1,720,967 research outputs found
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
Light and elevated temperature induced degradation: defect engineering in boron- and gallium-doped silicon solar cells
No full textLeTID (light and elevated temperature induced degradation) ist ein Phänomen, dasauf einen metastabilen Defekt in Siliziumsolarzellen zurückgeht, der unter Beleuchtung und bei erhöhten Temperaturen auftritt und die Effizienz der Zelle um bis zu 10% verringert. Obwohl die genaue Struktur des Defekts noch unbekannt ist, besteht Konsens darüber, dass Wasserstoff an seiner Entstehung beteiligt ist. Die Hauptquelle von Wasserstoff in Siliziumsolarzellen sind die wasserstoffhaltigen Passivierungsschichten, die bei der Herstellung auf die Siliziumoberfläche aufgebracht werden. Bei hohen Temperaturen steigen die Löslichkeit und Diffusivität von Wasserstoff in Silizium, wodurch dieser aus den dielektrischen Schichten ins Silizium diffundiert und sich dort anlagert.Solche erhöhten Temperaturen (700-830 °C) werden im letzten Herstellungsschritt einer Solarzelle erreicht, um die Metallisierung und das Silizium elektrisch zu verbinden.In dieser Arbeit wurde der Einfluss verschiedener Prozessparameter auf LeTID anLebensdauerproben untersucht. In der Literatur wurde gezeigt, dass durch eine Verringerung der maximalen Temperatur während der Kontaktausbildung LeTID in Bor-dotierten Siliziumwafern verhindert werden kann. In dieser Arbeit wird jedoch gezeigt, dass diese Methode bei Gallium-dotierten Proben deutlich weniger effektiv ist. Eine weitere Methode zur Reduzierung des Wasserstoffgehalts im Silizium besteht in der Änderung der Zusammensetzung der dielektrischen Schichten. Wird eine wasserstoffreiche Schicht direkt auf das Silizium aufgebracht, kann der Wasserstoff leicht in das Silizium diffundieren. Hier wird gezeigt, dass bereits eine 5 nm dicke Zwischenschicht aus Aluminiumoxid als Diffusionsbarriere fungiert und LeTID stark unterdrückt.Eine weitere Methode zur Unterdrückung von LeTID wurde in dieser Arbeit besonders detailliert untersucht und zur Anwendungsreife in der passivated emitter and rear cell (PERC)-Solarzellenproduktion entwickelt. Die Technik beruht auf einer Anpassung des Temperaturverlaufs bei der Kontaktausbildung. Im Standardprozess kühlt eine Solarzelle um etwa 70 K/s ab, nachdem sie ihre Maximaltemperatur erreicht hat. Dadurch sinkt die Diffusivität des Wasserstoffs so schnell, dass dieser nicht auf die ebenfalls verringerte Löslichkeit reagieren kann. Dies führt in der fertigen Solarzelle zu einerWasserstoffkonzentration, die weit über der Löslichkeitsgrenze von Wasserstoff in Silizium bei Raumtemperatur liegt. In dieser Arbeit wird gezeigt, dass bereits eine Verringerung der Abkühlrate auf 50 K/s ausreicht, um LeTID in PERC-Solarzellen aus Bor-dotiertem Cz-, hpm- und SMART-Silizium signifikant zu reduzieren. Im Fall von industriellen Cz-PERC-Siliziumsolarzellen mit mittlerweile typischer Gallium-Dotierung eliminiert die Methode LeTID sogar vollständig. Zudem konnte nachgewiesen werden, dass die entwickelte Methode die initiale Effizienz der Solarzellen nicht signifikant beeinflusst und auch nach dem Temperatureintrag durch den Laminationsprozess eines Moduls weiterhin wirksam bleibt. Im Gegensatz zu bisherigen Methoden zur Vermeidung von LeTID sind keine zusätzlichen Prozessschritte in der Zellherstellung erforderlich.Üblicherweise wird eine Zelle auf LeTID getestet, indem sie für 1100 Stunden erhöhter Temperatur und Beleuchtung ausgesetzt wird. Um die Testzeit zu verkürzen, wird hier eine Methode vorgestellt, die bereits nach 40 Minuten vergleichbare Ergebnisse liefert, indem die Temperatur und die Beleuchtung weiter erhöht werden. Zur Realisierung dieser Bedingungen wurde im Rahmen dieser Arbeit ein Degradationsteststand entwickelt.LeTID (light and elevated temperature induced degradation) is a phenomenon based on a metastable defect in silicon solar cells that occurs under illumination and at elevated temperatures, reducing the cell's efficiency by up to 10%. Although the exact structure of the defect remains unknown, there is consensus that hydrogen is involved in its formation. The main source of hydrogen in silicon solar cells are hydrogen-containing dielectric passivation layers that are deposited on the silicon surface during the manufacturing process. At elevated temperatures, the solubility and diffusivity of hydrogen in silicon increase, allowing it to diffuse from the dielectric layers into the silicon and accumulate there. Such elevated temperatures (700°C to 830°C) are reached in the final manufacturing step of a solar cell to electrically connect the metallization and the silicon.In this work, the influence of different process parameters on LeTID was investigated using lifetime samples. In the literature, it has been shown that by reducing the maximum temperature during contact formation, LeTID can be prevented in boron-doped silicon wafers. However, it is demonstrated in this work that this method is significantly less effective for gallium-doped samples. Another method for reducing the hydrogen content in silicon involves changing the composition of the dielectric layers. If a hydrogen-rich silicon nitride layer is applied directly to the silicon, hydrogen can easily diffuse into the silicon. It is shown here that even a 5 nm thick intermediate layer of aluminum oxide acts as a diffusion barrier and strongly suppresses LeTID.Another method for suppressing LeTID was investigated more intensively in this work and developed to application maturity in passivated emitter and rear cell (PERC) solar cell production. The technique is based on adjusting the temperature profile during contact formation. In the standard process, the solar cell cools down at a rate of about 70 K/s after reaching its maximum temperature. As a result, the diffusivity of hydrogen decreases so quickly that it cannot respond to the also decreased solubility. This leads to a hydrogen concentration in the finished solar cell that is far above the solubility limit of hydrogen in silicon at room temperature. This work demonstrates that merely reducing the cooling rate to 50 K/s is sufficient to significantly reduce LeTID in PERC solar cells made from boron-doped Cz, hpm, and SMART silicon. In the case of industrial Cz-PERC silicon solar cells with a now typical gallium-doping, the method completely eliminates LeTID. Furthermore, it has been shown that the developed method does not significantly affect the initial efficiency of the solar cells and remains effective even after the temperature input from a module lamination process. Unlike previous methods for avoiding LeTID, no additional process steps are required in cell manufacturing.Typically, a cell is tested for LeTID by exposing it to elevated temperature and illumination for 1100 hours. To shorten the test duration, a method is presented here that delivers comparable results after just 40 minutes by further increasing both temperature and illumination. To realize these conditions, a degradation test stand was developed as part of this work
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
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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