1,720,960 research outputs found
Perelman's entropy functional at type I singularities of the Ricci flow
Get PDFWe study blow-ups around fixed points at Type I singularities of the Ricci flow on closed manifolds using Perelman's W-functional. First, we give an alternative proof of the result obtained by Naber (2010) and Enders-Müller-Topping (2011) that blow-up limits are non-flat gradient shrinking Ricci solitons. Our second and main result relates a limit W-density at a Type I singular point to the entropy of the limit gradient shrinking soliton obtained by blowing-up at this point. In particular, we show that no entropy is lost at infinity during the blow-up process.We study blow--ups around fixed points at Type I singularities of the Ricci flow on closed manifolds using Perelman's W-functional. First, we give an alternative proof of the result obtained by Naber and Enders-Mueller-Topping that blow-up limits are non-flat gradient shrinking Ricci solitons. Our second and main result relates a limit W-density at a Type I singular point to the "entropy" of the limit gradient shrinking soliton obtained by blowing-up at this point. In particular, we show that no entropy is lost at infinity during the blow-up process
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
Wie die Zeit vergeht: Rossinis Elisabetta regina d’Inghilterra in Wien
No full textElisabetta is the first opera that Rossini composed for Naples in 1815, the new opera that was performed there after the return of the Bourbons to the throne following the period of French rule, and which was intended to inaugurate the new political course that the reinstalled rulers now wanted to initiate. Elisabetta was very successful in Naples and immediately began to circulate. She came to Vienna for the first time in 1818. However, its success in the Austrian capital did not materialise until 1822, when it was performed as the penultimate opera of the successful Rossini season organised by Barbaja in a version revised by the composer himself. Despite the attention that musicologists have devoted to Rossini's operas in Vienna, Elisabetta has been one of the least researched operas to date. The first part of my paper therefore focuses on the Viennese performances of Elisabetta, particularly those of 1822. On the basis of an analysis of the sources, I discuss the significance of the changes made by Rossini in the context of the changed political conditions since 1815. In the second part, I turn first to the reception of Elisabetta in Vienna; from here I finally discuss the music historiography of the 20th century, and the ideological difficulties that traditionally characterise the historiography of Rossini's success in Vienna in 1822
La voce di Giovanni David
No full textParlare della voce di un cantante dell’Ottocento è come commentare l’arte di un pittore di cui non ci sia pervenuto neppure un quadro: possiamo soltanto affidarci alle testimonianze dei contemporanei. La cosa è ovviamente vera anche per Giovanni David (1790-1864), ma con un vantaggio in più: la sua voce era tanto particolare, insolita, straordinaria (così ci confermano i giornali dell’epoca) che i compositori hanno scritto per lui linee vocali particolari, insolite e straordinarie, offrendoci così in quegli spartiti gli unici dati realmente oggettivi sulla sua voce. L’oggettività di tali informazioni non può tuttavia che limitarsi alla sola estensione, testimoniataci da quelle parti vocali come eccezionalmente acuta; e questo vale anche per le opere di Rossini che David eseguì a Vienna nel 1822. Ma in quale modo egli affrontava quegli acuti? Con quale tipo di meccanismo vocale, in un’epoca in cui sappiamo che altri tenori stavano cercando nuove modalità di emissione, tra falsetto e voce piena? E, soprattutto, possono le descrizioni del canto di David aiutarci a dirimere le incertezze su cosa fosse davvero il falsetto per un tenore di epoca rossiniana
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