names><![CDATA[S. P.]]></given-names>
</name>
</person-group>
<source><![CDATA[PID Controllers for Time-Delay Systems]]></source>
<year>2005</year>
<publisher-loc><![CDATA[Boston^eMA MA]]></publisher-loc>
<publisher-name><![CDATA[Birkhuser]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B23">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Smith]]></surname>
<given-names><![CDATA[O.J.M.]]></given-names>
</name>
</person-group>
<article-title xml:lang="en"><![CDATA[Closed control of loops with dead time]]></article-title>
<source><![CDATA[Chemical Engineering Progress]]></source>
<year>1957</year>
<volume>53</volume>
<page-range>217-219</page-range></nlm-citation>
</ref>
<ref id="B24">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Walton]]></surname>
<given-names><![CDATA[K.]]></given-names>
</name>
<name>
<surname><![CDATA[Marshall]]></surname>
<given-names><![CDATA[J. E.]]></given-names>
</name>
</person-group>
<article-title xml:lang="en"><![CDATA[Direct method for TDS stability analysis]]></article-title>
<source><![CDATA[IEE Proceedings on Control Theory Applications]]></source>
<year>1987</year>
<volume>134</volume>
<page-range>101-107</page-range></nlm-citation>
</ref>
</ref-list>
</back>
</article>
