Synchronous frequency support of photovoltaic power plants with inertia emulation

©2019 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.Grid stability is one of the main concerns in renewable energies. The lack of inertia and their low capability to provide frequency support has created the need for implementing new control strategies to solve this problem. In current networks, frequency and voltage support are performed through synchronous generators, which provide an inherent grid support due to the inertia presented in their mechanical rotors. Based on the same concept, renewable energies based on power converters have introduced synchronous controllers to emulate the dynamic behavior of synchronous generators and provide voltage and frequency support. However, most synchronous control strategies integrate their controllers as an add-on firmware embedded in each power converter, without presenting a coordinated synchronous performance when several converters operate in a PV power plant. The aggregation of several power converters operating with a coordinated synchronous response would be advantageous in these cases, since they can provide a harmonic response with an automatic power distribution when grid support is required. This paper presents a synchronous control strategy for photovoltaic power plants, which manages several power converters as an aggregated synchronous system.Peer ReviewedPostprint (author's final draft

Relación entre jarositas de ambientes naturales y sus análogos sintéticos

Depto. de Mineralogía y PetrologíaFac. de Ciencias GeológicasTRUEpu

Demo 25. Movimiento de electrones en campos E y B: el ciclotrón

Objetivo:1.- Observar el proceso de generación de cargas libres. 2.- Observar el movimiento de cargas en campos eléctricos y magnéticos. Estudio experimental del movimiento de electrones en un campo magnético uniforme. Demostración de la Fuerza de Lorentz sobre electrones mediante la observación y medida de la trayectoria circular generada en un campo magnético uniforme, habiendo acelerado previamente los electrones con un campo eléctrico. Medida de la relación carga/masa de los electrones

Relevance of Skills in Total Quality Management in Engineering Studies as a Tool for Performing Their Jobs

[EN] The Spanish higher education system needs to adapt to the requirements of the European Higher Education Area and to this end, it is necessary for higher education institutions to improve the quality of university education, leading to an increase in competency-based learning activities aimed at developing the skills of graduates. Since university graduates face a large number of requirements when entering the labour market, they need to develop and constantly update the appropriate skills to carry out their work properly. This paper aims to address two fundamental questions. First, do engineering graduates need acquired skills in Total Quality Management (TQM) to perform their jobs successfully? Secondly, which job profile requires the highest level of Total Quality Management training and knowledge? We carried out different multivariate statistical analyses using a sample of engineering graduates who had been in the labour market for two years. The results show that knowledge of this type of management philosophy is necessary for adequate job performance. The job profile requiring the highest level of skills in TQM is described.Martínez-Gómez, M.; Jabaloyes Vivas, JM.; Carrión García, A. (2020). Relevance of Skills in Total Quality Management in Engineering Studies as a Tool for Performing Their Jobs. Sustainability. 12(5):1-15. https://doi.org/10.3390/su12052065S115125Kanji, G. K., Malek, A., & Tambi, B. A. (1999). Total quality management in UK higher education institutions. Total Quality Management, 10(1), 129-153. doi:10.1080/0954412998126Heijke, H., Meng, C., & Ramaekers, G. (2003). An investigation into the role of human capital competences and their pay‐off. International Journal of Manpower, 24(7), 750-773. doi:10.1108/01437720310502113Jaca, C., & Psomas, E. (2015). Total quality management practices and performance outcomes in Spanish service companies. Total Quality Management & Business Excellence, 26(9-10), 958-970. doi:10.1080/14783363.2015.1068588Chen, R., Lee, Y.-D., & Wang, C.-H. (2018). Total quality management and sustainable competitive advantage: serial mediation of transformational leadership and executive ability. Total Quality Management & Business Excellence, 31(5-6), 451-468. doi:10.1080/14783363.2018.1476132Weil, S. (1999). Re-creating universities for ‘beyond the stable state’: from ‘Dearingesque’ systematic control to post-Dearing systemic learning and inquiry. Systems Research and Behavioral Science, 16(2), 171-190. doi:10.1002/(sici)1099-1743(199903/04)16:23.0.co;2-aSleezer, C. M., Gularte, M. A., Waldner, L., & Cook, J. (2008). Business and Higher Education Partner to Develop a High-Skilled Workforce: A Case Study. Performance Improvement Quarterly, 17(2), 65-81. doi:10.1111/j.1937-8327.2004.tb00308.xPossa, G. (2006). Europe’s Universities in Response to Europe’s Challenges. Higher Education in Europe, 31(4), 355-357. doi:10.1080/03797720701302907Andrews, J., & Higson, H. (2008). Graduate Employability, ‘Soft Skills’ Versus ‘Hard’ Business Knowledge: A European Study. Higher Education in Europe, 33(4), 411-422. doi:10.1080/03797720802522627Yusof, S. M., & Aspinwall, E. (2000). Total quality management implementation frameworks: Comparison and review. Total Quality Management, 11(3), 281-294. doi:10.1080/0954412006801Dean, J. W., & Bowen, D. E. (1994). MANAGEMENT THEORY AND TOTAL QUALITY: IMPROVING RESEARCH AND PRACTICE THROUGH THEORY DEVELOPMENT. Academy of Management Review, 19(3), 392-418. doi:10.5465/amr.1994.9412271803Hellsten, U., & Klefsjö, B. (2000). TQM as a management system consisting of values, techniques and tools. The TQM Magazine, 12(4), 238-244. doi:10.1108/09544780010325822Curry, A., & Kadasah, N. (2002). Focusing on key elements of TQM – evaluation for sustainability. The TQM Magazine, 14(4), 207-216. doi:10.1108/09544780210429816Hackman, J. R., & Wageman, R. (1995). Total Quality Management: Empirical, Conceptual, and Practical Issues. Administrative Science Quarterly, 40(2), 309. doi:10.2307/2393640Singh, P. J., & Smith, A. J. R. (2004). Relationship between TQM and innovation: an empirical study. Journal of Manufacturing Technology Management, 15(5), 394-401. doi:10.1108/17410380410540381Asif, M., Searcy, C., Garvare, R., & Ahmad, N. (2011). Including sustainability in business excellence models. Total Quality Management & Business Excellence, 22(7), 773-786. doi:10.1080/14783363.2011.585784Rocha-Lona, L., Garza-Reyes, J. A., Lim, M. K., & Kumar, V. (2015). Corporate Sustainability and Business Excellence. 2015 International Conference on Industrial Engineering and Operations Management (IEOM). doi:10.1109/ieom.2015.7093844Zink, K. J. (2007). From total quality management to corporate sustainability based on a stakeholder management. Journal of Management History, 13(4), 394-401. doi:10.1108/17511340710819615Lagrosen, Y., & Lagrosen, S. (2019). Creating a culture for sustainability and quality – a lean-inspired way of working. Total Quality Management & Business Excellence, 1-15. doi:10.1080/14783363.2019.1575199Motwani, J. (2001). Critical factors and performance measures of TQM. The TQM Magazine, 13(4), 292-300. doi:10.1108/13683040010362300Rahman, S. (2001). A comparative study of TQM practice and organisational performance of SMEs with and without ISO 9000 certification. International Journal of Quality & Reliability Management, 18(1), 35-49. doi:10.1108/02656710110364486Petroni, A. (2002). Critical factors of MRP implementation in small and medium‐sized firms. International Journal of Operations & Production Management, 22(3), 329-348. doi:10.1108/01443570210417623Brah, S. A., & Ying Lim, H. (2006). The effects of technology and TQM on the performance of logistics companies. International Journal of Physical Distribution & Logistics Management, 36(3), 192-209. doi:10.1108/09600030610661796Hervás Jorge, A., Ayats, J. C., Desantes, R., & Juliá, J. F. (2012). Las prácticas en empresa como uno de los ejes vertebradores de la empleabilidad. Revista Iberoamericana de Educación Superior. doi:10.22201/iisue.20072872e.2012.8.70Kass, G. V. (1980). An Exploratory Technique for Investigating Large Quantities of Categorical Data. Applied Statistics, 29(2), 119. doi:10.2307/2986296Kaiser, H. F. (1958). The varimax criterion for analytic rotation in factor analysis. Psychometrika, 23(3), 187-200. doi:10.1007/bf0228923

Experiência de cooperação em Turkana (Kenya). Um olhar enfermeira

Hablar de Cooperación internacional en muchas ocasiones nos genera cierta imagen asociada con conceptos muy alejados de lo que realmente es. Lo que vamos a plasmar en esta experiencia no pretende alarmar, ni crear escenarios manipulados, ni magnificar la pobreza, la falta de recursos o la miseria humana… tan solo pretende ser fiel a una realidad tan lejana y cercana al mismo tiempo como la que narramos. Dos enfermeros y un profesor de la Universidad de Alicante (España) desarrollan en Turkana (Kenia) un proyecto de intervención Comunitaria en la que la participación de la población es el eje de su desarrollo. El principal objetivo de la intervención es la identificación de las principales necesidades de salud y la manera como la población puede responder a ellas de manera autónoma y responsable. El proyecto se inicia con la identificación de los líderes comunitarios a través de los cuales se interviene en la comunidad para iniciar el proceso de educación para la salud que dé respuesta a las necesidades de salud de ésta. Tras casi un año de intervención se han logrado objetivos clave relacionados con la higiene, la alimentación y la atención al embarazo y parto.Speaking of international cooperation on many occasions we generate some associated with concepts far removed from what really is image. What we will capture in this experience it is not intended to alarm or create scenarios manipulated or magnify poverty, lack of resources or human misery ... only pretend to be faithful to reality as far and near at the same time as we tell. Two nurses and a professor at the University of Alicante (Spain) developed in Turkana (Kenya) a draft Community intervention in which public participation is central to its development. The main objective of the intervention is to identify major health needs and how people can respond to them independently and responsibly. The project is initiated by identifying community leaders through whom are involved in the community to begin the process of health education which responds to the health needs of the latter. After almost a year of intervention have been achieved key objectives related to hygiene, nutrition and care during pregnancy and childbirth.Falando da cooperação internacional em muitas ocasiões que gerar algum associado com conceitos muito longe do que realmente é a imagem. O que vamos capturar nesta experiencia que não se destina a criar cenários de alarme ou manipuladas ou ampliar a pobreza, a falta de recursos ou a miséria humana ... só que fingir ser fiel à realidade como longe e de perto, ao mesmo tempo que nós dizemos. Duas enfermeiras e um professor da Universidade de Alicante (Espanha) desenvolvido em Turkana (Kenya) um projecto de interven-ção comunitária em que a participação pública é fundamental para o seu desenvolvimento. O principal objetivo da intervenção é identificar as principais necessidades de saúde e como as pessoas podem responder a eles de forma independente e responsável. O projeto é iniciado através da identificação de líderes comunitários através do qual estão envolvidos na comunidade para iniciar o processo de educação em saúde que responde às necessidades de saúde deste último. Depois de quase um ano de intervenção foram alcançados objectivos fundamentais relacionados à higiene, nutrição e cuidados durante a gravidez eo parto

Influence of the ICFF decoupling technique on the stability of the current control loop of a grid-tied VSC

© 2019 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes,creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.The control scheme of grid-tied converters is often implemented in the dq-frame due to simplicity of design. However, with this transformation, there exists an inherent cross-coupling term between the d-and q-channels which is often compensated for by using a feed-forward term in the current-control loop. It is shown, by applying the generalized Nyquist criterion (GNC) to the dq-frame ac impedance of the converter, that the inclusion of this decoupling term, in fact, degrades the stability of the controller when increasing the bandwidth of the synchronous reference frame phase-locked loop (SRF-PLL). Harware-in-the-loop (HIL) experiments are also conducted and verify these results.Peer ReviewedPostprint (author's final draft

Geoguía 3: El Distrito Minero de La Unión, plomo, zinc, plata y estaño en la Sierra de Cartagena

El distrito minero de La Unión (Murcia) es uno de los sitios de interés geológico y minero más importantes de España, y junto con los distritos de Mazarrón y Rodalquilar constituye un extraordinario ejemplo de la relación entre el magmatismo mioceno del SE de España, la tectónica y los procesos metalogénicos. El distrito de La Unión ocupa una superficie de unos 10 x 5 km que encierra la mayor concentración de mineralizaciones de Pb-Zn de las Béticas y una de las mayores de España

Scientific, Educational, and Environmental Considerations Regarding Mine Sites and Geoheritage: A Perspective from SE Spain

Should abandoned mine sites be eligible for some official protection under the umbrella of geoconservation? Providing they have enough educational and scientific value, the answer is affirmative, and we suggest that they should be granted protection at the level of geoheritage sites. Some may see mining as an environmental disaster, but others, with a more geologically oriented mind, may perceive mining as a blessing. Mining unveils the geology, thus allowing a more comprehensive vision of geological features such as rock units, faults, minerals, etc. We analyze the advantages and disadvantages of abandoned mines and districts as geologic observational sites, through the analysis of two mining districts from SE Spain: Mazarrón and Cartagena–La Unión. We propose that if an abandoned mine site or district has enough geological value, not only the mining site but also the whole geologic block hosting the ore deposits should also be protected. In this respect, the Sierra de Cartagena, hosting the Cartagena– La Unión district, is a valuable geological asset where an important chapter of the Alpine and late Alpine geologic history of SE Spain is written

Sorprendente, colorido, suave, raro: recursos líticos y preferencias culturales en la arquitectura, escultura y artefactos portables del monumento tipo tholos de Palacio III (Sevilla, España)

The investigation of the Iberian megalithic phenomenon has only recently begun to benefit from the expansion of the technical and scientific potential of modern archaeology. There are still very few Iberian megaliths for which high resolution scientific research has been carried out, providing detailed data on their design, uses and biographies. This paper presents the results of the multi-disciplinary study of the Palacio III tholos, part of a larger megalithic complex located in Almadén de la Plata (Seville). This study is based on a wide-spectrum methodology that integrates geoarchaeology, techno-morphological and functional analysis of portable material culture and graphic analysis, all combined within a meticulously contextual perspective. The results provide a wealth of data on how, through a series of carefully constructed cultural choices, this monument represents a true place of encounter between the locally available geological resources and other resources that were only accessible through contact with neighbouring communities. Whether in its raw state, finely carved in the form of engraved and painted sculptures or transformed into artefacts of high technical and personal value, the materiality of the stone in the Palacio III tholos acquires multiple cultural dimensions that only a modern scientific approach is able to reconstruct.Solo recientemente la investigación del fenómeno megalítico ibérico ha comenzado a beneficiarse de la ampliación del potencial técnico y científico de la arqueología moderna. Todavía son muy pocos los megalitos ibéricos para los que se han realizado investigaciones científicas de alta resolución, capaces de aportar datos detallados sobre su diseño, usos y biografías. En este trabajo se presentan los resultados del estudio del tholos del complejo megalítico de Palacio III (Almadén de la Plata, Sevilla), abordado mediante una metodología multidisciplinar que integra la geoarqueología, el estudio tecnomorfológico y funcional de la cultura material portable y el análisis gráfico, dentro de una meticulosa valoración contextual. Los resultados aportan datos muy novedosos respecto a cómo, a través de una serie de elecciones culturales cuidadosamente construidas, este monumento representa un verdadero lugar de encuentro entre los recursos geológicos localmente disponibles y los recursos accesibles mediante contacto con otras comunidades. Bien en su forma bruta, bien labrada en forma de esculturas grabadas y pintadas o transformada en artefactos de alto valor técnico y personal, la materialidad de la piedra adquiere en Palacio III múltiples dimensiones culturales que solo a través de la moderna investigación científica es posible reconstruir.This study has been funded by the project of “Nature, Society and Monumentality: High Resolution Archaeological Investigations on the Megalithic Landscape of Antequera” (HAR2013-45149-P) (2014-2017), sponsored within the National R&D Plan of the Ministry of Economy and Competitiveness (Spanish Government)

Factores de riesgo asociados a mortalidad neonatal en el servicio de neonatología del Hospital Humberto Alvarado del Departamento de Masaya en el periodo de Enero 2011 a Diciembre 2013

La Organización Mundial de la Salud (OMS) define la mortalidad neonatal como la muerte producida entre el nacimiento (niño que después de la expulsión completa de la madre, independientemente de la edad gestacional, respire o dé alguna señal de vida) hasta los 28 días de vida, la mortalidad neonatal constituye un indicador básico para expresar el nivel de desarrollo que tiene la atención del recién nacido en una determinada área geográfica o en un Servicio. (mundial, B.2014). Según el Banco Mundial y la OMS en sus últimos reportes revelan que la mortalidad neonatal de Nicaragua en el año 2012-2013 se mantuvo en 12 fallecidos por cada 1000 nacidos vivos, situándose en la región centroamericana en segundo lugar ala para de honduras (honduras= 12*1000; Guatemala: 15*1000; costa rica: 6*1000) sin poder superar aun a nuestra vecino costa rica quien lleva el primer lugar en la reducción de mortalidad neonatal. (OMS,2014) Los factores riesgo asociados a muerte neonatal se han identificado sociodemográficos (la edad materna menor a 15 años y el analfabetismo), los factores de riesgo Obstétricos (periodo Intergenesico mayor de 2 años, multigesta, primigestas, la Hipertensión arterial).En relación al neonato (peso por debajo de 2500 gramos al nacer y la edad gestacional menor a 37semanas, Además la depresión moderada del Apgar y la depresión severa). (mundial, B. 2014) Tres son las causas que explican las tres cuartas partes de la mortalidad neonatal en el mundo: partos prematuros (29%), asfixia (23%) e infecciones graves tales como sepsis y neumonía (25%) (OMS, 2015). Con el presente estudio se pretende conocer cuáles son los factores de riesgo más frecuentemente relacionados con muerte neonatal y poder incidir en la prevención del mismo con el fin de reducir las muertes neonatales en el hospital Humberto Alvarado Vázquez