1,721,073 research outputs found
Water Figures: quarterly newsletter of the International Water Management Institute (IWMI).
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Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
The evaluation of surge flow in border irrigation (with special reference to cracking soils)
No full text© 1993 Dr. Hugh TurralSurge flow was identified as a potential method of improving farm water management to both reduce water use and minimise accessions to water table, and therefore to help address the salinity and water-logging problems facing the irrigated areas of the Murray-Darling Basin.
Surge flow has been intensively researched in furrow irrigation in the USA, but border strips (which are the dominant application method in south-eastern Australia) and cracking soils have received minimal attention.
This study investigated surge response in border irrigation with particular reference to cracking clay soils. Two years' field work resulted in a substantial data set covering four soil types and a range of management options. Surge flow reduces water use on cracking clays by 15-40% compared with continuous irrigation under similar conditions and given the same level of management. A negative response was observed on homogenous fine sandy loams, with up to 30% more water applied in surge flow.
The positive response was obtained over a range of cycle ratios from 0.2-0.5 and with off-times from 30-300 minutes. Measured soil moisture distributions in the second season showed that application uniformity was better using long offtimes of around 300 minutes. Calculations of the water balance indicate that a greater proportion of applied water is retained in the root zone in surge flow and accessions are a small proportion of those in conventional irrigation.
The strong field response was not supported by infiltration test data which recorded greater water intake in surge flow than in continuous tests. The recirculating infiltrometer over-estimated cumulative infiltration for both surge and continuous application, in both seasons.
It was later observed that water advances in subsurface cracks in the off-time, up to 70 m ahead of the surface stream. Additional analysis indicates that the surge response is largely due to a mechanism connected with this phenomenon, which helps reconcile the disagreement between field and infiltration test data.
Surges overlapped in every test and this phenomenon cannot be simulated by existing hydraulic models of surge flow and substantial revisions are needed before meaningful calibration can be undertaken.
The field work provided a clear statement of the difficulty of obtaining infiltration data on cracking soils, and highlights the need for effective real-time estimation of infiltration parameters to overcome severe temporal and spatial variability in infiltration conditions.
An inverse solution of the Zero Inertia model was developed, using a constrained Simplex optimisation algorithm to determine infiltration and roughness parameters from advance and depth profile data plus a compound objective function of the two. Global parameters, with reasonably effective predictive performance, were obtained using a compound objective function with continuous flow data sets and, more tentatively, for surge flow. This work provides practical possibilities for automation of border irrigation, using as little as two sensors to determine one roughness and one infiltration parameter from advance data, providing the Kostiakov exponent can be reliably classified. A minimum offour sensors are needed to identify two Simple Kostiakov infiltration parameters and one roughness value. Longer term, farm-scale trials are now required
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe 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
Full text linkWe 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
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