16 research outputs found

    Coatings in Photovoltaic Solar Energy Worldwide Research

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    This paper describes the characteristics of contributions that were made by researchers worldwide in the field of Solar Coating in the period 1957–2019. Scopus is used as a database and the results are processed while using bibliometric and analytical techniques. All of the documents registered in Scopus, a total of 6440 documents, have been analyzed and distributed according to thematic subcategories. Publications are analyzed from the type of publication, field of use, language, subcategory, type of newspaper, and the frequency of the keyword perspectives. English (96.8%) is the language that is most used for publications, followed by Chinese (2.6%), and the rest of the languages have a less than < 1% representation. Publications are studied by authors, affiliations, countries of origin of the authors, and H-index, which it stands out that the authors of China contribute with 3345 researchers, closely followed by the United States with 2634 and Germany with 1156. The Asian continent contributes the most, with 65% of the top 20 affiliations, and Taiwan having the most authors publishing in this subject, closely followed by Switzerland. It can be stated that research in this area is still evolving with a great international scientific contribution in improving the efficiency of solar cells

    A Simplified Method to Avoid Shadows at Parabolic-Trough Solar Collectors Facilities

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    Renewable energy today is no longer just an affordable alternative, but a requirement for mitigating global environmental problems such as climate change. Among renewable energies, the use of solar energy is one of the most widespread. Concentrating Solar Power (CSP) systems, however, is not yet fully widespread despite having demonstrated great efficiency, mainly thanks to parabolic-trough collector (PTC) technology, both on a large scale and on a small scale for heating water in industry. One of the main drawbacks to this energy solution is the large size of the facilities. For this purpose, several models have been developed to avoid shadowing between the PTC lines as much as possible. In this study, the classic shadowing models between the PTC rows are reviewed. One of the major challenges is that they are studied geometrically as a fixed installation, while they are moving facilities, as they have a tracking movement of the sun. In this work, a new model is proposed to avoid shadowing by taking into account the movement of the facilities depending on their latitude. Secondly, the model is tested to an existing facility as a real case study located in southern Spain. The model is applied to the main existing installations in the northern hemisphere, thus showing the usefulness of the model for any PTC installation in the world. The shadow projected by a standard, the PTC (S) has been obtained by means of a polynomial approximation as a function of the latitude (Lat) given by S = 0.001 − Lat2 + 0.0121 − Lat + 10.9 with R2 of 99.8%. Finally, the model has been simplified to obtain in the standard case the shadows in the running time of a PTC facility

    Magnetómetro para medida de campos electromagnéticos débiles en la banda ELF

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    Número de publicación: ES2557702 A1 (27.01.2016) Número de Solicitud: Consulta de Expedientes OEPM (C.E.O.) P201400462 (28.05.2014)La invención comprende un sistema para la medición de campos electromagnéticos débiles, en la banda de frecuencias comprendida entre 1 a 100 Hz, donde se localizan señales derivadas de la resonancia natural que ocurre entre la tierra y la ionosfera, las resonancias de Schumann. El sistema está compuesto por un núcleo de material ferromagnético (1) y un conjunto de bobinas separadas entre sí (2), conectadas mediante cables unifilares (8). Un cable de par trenzado (3) conecta el sensor a un sistema electrónico de medida (4) compuesto por un amplificador diferencial (5) al que se acoplan cada par trenzado, en una bifurcación coaxial con las mallas comunes (20), (21) mediante conectores coaxiales (22), (23) y con salida a un convertidor analógico digital (6). La geometría, estructura y materiales del sistema, le confieren sus propiedades de sensibilidad y ancho de banda.Universidad de Almerí

    Unidad Cifradora/Descifradora de Mensajes con información digital, Sistema y Método de Cifrado/Descifrado para Comunicaciones Digitales en Tiempo Real

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    Número de publicación: ES2272130 A1 (16.04.2007) También publicado como: ES2272130 B1 (16.03.2008) Número de Solicitud: Consulta de Expedientes OEPM (C.E.O.) P200402603 (28.10.2004)La invención consiste en un sistema implementado en un microcontrolador o FPGA que cifra y descifra la información mediante un algoritmo de cifrado simétrico basado en una tabla de claves que es recorrida usando un generador de filtro no lineal, produciendo de esta forma una secuencia cifrante que es operada mediante una operación XOR bit a bit dando lugar de este modo palabras de mensaje cifrado o mensaje en claro, dependiendo de si la entrada es el mensaje en claro o el mensaje cifrado respectivamente y mediante la cual, un mismo mensaje puede ser cifrado de muy diferentes formas, dependiendo del momento en el que se cifra.Universidad de Almerí

    Sistema y método de transmisión de datos entre una unidad móvil y una unidad receptora

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    Número de publicación: ES2253080 A1 (16.05.2006) También publicado como: ES2253080 B1 (16.07.2007) Número de Solicitud: Consulta de Expedientes OEPM (C.E.O.) P200401499 (18.06.2004)La invención se refiere a un método y sistema para transmitir datos entre una unidad móvil (1) y una unidad receptora (2), a través de una red (3) asociada a nodos de repetición (31) que reciben los datos, en forma de paquetes, desde la unidad móvil y los transmiten hasta la unidad receptora (2), que está configurada para descartar paquetes que se reciben de forma repetida, mediante el control de un identificador único asociado a cada paquete. Para mayor seguridad en cuanto a cobertura, se puede completar la posibilidad de transmisión vía los nodos de repetición con una forma alternativa de transmitir los datos, por ejemplo, vía GPRS.Universidad de Almerí

    Advances in Solar Energy towards Efficient and Sustainable Energy

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    Conventional energy resources are not climate sustainable. Currently, engineers and scientists are looking for sustainable energy solutions influenced by climate change. A wide variety of sustainable natural energy resources are available, but they require technical solutions for their implementation. The general trend in energy research is based on renewable resources, amongst which solar energy stands out, being the most mature and widely accepted. In this paper, the current state of the sustainable energy system has been analysed. The main purpose is to provide additional context to assess future scenarios. The study of past contributions allows sustainability planning and increasing the welfare of future society. The aim is to highlight global trends in research on sustainable solar energy from 1995 to 2020 through a bibliometric analysis of 4260 publications. According to their linkages, the analysed articles are distributed in nine clusters: Sustainability assessment, Sustainable energy solutions, Environmental payback time analysis, Sustainability of solar energy in different scenarios, Environmental sustainability, Solar energy applications, Sustainable energy optimisation, Energy transition and Energy and sustainable scenarios. The most repeated keywords are Sustainability, Renewable energy, and Solar energy. Energy research and the exploration of new renewable solar resources are still necessary to meet sustainable energy’s future challenges

    Sistema de telemetría para la transmisión de datos desde ambulancia

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    : Actualmente el traslado de pacientes críticos se lleva a cabo mediante un centro de coordinación entre la atención extrahospitalaria y la atención hospitalaria. Las modernas tecnologías de comunicaciones inalámbricas ofrecen la posibilidad de perfeccionar algunos sistemas en el marco de la medicina crítica (urgencias y emergencias), que bajo estas situaciones son muchas las ocasiones en las que se requiere exploraciones complementarias. El sistema de telemetría desarrollado en este trabajo contempla la comunicación en tiempo real de la bioquímica sanguínea del paciente que en determinadas condiciones y ante una fundada sospecha clínica basada en una anamnesia y exploración física adecuadas requieren de este tipo de pruebas diagnósticas para una mejor valoración del estado del paciente. Esto permite mejorar la asistencia en todo momento y la preparación de todos los recursos necesarios y adecuados para la rápida, correcta y eficaz recepción y atención del paciente en el hospital sin coste adicional, ya que igualmente se requerirían estas pruebas en el hospital. Este sistema permite la detección precoz de afecciones que ponen en riesgo inminente la vida de un paciente. Los resultados de las pruebas constata el interés de este nuevo servicio

    Electronics and Its Worldwide Research

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    The contributions of researchers at a global level in the journal Electronics in the period 2012–2020 are analyzed. The objective of this work is to establish a global vision of the issues published in the Electronic magazine and their importance, advances and developments that have been particularly relevant for subsequent research. The magazine has 15 thematic sections and a general one, with the programming of 385 special issues for 2020–2021. Using the Scopus database and bibliometric techniques, 2310 documents are obtained and distributed in 14 thematic communities. The communities that contribute to the greatest number of works are Power Electronics (20.13%), Embedded Computer Systems (13.59%) and Internet of Things and Machine Learning Systems (8.11%). A study of the publications by authors, affiliations, countries as well as the H index was undertaken. The 7561 authors analyzed are distributed in 87 countries, with China being the country of the majority (2407 authors), followed by South Korea (763 authors). The H-index of most authors (75.89%) ranges from 0 to 9, where the authors with the highest H-Index are from the United States, Denmark, Italy and India. The main publication format is the article (92.16%) and the review (5.84%). The magazine publishes topics in continuous development that will be further investigated and published in the near future in fields as varied as the transport sector, energy systems, the development of new broadband semiconductors, new modulation and control techniques, and more

    Progress in the Knowledge, Application and Influence of Extremely Low Frequency Signals

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    This paper describes the characteristics of contributions made by researchers worldwide in the field of ELF (extremely low frequency) waves from 1957 to 2019. The data were collected through the Scopus database and processed with analytical and bibliometric techniques. The selection of the keywords is an essential step, because ELF has a very different meaning in some areas of medicine, where it is associated with a gene. A total of 12,436 documents were worked on in 12 thematic communities according to their collaborative relationships between authors and documents. Studies included authors publishing in the different thematic areas and the country where the USA stands first with more researchers in this theme than China and Japan. Documents were analyzed from the temporal perspective, their overall contribution, means of publication, and the language of the publication. Research requires extra effort and multidisciplinary collaboration to improve the knowledge, the application, and influence of these field

    Prospective Environmental and Economic Assessment of a Sensor Network

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    Sustainability is becoming of vital importance in project management, and a life cycle assessment (LCA) can ensure a body of knowledge to bear in mind the environmental burdens the project involves. In this study, two different ways of supplying energy to a sensor network are analyzed. Firstly, we analyze the environmental impact of the devices connected to the public grid. Secondly, we analyze the completely full off-grid system, with the sensor connected to a photovoltaic (PV) panel. Our findings show that the off-grid option has a greater number of benefits than the grid-connected option in terms of environmental impacts, although it is less economically advantageous. In a detailed analysis of the off-grid scenario, it can be observed that the battery is the component with the highest impact, so actions to try to reduce consumption, and, therefore, the battery size and its negative impact are taken. After reducing the battery size, the break-even point was reached, providing a net economic benefit of EUR 0.23 sensor/year. However, this analysis refers to a single sensor, and although the environmental and economic benefits seem low, in an economy of scale, this could result in large savings if these types of sensors are massively installed
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