1,720,955 research outputs found
Comparative analysis of methods to extract soiling losses. assessment with experimental measurements
No full textThe impact of soiling on the energy yield of PV systems has recently become a major concern for PV owners, as soiling losses have reduced significantly the revenues of several PV sites. However, a large number of PV plants still lack the equipment to monitor these losses. An appropriate knowledge of soiling losses in PV modules can significantly increase the economic profits, even if possible without any specific soiling monitoring system. In this study, a first comparison of different analytical methods to extract losses due to soiling from PV performance data, without the need for specific soiling sensors, is presented. The study is based on outdoor PV power, irradiance and module temperature measurements. The experimental campaign is conducted in a low-moderate soiling location. The first results show that two of the methods assessed in this work can estimate soiling trends with a relative high accuracy, thus allowing planning adequate cleaning schedules
Short-term impact of the COVID-19 lockdown on the energy and economic performance of photovoltaics in the Spanish electricity sector
Full text linkThe present work investigates how the COVID-19 related lockdown imposed in Spain in between March and June 2020 affected the national electricity sector and the share of photovoltaics in the energy mix. The analysis is conducted by comparing actual electricity demand, generation and price data with forecasts based on their pre-lockdown trends. The results show that the lockdown decreased the electricity demand by 11%, and affected even more severely the price of electricity, causing a total loss for the electricity sector of 6.1 million € per day. These losses were unevenly distributed among the different power technologies of the energy mix. The market share of photovoltaics raised by almost 1% because of the lockdown-related demand drop, even if it performed at capacity factors lower than expected. Overall, because of the lockdown and of the recently installed capacity, photovoltaic provided, for the first time, more than 9% of the national electricity consumed in June 2020, more than twice the maximum share achieved in the previous years
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Full text linkWe 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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