<?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>S1665-64232021000300263</article-id>
<article-id pub-id-type="doi">10.22201/icat.24486736e.2021.19.3.1697</article-id>
<title-group>
<article-title xml:lang="en"><![CDATA[Real-time implementation of QFT, GA, and BFTPSO controller for pH neutralization system]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Aparna]]></surname>
<given-names><![CDATA[V.]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Jamal]]></surname>
<given-names><![CDATA[D. N.]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,B. S. Abdur Rahman Crescent Institute of Science &amp; Technology Department of Electronics and Instrumentation Engineering ]]></institution>
<addr-line><![CDATA[Chennai ]]></addr-line>
<country>India</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>00</month>
<year>2021</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>00</month>
<year>2021</year>
</pub-date>
<volume>19</volume>
<numero>3</numero>
<fpage>263</fpage>
<lpage>278</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S1665-64232021000300263&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S1665-64232021000300263&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S1665-64232021000300263&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract The control of a pH process is complex because of severe nonlinearities in its behavior. A continuous pH neutralization process is usually represented as a first-order plus dead time system, but its gain varies for different operating points. Therefore, a conventional linear controller cannot be used, and the pH system was thus represented as a linear state-space model around an equilibrium point. This linear model was then used to compute the PID controller gains using robust and optimization techniques like quantitative feedback theory, bacterial foraging technique-based particle swarm optimization algorithm, and genetic algorithm. The corresponding controller gains resulting from the three algorithms were used to control the pH using a reconfigurable I/O device, NI myRIO-1900. Finally, the output time domain specifications and the servo and regulatory responses, resulting from the three algorithms, were compared in simulation and in real-time to deduce the appropriate tuning algorithm for this system.]]></p></abstract>
<kwd-group>
<kwd lng="en"><![CDATA[pH Control]]></kwd>
<kwd lng="en"><![CDATA[PID Controller]]></kwd>
<kwd lng="en"><![CDATA[Genetic Algorithm]]></kwd>
<kwd lng="en"><![CDATA[Hybrid Bacterial Foraging Technique Particle Swarm Optimization]]></kwd>
<kwd lng="en"><![CDATA[Quantitative Feedback Theory]]></kwd>
<kwd lng="en"><![CDATA[Robust Control]]></kwd>
</kwd-group>
</article-meta>
</front><back>
<ref-list>
<ref id="B1">
<nlm-citation citation-type="confpro">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Abdullah]]></surname>
<given-names><![CDATA[N. H. S.]]></given-names>
</name>
<name>
<surname><![CDATA[Karsiti]]></surname>
<given-names><![CDATA[M. N.]]></given-names>
</name>
<name>
<surname><![CDATA[Ibrahim]]></surname>
<given-names><![CDATA[R.]]></given-names>
</name>
</person-group>
<source><![CDATA[A review of pH neutralization process control]]></source>
<year>2012</year>
<volume>2</volume>
<conf-name><![CDATA[ 4thInternational Conference on Intelligent and Advanced Systems]]></conf-name>
<conf-date>2012</conf-date>
<conf-loc> </conf-loc>
<page-range>594-8</page-range></nlm-citation>
</ref>
<ref id="B2">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Ali]]></surname>
<given-names><![CDATA[E.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[pH Control Using PI Control Algorithms with Automatic Tuning Method]]></article-title>
<source><![CDATA[Chemical Engineering Research and Design]]></source>
<year>2001</year>
<volume>79</volume>
<numero>5</numero>
<issue>5</issue>
<page-range>611-20</page-range></nlm-citation>
</ref>
<ref id="B3">
<nlm-citation citation-type="confpro">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Alina]]></surname>
<given-names><![CDATA[B.]]></given-names>
</name>
<name>
<surname><![CDATA[M&#259;d&#259;lina]]></surname>
<given-names><![CDATA[C.]]></given-names>
</name>
</person-group>
<source><![CDATA[Internal model control for wastewater ph neutralization process]]></source>
<year>2016</year>
<conf-name><![CDATA[ 8thInternational Conference on Electronics, Computers and Artificial Intelligence]]></conf-name>
<conf-loc> </conf-loc>
<page-range>1-6</page-range><publisher-name><![CDATA[IEEE]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B4">
<nlm-citation citation-type="confpro">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Aparna]]></surname>
<given-names><![CDATA[V.]]></given-names>
</name>
</person-group>
<source><![CDATA[Development of automated pH monitoring &amp; control system through USB Data Acquisition]]></source>
<year>2014</year>
<conf-name><![CDATA[ 6thIEEE Power India International Conference]]></conf-name>
<conf-date>2014</conf-date>
<conf-loc> </conf-loc>
<page-range>1-6</page-range></nlm-citation>
</ref>
<ref id="B5">
<nlm-citation citation-type="confpro">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Aparna]]></surname>
<given-names><![CDATA[V.]]></given-names>
</name>
<name>
<surname><![CDATA[Banu]]></surname>
<given-names><![CDATA[U. S.]]></given-names>
</name>
<name>
<surname><![CDATA[Yasmin]]></surname>
<given-names><![CDATA[S.]]></given-names>
</name>
</person-group>
<source><![CDATA[PI controller design using quantitative feedback theory for a flow process]]></source>
<year>2017</year>
<conf-name><![CDATA[ IEEE International Conference on Technological Innovations in Communication, Control and Automation]]></conf-name>
<conf-date>2017</conf-date>
<conf-loc> </conf-loc>
</nlm-citation>
</ref>
<ref id="B6">
<nlm-citation citation-type="confpro">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Barve]]></surname>
<given-names><![CDATA[J. J.]]></given-names>
</name>
<name>
<surname><![CDATA[Nataraj]]></surname>
<given-names><![CDATA[P. S. V.]]></given-names>
</name>
</person-group>
<source><![CDATA[Synthesis of a robust pH controller using QFT]]></source>
<year>1999</year>
<volume>1</volume>
<conf-name><![CDATA[ 10International Conference on Global Connectivity in Energy, Computer, Communication and Control]]></conf-name>
<conf-loc> </conf-loc>
<page-range>214-7</page-range></nlm-citation>
</ref>
<ref id="B7">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Bequette]]></surname>
<given-names><![CDATA[B. W.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Nonlinear control of chemical processes: a review]]></article-title>
<source><![CDATA[Industrial &amp; Engineering Chemistry Research]]></source>
<year>1991</year>
<volume>30</volume>
<numero>7</numero>
<issue>7</issue>
<page-range>1391-413</page-range></nlm-citation>
</ref>
<ref id="B8">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Bharathi]]></surname>
<given-names><![CDATA[N.]]></given-names>
</name>
<name>
<surname><![CDATA[Shanmugam]]></surname>
<given-names><![CDATA[J.]]></given-names>
</name>
<name>
<surname><![CDATA[Rangaswamy]]></surname>
<given-names><![CDATA[T. R.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Intelligent Control of pH in a Neutralization Process]]></article-title>
<source><![CDATA[Asian Journal of Information Technology]]></source>
<year>2007</year>
<volume>6</volume>
<numero>6</numero>
<issue>6</issue>
<page-range>667-73</page-range></nlm-citation>
</ref>
<ref id="B9">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Biagiola]]></surname>
<given-names><![CDATA[S. I.]]></given-names>
</name>
<name>
<surname><![CDATA[Agamennoni]]></surname>
<given-names><![CDATA[O. E.]]></given-names>
</name>
<name>
<surname><![CDATA[Figueroa]]></surname>
<given-names><![CDATA[J. L.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Robust control of wiener systems: application to a ph neutralization process]]></article-title>
<source><![CDATA[Brazilian Journal of Chemical Engineering]]></source>
<year>2016</year>
<volume>33</volume>
<numero>1</numero>
<issue>1</issue>
<page-range>145-53</page-range></nlm-citation>
</ref>
<ref id="B10">
<nlm-citation citation-type="confpro">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Bingi]]></surname>
<given-names><![CDATA[K.]]></given-names>
</name>
<name>
<surname><![CDATA[Ibrahim]]></surname>
<given-names><![CDATA[R.]]></given-names>
</name>
<name>
<surname><![CDATA[Karsiti]]></surname>
<given-names><![CDATA[M. N.]]></given-names>
</name>
<name>
<surname><![CDATA[Chung]]></surname>
<given-names><![CDATA[T. D.]]></given-names>
</name>
<name>
<surname><![CDATA[Hassan]]></surname>
<given-names><![CDATA[S. M.]]></given-names>
</name>
</person-group>
<source><![CDATA[Optimal PID control of pH neutralization plant]]></source>
<year>2016</year>
<conf-name><![CDATA[ 2ndIEEE International Symposium on Robotics and Manufacturing Automation]]></conf-name>
<conf-date>2016</conf-date>
<conf-loc>ROMA </conf-loc>
<page-range>1-6</page-range></nlm-citation>
</ref>
<ref id="B11">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Bingi]]></surname>
<given-names><![CDATA[K.]]></given-names>
</name>
<name>
<surname><![CDATA[Ibrahim]]></surname>
<given-names><![CDATA[R.]]></given-names>
</name>
<name>
<surname><![CDATA[Karsiti]]></surname>
<given-names><![CDATA[M. N.]]></given-names>
</name>
<name>
<surname><![CDATA[Hassan]]></surname>
<given-names><![CDATA[S. M.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Fractional Order Set-point Weighted PID Controller for pH Neutralization Process Using Accelerated PSO Algorithm]]></article-title>
<source><![CDATA[Arabian Journal for Science and Engineering]]></source>
<year>2018</year>
<volume>43</volume>
<numero>6</numero>
<issue>6</issue>
<page-range>2687-701</page-range></nlm-citation>
</ref>
<ref id="B12">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Bingi]]></surname>
<given-names><![CDATA[K.]]></given-names>
</name>
<name>
<surname><![CDATA[Ibrahim]]></surname>
<given-names><![CDATA[R.]]></given-names>
</name>
<name>
<surname><![CDATA[Karsiti]]></surname>
<given-names><![CDATA[M. N.]]></given-names>
</name>
<name>
<surname><![CDATA[Hassan]]></surname>
<given-names><![CDATA[S. M.]]></given-names>
</name>
<name>
<surname><![CDATA[Harindran]]></surname>
<given-names><![CDATA[V. R.]]></given-names>
</name>
</person-group>
<source><![CDATA[Fractional-order Systems and PID Controllers]]></source>
<year>2020</year>
<publisher-name><![CDATA[Springer International Publishing]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B13">
<nlm-citation citation-type="confpro">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Darab]]></surname>
<given-names><![CDATA[C.]]></given-names>
</name>
<name>
<surname><![CDATA[Hodrea]]></surname>
<given-names><![CDATA[R.]]></given-names>
</name>
<name>
<surname><![CDATA[Crisan]]></surname>
<given-names><![CDATA[R.]]></given-names>
</name>
<name>
<surname><![CDATA[Nascu]]></surname>
<given-names><![CDATA[I.]]></given-names>
</name>
</person-group>
<source><![CDATA[Modeling and internal model control strategy of pH neutralization process]]></source>
<year>2012</year>
<conf-name><![CDATA[ 20thTelecommunications Forum]]></conf-name>
<conf-date>2012</conf-date>
<conf-loc> </conf-loc>
<page-range>1579-82</page-range></nlm-citation>
</ref>
<ref id="B14">
<nlm-citation citation-type="confpro">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Dixit]]></surname>
<given-names><![CDATA[S. A.]]></given-names>
</name>
<name>
<surname><![CDATA[Jain]]></surname>
<given-names><![CDATA[A.]]></given-names>
</name>
</person-group>
<source><![CDATA[Implementation of PPC-SSR as final control element and interfacing of PLC with LabVIEW using Modbus in two tank non interacting level control system]]></source>
<year>2016</year>
<conf-name><![CDATA[ 1stInternational Conference on Power Electronics, Intelligent Control and Energy Systems]]></conf-name>
<conf-date>2016</conf-date>
<conf-loc> </conf-loc>
<page-range>1-6</page-range></nlm-citation>
</ref>
<ref id="B15">
<nlm-citation citation-type="confpro">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Elameen]]></surname>
<given-names><![CDATA[M. H. E.]]></given-names>
</name>
<name>
<surname><![CDATA[Karsiti]]></surname>
<given-names><![CDATA[M. N.]]></given-names>
</name>
<name>
<surname><![CDATA[Ibrahim]]></surname>
<given-names><![CDATA[R.]]></given-names>
</name>
</person-group>
<source><![CDATA[Nonlinear model feedback linearization control strategy of a pH neutralization process]]></source>
<year>2014</year>
<volume>1</volume>
<conf-name><![CDATA[ 5thInternational Conference on Intelligent and Advanced Systems]]></conf-name>
<conf-date>2014</conf-date>
<conf-loc> </conf-loc>
<page-range>1-5</page-range></nlm-citation>
</ref>
<ref id="B16">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Faanes]]></surname>
<given-names><![CDATA[A.]]></given-names>
</name>
<name>
<surname><![CDATA[Skogestad]]></surname>
<given-names><![CDATA[S.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[pH-neutralization: integrated process and control design]]></article-title>
<source><![CDATA[Computers &amp; Chemical Engineering]]></source>
<year>2004</year>
<volume>28</volume>
<numero>8</numero>
<issue>8</issue>
<page-range>1475-87</page-range></nlm-citation>
</ref>
<ref id="B17">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Hassan]]></surname>
<given-names><![CDATA[S. M.]]></given-names>
</name>
<name>
<surname><![CDATA[Ibrahim]]></surname>
<given-names><![CDATA[R.]]></given-names>
</name>
<name>
<surname><![CDATA[Saad]]></surname>
<given-names><![CDATA[N.]]></given-names>
</name>
<name>
<surname><![CDATA[Bingi]]></surname>
<given-names><![CDATA[K.]]></given-names>
</name>
<name>
<surname><![CDATA[Asirvadam]]></surname>
<given-names><![CDATA[V. S.]]></given-names>
</name>
</person-group>
<source><![CDATA[Hybrid PID Based Predictive Control Strategies for WirelessHART Networked Control Systems]]></source>
<year>2020</year>
<volume>293</volume>
<publisher-name><![CDATA[Springer Nature]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B18">
<nlm-citation citation-type="confpro">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Ibrahim]]></surname>
<given-names><![CDATA[R.]]></given-names>
</name>
<name>
<surname><![CDATA[Murray-Smith]]></surname>
<given-names><![CDATA[D. J.]]></given-names>
</name>
</person-group>
<source><![CDATA[Design, implementation and performance evaluation of a fuzzy control system for a pH neutralisation process pilot plant]]></source>
<year>2007</year>
<conf-name><![CDATA[ International Conference on Intelligent and Advanced Systems]]></conf-name>
<conf-date>2007</conf-date>
<conf-loc> </conf-loc>
<page-range>1001-6</page-range></nlm-citation>
</ref>
<ref id="B19">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Ibrahim]]></surname>
<given-names><![CDATA[R.]]></given-names>
</name>
</person-group>
<source><![CDATA[Practical modelling and control implementation studies on a pH neutralization process pilot plant]]></source>
<year>2008</year>
<publisher-name><![CDATA[University of Glasgow]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B20">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Moore]]></surname>
<given-names><![CDATA[R. L.]]></given-names>
</name>
</person-group>
<source><![CDATA[Environmental Protection by the Neutralization of Wastewater Using PH Control]]></source>
<year>1995</year>
<publisher-name><![CDATA[Isa]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B21">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Shajahan]]></surname>
<given-names><![CDATA[M. M.]]></given-names>
</name>
<name>
<surname><![CDATA[Jamal]]></surname>
<given-names><![CDATA[D. N.]]></given-names>
</name>
<name>
<surname><![CDATA[Aparna]]></surname>
<given-names><![CDATA[V.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Controller design using quantitative feedback theory for thermal power plant process]]></article-title>
<source><![CDATA[Case studies in thermal engineering]]></source>
<year>2019</year>
<volume>14</volume>
</nlm-citation>
</ref>
<ref id="B22">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Shajahan]]></surname>
<given-names><![CDATA[M. M.]]></given-names>
</name>
<name>
<surname><![CDATA[Jamal]]></surname>
<given-names><![CDATA[D. N.]]></given-names>
</name>
<name>
<surname><![CDATA[Aparna]]></surname>
<given-names><![CDATA[V.]]></given-names>
</name>
<name>
<surname><![CDATA[Khan]]></surname>
<given-names><![CDATA[M. A.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Control of electric power generation of thermal power plant in TamilNadu]]></article-title>
<source><![CDATA[Case studies in thermal engineering]]></source>
<year>2018</year>
<volume>12</volume>
<page-range>728-35</page-range></nlm-citation>
</ref>
<ref id="B23">
<nlm-citation citation-type="confpro">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Rodriguez]]></surname>
<given-names><![CDATA[J. L.]]></given-names>
</name>
<name>
<surname><![CDATA[Loparo]]></surname>
<given-names><![CDATA[K. A.]]></given-names>
</name>
</person-group>
<source><![CDATA[Modeling and identification of pH processes]]></source>
<year>2004</year>
<volume>6</volume>
<conf-name><![CDATA[ American Control Conference]]></conf-name>
<conf-date>2004</conf-date>
<conf-loc> </conf-loc>
<page-range>5483-8</page-range></nlm-citation>
</ref>
<ref id="B24">
<nlm-citation citation-type="confpro">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Saji]]></surname>
<given-names><![CDATA[K. S.]]></given-names>
</name>
<name>
<surname><![CDATA[Sasi Kumar]]></surname>
<given-names><![CDATA[M.]]></given-names>
</name>
</person-group>
<source><![CDATA[A novel controller tuning of pH neutralization process]]></source>
<year>2011</year>
<conf-name><![CDATA[ International Conference on Signal Processing, Communication, Computing and Networking Technologies]]></conf-name>
<conf-date>2011</conf-date>
<conf-loc> </conf-loc>
<page-range>712-7</page-range></nlm-citation>
</ref>
<ref id="B25">
<nlm-citation citation-type="confpro">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Shabani]]></surname>
<given-names><![CDATA[R.]]></given-names>
</name>
<name>
<surname><![CDATA[Sedigh]]></surname>
<given-names><![CDATA[A. K.]]></given-names>
</name>
<name>
<surname><![CDATA[Salahshoor]]></surname>
<given-names><![CDATA[K.]]></given-names>
</name>
</person-group>
<source><![CDATA[Robust control of a pH neutralization process plant using QFT]]></source>
<year>2010</year>
<conf-name><![CDATA[ ICCAS]]></conf-name>
<conf-date>2010</conf-date>
<conf-loc> </conf-loc>
<page-range>497-500</page-range></nlm-citation>
</ref>
<ref id="B26">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Shinskey]]></surname>
<given-names><![CDATA[F. G.]]></given-names>
</name>
</person-group>
<source><![CDATA[pH and pION Control in Process and Waste Streams (Environmental Science &amp; Technology)]]></source>
<year>1973</year>
<publisher-name><![CDATA[Wiley]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B27">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Tadeo]]></surname>
<given-names><![CDATA[F.]]></given-names>
</name>
<name>
<surname><![CDATA[Lopez]]></surname>
<given-names><![CDATA[O. P.]]></given-names>
</name>
<name>
<surname><![CDATA[Alvarez]]></surname>
<given-names><![CDATA[T.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Control of neutralization processes by robust loop shaping]]></article-title>
<source><![CDATA[IEEE Transactions on Control Systems Technology]]></source>
<year>2000</year>
<volume>8</volume>
<numero>2</numero>
<issue>2</issue>
<page-range>236-46</page-range></nlm-citation>
</ref>
</ref-list>
</back>
</article>
