<?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>0185-1101</journal-id>
<journal-title><![CDATA[Revista mexicana de astronomía y astrofísica]]></journal-title>
<abbrev-journal-title><![CDATA[Rev. mex. astron. astrofis]]></abbrev-journal-title>
<issn>0185-1101</issn>
<publisher>
<publisher-name><![CDATA[Universidad Nacional Autónoma de México, Instituto de Astronomía]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S0185-11012024000200343</article-id>
<article-id pub-id-type="doi">10.22201/ia.01851101p.2024.60.02.11</article-id>
<title-group>
<article-title xml:lang="en"><![CDATA[Feed-forward neural networks to estimate stokes profiles]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Raygoza-Romero]]></surname>
<given-names><![CDATA[Joan Manuel]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Lopez Nava]]></surname>
<given-names><![CDATA[Irvin Hussein]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Ramírez-Vélez]]></surname>
<given-names><![CDATA[Julio Cesar]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Centro de Investigación Científica y Educación Superior de Ensenada Departamento de Ciencias de la Computación ]]></institution>
<addr-line><![CDATA[Ensenada Baja California]]></addr-line>
<country>México</country>
</aff>
<aff id="Af2">
<institution><![CDATA[,Universidad Nacional Autónoma de México Instituto de Astronomía ]]></institution>
<addr-line><![CDATA[Ensenada Baja California]]></addr-line>
<country>Mexico</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>00</month>
<year>2024</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>00</month>
<year>2024</year>
</pub-date>
<volume>60</volume>
<numero>2</numero>
<fpage>343</fpage>
<lpage>354</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S0185-11012024000200343&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S0185-11012024000200343&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S0185-11012024000200343&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract Magnetic fields are believed to play a crucial role in stellar evolution. To better understand this evolution, it is essential to measure the magnetic fields on the stellar surface. These measurements can be achieved through spectropolarimetric observations, using the polarized radiative transfer equation. Magnetic field properties are inferred by adjusting the Stokes profiles. In this study, we propose a deep learning approach using a feed-forward neural network to estimate the Stokes profiles based on eight input parameters that describe the magnetic field configuration. To achieve this, we conducted scaling experiments on the data, explored di&#64256;erent configurations of the FNN architecture, and compared two approaches. A model capable of accurately estimating the Stokes profiles I, Q and V was obtained. However, we encountered di&#64259;culties in estimating Stokes profiles Q and U when they have low amplitudes.]]></p></abstract>
<abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen Los campos magnéticos desempeñan un papel crucial en la evolución estelar. Para comprender mejor esta evolución, es esencial medirlos en la superficie estelar. Estas mediciones se logran mediante observaciones espectropolarimétricas, utilizando la ecuación de transferencia radiativa polarizada. Las propiedades del campo magnético se infieren ajustando los perfiles de Stokes. Este estudio propone un enfoque de aprendizaje profundo mediante una red neuronal feed-forward para estimar los perfiles de Stokes a partir de ocho parámetros que describen la configuración del campo magnético. Se realizaron experimentos de escalado, de diversas configuraciones de la arquitectura y se compararon dos enfoques. Se obtuvo un modelo que logra una estimación precisa de los perfiles de Stokes I, Q y V. Sin embargo, hubo dificultades para estimar los perfiles de Stokes Q y U cuando estos tienen una amplitud baja.]]></p></abstract>
<kwd-group>
<kwd lng="en"><![CDATA[methods: data analysis]]></kwd>
<kwd lng="en"><![CDATA[polarization]]></kwd>
<kwd lng="en"><![CDATA[stars: magnetic field]]></kwd>
</kwd-group>
</article-meta>
</front><back>
<ref-list>
<ref id="B1">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Asensio]]></surname>
<given-names><![CDATA[A.]]></given-names>
</name>
<name>
<surname><![CDATA[Díaz]]></surname>
<given-names><![CDATA[C. J.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Stokes inversion based on convolutional neural networks]]></article-title>
<source><![CDATA[A&amp;A]]></source>
<year>2019</year>
<volume>626</volume>
<page-range>102</page-range></nlm-citation>
</ref>
<ref id="B2">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Carroll]]></surname>
<given-names><![CDATA[T. A.]]></given-names>
</name>
<name>
<surname><![CDATA[Kopf]]></surname>
<given-names><![CDATA[M.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Zeeman-tomography of the solar photosphere. Three-dimensional surface structures retrieved from Hinode observations]]></article-title>
<source><![CDATA[A&amp;A]]></source>
<year>2008</year>
<volume>481</volume>
<page-range>37</page-range></nlm-citation>
</ref>
<ref id="B3">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Carroll]]></surname>
<given-names><![CDATA[T. A.]]></given-names>
</name>
<name>
<surname><![CDATA[Kopf]]></surname>
<given-names><![CDATA[M.]]></given-names>
</name>
<name>
<surname><![CDATA[Strassmeier]]></surname>
<given-names><![CDATA[K. G.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[A fast method for Stokes profile synthesis. Radiative transfer modeling for ZDI and Stokes profile inversion]]></article-title>
<source><![CDATA[A&amp;A]]></source>
<year>2008</year>
<volume>488</volume>
<page-range>781</page-range></nlm-citation>
</ref>
<ref id="B4">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Carroll]]></surname>
<given-names><![CDATA[T. A.]]></given-names>
</name>
<name>
<surname><![CDATA[Staude]]></surname>
<given-names><![CDATA[J.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[The inversion of Stokes profiles with artificial neural networks]]></article-title>
<source><![CDATA[A&amp;A]]></source>
<year>2001</year>
<volume>378</volume>
<page-range>316</page-range></nlm-citation>
</ref>
<ref id="B5">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Córdova]]></surname>
<given-names><![CDATA[J. P.]]></given-names>
</name>
<name>
<surname><![CDATA[Navarro]]></surname>
<given-names><![CDATA[S. G.]]></given-names>
</name>
<name>
<surname><![CDATA[Ramírez-Vélez]]></surname>
<given-names><![CDATA[J. C.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Machine Learning for Stellar Magnetic Field Determination]]></article-title>
<source><![CDATA[International Journal of Computational Intelligence Systems]]></source>
<year>2018</year>
<volume>11</volume>
<page-range>608</page-range></nlm-citation>
</ref>
<ref id="B6">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Degl&#8217;Innocenti]]></surname>
<given-names><![CDATA[M. L.]]></given-names>
</name>
<name>
<surname><![CDATA[Landolfi]]></surname>
<given-names><![CDATA[M.]]></given-names>
</name>
</person-group>
<source><![CDATA[Polarization in spectral lines]]></source>
<year>2006</year>
<volume>307</volume>
<publisher-name><![CDATA[Springer Science &amp; Business Media]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B7">
<nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[del Toro Iniesta]]></surname>
<given-names><![CDATA[J. C.]]></given-names>
</name>
</person-group>
<source><![CDATA[Introduction to spectropolarimetry]]></source>
<year>2003</year>
</nlm-citation>
</ref>
<ref id="B8">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Gafeira]]></surname>
<given-names><![CDATA[R.]]></given-names>
</name>
<name>
<surname><![CDATA[Orozco]]></surname>
<given-names><![CDATA[D.]]></given-names>
</name>
<name>
<surname><![CDATA[Mili&#263;]]></surname>
<given-names><![CDATA[I.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Machine learning initialization to accelerate Stokes profile inversions]]></article-title>
<source><![CDATA[A&amp;A]]></source>
<year>2021</year>
<volume>651</volume>
<page-range>31</page-range></nlm-citation>
</ref>
<ref id="B9">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Knyazeva]]></surname>
<given-names><![CDATA[I.]]></given-names>
</name>
<name>
<surname><![CDATA[Plotnikov]]></surname>
<given-names><![CDATA[A.]]></given-names>
</name>
<name>
<surname><![CDATA[Medvedeva]]></surname>
<given-names><![CDATA[T.]]></given-names>
</name>
<name>
<surname><![CDATA[Makarenko]]></surname>
<given-names><![CDATA[N.]]></given-names>
</name>
<name>
<surname><![CDATA[Kryzhanovsky]]></surname>
<given-names><![CDATA[B.]]></given-names>
</name>
<name>
<surname><![CDATA[Dunin-Barkowski]]></surname>
<given-names><![CDATA[W.]]></given-names>
</name>
<name>
<surname><![CDATA[Redko]]></surname>
<given-names><![CDATA[V.]]></given-names>
</name>
<name>
<surname><![CDATA[Tiumentsev]]></surname>
<given-names><![CDATA[Y.]]></given-names>
</name>
<name>
<surname><![CDATA[Klimov]]></surname>
<given-names><![CDATA[V. V.]]></given-names>
</name>
</person-group>
<source><![CDATA[Advances in Neural Computation, Machine Learning, and Cognitive Research V]]></source>
<year>2021</year>
<page-range>299</page-range><publisher-name><![CDATA[Springer, Cham]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B10">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Paliwal]]></surname>
<given-names><![CDATA[M.]]></given-names>
</name>
<name>
<surname><![CDATA[Kumar]]></surname>
<given-names><![CDATA[U. A.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Neural networks and statistical techniques: A review of applications]]></article-title>
<source><![CDATA[Expert systems with applications]]></source>
<year>2009</year>
<volume>36</volume>
<page-range>2</page-range></nlm-citation>
</ref>
<ref id="B11">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Ramírez-Vélez]]></surname>
<given-names><![CDATA[J. C.]]></given-names>
</name>
<name>
<surname><![CDATA[Yáñez]]></surname>
<given-names><![CDATA[C.]]></given-names>
</name>
<name>
<surname><![CDATA[Córdova]]></surname>
<given-names><![CDATA[J. P.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Using machine learning algorithms to measure stellar magnetic fields]]></article-title>
<source><![CDATA[A&amp;A]]></source>
<year>2018</year>
<volume>619</volume>
<page-range>22</page-range></nlm-citation>
</ref>
<ref id="B12">
<nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Smith]]></surname>
<given-names><![CDATA[L. N.]]></given-names>
</name>
</person-group>
<source><![CDATA[A disciplined approach to neural network hyper-parameters]]></source>
<year>2018</year>
</nlm-citation>
</ref>
<ref id="B13">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Stift]]></surname>
<given-names><![CDATA[M. J.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[A Non-Axisymmetric Rigid Rotator Model for Magnetic Stars]]></article-title>
<source><![CDATA[MNRAS]]></source>
<year>1975</year>
<volume>172</volume>
<page-range>133</page-range></nlm-citation>
</ref>
<ref id="B14">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Stift]]></surname>
<given-names><![CDATA[M. J.]]></given-names>
</name>
<name>
<surname><![CDATA[Leone]]></surname>
<given-names><![CDATA[F.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Magnetic intensification of spectral lines]]></article-title>
<source><![CDATA[A&amp;A]]></source>
<year>2003</year>
<volume>388</volume>
<page-range>411</page-range></nlm-citation>
</ref>
<ref id="B15">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Svozil]]></surname>
<given-names><![CDATA[D.]]></given-names>
</name>
<name>
<surname><![CDATA[Kvasnicka]]></surname>
<given-names><![CDATA[V.]]></given-names>
</name>
<name>
<surname><![CDATA[Pospichal]]></surname>
<given-names><![CDATA[J.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Introduction to multi-layer feed-forward neural networks]]></article-title>
<source><![CDATA[Chemometrics and Intelligent Laboratory Systems]]></source>
<year>1997</year>
<volume>39</volume>
<page-range>43</page-range></nlm-citation>
</ref>
<ref id="B16">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Zhuang]]></surname>
<given-names><![CDATA[F.]]></given-names>
</name>
<name>
<surname><![CDATA[Qi]]></surname>
<given-names><![CDATA[Z.]]></given-names>
</name>
<name>
<surname><![CDATA[Duan]]></surname>
<given-names><![CDATA[K.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[A Comprehensive Survey on Transfer Learning]]></article-title>
<source><![CDATA[Proceedings of the IEEE]]></source>
<year>2021</year>
<volume>109</volume>
<page-range>43</page-range></nlm-citation>
</ref>
</ref-list>
</back>
</article>
