<?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>2071-0054</journal-id>
<journal-title><![CDATA[Revista Ciencias Técnicas Agropecuarias]]></journal-title>
<abbrev-journal-title><![CDATA[Rev Cie Téc Agr]]></abbrev-journal-title>
<issn>2071-0054</issn>
<publisher>
<publisher-name><![CDATA[Universidad Agraria de La Habana]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S2071-00542021000200003</article-id>
<title-group>
<article-title xml:lang="en"><![CDATA[Effect of Vibrations and Operational Parameters in Frequency and Amplitude of a Vibratory Subsoiler]]></article-title>
<article-title xml:lang="es"><![CDATA[Efecto de las vibraciones y parámetros de operación en la frecuencia y amplitud de un subsolador vibratorio]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Marín-Cabrera]]></surname>
<given-names><![CDATA[Luis Orlando]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[García de la Figal-Costales]]></surname>
<given-names><![CDATA[Armando Eloy]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Martínez-Rodríguez]]></surname>
<given-names><![CDATA[Arturo]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Universidad Agraria de La Habana (UNAH) Facultad de Ciencias Técnicas Centro de Mecanización Agropecuaria (CEMA)]]></institution>
<addr-line><![CDATA[San José de las Lajas Mayabeque]]></addr-line>
<country>Cuba</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>06</month>
<year>2021</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>06</month>
<year>2021</year>
</pub-date>
<volume>30</volume>
<numero>2</numero>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://scielo.sld.cu/scielo.php?script=sci_arttext&amp;pid=S2071-00542021000200003&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://scielo.sld.cu/scielo.php?script=sci_abstract&amp;pid=S2071-00542021000200003&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://scielo.sld.cu/scielo.php?script=sci_pdf&amp;pid=S2071-00542021000200003&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="en"><p><![CDATA[ABSTRACT This paper aims to analyze the effect of free and forced vibrations and of working depth on the frequency and amplitude of a vibratory curved bent leg subsoiler plowing a silt loam soil (Rhodic Ferralsol) by the modal analysis of the soil-bent leg system. The finite elements method and the design software Solid Works with its complement Simulation were used to model and to simulate, the bent leg scarifier­ soil interaction. The soil was considered as homogeneous and elastoplastic of Drucker-Prager extended constitutive relation. The results showed the significant effect of the work depth on the frequencies and amplitude of the soil when the vibratory system works with free vibrations. When forced vibrations were used to different work depths, significant differences were not observed in frequencies neither of the bent leg nor of the soil. On the other hand, the resonant frequencies of the shank obtained corresponding to the two first vibration modes (2,20; 8,47 and 13,35 Hz) at a working depth of 200 mm allowed a better loosening of the soil.]]></p></abstract>
<abstract abstract-type="short" xml:lang="es"><p><![CDATA[RESUMEN Para analizar el efecto de las vibraciones libres y forzadas y la profundidad de trabajo en la frecuencia y amplitud de las vibraciones de una herramienta de labranza (subsolador vibratorio de brazo curvo) cultivando un suelo arcilloso limoso (Rhodic Ferralsol) mediante un análisis modal del sistema brazo-suelo, se simuló la interacción suelo-herramienta de labranza, mediante el método de elementos finitos y el software de diseño Solid Works, con su complemento Simulation, considerando el suelo homogéneo y elastoplástico de relación constitutiva Drucker-Prager Extendido. Los resultados mostraron el efecto significativo de la profundidad de trabajo en las frecuencias y amplitud del suelo cuando el sistema vibratorio trabaja con vibraciones libres, mientras que con vibraciones forzadas no se observaron diferencias significativas en las frecuencias tanto del brazo como del suelo. Por otra parte, las frecuencias resonantes del brazo obtenidas correspondientes a los dos primeros modos de vibración (2,20; 8,47 y 13,35 Hz) a una profundidad de operación de 200 mm permiten un mejor aflojamiento del suelo.]]></p></abstract>
<kwd-group>
<kwd lng="en"><![CDATA[Subsoiler]]></kwd>
<kwd lng="en"><![CDATA[Free Vibrations]]></kwd>
<kwd lng="en"><![CDATA[Forced Vibrations]]></kwd>
<kwd lng="en"><![CDATA[Working Depth]]></kwd>
<kwd lng="es"><![CDATA[subsolador]]></kwd>
<kwd lng="es"><![CDATA[vibraciones libres]]></kwd>
<kwd lng="es"><![CDATA[vibraciones forzadas]]></kwd>
<kwd lng="es"><![CDATA[profundidad de trabajo]]></kwd>
</kwd-group>
</article-meta>
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