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Heat of wood pyrolysis
No full textThe heat of pyrolysis of beech and spruce wood was investigated by means of a differential scanning calorimeter. Wide variations were found for the heat of the primary pyrolysis process, depending on the initial sample weight and on the conditions used in the measurements. However, reporting the heat of the primary pyrolysis process versus the final char yield resulted in a linear correlation. This strong dependency of the heat of wood pyrolysis on the final char yield, that is in turn highly sensitive to the experimental conditions, can explain the uncertainty of the data for the heat of wood pyrolysis reported in the literature. A possible explanation for the variability of the heat of wood pyrolysis depending on the final char yield seems to be an exothermic primary char formation process competing with an endothermic volatile formation process. © 2002 Elsevier Science Ltd. All rights reserved
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
Influence of the emissivity of the sample on differential scanning calorimetry measurements
No full textA possible cause of the wide differences present in the literature values for the calorimetric measurements of the pyrolysis heat of biomass was analyzed. The apparent specific heat of char from pyrolysis of beech wood was investigated by means of a differential scanning calorimeter (DSC). The objective was to find out the influence of the use of a lid on the crucible on the experimental results. In a first experimental series, the crucible containing the sample and the empty reference crucible were closed by a pierced lid. In a second experimental series, the crucible containing the sample and the reference crucible were used without a lid. Results of experiments within the same series showed excellent agreement, but the results of the first series were completely different with respect to those of the second series. A possible explanation for these differences are the different emissivities of the crucible material (aluminium) and char. During experiments without a lid a different radiative heat exchange occurs between the two crucibles and the opposite wall of the DSC measurement cell. In order to confirm the effect of heat radiation inside the DSC measuring cell, additional experiments with aluminium oxide and graphite were carried out. © 2001 Elsevier Science B.V
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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