1,720,994 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
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
Monitoring occupational trauma of the upper extremities by functional evaluation of the handgrip
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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
High Resolution Scanning Ion Microscopy
No full textThe structure of the thesis is the following. The first chapter is an introduction to scanning microscopy, where the path that led to the Focused Ion Beam (FIB) is described and the main differences between electrons and ion beams are highlighted. Chapter 2 is what is normally referred to (which I do not really like) as ‘the theory chapter’. The theory of ion/matter interaction is presented in the first part of the chapter. The treatment is the standard one that can be found in the literature, but of course mine is the choice of the topics and the way in which they are presented. The second part of the chapter is a short introduction toMonte Carlo codes, and in particular to the two pieces of software that I have used for my basic simulations, SRIM/TRIM from J. Ziegler, and IONiSE from D. Joy. The third chapter is almost entirely made up of an article published in Microscopy & Microanalysis in 2011, on the subject of ion-induced Secondary Electron Emission; the paper is introduced by two small sections, the first being an introduction to ion beam imaging, the second presenting a standard theory of noise in scanning microscopy. Chapter 4 introduces the main topic of this thesis work, the one that is more dear to me: resolution in scanning ion microscopy. The chapter is a hybrid, for the theory of resolution that is presented is quite standard, but interlaced with a lot of rethinking and personal points of view, and finally adapted to the specific field of scanning ion microscopy. Chapters 5 and 6 are the first two articles published during my PhD, in Journal of Vacuum Science & Technology B. They both tackle the problem of resolution evaluation in scanning ion microscopy, the first for the Ga-FIB, the second for the He-FIB. The two papers have been published in 2008 and 2009, respectively, a time when the uniformity of the formalism was not yet mature, reason for which symbolic inconsistencies can be found in relation to the rest of the thesis, and to the list of symbols in appendix B. Choice was made to leave the papers in their published version, but this should not represent a problem, because each quantity is clearly defined. The last journal paper published within my project makes chapter 7. The scope of the paper is broad, for it proposes a method to simulate ion imaging that does not employ any Monte Carlo calculation. It can be regarded as a kind of summary of all the studies performed in the course of the project, and is followed by an appendix that explains the details of the noise analysis whose results are presented in the article. Conclusions and recommendations find their place in chapter 8. With referiment to the original main motivation, i.e. exploring the possibility of achieving atomic resolution with a Scanning IonMicroscope, it is shown that this is not possible, at least in the general case, because the sputtering of the sample limits the ultimate obtainable resolution to the nanometer range, even using very light ions. Also, it is pointed out that, in imaging systems causing strong sample modification, the concept of resolution itself can not be thought of as static; it must be regarded as dynamic instead. On the subject of Ion-Induced Secondary Electron Emission, a procedure to obtain curves of Secondary Electron yield versus incident angle of the beam is presented; the behaviour of those curves contributes to explain the much sharper contrast achievable with a He-FIB, as opposite to the more traditional Ga-FIB. Finally, it is shown that simulation of ion imaging based on the ‘yield vs. incidence angle’ curves is feasible, overcoming the computational problems that affect any Monte Carlo based approach.IST/Imaging Science and TechnologyApplied Science
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
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