<?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>2007-4026</journal-id>
<journal-title><![CDATA[Ingeniería agrícola y biosistemas]]></journal-title>
<abbrev-journal-title><![CDATA[Ing. agric. biosist.]]></abbrev-journal-title>
<issn>2007-4026</issn>
<publisher>
<publisher-name><![CDATA[Universidad Autónoma Chapingo]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S2007-40262018000100003</article-id>
<article-id pub-id-type="doi">10.5154/r.inagbi.2017.01.002</article-id>
<title-group>
<article-title xml:lang="en"><![CDATA[Determination of shear velocity in a mild-sloping open channel flow]]></article-title>
<article-title xml:lang="es"><![CDATA[Determinación de la velocidad de corte en un flujo de canal abierto de baja pendiente]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Mendoza-González]]></surname>
<given-names><![CDATA[Ángel]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Aguilar-Chávez]]></surname>
<given-names><![CDATA[Ariosto]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Instituto Mexicano de Tecnología del Agua  ]]></institution>
<addr-line><![CDATA[Jiutepec Morelos]]></addr-line>
<country>Mexico</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>06</month>
<year>2018</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>06</month>
<year>2018</year>
</pub-date>
<volume>10</volume>
<numero>1</numero>
<fpage>3</fpage>
<lpage>12</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S2007-40262018000100003&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S2007-40262018000100003&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S2007-40262018000100003&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract  Objective:  To present a methodology that allows experimentally determining shear velocity, considering the log-law as a model of velocity distribution in the outer region of turbulent flow.  Mathodology: The experimental study was carried out in a rectangular-shaped, variably-sloped channel with a 0.245-m-wide base and 5 m long. Flow velocity was measured with an Acoustic Doppler Velocimeter (ADV), and the measurement area was 12 mm. Shear velocity was determined by the instantaneous velocity equation (   u  i , j).  Results:  The log-law model had a good statistical fit with the shear velocity estimated from the experimental data.  Study limitations: The experimental tests were conducted only in subcritical regime with low aspect ratios. In addition, in all tests, the measurement of instantaneous velocities was carried out only in a 12-mm profile, as close as possible to the wall.  Originality: The model to calculate the shear velocity is presented explicitly, and the statistical approach employed supports the use of the median as an estimator of the shear velocity.  Conclusions:  The presented methodology shows low uncertainty in the estimation of shear velocity. The Anderson-Darling test showed that the results do not follow a normal distribution, so the median is the statistical parameter to define the shear velocity value.]]></p></abstract>
<abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen  Objetivo:  Presentar una metodología que permita determinar en forma experimental la velocidad de corte, considerando la ley logarítmica como modelo de distribución de velocidad en la región exterior de flujo turbulento.  Metodología:  El estudio experimental se realizó en un canal de pendiente variable de sección rectangular, 0.245 m de base y 5 m de longitud. La velocidad del flujo se midió con un acoustic Doppler velocimeter (ADV), y la zona de medición fue de 12 mm. La velocidad de corte se determinó mediante la ecuación de la velocidad instantánea (   u  i , j).  Resultados:  El modelo de la ley logarítmica tuvo un buen ajuste estadístico con la velocidad de corte estimada a partir de los datos experimentales.  Limitaciones del estudio: Las pruebas experimentales se desarrollaron únicamente en régimen subcrítico con bajas relaciones de aspecto. Además, en todas las pruebas, la medición de las velocidades instantáneas se llevó a cabo solo en un perfil de 12 mm, lo más cercano posible a la pared.  Originalidad: El modelo para calcular la velocidad de corte se presente explícitamente, y el enfoque estadístico empleado sustenta el uso de la mediana como estimador de la velocidad de corte.  Conclusiones:  La metodología presentada muestra baja incertidumbre en la estimación de la velocidad de corte. La prueba de Anderson-Darling permitió demostrar que los resultados no siguen una distribución normal, por lo que la mediana es el parámetro estadístico para definir el valor de la velocidad de corte.]]></p></abstract>
<kwd-group>
<kwd lng="en"><![CDATA[shear stress]]></kwd>
<kwd lng="en"><![CDATA[acoustic Doppler velocimetry]]></kwd>
<kwd lng="en"><![CDATA[log-law]]></kwd>
<kwd lng="es"><![CDATA[esfuerzo cortante]]></kwd>
<kwd lng="es"><![CDATA[velocimetría acústica de efecto Doppler]]></kwd>
<kwd lng="es"><![CDATA[ley logarítmica]]></kwd>
</kwd-group>
</article-meta>
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