1,720,987 research outputs found
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
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
New relationships between spherical and spheroidal harmonics and applications
No full textThis thesis deals with solutions to Laplace's equation in 3D, finding new relationships between solutions, manipulating these to find new approaches to physical problems, and proposing a new class of solutions. We mainly consider spherical and prolate spheroidal geometry and their corresponding solutions - spherical and spheroidal solid harmonics. We first present new relationships between these, expressing for example spherical harmonics as a series of spheroidal harmonics. Similar relationships are known but we work with the spherical and spheroidal coordinate systems being offset from each other. We also propose a new class of solutions which we call logopoles which have many links with spherical and spheroidal harmonics, and are related to the potential created by simple finite line charge distributions. Through the logopoles we find another relationship between the spheroidal harmonics and the often discarded alternate spherical harmonics. Then we apply one of the new spherical-spheroidal harmonic relationships to problems involving a point charge/dipole outside a dielectric sphere. We find new solutions where the potential is expanded as a series of spheroidal harmonics instead of the standard spherical ones, and we show that the convergence is much faster. We also solve these problems with logopoles and the solutions converge even faster, although they are more complicated as they involve a combination of logopoles and spherical harmonics
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
Adsorption of dye molecules on metallic nanoparticles: Unraveling the origins of the modified spectral absorption
No full textThe enhanced optical response of molecules in the vicinity of metallic nanoparticle is the basis for many surface enhanced spectroscopies and of interest to the field of plasmonics. However, the mechanisms behind the enhancement are still a matter of debate because of the interplay between electromagnetic and chemical effects, which complicates the interpretation of spectral changes. Our ability to measure the surface absorption of dyes from very low coverage to high coverage allows us to identify the con- tribution of each effect (dye-dye interaction and dye-particle interaction) to the spectral modifications. In the course of this investigation, we also measured the adsorption isotherms of dyes in the presence of halide ions, which provides a detailed insight into the adsorption process on silver colloids
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
Synthesis and Characterization of Light-Emitting Magnetic Bi-Functional Nanocrystals
No full textThe combination of two different materials into a single nanostructure is of great interest due to the potential in creating structures where two distinct properties are displayed in a single composite nanostructure. This can be achieved by combining two types of materials, each having a distinct property, through interfaces in various spatial configurations, such as those of core-shells and heterodimers.
Self-assembly of these composite nanostructures into thin films and bulk materials could lead to hybrid materials with enormous design flexibility, structural complexity and multifunctionality. These hybrid materials may have great potential in applications in various fields, including biomedical applications, catalysis of organic reactions, energy generation and conservation and other industrial applications.
The focus of this thesis is the solution phase synthesis of hybrid nanostructures made of magnetic and semiconductor materials, which can lead to potentially bi-functional nanostructures. A seeded growth approach was employed in synthesizing these hybrid nanostructures, where magnetic seed particles were synthesized in the first step and the fluorescent semiconductor material was grown on the magnetic seeds in the second step. The morphology, crystal structure, crystallinity and chemical composition of the synthesized nanostructures were studied through transmission electron microscopy (TEM), selected area electron diffraction (SAED), energy dispersive X-ray spectroscopy (EDS) and powder X-ray diffraction (XRD). Optical characterizations such as UV-Vis spectroscopy and photoluminescence measurements as well as magnetic measurements were carried out on selected samples.
Chapter 1 and 2 introduced the background of this thesis and the experimental methods used in this research. The magnetic components involved included spherical nickel nanoparticles of 40, 20 and 10nm in size, nickel nanocubes (13nm) and iron oxide nanocubes (15nm). The semiconductor components involved included CdSe, CdS and CdTe.
In Chapter 3, 4 and 5, the synthesis and characterization of core-shell nanostructures involving the above magnetic and semiconductor materials were presented. The factors governing the formation of semiconductor shell layers on the surface of the magnetic seeds were investigated. In particular, the surface properties of the magnetic seeds played a dominant role in the formation of the semiconductor shell layers. In addition, the reactivity of the reagents used can affect the chemical composition and the morphology of the resultant core-shell structures.
In Chapter 6, analysis of high resolution TEM images was carried out on selected samples of semiconductor coated nickel nanoparticles. Through studying the crystallographic facets of Ni and CdSe, the presence of preferential orientation between the Ni and CdSe phases was identified and determined. This analysis resulted in further understanding of the growth behavior of the semiconductor components on the nickel cores.
These result chapters are followed by Chapter 7, which is the conclusion chapter. Also included in the conclusion chapter is potential future work of this research
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