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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
Apple sawfly (Hoplocampa testudinea, Klug) situation, forecasting, monitoring and use of extract from Quassia amara for controlling the apple sawfly in organic apple orchards in Sweden
Get PDFThe main objective of the thesis was to find out the growers’ perspective towards the problem of apple sawfly (Hoplocampa testudinea, Klug) as well as its solution, evaluate the suitability of Dutch and Swiss forecasting methods in Swedish environment, and evaluate the efficiency and timing of Quassia extract application with varying concentration of rapeseed oil product Zence 40 against the apple sawfly. The apple sawfly was monitored using white sticky traps in two orchards located in Alnarp and Malmö. The forecasting models for emergence of first sawfly (Dutch model) and egg hatch (Swiss model) were combined and used for determining timing of Quassia extract application. The model worked well for forecasting both the first emergence and egg hatch of the apple sawfly. A field trial was conducted for spraying Quassia extract as a control measure against the apple sawfly. The treatments were 1) Petal fall (PF), 2) Day degree low zence (DDL), 3), Day degree high zence (DDH) and 4) Control (C). The dose of Quassia was used at 12 kg per hectare in 400 liters of water. The percentage of the apple sawfly damage was significantly lower in all treatments compared to control with 3.8%, 3.2%, 2.9% and 9.9 % damage in treatment 1, 2, 3 and 4. There was no difference in secondary damage between treatments. This could have been influenced by a large aphid infestation at that time. Semi structured face to face interviews were carried out to get deeper understanding of the problem. Older orchards were found to have relatively more infestation compared to new orchards. The growers were interested to continue the work with monitoring and trap catches in the coming season. They wished that the model should be proposed which can be used by the advisors from Äppelriket and the Board of Agriculture for forecasting the apple sawfly in Sweden
MAGNETOCALORIC EFFECT IN OXIDE MATERIALS
Get PDFThe magnetocaloric effect (MCE) is the heating or cooling of a magnetic material due to the application of a magnetic field. Magnetic refrigeration (MR) based on the MCE is a promising alternative to conventional gas compression-based cooling techniques. Because of the increased interest in these materials over the last two decades, less expensive materials, such as garnet and perovskite oxides, have been investigated as possible MC materials by altering their microstructure. In this view, the motivation for this work is to explore the effect of impurity atoms in these oxides from the technological and scientific point of view and highlight the general consequences on the magnetic and magnetocaloric properties of these compounds. The work presents a detailed characterization of the structural, magnetic, and magnetocaloric properties of three oxide systems, namely (1) lanthanum strontium magnetite perovskite composites, (2) aluminum-doped gadolinium garnets, and (3) rare-earth-doped gadolinium garnets. All compounds were prepared a facile one-step autocombustion process. Structure-property relation in the studied compounds was established via various analytical techniques, including x-ray diffraction, scanning electron microscopy, Fourier transformed infrared spectroscopy, Mossbauer spectroscopy, physical property measurement system, and density functional theory (DFT). The presence of antiferromagnetic MO phase in (1-x) La0.45Nd0.25Sr0.30MnO3 (LSMO ) – x Wt.% MO (M = Cu, Co, and Ni) nanocomposites brings in a second-order magnetic phase transition in the LSMO phase. Consequently, La0.45Nd0.25Sr0.3MnO3 - 2.5 Wt.%CuO composite displayed a maximum entropy change (ΔSM) ~ -4.0 J/kg/K, highest among studied composites, and is 110% higher than that obtained with La0.45Nd0.25Sr0.3MnO3. La0.45Nd0.25Sr0.3MnO3–5.0 Wt.%NiO displayed the highest relative cooling power (RCP) value ~ 299 J/kg among all studied composites. The magnetic changes in the composite are ascribed to alteration of Mn3+-O2—Mn4+ superexchange interaction strength due to M ion migration within and the surface of LSMO grain. Magnetization of aluminum-doped Gd3Fe5-xAlxO12 (0.0 ≤ x ≤ 1.0) compound enhanced with non-magnetic aluminum ion replacing magnetic iron ions with the spin-down moment. Consequently, the maximum magnetic entropy change, derived from magnetic isotherms in field up to 3 T, in Gd3Fe5-xAlxO12, was observed to vary from ~1.94 to ~3.07 J. K-1 kg-1 for x = 0.0 and x = 1.0, respectively. While an RCP value of 226 J.kg-1 was measured for x = 0.25 sample. Furthermore, the study was extended to understanding the influence of rare-earth ion doping in Gd3-xRExFe5O12 (RE = Y, Nd, Sm, and Dy, x = 0.00, 0.25, 0.50, and 0.75). At low temperature, the Gd3+ (L = 0) spin moment couples positively with the Fe3+ site moment, increasing the magnetization value of the compound. The presence of rare-earth ions with a finite orbital moment, such as Nd3+, Sm3+, and Dy3+, affects the RE3+(Nd, Sm, Dy)- O2- - Fe3+(Tetra.) bond-angle and bond-length in favor of enhancing the superexchange interaction with Fe3+ (tetrahedral site, spin-down). Consequently, RE3+ spins align opposite to the net spin moments of Fe3+ sites, leading to a decrease in magnetization value at low temperatures. Maximum entropy change, ΔSMmax, increased with Dy3+ and Sm3+ doping, whereas Nd3+ and Y3+ decreased ΔSM with x content. Moreover, the maximum magnetic entropy change value, ∆S_M^Max, increased ~ 7% for Dy3+ x = 0.75. These values are relatively high and comparable to some noticeable magnetocaloric materials. The findings in these studies show that a careful choice of dopants can be used to tune the structure-property relation toward enhancing the MCE in the studied compounds. The study will help the community working in the field of MC materials with a fundamental understanding of the underlying structure-property of materials to futuristic engineering of novel MC materials
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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