1,720,968 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
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
Tomographic Imaging of Flow Processes
No full textX-ray computed tomography (CT) is a powerful metrology that allows for nondestructive imaging of the internal structure of objects. Improvements in X-ray sources, X-ray detectors and increasing computation power have paved the way for dynamic tomography, which enables a new range of experiments. Dynamic experiments are ubiquitous in research fields such as carbon storage, geothermal energy, multiphase flow, rock deformation and research related to the oil and gas industry. The dynamic nature of the experiments constrains the imaging process in that the imaging has to be sufficiently fast to capture it. This constraint can drastically compromise the image quality of tomographic reconstructions if either exposure time or the number of projections is reduced to accommodate the pace of the dynamic experiment. In this thesis, we have developed novel reconstruction algorithms for dynamic experiments to provide high-quality reconstructions despite substandard data. We designed the algorithms for experiments that allow for a high-quality scan of the experiment before any dynamics take place. All algorithms we developed are based on the Simultaneous Iterative Reconstruction Technique, and the best performing of these algorithms had two additions, which improved it. The first addition is we initialise a reconstruction for a given time step with a reconstruction of the previous time step. The first time step is initialised with a high-quality reconstruction of the static system. The second addition is that each pixel in the dynamic reconstructions is constrained such they can only take a single value or a range of values. This constraint is derived from a segmentation of the high-quality reconstruction. We tested the algorithms with simulated data of differing quality to gauge their performance under different conditions. We showed that this algorithm performs far better than conventional methods and allows for a substantial reduction in imaging time. We also examined multiple stopping rules for reconstruction algorithms that estimate the optimal point to terminate a reconstruction. Terminating a reconstruction before or after the optimal point will either result in a blurry or noisy reconstruction. All tested methods provided accurate estimates of the optimal stopping point for data with a moderate or small signal to noise ratio (SNR). Two of the methods do not require any knowledge of the noise level in the data, which makes them very practical. Finally, we performed a dynamic CT experiment to study the scaling formation process. We injected a carbon steel flow cell with water supersaturated with BaSO4 for over 150 hours while imaging it with a CT scanner. We used a modified version of one of the reconstructions algorithms we developed to reconstruct the dynamic data to improve the SNR of the reconstructions. Quantitative analysis of the reconstruction allowed us to gain new insights into the scaling formation process. From this analysis, we show that scaling formation has three distinct growth phases. This thesis and the contributions within it shows the applicability of dynamic tomography for a wide range of fields and how it provides novel insight within these fields
Vertex Detector Performance for CLICdet, FCCee & FCChh.
No full textThe performance of the vertex detectors planned for CLICdet, FCCee & FCChh was tested in this project. This was done my studying the figure of merit for a vertex detector which is the transverse impact parameter resolution . This was carried out by simulating single at different energies, polar angles, with a uniform distribution in the azimuthal angle . The events were reconstructed and the distribution was fitted with a Gaussian function where the width of the function resulted in . The effect of material budget and fit function on this was also tested
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
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