On the study of the performance of Photovoltaic power plants

Performance monitoring of different module technologies and system configurations of photovoltaic (PV) systems in South Africa is rare, resulting in-few reports being published based on field results of PV systems installed and operated in South Africa. The goal of this work was to analyse and report on the performance of PV systems by evaluating the energy output of various PV system configurations and module technologies in the central part of South African (southern hemisphere) climatic conditions. To achieve this, a 400 kWp PV Solar plant has been installed and monitored since January 2015 at the Eskom Research and Innovation Centre (ERIC) in Rosherville, Gauteng (26°5'5" South, 28°5 8'1" East and 1625 m above mean sea level). The ERIC plant consists of multi-crystalline silicon (mc-Si) and copper indium gallium selenide (CIGS) thin-film technologies. The plant comprises of two 25° fixed-tilt north facing arrays, two east-west single axis tracking arrays and two 10° fixed shed orientation (East and West) for both module technologies and one north-south single axis tracking for mc-Si. The evaluation was achieved by studying the operation of the PV plant under different weather conditions and the impact of different configurations and technologies by analysing mainly in terms of specific yields normalized per m2 (kWh/kWp/m2). The first part of the study investigates the impact on the overall performance of different PV technologies as a function of the module mounting configuration. The second part presents the PVSyst yield validation for the Eskom Research and Innovation Centre (ERIC) solar PV plant. Normalised yield production calculations were performed for a fair comparison of various configurations. Although CIGS technology has a higher specific yield throughout the year, the normalised yield production per m2 shows that mc-Si technology out-performs CIGS in both fixed north facing and east-west tracking configurations. This study provides an insight to identify the optimal configuration and will also give an indication of suitability of PV technology for deployment in the central part of South Africa, once all design parameters are considered. This information is also useful in evaluating the operational benefits of the plant based on the net energy output. The monitored data and operating experience of the reported PV system can be applied for future projects. It is common at the beginning of any project for photovoltaic (PV) simulation tools to be utilized for yield prediction in order to estimate performance that can be expected. The purpose for PVSyst yield validation in this study was to validate the accuracy of the original PVSyst simulation that were performed using the satellite derived data, PVGIS satellite database for the ERIC PV plant. The validation is done using the actual ground measured solar resource datasets on site by importing them into PVSyst. A brief analysis of the results suggests that the PVSyst model seems to overestimate the yield output relative to the measured values. This due to out-door conditions and environmental factors impacting the PV site. These factors include power outages, module degradation and were unknown during the development phases when original simulations were performed. However, based on the statistical criteria and assessment, it can be concluded that the original PVSyst simulation results are accurate enough as per the MBE and RMSE percentages, however it is noted as well that the modified PVSyst results are more correlated to the measured results in comparison

Taller “Manejando mis emociones” para la resolución de conflictos escolares de los estudiantes de sexto grado de la I.E. 81624

El estudio de investigación está orientado a mejorar la resolución de conflictos escolares afectan la labor educativa y el progreso del educando. Cuyo objetivo general es, Determinar en qué medida la aplicación de un taller Manejando mis emociones contribuye a mejorar la resolución de conflictos escolares en el sexto grado de educación primaria de la institución educativa 81624- Cruz de las Flores - Huamachuco, 2019 Para el recojo de la información se utilizó el cuestionario de resolución de conflictos que consta de 30 ítems. El diseño es pre experimental, y la muestra es de 31 estudiantes, donde 31 estudiantes conforma el grupo experimental cuya selección fue no probabilística. En el procesamiento de datos estadísticos se empleó la media aritmética, la desviación estándar, el coeficiente de variación, la prueba T-Student. Los resultados obtenidos es tc = -9,903 y p = 0,00 < 0.05, con diferencia al grupo control que significa que el taller Manejando mis emociones contribuye a mejorar la resolución de conflictos escolares en el sexto grado de educación primaria de la institución educativa 81624- Cruz de las Flores - Huamachuco, 201

Relación entre la gestión institucional con el clima organizacional en el Instituto de Educación Superior Pedagógico Público “Gran Pajatén”, distrito Juanjuí – 2019

La presente investigación tuvo como objetivo conocer la relación entre la gestión institucional con el clima organizacional en el Instituto de Educación Superior Pedagógico Público “Gran Pajatén”, distrito Juanjuí – 2019, la investigación fue de tipo no experimental, con un diseño de estudio correlacional. La población estuvo conformada por todo el personal equivalente a 27 trabajadores, el tipo de muestreo fue el no probabilístico por conveniencia de la investigadora conformado por toda la población equivalente a 27 trabajadores entre docentes y administrativos del Instituto de Educación Superior Pedagógico Público “Gran Pajatén” distrito de Juanjuí 2019. El instrumento empleado fue el cuestionario de recolección de datos. Los resultados del estudio destacan el tratamiento estadístico según la correlación de Rho de Spearman que es de 0,257 es positivo BAJO; la misma que no es significativa. El estudio concluyo en aceptar la hipótesis de no existe una relación significativa entre la gestión institucional con el clima organizacional; así como se acepta la hipótesis de que el grado de gestión institucional es positiva baja con el clima organizacional toda vez que las dimensiones Planificación, Organización, Dirección, Control, Autonomía, Motivación y Liderazgo su nivel mayor es bajo, predominando sobre los demás niveles

Digital Preservation Practices and Use of Digital Library by Postgraduate Students in selected Universities in South-West, Nigeria.

Digital libraries are established to meet the demands of students who are ever in need of information that must be current, updated and available at a go, to satisfy their academic needs. However, in spite of the benefits accrued to the use of digital library, postgraduate students, hardly make meaningful use of digital libraries. The study therefore investigates digital preservation practices and use of digital library by postgraduate students in selected universities in South-west, Nigeria. The study adopted a descriptive survey research design. The population of the study comprised 29,017 postgraduate students and 363 library personnel in 12 universities in South-west, Nigeria. Multi-stage sampling technique was adopted to draw a sample size of 385 from the postgraduate population, while simple random technique with a sampling fraction of 50% was used to draw a sample size of 182 from the library personnel population. The predominant purpose of digital library use by postgraduate students in the selected universities is for examination preparation ( = 3.36) and to complete assignment ( = 3.29). There is a low frequency of digital library use by the postgraduate students. Copying of old information into new and higher technology media was the predominant digital preservation practice ( = 3.47). The study identified erratic power supply ( = 3.25), slow internet speed ( = 3.15) and inaccessibility of some websites ( = 3.13), as some predominant challenges to digital library use by the postgraduate students. Digital preservation practices do not independently and significantly influence digital library use by postgraduate students: digital preservation practices (β = -.122, P \u3e.05). There is a weak, positive but not statistically significant relationship between digital preservation practices and digital library use by postgraduate students (r = .067, P \u3e 0.05). Digital preservation practices influences the use of digital library by postgraduate students. Libraries should prioritise investment in digital preservation practices and collaborate with other institutions and stakeholders to share best practices, develop common standards, and promote interoperability of digital resources, as this can help to improve the quality and availability of digital resources and facilitate access to resources across different institutions

Library Cooperation and Use of Digital Library by Postgraduate Students in Selected Universities in South-West, Nigeria.

Digital libraries are established to meet the demands of students who are ever in need of information which are current, updated and available at a go, to satisfy their academic needs. However, in spite of the benefits accrued to the use of digital library, postgraduate students, hardly make meaningful use of digital libraries probably because of lack required information which could be made available if digital libraries collaborate with other digital libraries. The study therefore investigates library cooperation and use of digital library by postgraduate students in selected universities in South-west, Nigeria. The study adopted a descriptive survey research design. The population of the study comprised 29,017 postgraduate students and 363 library personnel in 12 universities in South-west, Nigeria. Multi-stage sampling technique was adopted to draw a sample size of 385 from the postgraduate population, while simple random technique with a sampling fraction of 50% was used to draw a sample size of 182 from the library personnel population. The predominant purpose of digital library use by postgraduate students in the selected universities is for examination preparation ( = 3.36) and to complete assignment ( = 3.29). There is a low frequency of digital library use by the postgraduate students. The prominent area of library cooperation among the digital libraries was Inter-library lending ( = 3.43). The study identified erratic power supply ( = 3.25), slow internet speed ( = 3.15) and inaccessibility of some websites ( = 3.13), as some predominant challenges to digital library use by the postgraduate students. There is a weak, positive but not statistically significant relationship between library cooperation and digital library use by postgraduate students (r = .146, P \u3e 0.05). Library cooperation influences the use of digital library by postgraduate students. Libraries should prioritise investment in collaborating with other institutions and stakeholders to share best practices, develop common standards, and promote interoperability of digital resources, as this can help to improve the quality and availability of digital resources and facilitate access to resources across different institutions

Vitamin D receptor genotype BB is associated with higher serum osteocalcin in first pregnancy

Aim: Serum osteocalcin was shown in a previous study on first trimester pregnant women to correlate with bone density and to distinguish between fast and slow bone losers. The objective of the present study is to examine whether serum osteocalcin is related to vitamin D receptor (VDR) BsmI polymorphism in pregnant women. Study design: We determined osteocalcin serum levels and VDR BsmI genotype in 97 healthy first trimester pregnant women consecutively recruited during six months. Results: BB (21%), Bb (38%) and bb (41%) genotypes showed similar osteocalcin serum levels. However, in primigravidas (n=38) the BB genotype was significantly associated with higher mean osteocalcin level (9.67 ng/mL) than the Bb (8.07ng/mL) and the bb genotype (8.14ng/mL), respectively (P<0.05). The VDR genotype was the only independent parameter to correlate with serum osteocalcin (P<0.05). Conclusion: Only primigravidas show in the first trimester a relation between the bone formation parameter serum osteocalcin and the VDR genotype BB which indicates a higher risk of fractures. For further clinical applications serum osteocalcin and VDR genotype should be tested on a cohort of primigravidas including measurements of bone densit

Nivel de calidad educativa de la Institución Educativa “Simón Bolívar”, Otuzco – 2019

El presente trabajo de investigación titulado “Nivel de calidad educativa de la Institución Educativa “Simón Bolívar”, Otuzco-2019” tuvo como objetivo determinar el nivel de calidad educativa de la Institución Educativa “Simón Bolívar”, Otuzco-2019 aplicando el modelo de autoevaluación del Sistema Nacional de Evaluación, Acreditación y Certificación de la Calidad Educativa – SINEACE. Es una investigación básica, el método utilizado fue el cuantitativo, hipotético-deductivo, estadístico, se usó el diseño No experimental – Transversal. La población es de 1235 personas con una muestra conformada por 234 estudiantes, 42 docentes, 3 directivos y 233 padres de familia. Se evaluaron 5 dimensiones. La técnica para el recojo de datos fue la encuesta y como instrumentos, se aplicaron cuatro cuestionarios propuestos por el SINEACE debidamente validados. Para el procesamiento y análisis de datos se utilizó la estadística descriptiva, los resultados han permitido concluir que el nivel de calidad educativa, aplicando el modelo de autoevaluación del SINEACE de la institución educativa “Simón Bolívar”, Otuzco – 2019, en relación a las dimensiones dirección institucional soporte al desempeño docente, trabajo conjunto con la familia y la comunidad, uso de la información e infraestructura y recursos para el aprendizaje, es de poco avance, con 2.3 de calificación.Tesi

Estudio de seguimiento a las egresadas de la Carrera de Secretariado Ejecutivo en español de la FECYT del año 2011 con fines de evaluación y acreditación de carreras

Obtener información sobre el grado de satisfacción de la formación profesional y desempeño laboral de las secretarias egresadas en el año 2011 para cumplir con los requerimientos de evaluación y acreditación de la carrera.Este trabajo de tesis se realizó con el objetivo de dar un seguimiento adecuado a las egresadas de la Universidad ya que no existe ningún tipo de información para poder localizarlas y saber si están o no trabajando, también servirá como respaldo para las secretarias para que den una acertada información de las graduadas e ir mejorando las fortalezas y las debilidades de nuestras egresadas dando mayor énfasis a los requerimientos de las profesionales e ir implementando las diferentes materias que estén fallando, esta investigación se la realizó directamente con las ex-estudiantes mediante una encuesta vía telefónica y personalmente, dando como resultado en la mayoría de las preguntas mucha satisfacción en los conocimientos adquiridos en las aulas universitarias y las falencias en como es el caso del inglés que no recibieron por lo que sugieren implementar esta materia a la malla curricular, como también ampliar las materias de computación, etiqueta y protocolo y darle mayor interés la materia de tributación. La interpretación de los resultados adquiridos mediante la encuesta se la realizó con cuadros estadísticos y de pastel para ver los porcentajes de cada una de las preguntas y así ver tanto las falencias como satisfacciones en los conocimientos adquiridos. La mayoría de las graduadas manifiestan que no recibían cursos de capacitaciones por motivos de tiempo, por lo que sugieren a los directivos de la universidad implementen capacitaciones constantes para estar al día con las actualizaciones en las diferentes materias de profesionalización y estén a un horario acorde a sus necesidades. Nuestra propuesta está basada en los requerimientos de las graduadas como es la de implementar una base de datos para ir recolectando la información de todas las estudiantes que se gradúan en la universidad y tener la información necesaria de ellas para una mejor información al respecto

Efeito bioeconômico de níveis de concentrado no confinamento de novilhos.

O confinamento e uma atividade que possibilita o abate de animais jovens e bem acabados, proporcionando, em geral, carcaças e carne de melhor qualidade. Considerando-se que, no Brasil, ainda não se pratica a adequada remuneração pela qualidade das carcaças e da carne e o concentrado e um dos itens que mais onera os custos operacionais de um confinamento a determinação de um nível ótimo de concentrado, que proporcione uma carcaça com um acabamento mínimo, e uma maneira do produtor conseguir maior produtividade nesta atividade. Foi desenvolvido, no Centro Nacional de Pesquisa de Gado de Corte (CNPGC) da Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA), um experimento com animais da raça Nelore e outro com animais F1 Pardo Suíço-Nelore, visando a determinar-se o ponto ótimo de adição de concentrado, levando-se em conta o desempenho animal, a qualidade das carcaças e o retorno econômico. No experimento com mestiços, observou-se que a conversão alimentar e ganho de peso diário melhoraram com a adição de concentrado, no qual o maior ganho seria ofertando-se concentrado na proporção de 1,65% do peso vivo dos animais. O melhor retorno econômico, entretanto, seria obtido com a oferta de 1% do peso vivo. No experimento com a raça Nelore, o melhor desempenho seria com adição de concentrado na razão de 1% do peso vivo dos animais, enquanto que o retorno financeiro mostrou-se indiferente ao nível de utilização de concentrado. O custo final de todos os tratamentos foi semelhante, pois, quando houve maior custo diário, o tempo de confinamento foi menor, enquanto que quando o gasto diário foi menor o tempo de confinamento foi maior.bitstream/item/104567/1/Efeito-bioeconomico-de-niveis.pd

Silica@zirconia@poly(malic acid) nanoparticles: promising nanocarriers for theranostic applications

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