bluuebunny/crossref_metadata_2025 huggingface dataset:
Statistical Methods for Recurrent Event Analysis in Cohort Studies of CKD
Authors: Yang Wei , Jepson Christopher , Xie Dawei , Roy Jason A. , Shou Haochang , Hsu Jesse Yenchih , Anderson Amanda Hyre , Landis J. Richard , He Jiang , Feldman Harold I. ,   on behalf of the Chronic Renal Insufficiency Cohort (CRIC) Study Investigators
Published: July 2017

Cardiovascular events, such as hospitalizations because of congestive heart failure, often occur repeatedly in patients with CKD. Many studies focus on analyses of the first occurrence of these events, and discard subsequent information. In this article, we review a number of statistical methods for analyzing ordered recurrent events of the same type, including Poisson regression and three commonly used survival models that are extensions of Cox proportional hazards regression. We illustrate the models by analyzing data from the Chronic Renal Insufficiency Cohort Study to identify risk factors for congestive heart failure hospitalizations in patients with CKD. We show that recurrent event analyses provide additional insights about the data compared with a standard survival analysis of time to the first event.
Evidencias metalúrgicas de fundición de cobre en el sitio formativo tardío de Ramaditas, quebrada de Guatacondo, Provincia de Iquique, Chile
Authors: Graffam Gray , Carevic Álvaro , Rivera Mario
Published: July 2017

En la actualidad los recursos cupríferos de la Puna de Atacama atraen la atención de iniciativas mineras internacionales,donde millones de dólares se invierten en la extracción minera de uno de los recursos más ricos del mundo. Los esfuerzos prehispánicos para extraer estos minerales se han hecho evidentes a través del registro arqueológico regional. Sitios con hornos, escoria y molienda se han registrado desde el Período Formativo Tardío al Inka. Los sitios más tardíos han recibido mayor atención, mientras que se sabe poco de evidencias más antiguas o formativas. En este sentido las evidencias del sitio Ramaditas son significativas en cuanto presentan la primera indicación concreta de una fundición de cobre en la región atacameña durante el Formativo Tardío del norte de Chile (500 AC- 300 DC). Los resultados logrados aquí son los más tempranos de la región y proveen una base sólida para comprender la naturaleza de estos avances antes de la incorporación de la región al Estado Tiwanaku en tiempos más tardíos, como también la naturaleza de uno de los focos metalúrgicos más tempranos del Area Centro Sur Andina.ABSTRACTToday, the copper ores of Atacama attract the continued attention of international mining efforts, where millions of dollars are spent in the anual extraction of ore from one of the world’s richest sources. Pre-Hispanic efforts lo tap these ores are evident in the archacological record of the región. Sites with furnace, slag, and crushed ore are seen throughout the región, spanning from the Late Formative Period thougth the Inka Period. Of these, the later sites have received the most attention to date, although much more waits to be done.The archaeological evidence from Ramaditas is significant in that it is the first firm indication of copper smelting in the Atacama region itself during the Late Formative Period of Northern Chile (500 BC to AD 300). The results provided here are the earliest for the región so far, and they provide a firm foundation for understanding the nature of these efforts prior to the incorporation of the region within the Tiwanaku State of later times, as well as the nature of early melallurgy in the South Central Andes in general.
Areas de actividad doméstica en Pueblo Viejo de Tucute (Puna de Jujuy)
Authors: Albeck María Ester
Published: July 2017

La excavación y el análisis de los materiales arqueológicos del recinto 1 de Pueblo Viejo de Tucute, ubicado en la Puna de Jujuy, ha permitido definir diferentes áreas de actividad en el interior de la vivienda. La dispersión areal, asociación y estado de conservación de los materiales permiten proponer áreas preferenciales para el desarrollo de ciertas actividades domésticas como molienda, elaboración y consumo de comidas, almacenamiento y descanso.ABSTRACTThe excavation of house 1 in Pueblo Viejo de Tucute (Puna de Jujuy) and the further analysis of the archaeological finds show differents activity areas inside the dwelling. Preferential áreas for certain domestic activities like grinding, food elaboration and consumption, storage and resting places are proposed following the areal dispersion, association and conservation of the archaeological finds.
El fenómeno “pucara” visto desde la puna jujeña
Authors: Ruiz Marta , Albeck María Ester
Published: July 2017

En los Andes Centro Sur el uso del término pucara es ambiguo, dado que se lo utiliza para denominar tanto fortalezas, poblados fortificados, asentamientos naturalmente inexpugnables o sitios estratégicos que controlan recursos o vías de circulación. Cronológicamente comprenden al menos dos momentos, preincaico e incaico. Se relaciona el surgimiento de este tipo de asentamientos con el contexto social y político de los inicios del Intermedio Tardío en los Andes Centro Sur. En la Puna de Jujuy es escasa la presencia de pucara al menos si lo referimos a algunas de las áreas aledañas (Quebrada de Humahuaca). Esto probablemente se pueda referir a particulares condiciones sociales o económicas en el Intermedio Tardío para esta parte de los Andes.ABSTRACTThe use of the term pucara is rather ambiguous in the South Central Andes. It is used for naming both fortresses, fortified villages, settlements with a very difficult access, or sites with a strategic location regarding resource controlor circulation. Some of these pucara belong to the Inca Period and other are earlier. The emergence of the pucara settlements is related to the political and social conditions in the begginning of the Late Intermediate Period in the South Central Andes. In the Puna de Jujuy the pucara are scarce, at least when we have in mind some nearby areas as the Quebrada de Humahuaca. This can probably be related to particular conditions in this part of the Andes during theLate Intermediate Period.
Aspectos rituales relacionados con el ganado en Santiago de Río Grande (II Región, Chile)
Authors: Lagos Reinaldo , Mendoza Emilio , Ampuero Nolberto , Hernández Nora
Published: July 2017

Se transcribe una entrevista con Emilio Mendoza, comunero del pueblo Santiago de Río Grande (comuna de San Pedro de Atacama), relativa a aspectos rituales del ganado. Se describe la solidaridad social a nivel de las contribuciones comunitarias como aporte en la formación de rebaños para con los jóvenes que inician su vida marital; se hace referencia a las creencias que norman la iniciación de la vida pastoril y a las ceremonias relacionadas con la prosperidad ganadera. Además, se hace especial mención de las divinidades asociadas con el ganado de los rituales de huaqui y chuya y, de las ceremonias de tikavela y pitira.ABSTRACTWe transcribed the text of an interview with Emilio Mendoza, a resident of the pueblo Santiago de Rio Grande (San Pedro de Atacama) about the ritual relationships with livestock. We described the level of social solidarity by which the pueblo interacts in the formation of herds and animal husbandry practices. We make particular reference to the belief in these ceremonies of pastorial living and prosperous breeding. We also make special mention of divinities associated with the livestock, of the rituals of huaqui, chuya, and of the ceremonies of tikavela and pitira.
Apuntes sobre el tema de la identidad cultural en la Región de Tarapacá
Authors: González Cortez Héctor Segundo
Published: July 2017

Este trabajo, redactado bajo la forma de un ensayo, recoge algunos de los componentes que el autor considera relevantes para abordar y problematizar el tema de la identidad cultural en la región deTarapacá. En primer término, se trata la relación entre identidad, historia y nacionalismo, enfatizando la manera en que la constitución de la nacionalidad chilena en un espacio de ocupación expulsa del imaginario cultural el período peruano y, además, por medio de políticas públicas abiertas o no declaradas, desde el Estado se imponen aquellos elementos culturales que, provenientes de la zona centro sur del país, se consideran representativos del deber ser nacional. En segundo lugar, se abordan algunas identidades de grupos particulares o ciertos componentes que todavía parecen influir en la definición de la identidad regional, además de otros que han aparecido más recientemente producto de los procesos de globalización de la cultura y la economía que afectan también a la región. Por último, a manera de conclusión, se tratan algunos elementos que, pese a su importancia pasada, están siendo o han sido relegados al abandono como constituyentes de identidad.ABSTRACTThis paper, drafted under the form of an essay, gathers some of the elements that the author considers relevant in approaching the research problem of the cultural identity issue in the Tarapacá region. The relationship between identity, history and nationalism is treated firstly, emphasizing the way in which the constitution of the Chilean nationality, from its occupation space, expels the cultural imaginary of the Peruvian period; and further more, cultural elements originated in the south central region of the country are imposed as genuine national representative symbols by means of public and not declared politics. Secondly, some identities of particular groups are considered, or some elements that still seem to influence the definition of regional identity with others that have emerged more recently, as a product of the globalization process of culture and economy that also affects the region. Finally and as a conclusion, some other important elements are referred to, even though they have been relegated to a second place and abandoned as constituent of identity.
Pachamama y desarrollo: paisajes conflictivos en el Desierto de Atacama
Authors: Barros Alonso
Published: July 2017

las comunidades atacameñas, este trabajo analiza las disputas que con frecuencia las oponen con el Estado chileno y los efectos de sus políticas económicas. Esas disputas, principalmente expresadas en términosde posiciones contrapuestas respecto de quién debiera tener control sobrelos recursos locales: agua, tierra, subsuelo, paisajes, revelan las divergencias conceptuales y epistemológicas que subyacen a dichos conflictos. Al describir y desconstruir el discurso desarrollista del Estado respecto del territorio en disputa, por un lado, y analizar los modos atacameños de habitar su territorio y poblar su paisaje, por el otro, se hace cada vez más evidente que la Pachamama y el discurso y prácticas del desarrollo chileno están basados en nociones diferentes respecto de la subjetividad, del espacio/tiempo, de la ecología y de cuáles son las relaciones significativas entre ellas. A modo de conclusión, el artículo muestra como estas diferentes perspectivas y epistemologías son proyectadas a nivel administrativo y legal, tanto localmente como a nivel nacional, así como algunas de las estrategias indígenas para contrarrestadas. ABSTRACTDrawing from experience gathered working with Atacameño communities in the Atacama desert, Chile, this paper analyses the clashes that often oppose them to the Chilean State and the effects of its economic policies. These clashes, mainly expressed in terms of exclusive land claims, reveal the different underlying meanings ?land’ as for both the State and the Atacameños. By describing and deconstructing the development discourse the State deploys about the disputed territory, on one side, and analyzing atacameño modes of dwelling the land and populating the landscape, on the order, it becomes increasingly clear how the andean Pachamama (short for Cosmos, land, earth) and Development discourse are based on differing notions of subjectivity, space/time, ecology and meaningful relationships between them. By way of conclusion, the paper shows how these differing views and epistemologies are played out at the administrative and legal fields, both locally and at a national level.
The Unintended, Pernicious Consequences of "Staying the Course" on the United States' No Child Left Behind Policy
Authors: Amrein-Beardsley Audrey
Published: July 2017

The phrase “no child left behind” has become a familiar expression in American education circles and in popular culture. The sentiment implied by these four words is noble. However, the effects of the top-down implementation of the high-stakes testing provisions of the law have been anything but salutary for public school children, teachers, and administrators. This claim is supported by data describing many of the ways in which well-intentioned but desperate educators, from the statehouse to the schoolhouse, have been driven to game the system in ironic defense of the children, teachers, and administrators least equipped to defend themselves. It is argued herein that, instead of reauthorizing the stronger accountability tenet of NCLB, it might do very well to let it fade away.
Punishment in School: The Role of School Security Measures
Authors: Mowen Thomas J
Published: July 2017

Although investigation of school security measures and their relationships to various outcomes including school crime rates (Gottfredson, 2001), perpetuation of social inequality (Ferguson, 2001; Nolan, 2011; Welch & Payne, 2010), and the impact on childhood experiences has seen significant growth within the last 20 years (Newman, 2004; Kupchik, 2010), few studies have sought to explore the impacts of these measures on suspension rates. Using data from the Educational Longitudinal Study (2002), I explore the relationship between security measures and in-school, out-of-school, and overall suspension rates. Results indicate schools with a security officer experience higher rates of in-school suspensions but have no difference in rates of out-of-school or overall suspensions compared to schools without a security officer. No other measure of security was related to higher suspension rates. As prior literature suggests, schools with greater proportions of black students experienced significantly higher rates of all suspension types. Finally, different types of parental involvement correlated with both higher and lower suspension rates.
Secondary School Science Department Chairs Leading Successful Change
Authors: Gaubatz Julie Ann , Ensminger David C
Published: July 2017

A foundational understanding within education leadership literature is that education leaders are expected to guide reform efforts within school systems (e.g., Darling-Hammond, 2001; Evans, 1996; Fullan, 2001). This expectation mirrors organizational development literature that describes leaders as individuals who constructively institute change within their organizations (e.g., Northouse, 2004; Havelock & Zlotolow, 1995; Yukl & Lepsinger, 2005). Although leadership and change are portrayed as codependent and recursive phenomena within both educational and organizational development literature, no scholarship has linked change models with leadership theories (Herold, Fedor, Caldwell, & Liu, 2008). This article describes a multiple case study that explored the relationship between leadership behaviors and the change process through secondary school department chair stories of change. From the analysis of these stories of successful and unsuccessful change attempts, a clearer picture emerged that illustrates how leaders with little control over decisions implement change. Findings included distinct connections between CREATER change process stages (Havelock & Zlotolow, 1995) and specific leadership behaviors related to the Leadership Grid (Blake & McCanse, 1991; Yukl, Gordon, and Tabers, 2002), as well as change-leadership patterns that differentiate successful and unsuccessful change. Based on these findings, suggestions as to how education leaders should approach change attempts within their schools are discussed.
Paying for School Choice: Availability Differences among Local Education Markets
Authors: Lee Jin
Published: July 2017

On the grounds of the school zone discontinuity by parents’ educational level, housing price, and household income, empowering parents to choose children’s schools with their own hands has the potential to improve overall access to education by weakening geographical advantages, or disadvantages, and opening up invisible boundaries between communities. Though recent school choice proposals seem aligned with issues of access to education, little research has paid attention to potential access to and actual utilization of the federal government-initiated choice program in competitive markets. This paper explores whether or not the markets for the public school choice provision under the No Child Left Behind Act of 2001 are ready to serve students at chronically underperforming schools, by representing the geographic distribution of choice availability in a segregated metropolitan area. This study finds that the public school choice provision under the NCLB builds unequal choice settings between school districts.
Destete artificial en ovinos: respuesta de estrés y bienestar animal. Revisión
Authors: Freitas de Melo Aline , Ungerfeld Rodolfo
Published: July 2017

El vínculo oveja-cordero se establece al parto y cambia a lo largo del periodo de lactación hasta el destete natural. El destete artificial es un manejo frecuentemente utilizado en los diferentes tipos de sistemas de producción ovina, que es realizado más tempranamente que el destete natural. Es uno de los eventos más estresantes en la vida del animal, ya que genera cambios fisiológicos y de comportamiento fuertemente indicadores de estrés, pudiendo afectar negativamente la salud y el bienestar animal tanto de ovejas como de corderos, así como los resultados productivos. La presente revisión sintetiza y analiza información sobre cómo se establece el vínculo madre-cría, el desarrollo del mismo durante el período de lactación y el proceso de destete natural, así como los cambios que se producen cuando el destete se adelanta artificialmente. Además, se describe la respuesta generada por el destete artificial y qué factores la afectan, a nivel fisiológico, de comportamiento y productivo. Por último, se presenta la información existente sobre posibles estrategias que permitan minimizar los efectos negativos del estrés de destete artificial. Se agrega información original sobre cómo la variación cualitativa y cuantitativa de la oferta de pastura en los sistemas extensivos de producción ovino pueden afectar la respuesta de destete de los corderos, y manejos con potencialidad práctica que pueden mitigar la respuesta al destete artificial. Se especifican aspectos en los que existe necesidad de investigación para mejorar la comprensión y desarrollar alternativas sobre cómo modular la respuesta de estrés al destete.
Crecimiento y especialización regional del sector pecuario en México, 1994 a 2013
Authors: Rebollar Rebollar Alfredo , Rebollar Rebollar Samuel , Gómez Tenorio Germán , Hernández Martínez Juvencio , De Jesús González Razo Felipe
Published: July 2017

Las políticas macroeconómicas adoptadas por México, ocasionaron una modificación en la estructura productiva del sector pecuario nacional y local. El objetivo del estudio fue determinar el crecimiento de las actividades pecuarias y la especialización regional en ocho regiones de México (Noroeste NO, Norte NR, Noreste NE, Centro-Occidente CO, Centro-Este CE, Sur SU, Oriente OR y Península de Yucatán PE) y evaluar su dinámica económica de 1994 a 2013. Se utilizaron técnicas de análisis regional, como el cociente de localización y el método diferencial-estructural modificado. Los resultados indicaron que en 1994 y 2013, las regiones NO, NE, SU y OR se especializaron en carne de bovino, y esta última, conjuntamente con CE también en pollo. La región NR se especializó en leche; en tanto que en NO, CO y PE fue en carne de cerdo. Las regiones NE, CO y CE también se especializaron en huevo de ave. De 1994 a 2003, las regiones NR, SU, CE y NO fueron dinámicas, ya que el crecimiento del sector pecuario regional (19.94, 11.59, 7.04 y 6.59 %), fue superior al nacional (4.08 %); el resto de las regiones se rezagaron. De 2003 a 2013, la dinámica regional del sector pecuario cambió. Las regiones CO, OR y PE rezagadas en el periodo anterior, fueron dinámicas en este periodo y, las que fueron dinámicas (NO, NR, CE y SU), se rezagaron. La región NE permaneció rezagada durante los dos periodos. Se concluye que el sector pecuario mostró una dinámica y especialización distinta entre las regiones de México.
Caracterización morfológica y molecular de poblaciones de pasto banderi
Authors: Morales Nieto Carlos Raúl , Avendaño Arrazate Carlos , Melgoza Castillo Alicia , Gil Vega Katia del Carmen , Quero Carrillo Adrián , Jurado Guerra Pedro , Martínez Salvador Martin
Published: July 2017

El pasto banderita [Bouteloua curtipendula (Michx.) Torr.] es una especie nativa de importancia ganadera; sin embargo, prácticas inadecuadas de pastoreo han reducido su diversidad genética. Se exploró y analizó la diversidad morfológica y genética de 51 poblaciones de pasto banderita del estado de Chihuahua. Las plantas se trasplantaron bajo condiciones de temporal. Dos años después se realizó la caracterización morfológica. Para evaluar la variabilidad genética se utilizaron marcadores moleculares AFLP. El análisis de componentes principales (ACP) mostró que los tres primeros componentes (CP), explican el 73.83 % de la variación. El CP1 presentó una correlación significativa (P<0.0001) con rendimiento de materia seca (88 %), densidad de tallos (85 %), diámetro de macollo (83 %), altura de follaje (82 %), altura de planta (79 %) y longitud de hoja (65 %). El análisis de AFLP con cuatro pares de iniciadores detectó 186 bandas; 80.67 % (150 bandas) presentó polimorfismo. El mayor porcentaje de polimorfismo (93.75 %) y bandas polimórficas (48) se obtuvo con la combinación de iniciadores EcoRI-ACT+MseI-CTG. Las poblaciones de banderita presentaron alta variabilidad morfológica y molecular. Se detectaron ecotipos (444, 359 y 557) con potencial forrajero de acuerdo a su variabilidad morfológica y molecular para ser incluidos en programas de restauración de pastizales
Síntesis de calostro y desarrollo de las crías por efecto de la inclusión de aceite de soya en la dieta preparto de ovejas de pelo
Authors: Mejía Vázquez Ángel , Vicente Pérez Ricardo , Osorio Yolanda , Avendaño Reyes Leonel , Correa Calderón Abelardo , D. Álvarez Francisco , Macías Cruz Ulises
Published: July 2017

El objetivo fue evaluar el efecto del nivel de inclusión de aceite de soya (AS) en la dieta pre-parto de ovejas de pelo sobre la producción y composición del calostro, desarrollo de las crías en los primeros 10 días postparto y la productividad de la oveja al parto. Un grupo de ovejas multíparas preñadas Katahdin x Pelibuey se asignaron a tres tratamientos (n=10), los cuales consistieron en dietas isoenergéticas e isoprotéicas que contenían: 0, 3 y 6 % de AS/kg de materia seca. Las dietas se ofrecieron del día 100 de gestación al parto. El peso y volumen del calostro aumentaron linealmente (P<0.05) conforme el nivel de AS en la dieta incrementó. El resto de las variables no presentaron efectos lineales ni cuadráticos (P>0.05) por nivel de AS. Entre ovejas alimentadas con y sin AS, o entre ovejas alimentadas con 3 y 6 % de AS, no se observaron diferencias (P>0.05) en peso vivo y condición corporal de las ovejas, así como en la composición del calostro, peso al nacimiento de las crías ni en peso de camada al parto. Se concluye que la adición de 3 o 6 % de AS en la dieta preparto de ovejas de pelo no afectó la composición del calostro, el desarrollo de las crías ni la productividad de la oveja, pero sí afectó la producción de calostro, siendo éste mayor usando un nivel de 6 % de AS en la dieta.
Factores determinantes del rendimiento en unidades de producción de lechería familiar
Authors: Camacho-Vera Joaquín Huitzilihuitl , Cervantes-Escoto Fernando , Palacios-Rangél María Isabel , Rosales-Noriega Fabián , Vargas-Canales Juan Manuel
Published: July 2017

En México las unidades de producción lechera son altamente heterogéneas en cuanto a las condiciones tecnológicas y agroecológicas en que se desarrollan, lo que influye directamente sobre el rendimiento de la ordeña. Este trabajo evalúa la influencia de variables de tipo económico y tecnológico como la escolaridad del productor, el nivel de tecnificación, el tamaño del hato productivo, la inseminación artificial, la presencia de asesoría técnica y el uso de alimento concentrado, sobre el rendimiento obtenido en unidades familiares de producción de la cuenca de Tecamachalco; Puebla. Para verificar este planteamiento empírico se construyó un modelo lineal múltiple y se llevó a cabo una regresión mediante mínimos cuadrados ordinarios. Los resultados mostraron que, a excepción del nivel de tecnificación, todas las variables contempladas en el modelo tuvieron un efecto positivo y significativo sobre la cantidad de litros producidos por vaca por día. Estos resultados cuestionan en buena medida la política de fomento agropecuario que se ha enfocado a la dotación de equipos y habilitación de infraestructura. Se perciben como necesarias políticas públicas y acciones de auto-organización, dirigidas a la mejora de la alimentación de los hatos, a la generalización de la inseminación artificial y a la garantía de asesoría técnica oportuna y de calidad.
Efecto del peso al nacer, tamaño de camada y posición en la ubre sobre el crecimiento de cerdos durante la lactancia y engorda
Authors: Rendón del Águila Juan Uriel , Martínez-Gamba Roberto Gustavo , Herradora Lozano Marco Antonio , Alonso-Spilsbury María
Published: July 2017

Este estudio se realizó para conocer el crecimiento en lactancia y engorda de lechones nacidos con bajo peso en 32 camadas de alta prolificidad, para lo cual se establecieron tres categorías de peso al nacer PBAJO, PMEDIO y PALTO y tres de tamaño de camada BAJA, MEDIA y ALTA; se identificó el pezón asegurado por el lechón durante el nacimiento y la lactancia, y se determinaron los efectos de dichas categorías en variables de peso y ganancia de peso durante la lactancia y la etapa de crecimiento; así como en la grasa dorsal, la profundidad del lomo y el rendimiento en canal a los 160 días. Las camadas de prolificidad ALTA tuvieron una mayor proporción de lechones de bajo peso (26 %) contra 4 % en camadas de BAJA prolificidad; los lechones de PBAJO demoraron más en succionar los pezones (50.37 min) que los de PMEDIO y PALTO (32.44 y 24.34 min respectivamente) y el 67 % de ellos se posicionaron en mayor proporción en los pezones posteriores de la cerda. Los lechones de PBAJO tuvieron menor ganancia de peso en lactancia, 181 g/día contra 211 y 240 g/día en categorías de PMEDIO y PALTO respectivamente, y menor peso a 160 días de edad (86.6 kg vs 95.7 y 101.1 kg). Se concluye que en camadas de alta prolificidad, los lechones de bajo peso tienen el desempeño productivo más bajo independientemente del tamaño de su camada al nacer y el pezón en el que lactaron.
Rendimiento y valor nutricional de tres variedades de sorgo dulce cultivadas en cuatro ambientes de Durango
Authors: Nava Berumen Cynthia Adriana , Rosales Serna Rigoberto , Jiménez Ocampo Rafael , Carrete Carreón Francisco Óscar , Domínguez Martínez Pablo Alfredo , Murillo Ortiz Manuel
Published: July 2017

El sorgo dulce muestra alto rendimiento de forraje para la alimentación de rumiantes. El objetivo fue evaluar el rendimiento y calidad forrajera de tres variedades de sorgo en Durango. En 2014, se evaluaron las variedades Lico, TOM 3 y Mercedes, en la Colonia Hidalgo (CH), Campo Experimental Valle del Guadiana (CEVAG), La Soledad (LS) y La Goma (LG). El diseño experimental fue completamente aleatorio con arreglo factorial y cinco repeticiones. Se evaluó forraje verde (FV), forraje seco (FS), proteína cruda (PC), digestibilidad verdadera in vitro (DIVMS), fibra detergente neutra (FDN), fibra detergente ácida (FDA), lignina (L), celulosa (Cel), hemicelulosa (HE), valor relativo (VRF) y calidad relativa del forraje (CRF). Se observaron diferencias significativas (P≤0.01 y 0.05) entre ambientes y variedades para FV, FS, L, VRF y CRF y entre ambientes para PC, FDN, FDA, CEL, HE y DIVMS. En CEVAG, se registró el mayor rendimiento de FV (75.9 t ha-1) y FS (12.4 t ha-1). El valor más alto de PC se obtuvo en LG (10 %); mientras que la DIVMS fue alta en LS (78.2 %) y más baja en LG (63.9 %). El contenido de L fue más alto en CH (6.3 %) y LG (6.2 %); mientras que, en LS fue de 3.4 %. Exceptuando LG, en todos los ambientes se obtuvo alta calidad forrajera (CRF= 106.7 a 135.0 %). El sorgo es una opción forrajera en Durango, aunque debe cuidarse la fecha de siembra y cosecha, control de insectos, riego y fertilización para incrementar el rendimiento y calidad nutricional.
Neutron shielding properties of a borated high-density glass
Authors: Saeed Aly , El Shazly , El-Okr Mohamed , El-Azm Ali , Elbashar Yahia , Comsan Mohamed , Kansouh Wagdy , El-Sersy Ahmed
Published: July 2017

The neutron shielding properties of a borated high density glass system was
characterized experimentally. The total removal macroscopic cross-section of
fast neutrons, slow neutrons as well as the linear attenuation coefficient of
total gamma rays, primary in addition to secondary, were measured
experimentally under good geometric condition to characterize the attenuation
properties of (75-x) B2O3-1Li2O-5MgO-5ZnO-14Na2O-xBaO glassy system. Slabs of
different thicknesses from the investigated glass system were exposed to a
collimated beam of neutrons emitted from 252Cf and 241Am-Be neutron sources
in order to measure the attenuation properties of fast and slow neutrons as
well as total gamma rays. Results confirmed that barium borate glass was
suitable for practical use in the field of radiation shielding.
A hybrid analytical-numerical method for efficiency calculations of spherical scintillation NaI(Tl) detectors and arbitrarily located point sources
Authors: Noureldine Salam , Badawi Mohamed , Abbas Mahmoud
Published: July 2017

The present work is essentially concerned to introduce a hybrid
analytical-numerical method to calculate the geometrical, the total, and the
full-energy peak efficiency of the spherical NaI(Tl) detector for using
isotropic radiating g-ray point sources. In addition, it calculates the
average path lengths travelled by the photon inside the detector active
medium, in order to study the characteristics of the source-to-detector
configurations. This method was depended mainly on the calculation of the
solid angle subtended by the radioactive point sources, which were situated
at various locations from the detector surface and the photons path lengths
through the detector active medium. Also, taking into account the attenuation
coefficients of all the absorbers between the source and the detector
material itself. The obtained results were compared against one data set
published to show the method's possibility in the calibration process.
Development of two dosimeters for industrial use with low doses
Authors: El-Kelany Moshira , Gafar Sameh
Published: July 2017

The present study involves a comparison between two dosimetry systems. The
first system depends on victoria blue B (incorporating polyvinyl alcohol) as
a thin-film dosimeter. The second system depends on the same dye as a liquid
dosimeter, which is more sensitive to gamma rays. The prepared film/liquid
has a considerable signal that increases upon irradiation and the intensity
of the signal decrease with increasing radiation dose. The gamma ray absorbed
dose for these dosimeters was found to be up to 25 kGy for the thin film and
700 Gy for the liquid form. Radiation chemical yield, additive substance,
dose response function, radiation sensitivity, also before and
after-irradiation stability under various conditions were discussed and
studied.
Health hazards due to the exposure to radon in schools of the Cappadocia region
Authors: Turhan Seref , Akyurek Serdar , Erdogan Mehmet , Kurnaz Asli , Altikulac Aydan
Published: July 2017

This study presents the results of a survey of radon concentrations in
schools (kindergartens, primary schools, secondary schools, high schools,
colleges, and one faculty) located in the province of Nevsehir which is the
center of the Cappadocia region. Radon measurements covered two consecutive
6-month periods in the ground floor classrooms inside the school buildings
and they were performed using a continuous active radon detector (AlphaGUARD
PQ2000 PRO). Data distribution is well fitted by a log-normal curve. The
arithmetic average value of the radon concentrations measured in summer and
winter was found as 75 ? 12 Bqm-3 and 67 ? 10 Bqm-3, respectively. From the
measured results, the effective doses from radon exposures in summer and
winter were estimated as 0.27 and 0.40 mSv and 0.24 and 0.36 mSv for students
and teachers, respectively. The results showed that radon concentration
measured in schools does not pose significant health hazards for students and
teachers.
PENGARUH KECERDASAN INTELEKTUAL PADA PEMAHAMAN AKUNTANSI DENGAN KECERDASAN EMOSI DAN KECERDASAN SPIRITUAL SEBAGAI VARIABEL PEMODERASI
Authors: Pasek Nyoman Suadnyana
Published: July 2017

ABSTRAKPenelitian ini bertujuan untuk mengetahui pengaruh kecerdasan intelektual pada tingkat pemahaman akuntansi, yang dimoderasi oleh kecerdasan emosional dan kecerdasan spritual. Metode penelitian yang digunakan dalam penelitian ini adalah explanatory research, yang akan menjelaskan hubungan kausal antara variabel independen tersebut terhadap variabel dependen dengan dua variabel pemoderasi. Pengumpulan data dilakukan melalui kuesioner dan data sekunder. Sedangkan analisis data yang digunakan meliputi analisis deskriptif, uji asumsi klasik dan analisis verifikatif dengan menggunakan Moderated Regression Analysis (MRA). Berdasarkan hasil penelitian dapat diketahui bahwa (1) Kecerdasan intelektual berpengaruh positif dan signifikan terhadap pemahaman akuntansi. Artinya dengan kecerdasan intelektual yang baik maka mahasiswa akan lebih mudah memahami tentang pemahaman akuntansi, (2) Kecerdasan emosional dapat meningkatkan pengaruh kecerdasan intelektual pada tingkat pemahaman akuntansi secara positif dan signifikan. (3) Kecerdasan spiritual dapat meningkatkan pengaruh kecerdasan intelektual pada tingkat pemahaman akuntansi secara positif dan signifikan.Kata kunci: Kecerdasan Intelektual, Kecerdasan Emosional, Kecerdasan Spiritual, Pemahaman Akuntansi ABSTRACTThis study aims to reveal the effect of the intellectual at the level of understanding of accounting, moderating by emotional intelligence and spiritual intelligence. The method used in this research is explanatory research, which would explain the causal relationship between the independent variable on the dependent variable that is reinforced by moderating variables through hypothesis testing. Data collected through questionnaires and secondary data. While the data analysis includes descriptive analysis, the classical assumption test and verification analysis using Moderated Regression Analysis (MRA).Based on the results of this research is that (1) the intellectual positive and significant impact on the understanding of accounting. This means that with good intelligence quotient, the student will be easier to understand about the understanding of accounting, (2) Emotional intelligence can enhance intellectual influence on the level of understanding of accounting is positive and significant. (3) Spiritual intelligence Can enhance intellectual influence on the level of understanding of accounting is positive and significant. Therefore, someone who has a high spiritual intelligence will also motivate students to study harder and have higher creativity.                                                                              Keywords: Intellectual Intelligence, Emotional Intelligence, Spiritual Intelligence, Understanding Accounting
Super-capacitor integration into hybrid vehicle power source
Authors: V. Bršlica
Published: July 2017

The plug-in hybrid vehicle based on the concept of battery operated vehicle with strong electrical motor(s) and electrochemical battery is for thermal comfort of crew and for occasional elongated travel range completed by generator, which is designed on average traction power only and during of journey is mainly used in co-generative run for cabin heating. Such vehicle efficiency can be improved by the third power source, specifically used only for acceleration and regenerative braking purposes. That role is optimal for super-capacitor, which has very good charging efficiency and can store the energy from braking to the next acceleration. Both these actions are usually very fast with high power in very short time. Its sizing and voltage control is investigated in this paper.
A new design approach for ground source heat pumps based on hourly load simulations
Authors: L. Lamarche  , G. Dupré  , S. Kajl
Published: July 2017

Most design programs for heat exchangers design for Groundsource heat pumps use a superposition of annual, monthly and hourly pulses. Some design methods use monthly and hourly loads. Hourly load simulations are used mostly for simulation purposes but not for design due to longer simulation time. The authors propose a new design approach based on hourly load data with the aid of an accelerated algorithm. The new approach does not use aggregation of loads and simulate the real thermal response of the individual hourly loads.
Energy price-based control strategy of a small-scale head-dependent hydroelectric power plant
Authors: R. Tiainen  , T. Lindh  , J. Ahola  , M. Niemelä  , V. Särkimäki
Published: July 2017

In deregulated electricity markets, the market price of electricity can be used to control power generation in order to obtain maximum revenue. This makes the building of smaller and smaller hydroelectric power stations economically feasible. High price of energy indicates that power demand is high relative to production capacity. Therefore, price-based optimization will enable the production of electricity when it is most needed. In this article, the feasibility of market price based control strategy for a small-scale hydroelectric power station is evaluated. An actual Finnish small-scale hydroelectric power plant is used as the basis for the modeling.
How the efficiency of induction motor is measured?
Authors: S. Corino  , E. Romero  , L.F. Mantilla
Published: July 2017

The efficiency is of paramount importance nowadays due to increasing electrical energy demand, increasing awareness of environmental problems as greenhouse effects and increasing fossil fuel prices.
This paper tries to show the different results between the standards for efficiency evaluation and the necessity of harmonization worldwide. Then, it is going to be explained the different standards for measurement of efficiency, and the main differences between the standards (IEEE 112, IEC 60034-2 and JEC-37).
To complete this study, it is going to be described the steps in order to estimate efficiency on the jobsite and expressed the different efficiency labels motors.
Electrical charge and discharge characteristics of battery under remote control of water level with PV pumping system
Authors: M．Sato  , Y．Ohmi  , S．Kato
Published: July 2017

This paper presents introduction and load characteristics of stand-alone PV pumping system, which was especially designed for rice planting irrigation of small form units, under remote control of water level. By application of these systems, it is expected to increase agricultural fresh water reuse, and to save labor for water management. The feature of this system is simplicity with having the control function of matching to weather condition. We confirmed remote control of water level by using batteries under cloudy.
Control method for the improvement of the efficiency of a fuell cell
Authors: Radu C. DONCA  , Radu BĂLAN  , Vistrian MĂTIEŞ  , Olimpiu HANCU
Published: July 2017

The major breakthroughs that have recently brought fuel cells to the fore-front include the development of low resistance membranes, highly diffusive electrodes, and reduced use of noble metal catalysts. However, in order to obtain the maximum efficiency out of a fuel cell, some parameters like flow control, temperature, water flow and load must be controlled. This paper is focused on the load control. A three-stage SMPS converter is proposed and analyzed. The fuel cell operation and the types of fuel cells are also described. An experimental setup was made using a toy vehicle powered by a fuel cell in order to experimentally prove the theoretical approaches of load control.
A multivariable model for identification of preferred location of wind plants
Authors: Ali Azadeh  , Seyed Farid Ghaderi  , Mohammad Reza Nasrollahi
Published: July 2017

Unique features of renewable energies such as wind energy has caused increasing demands for such resources. In order to use wind energy as a natural resource, environmental circumstances and geographical location related to wind intensity must be considered. Different factors may affect on the selection of a suitable location for wind plants. These factors must be considered concurrently for optimum location identification of wind plants. This article presents an integrated approach for location of wind plants by Data Envelopment Analysis (DEA). Furthermore, an integrated DEA approach incorporating the most relevant parameters of wind plants is introduced.The prescribed approach is tested for twenty five different cities in Iran. This is the first study that considers an integrated DEA approach for geographical location optimization of wind plants. Implementation of the proposed approach would enable the energy policy makers to select the best possible location for construction of a wind power plant with lowest possible costs.
Optimization of a photovoltaic installation supported with hydrogen. Study of the influence of the tilt angle of the modules
Authors: M. Calderón  , A. Ramiro  , J.F. González
Published: July 2017

The aim of this work is to analyze the influence of the tilt angle of the photovoltaic modules on the efficiency of a autonomous photovoltaic installation isolated from power supply and supported with hydrogen by a Fuel Cell. The photovoltaic modules were oriented to face south in all the cases.
Olive stone: a source of energy generation and a suitable precursor for activated carbon production
Authors: S. Román  , J. F. González  , J. M. Encinar
Published: July 2017

This work is focussed on the study of the reactions involved in the process of steam and CO2 gasification of olive stone char, in order to optimize both the energy content in the gas generated and the development of porosity produced in the char.
Optimal operation of paralleled power transformers
Authors: David Trebolle  , Baudilio Valecillos
Published: July 2017

Parallel operation of power transformers is a common practice. Interest is placed on minimizing the reactive current circulation between transformers due to mismatching of electrical properties. Several control schemes have been applied over the years to ensure efficient operation of paralleled transformers with OLTC. These methods rely either on field measurements of circulating currents or on classic Master/Follower approach and usually assume that the paralleled transformers have matching impedances and OLTC positions. On the present work a generalized approach is implemented calculating the circulating current and minimizing losses directly at the System Operation Office and using the distribution system SCADA to control tap position of the paralleled transformers. This permits the determination of optimal tap matching between transformers and calculation of losses under emergency situations where coupling of transformers with slight impedance mismatch might be considered. In the proposed method a map of circulating current is calculated based on the transformer impedance, X/R ratio and OLTC positions, then the optimal tap positions (minimizing losses) under parallel operation are determined.
The application of active filters supported by Pulse Width Modulated Inverters in the harmonic simulation of the high power electric traction
Authors: P. Kiss  , A. Balogh  , A. Dán  , I. Varjasi
Published: July 2017

The paper shows the present results of a long term research work. The authors are working on the modelling of active filtering of harmonics caused by the railways.
To simulate the harmonic penetration and filtering effects of the power electric traction the combination of frequency and time dependent model should be used. This novel method, called double domain simulation is improving the accuracy of the frequency domain simulation. To calculate the sophisticated model of the electric locomotive and active harmonic filter as a non-linear load a time dependent model must be used. The traction supply system together with the equivalent supply network impedance could be calculated in frequency domain. An iteration algorithm is developed converting the variables in every iteration step between the time and frequency domain.
Integrating power quality analysis and protection relay functions
Authors: A. Lisowiec  , A. Nowakowski  , A. Nowakowski
Published: July 2017

In the paper the implementation of power quality analysis functions in protection relay has been presented. The main focus of the research has been on the development of efficient algorithms for voltage and current signals frequency spectrum determination with harmonic and interharmonic content up to 2 kHz. The technique that enables efficient implementation of frequency spectrum determination in protection relay employed in systems with varying line frequency is resampling in the digital domain. The accuracy analysis of the resampling technique applied in a protection relay, taking into account implementation issues, has been carried out.
Speed multipliers for renewable energy systems-hydro and wind
Authors: C. Jaliu  , D. Diaconescu  , R. Saulescu
Published: July 2017

The paper main objective is to extend the library of planetary multipliers that can be used in wind turbines’ and hydro units’ applications, by taking into account the conditions of obtaining higher efficiencies and higher multipication ratios for a reduced overall dimension. The presented solutions are derived from some representative speed reducer by the flow power inversion. By means of these solutions, a comparative analysis of the structural, kinematical and dynamic specific features of different types of planetary speed multipliers is presented in the paper
Statiscal processing of data coming from a photovoltaic plant for accurate energy planning
Authors: Annalisa Di Piazza  , Maria Carmela Di Piazza  , Gianpaolo Vitale
Published: July 2017

This paper presents a statistical approach to manage sampled data coming from a photovoltaic installation. The proposed statistical methods are the kmeans clustering and the normal density probability distribution. The use of the proposed methods allows to simplify the problem of the PV plant energy assessment respect to the option of obtaining the desired information by managing a large amount of experimental observations. The proposed methods represent useful tools for an appropriate energy planning in distributed generation systems.
Comparison of control techniques for three-phase distributed generation based on VOC and DPC
Authors: Graziella Giglia  , Marcello Pucci  , Calogero Serporta  , Gianpaolo Vitale
Published: July 2017

This paper presents a comparison among control strategies of active rectifiers used for grid connected distributed generation systems from renewable sources. The considered techniques are: Voltage Oriented Control (VOC), Direct Power Control (DPC), two DPC based techniques to minimize the Common Mode (CM) emissions called DPC-EMC1 and DPC-EMC2 set up by the authors and their versions based on virtual flux. All the described techniques have been implemented using Matlab-Simulink® environment and PLECS®. In the results the current injected into the grid, the THD of the injected current vs. generated power and vs. DC link voltage and the CM voltage are shown.