1,720,955 research outputs found
A Flexibility Management System for Providing Close-to-real-time Power Services: An Experimental Case Study in PVZEN Microgrid Lab
No full textThis paper presents a novel flexibility management system to handle short-term power deviations generated by intrinsic variability in generation and demand, and behind-the-meter flexibility provision in a close-to-real-time framework
(30-second intervals). The proposed system employs an adaptive autoregression algorithm as a short-term forecast of
energy exchange to the grid and a cost-benefit analysis to adjust the power setpoints of the energy devices by means of
redispatching and unit reassignment modules. Experimental case studies are conducted in the PVZEN microgrid laboratory
to validate the proposed system, testing critical scenarios and diverse flexibility requests. The results confirm the optimal
management of the power deviations and the techno-economic feasibility of flexibility supply with real-world equipment,
reducing the total operation cost from 11% to 85% compared to the baseline scenario. Finally, findings of previous studies based on simulations are verified experimentally, validating the influence of variables such as sample frequency, aging
cost models, and flexibility price
Design a suitable event detection strategy for secondary switched control with no communication for islanded microgrids
No full textActualmente, las microrredes eléctricas han emergido como una eficiente solución para la integración de las energías renovables en las redes tradicionales. Diversos estudios han profundizado en el modelado , control y diseño de las proteccion es tant o para microrredes aisladas como para las conectadas a la red. El éxito de las microrredes depende, en gran medida, del avance de las técnicas para su control. Es manifiesta la relación directa que existe entre la robustez de los sistemas y la complejidad de sus redes de comunicación , por lo tanto, cada vez más grupos y centros de investigación están interesados en profundizar en el estudio de las microrredes aisladas con sistemas de contro l sin comunicaciones. Respondiendo a lo anterior, Rey et al [1] plan teó un control secundario conmutado que garantiza la flexibilidad y confiabilidad de la operación y reduce la dependencia a los sistemas de comunicaciones. Para el correcto funcionamiento del protocolo de control es necesario definir una adecuada estrategi a de detección de eventos que permit a suministrar una señal de disparo que ponga en marcha el control de acuerdo a diversas condiciones de calidad y funcionamiento de la microrred . En este trabajo se pretende diseñar esta estrategia de detección de acuerdo a criterios de rendimiento y complejidad. La estrategia de detección de eventos ha sido construida en cuatro etapas. En primer lugar, se realizó una revisión detallada del control secundari o conmutado planteado por Rey et al [1], definiendo las variables y características del control, la información necesaria para su ejecución y los requerimientos del sistema de detección de eventos. Posteriormente, se llevó a cabo un estudio sobre las estrategias de detección planteadas por diferentes autores, enfocándose principalmente en l os métodos para la detección del aislamiento de la microrred , ya que es un problema con aspectos semejantes al problema propuesto en este trabajo de investigación . Por último, una serie de pruebas experimentales fueron ejecutadas en el laboratorio de electrónica de potencia de la Escuela Politécnica Superior de Vilanova i Geltru, EPSEVG, para evaluar las diferentes estrategias de detección, obtener sus resultados y luego por medio de las variables de rendimiento, evaluar su pertinencia, eficienc ia y comportamiento, generando directrices para plantear mejoras y modificaciones que permitan al final, obtener la estrategia más adecuad
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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