1,721,003 research outputs found
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
Sistema semiconductor a base de nanopartículas de plata/poli(N-vinilcarbazol)/polianilina, para aplicación en fotoánodos de celdas fotovoltaicas
Get PDFEn este trabajo se desarrolló un sistema semiconductor a base de nanopartículas de plata/poli(N-vinilcarbazol)/polianilina para ser aplicado como componente de fotoánodos de celdas solares sensibilizadas por colorantes (DSSC). En primer lugar se sintetizaron las nanopartículas de plata a través del método de poliol. Posteriormente se obtuvieron oligómeros de poli(N-vinilcarbazol) (PVK) vía RAFT. Los sistemas semiconductores fueron obtenidos por dos vías: una mezcla física de nanopartículas de plata con PVK y síntesis de nanopartículas de plata in situ. La caracterización de las nanopartículas de plata se llevó a cabo mediante microscopía electrónica de barrido (SEM), difracción de rayos X (XRD) y espectroscopía de absorción UV-vis. El PVK fue caracterizado mediante cromatografía de permeación en gel (GPC), y espectroscopía de impedancia principalmente. Las nanofibras de PAni se caracterizaron mediante STEM, voltametría cíclica y espectroscopía de impedancia. Los sistemas semiconductores fueron evaluados mediante espectroscopia de impedancia para obtener la resistencia a la transferencia de carga (Rp). El sistema semiconductor 1 presentó un valor de 3742 , el cual es menor al del TiO2 (5077 ), que es el material más utilizado como semiconductor en fotoánodos para DSSC. Aunado a esto, también se encontró que posee la capacidad de absorber luz en las regiones del UV, visible e IR cercano, lo cual es una gran ventaja ante el TiO2
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
Síntesis de polímeros conjugados de tipo donador y aceptor con aplicación a la heterounión en bulto de una celda fotovoltaica
Get PDFSe realizó la síntesis y caracterización de polímeros conjugados tipo donador (PAni) y
aceptor (PEDOT) los cuales contienen partículas inorgánicas, como puntos cuánticos
de teluro de cadmio y nanopartículas de oro. Los cuáles serán empleados en la capa
activa con arreglo de heterounión en bulto (BHJ) en un dispositivo fotovoltaico.
Asimismo se sintetizaron materiales cuya función es transportar los huecos (HTL), como
PAni SGO, PEDOT GO exfoliado y PEDOT:PSS. Los huecos generados en el donador,
serán colectados en el ánodo (ITO) y los electrones transferidos al aceptor serán
colectados en el cátodo (Field metal). Los materiales sintetizados presentaron
absorción de fotones en la región UV, ligeramente en el visible y en el infrarrojo
cercano, lo cual se ve directamente reflejado en el valor de su ancho de banda
prohibida con valores de 2.15-2.6 eV. Además, sus propiedades electroactivas
mostraron la posible transferencia electrónica. El cálculo del parámetro de interacción
permitió crear capas delgadas más uniformes, esto con la finalidad de emplear
solventes más apropiados para los polímeros y poder obtener capas de 100-170 nm. El
gran reto en esta propuesta fue la implementación de estrategias para funcionalizar los
polímeros conjugados con materiales cuya función es absorber fotones. Se llevó a
cabo una evaluación preliminar del dispositivo mediante la caracterización corrientevoltaje,
empleando un simulador solar, donde los arreglos que mostraron mayor
eficiencia fueron: ITO/PGO/PDNPAu/FM y ITO/PGO/PD CdTe/FM, con un 0.002 y un
0.003% de conversión de eficiencia, respectivamente
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