1,720,966 research outputs found
Estimating Soil Thermal Conductivity by Weighted Average Models with Soil Solids as a Continuous Medium
Get PDFIn an attempt to further simplify and to refine the modeling of soil thermal conductivity (lambda), two novel weighted average models (WAMs) were developed in which soil solids represent the continuous phase. In the first model, WAM(s)-1, the continuous phase consists of two distinctive minerals groups (quartz and compounded remaining soil minerals), while air and water are treated as dispersed components. In the second model, WAM(s)-2, all soil minerals are compounded and considered the continuous phase, while air and water are dispersed components. In contrast to de Vries' original WAM with two continuous phases (soil air or soil water), the proposed models are very simple due to the following assumptions: using soil solids as a single continuous medium lead to eliminating the discontinuity of thermal conductivity when switching between soil air and soil water as continuous medium, and using the thermal conductivity of dry air simplifies a complex expression for an apparent thermal conductivity of humid soil air. Both models were successfully calibrated and validated using 39 Canadian Field Soil database and 3 Standard Sands and were successfully applied to 10 Chinese soils
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
On modelling the thermal conductivity of soils using normalized-multi-variable pedotransfer functions
No full textA comprehensive analysis of 6-published and 15-new Kersten (Ke) functions, i.e. normalized soil thermal conductivity (λ) expressions, was conducted using a complete λ data base of 40 Canadian soils. It was confirmed that Ke depended mainly on the degree of soil saturation (Sr), while additional dependency on volumetric content of sand (θsa) as the second variable and organic matter (θo-m) as the third variable , was marginal. Furthermore, a few Ke(Sr) functions did not fully meet the fundamental requirements at Sr boundaries, i.e. and . However, accurate λ estimates were still obtained within small Ke deviations, i.e. and . After applying a least square regression analysis to 21 functions, the following Ke(Sr) were found to be the highest ranking:
From the novel Ke functions, two earned notable attention, namely: the 1st and 3rd Ke functions from the above list. The former is an extension to full Sr range for the original model by Johansen, while the latter is a simple power-exponential function. The λ estimates obtained by the functions listed above closely followed experimental data of a majority of 40-Canadian soils and Standard Sands. Standard deviation (SD) was used to determine the predictive performance of the Ke(Sr) functions: 17-coarse soils SDave ≈ 0.19 W m−1 K−1, 22-fine soils SDave ≈ 0.11 W m−1 K−1, and Standard Sands SDave ≈ 0.16 W m−1 K−1.
In addition, the highest ranking functions, listed above, underwent validation against soil data from different places and dissimilar geneses. In general, the obtained estimates of λ closely follow experimental data: Chinese soils (SDave ≈ 0.160 W m−1 K−1), American soils (SDave ≈ 0.125 W m−1 K−1). However, uncertain λ estimates were obtained for soils of diverse geneses (volcanic origin)
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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