<?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>0187-5779</journal-id>
<journal-title><![CDATA[Terra Latinoamericana]]></journal-title>
<abbrev-journal-title><![CDATA[Terra Latinoam]]></abbrev-journal-title>
<issn>0187-5779</issn>
<publisher>
<publisher-name><![CDATA[Sociedad Mexicana de la Ciencia del Suelo A.C.]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S0187-57792012000300279</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Configuración de herramientas de labranza vertical para reducir demanda de energía]]></article-title>
<article-title xml:lang="en"><![CDATA[Configuration of vertical tillage tools to reduce energy demand]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Cadena Zapata]]></surname>
<given-names><![CDATA[Martín]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Campos Magaña]]></surname>
<given-names><![CDATA[Santos Gabriel]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[López Santos]]></surname>
<given-names><![CDATA[Armando]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Zermeño González]]></surname>
<given-names><![CDATA[Alejandro]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Universidad Autónoma Agraria Antonio Narro División de Ingeniería ]]></institution>
<addr-line><![CDATA[Saltillo Coahuila]]></addr-line>
<country>Mexico</country>
</aff>
<aff id="Af2">
<institution><![CDATA[,Universidad Autónoma Chapingo URUZA ]]></institution>
<addr-line><![CDATA[Bermejillo Durango]]></addr-line>
<country>Mexico</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>09</month>
<year>2012</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>09</month>
<year>2012</year>
</pub-date>
<volume>30</volume>
<numero>3</numero>
<fpage>279</fpage>
<lpage>288</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S0187-57792012000300279&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S0187-57792012000300279&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S0187-57792012000300279&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen: Disminuir la demanda de energía en operaciones de labranza puede contribuir a la reducción de costos y a tener un menor uso de combustibles fósiles en los sistemas de producción. Lo anterior es posible si se establecen adecuadas interacciones entre geometría de implementos, configuraciones o arreglos de posiciones entre los mismos, profundidades de trabajo y humedad en el perfil. Se establecieron experimentos bajo un diseño estadístico de bloques al azar con tres repeticiones para evaluar: seis configuraciones de herramientas de labranza vertical tipo cincel, cuantificar la energía aplicada, demanda de fuerza de tiro y caracterizar la calidad de la labor. Para este propósito se construyó un equipo que permitió realizar dichos arreglos; se utilizó un dinamómetro axial y un transductor de tipo integral para reducir errores en el seguimiento y registro de variables. Se acondicionó la cabina del tractor para adaptar la instrumentación de adquisición de datos. Se midieron las variables: fuerza de tiro requerida (kN), sección transversal disturbada (m2), consumo de combustible (L ha-1), calidad de labor en términos de tamaño medio de agregados (mm) y resistencia específica del suelo (kN m-2). Los resultados mostraron diferencias significativas (Tukey, P &#8804; 0.05) entre los tratamientos respecto a calidad de trabajo y consumo de energía. Considerando ambas variables, en relación al de referencia, el mejor arreglo fue el de cinceles delanteros a 0.30 m de profundidad y 0.60 m de distancia entre ellos combinados con un cincel trasero a 0.40 m de profundidad, con lo anterior la demanda de energía se redujo 10.50% comparado con la configuración convencional. La calidad de trabajo, en relación a la referencia, produjo una reducción de tamaño de agregados de 28%, con el arreglo de cincel trasero alado profundo y cinceles frontales someros.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract: Reducing the demand of energy from tillage operations could contribute to decreasing production costs and use of fossil fuels in crop production systems; this can be made possible by establishing adequate interactions between implement geometry, configuration of components, working depth and soil moisture content. In this study, a field experiment was established under a statistical design of random blocks in order to evaluate six basic configurations of vertical tillage tine tools, to quantify applied energy and draught demand and to assess the quality of the operation. To achieve that, a frame was constructed that permits different layouts of tools; an axial and integral type force transducer was used to avoid error when recording and monitoring the variables. The tractor cabin was modified to adapt the instrumentation and data acquisition equipment. Three replications were carried out for each treatment measuring the draught force (kN), disturbed cross section (m2), fuel consumption (L ha-1) quality of operation in terms of medium diameter of aggregates (mm) and specific soil resistance (kN m-2). The results show significant differences (Tukey, P &#8804; 0.05) between treatments in relation to work quality and energy demand, considering both variables, relative to the reference, the best layout was shallow chisel tines at the front at 0.30 m working depth and 0.60 m apart, combined with a rear tine working at 0.40m depth, obtaining a reduction of energy of 10.50%. Considering just work quality in terms of aggregate size, a reduction of 28% was obtained with the layout of shallow tines at the front and a deep winged rear tine.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[evaluación de implementos]]></kwd>
<kwd lng="es"><![CDATA[consumo de combustible]]></kwd>
<kwd lng="es"><![CDATA[resistencia específica del suelo]]></kwd>
<kwd lng="es"><![CDATA[tamaño de agregados]]></kwd>
<kwd lng="en"><![CDATA[implement evaluation]]></kwd>
<kwd lng="en"><![CDATA[fuel consumption]]></kwd>
<kwd lng="en"><![CDATA[soil specific strength]]></kwd>
<kwd lng="en"><![CDATA[size of soil aggregates]]></kwd>
</kwd-group>
</article-meta>
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