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    The analyses on the surface properties of the annealed-diamond membrane

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    Polycrystalline diamond films were deposited using methane/hydrogen gas mixture on silicon substrates by a microwave plasma chemical vapor deposition (MPCVD) system. From X-ray photoelectron spectroscopy (XPS) analysis, the oxygen & the C signals were observed for the as-deposited diamond film. The oxygen signal was due to physiosorbed water or weakly bound oxygen species. After the 800 8C annealing process, the Si/Si (99.8 eV), Si/O (102.8 eV), Si/Ox (104.8 eV) & the C/O (286.5 eV) bonds appeared for the surface of the diamond film. Moreover, it was shown that the film quality was improved by the 800 8C annealing process. However, it was found that the oxygen signal decreased & the silicon & silicon/oxide bonds almost disappeared for the top surface of the annealed-diamond membrane. It was suggested the oxidized dangling bonds & the silicon components on diamond crystallite surfaces were etched away partly by back-etching process. Furthermore, from Auger electron spectroscopy (AES) analyses, the oxygen & the silicon signals were approximately estimated to be more than 1100 A ° from the bottom surface of annealed-diamond membrane. This indicated that the non-diamond components (included the SiC, SiO2 & amorphous carbon, etc.) in the diamond/silicon interface might be thermally diffused through the grain boundaries to the top surface of the annealeddiamond membrane. These findings may be influential in the development on the characteristic of diamond electrical devices in the future

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The 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

    Electrical properties and physical characteristics of polycrystalline diamond films deposited in a microwave plasma disk reactor

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    Thesis (Ph. D.)--Michigan State University. Department of Electical Engineering, 1992Includes bibliographical references (pages 202-213

    Variations on the Author

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    “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

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    We 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

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    We 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

    Author Index

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