Control mediante Arduino del movimiento de una antena directiva con un servomotor

El control y mantenimiento de elementos eléctricos que requieren de un contacto directo, pueden poner en riesgo la vida de las personas dedicadas a ello. Por este motivo, se ha hecho necesario diseñar sistemas que permitan revisar el estado de los equipos y que puedan ser controlados a distancia por el usuario. En este caso, la aplicación se basa en controlar de forma remota la posición de una antena cuya finalidad es localizar fuentes de descargas parciales en los aislantes, y diseñar el sistema de adquisición de datos que recoge la información del fenómeno físico. Para generar el movimiento automático se empleará una placa Arduino que controlará la posición del servomotor, encargado de situar el sistema en la dirección indicada, y para captar las señales emitidas por las descargas parciales se empleará una antena directiva que enviará los datos a una tarjeta de adquisición. Este trabajo constituye la base del proyecto “Localización de eventos en radiofrecuencia mediante una antena de alta directividad”, complementario a este. En él, se analizarán las señales proporcionadas por el sistema de adquisición en cada una de las posiciones recorridas por el sistema, y se realizarán varios estudios que determinarán la localización de la fuente de descargas parciales.The control and maintenance of electrical elements that require direct contact can affect the safety of the staff engaged in it. For this reason, the design of systems that allow to check the conditions of the equipment and that can be controlled remotely by the user has become necessary. In this project, the application is based on the remote control of the position of an antenna whose purpose is to locate sources of partial discharges inside electrical insulators, and to design a data acquisition system that acquire information from the physical phenomenon. In order to generate the automatic movement, an Arduino board will be used to control the position of a servomotor, which is the responsible for locating the system in the right direction; and in order to capture the signals emitted by the partial discharges, a directional antenna will send data to an acquisition card. This work is the basis of the project “Location of events in radiofrequency using a high directivity antenna”, complementary to this. In it, the signals provided by the acquisition system will be analyzed in each of the positions covered by the system, and several studies will be tested to determine the location of the source of the partial discharges.Ingeniería en Tecnologías Industriale

Fundamentals and application of voltammetric electronic tongues in quantitative analysis

Altres ajuts: acords transformatius de la UABElectronic tongues (ETs) are bioinspired analytical tools based on the synergies between (bio)sensors and chemometrics. Through the application of chemometrics, it is possible to infer underlying relationships between the measured analytical signals and the chemical properties of the samples, both for descriptive and predictive purposes, otherwise impossible to decipher. Research in voltammetric ETs during the last two decades has demonstrated the benefits derived from the use of sensor arrays with complementary response, together with advanced data treatment methods to enhance their overall performance. In this direction, the different approaches followed when developing voltammetric ETs and some relevant applications in quantitative analysis are reviewed herein

Automatic Irrigation Scheduling on a Hedgerow Olive Orchard Using an Algorithm of Water Balance Readjusted with Soil Moisture Sensors

Recent technological advances have made possible automated irrigation scheduling using decision-support tools. These tools help farmers to make better decisions in the management of their irrigation system, thus increasing yields while preserving water resources. The aim of this study is to evaluate in a commercial plot an automated irrigation system combined with remote-sensing techniques and soil mapping that allows the establishment of regulated deficit irrigation (RDI) strategies. The study was carried out over 3 years (2015–2017) in a commercial hedgerow olive orchard of the variety ‘Arbequina’ located in Alvarado (Extremadura, Spain). An apparent electrical conductivity (ECa) map and a normalized difference vegetation index (NDVI) map were generated to characterize the spatial variability of the plot and classify the zones in homogeneous areas. Then, reference points were selected to monitor the different irrigation sectors. In 2015, the plot was irrigated according to the farmer’s technical criteria throughout the plot. In 2016 and 2017, two different areas of the plot were irrigated applying an RDI strategy, one under expert supervision and the other automatically. The results show that in a heterogeneous plot the use of new technologies can be useful to establish the ideal location for an automatic irrigation system. Furthermore, automatic irrigation scheduling made it possible to establish an RDI strategy recommended by an expert, resulting in the homogenization of production throughout the plot without the need for human intervention.info:eu-repo/semantics/publishedVersio

Epitaxial integration of CoFe₂O₄ thin films on Si (001) surfaces using TiN buffer layers

Epitaxial cobalt ferrite thin films with strong in-plane magnetic anisotropy have been grown on Si (001) substrates using a TiN buffer layer. The epitaxial films have been grown by ion beam sputtering using either metallic, CoFe₂, or ceramic, CoFe₂2O₄, targets. X-ray diffraction (XRD) and Rutherford spectrometry (RBS) in random and channeling configuration have been used to determine the epitaxial relationship CoFe₂O₄ [100]/TiN [100]/Si [100]. Mossbauer spectroscopy, in combination with XRD and RBS, has been used to determine the composition and structure of the cobalt ferrite thin films. The TiN buffer layer induces a compressive strain in the cobalt ferrite thin films giving rise to an in-plane magnetic anisotropy. The degree of in- plane anisotropy depends on the lattice mismatch between CoFe₂O₂ and TiN, which is larger for CoFe₂O₄ thin films grown on the reactive sputtering process with ceramic targets

Multicore fiber scenarios supporting power over fiber in radio over fiber systems

We propose the integration of power over fiber in the next generation 5G radio access network front-haul solutions based on spatial division multiplexing with multicore fibers. The different architectures in both shared- and dedicated- core scenarios for power over fiber delivery and data signals are described. The maximum power to be delivered depending on the efficiencies of the different components is addressed as well as the limits of the delivered energy to avoid fiber fuse and non-linear effects. It is shown how those limits depend on high power laser linewidth, fiber attenuation, link length and fiber core effective area. The impairments related to non-linear effects, multicore fiber crosstalk and temperature are also theoretically analyzed. Experiments show there is no degradation of signal quality for feeding powers of several hundreds of milliwatts for both scenarios in 4-core multicore fibers. This study helps in designing future power by light delivery solutions in Radio over Fiber systems with multicore fibers.This work was supported in part by the Spanish Ministry of Science, Innovation and Universities, Directorate for Research and Innovation at Madrid region, and H2020 European Union programme under Grant RTI2018-094669-B-C32 and Grant Y2018/EMT-4892, and in part by FSE and 5G PPP Bluespace project Grant 762055

INCIDENCIA DE LA EDUCACIÓN FÍSICA EN EL DESARROLLO DE LA EDUCACIÓN MEDIOAMBIENTAL

El presente artículo tiene como objetivo exponer algunas consideraciones teórico-metodológicas en torno al tratamiento de la educación medioambiental en la clase de Educación Física. El análisis de las mencionadas concepciones derivó en el aporte del trabajo, que lo constituyó un conjunto de tareas para desarrollar esta dimensión en el proceso de formación de los futuros profesionales de la salud en la Universidad de Ciencias Médicas de Holguín. Los autores utilizaron métodos de investigación tales como: el análisis-síntesis, la inducción- deducción y el método histórico–lógico, los cuales permitieron elaborar la propuesta que se presenta, así como arribar a generalizaciones teóricas y prácticas. El conjunto de tareas medioambientales se convirtió en una herramienta para elevar la preparación metodológica de los docentes y permitió darle cumplimiento a una de las estrategias curriculares de la formación del profesional referida a la Salud Pública y Formación Ambiental

Fiber-Optic Pyrometer with Optically Powered Switch for Temperature Mesurements

We report the experimental results on a new infrared fiber-optic pyrometer for very localized and high-speed temperature measurements ranging from 170 to 530 degrees C using low-noise photodetectors and high-gain transimpedance amplifiers with a single gain mode in the whole temperature range. We also report a shutter based on an optical fiber switch which is optically powered to provide a reference signal in an optical fiber pyrometer measuring from 200 to 550 degrees C. The tests show the potential of remotely powering via optical means a 300 mW power-hungry optical switch at a distance of 100 m, avoiding any electromagnetic interference close to the measuring point.This work was supported by the Spanish Ministry of Economy and Competitiveness and FEDER program under grants TEC2015-63826-C3-2-R and by Comunidad de Madrid under grant S2013/MIT-2790

Structure and magnetism of ultrathin nickel-iron oxides grown on Ru(0001) by high-temperature oxygen-assisted molecular beam epitaxy

We demonstrate the preparation of ultrathin Fe-rich nickel ferrite (NFO) islands on a metal substrate. Their nucleation and growth are followed in situ by low-energy electron microscopy (LEEM). A comprehensive characterization is performed combining LEEM for structural characterization and PEEM (PhotoEmission Electron Microscopy) with synchrotron radiation for chemical and magnetic analysis via X-ray Absorption Spectroscopy and X-ray Magnetic Circular Dichroism (XAS-PEEM and XMCD-PEEM, respectively). The growth by oxygen-assisted molecular beam epitaxy takes place in two stages. First, islands with the rocksalt structure nucleate and grow until they completely cover the substrate surface. Later three-dimensional islands of spinel phase grow on top of the wetting layer. Only the spinel islands show ferromagnetic contrast, with the same domains being observed in the Fe and Ni XMCD images. The estimated magnetic moments of Fe and Ni close to the islands surface indicate a possible role of the bi-phase reconstruction. A significant out-of-plane magnetization component was detected by means of XMCD-PEEM vector maps

Reporte de desove de Plexaura homomalla (Esper, 1794) en el Parque Nacional Guanahacabibes, occidente de Cuba

El efecto directo del cambio climático y otros factores han colocado a los arrecifes de coral como uno de los ecosistemas más amenazados a nivel mundial. Los octocorales constituyen uno de los grupos macrobentónicos más diversos en los arrecifes y, aunque no intervienen directamente en la construcción de arrecifes, pueden contribuir significativamente al aporte de sedimentos y carbonato de calcio. Además, este es uno de los grupos ampliamente utilizados como indicadores ecológicos de la eutrofización, permitiendo rastrear los aportes antropogénicos de nutrientes en los ecosistemas marino-costeros. El crecimiento y desarrollo a través de la reproducción asexual en los octocorales ("astogenia") se caracteriza por la replicación iterativa de las ramas y los pólipos. Sus patrones generales de reproducción sexual están bien documentados y se encuentran entre los pocos taxa, cuya tasa de fertilización puede ser predecible y medida directamente durante eventos naturales de desoves. En Cuba, el conocimiento sobre el período exacto del desove de gorgonias como Plexaura homomalla es escaso y no existe ningún reporte científico sobre el tema. En agosto de 2019, fue observado el desove de 10 colonias de P. homomalla en el Parque Nacional Guanahacabibes (PNG). Algunos autores plantean que el desarrollo inicial de los gametos ocurre solo cuando la media diaria de la temperatura del mar, durante el mes previo al desove, sobrepasa las 27°C. Este comportamiento se corresponde con los valores de temperatura durante los meses de junio y julio en el Parque Nacional Guanahacabibes, previos al desove de P. homomalla; lo que pudiera explicar la observación del desove en el mes de agosto. No obstante, no se puede asegurar que el desove ocurrió solamente en el mes de agosto, pues no se cuentan con datos de los meses de junio y julio, pico reproductivo descrito para la especie.Esta investigación ha sido parcialmente financiada por el proyecto "Cultivo y propagación de corales pétreos para la restauración de arrecifes en Cuba" y por la ONG The Nature Conservancy. Nos gustaría agradecer especialmente a: Lic. Mileidy Soto Vazquez, Téc. Miraysis Noda Redonet, MSc. Juliett González Mendez, Dr. Ramón Alexis Fernández Osoria, Raidel Hayes Mirabal, Víctor Isla Lara, Adrián Sánchez, Abel Castro, Romel Castillo Serrano, María de los Ángeles Serrano Jerez, Reynaldo Estrada y al personal del Centro Internacional de Buceo "María la Gorda" por su colaboración y participación durante la expedición; a la ONG The Nature Conservancy por el apoyo logístico