1,721,153 research outputs found
Constraining a 2D density-dependent saltwater intrusion model using electrical imaging data
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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
Regional flow in a complex coastal aquifer system: combining voxel geological modelling with regularized calibration
No full textLow-lying coastal regions are often highly populated, constitute sensitive habitats and are at the same time exposed to challenging hydrological environments due to surface flooding from storm events and saltwater intrusion, which both may affect drinking water supply from shallow and deeper aquifers. Near the Wadden Sea at the border of Southern Denmark and Northern Germany, the hydraulic system (connecting groundwater, river water, and the sea) was altered over centuries (until the 19th century) by e.g. the construction of dikes and drains to prevent flooding and allow agricultural use. Today, massive saltwater intrusions extend up to 20 km inland. In order to understand the regional flow, a methodological approach was developed that combined: (1) a highly-resolved voxel geological model, (2) a ∼1 million node groundwater model with 46 hydrofacies coupled to rivers, drains and the sea, (3) Tikhonov regularization calibration using hydraulic heads and average stream discharges as targets and (4) parameter uncertainty analysis. It is relatively new to use voxel models for constructing geological models that often have been simplified to stacked, pseudo-3D layer geology. The study is therefore one of the first to combine a voxel geological model with state-of-the-art flow calibration techniques. The results show that voxel geological modelling, where lithofacies information are transferred to each volumetric element, is a useful method to preserve 3D geological heterogeneity on a local scale, which is important when distinct geological features such as buried valleys are abundant. Furthermore, it is demonstrated that simpler geological models and simpler calibration methods do not perform as well. The proposed approach is applicable to many other systems, because it combines advanced and flexible geological modelling and flow calibration techniques. This has led to new insights in the regional flow patterns and especially about water cycling in the marsh area near the coast based on the ability to define six predictive scenarios from the linear analysis of parameter uncertainty. The results show that the coastal system near the Danish-German border is mainly controlled by flow in the two aquifers separated by a thick clay layer, and several deep high-permeable buried valleys that connect the sea with the interior and the two aquifers. The drained marsh area acts like a huge regional sink limiting submarine groundwater discharge. With respect to water balance, the greatest sensitivity to parameter uncertainty was observed in the drained marsh area, where some scenarios showed increased flow of sea water into the interior and increased drainage. We speculate that the massive salt water intrusion may be caused by a combination of the preferential pathways provided by the buried valleys, the marsh drainage and relatively high hydraulic conductivities in the two main aquifers as described by one of the scenarios. This is currently under investigation by using a salt water transport model
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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