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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
Оптичні властивості “анізотропної” квантової точки
Get PDFThe optical properties of an “anisotropic” semiconductor nanodot – a nanoscale object in the form of a rectangular parallelepiped - with sides a ≠ b ≠ c are considered. Such dimensions are closely related to the values of the effective masses of the electron. The analysis of the spectral dependence of the absorption coefficient a(w) under different degrees of "anisotropy" and under different polarizations of the electromagnetic wave is carried out. The cases of the most intense optical transitions, i.e. between electronic states separated by the Fermi level, are analyzed. The obtained results indicate that 1) a(w) is of line structure, and 2) the positions of the peaks of a(w) in identical optical transitions in the isotropic nanodot and in the “anisotropic” ones coincide qualitatively. However, different masses in the “anisotropic” nanodot lead to a shift to the left or right of the peaks relative to identical peaks in the isotropic nanodot with simultaneous splitting of its degenerate peaks. Such shifts and their magnitudes are determined both by the degree of anisotropy (i.e. by the ratio between the effective masses), and by the polarization of light. It is pointed out that modern achievements in the creation of ordered semiconductor materials with nanoobjects of different shapes and sizes in nanostructures allows us to consider polarized electromagnetic wave as an effective factor in achieving the desired physical characteristics.Розглянуто оптичні властивості “анізотропного” напівпровідникової наноточки – нанорозмірного об\u27єкта у вигляді прямокутного паралелепіпеда – зі сторонами a ≠ b ≠ c. Такі розміри тісно пов\u27язані зі значеннями ефективних мас електрона. Здійснено аналіз спектральної залежності коефіцієнта поглинання a(w) при різних ступенях “анізотропії” та при різних поляризаціях електромагнітної хвилі. Проаналізовано випадки найбільш інтенсивних оптичних переходів, тобто між електронними станами, розділеними рівнем Фермі. Отримані результати вказують на те, що 1) a(w) має лінійчасту структуру, а 2) положення піків a(w) однакових оптичних переходів ізотропних наноточках та в “анізотропних” якісно збігаються. Однак різні маси в “анізотропній” наноточці призводять до зсуву ліворуч або праворуч від піків відносно однакових піків в ізотропній наноточці з одночасним розщепленням його вироджених піків. Такі зсуви та їх величини визначаються як ступенем анізотропії (тобто співвідношенням між ефективними масами), так і поляризацією світла. Показано, що сучасні досягнення у створенні впорядкованих напівпровідникових матеріалів з нанооб’єктами різної форми та розміру в наноструктурах дозволяють розглядати поляризовану електромагнітну хвилю як ефективний фактор досягнення бажаних фізичних характеристик
Особенности электрон-электронного взаимодействия в квантово-размерных объектах
No full textIn the Hartree-Fock approximation peculiarities of the effect of electron-electron interactions in a
quantum-dimensional object are analyzed. It is established that a self-energy Σn has the sawtooth dependence
on the Fermi level position or on the size of an object as a result of the size quantization effect.
The smaller the size of nano-objects, the more pronounced oscillations of Σn . And secondly, the smaller
the size of nano-objects, the less the electron-electron interaction.В роботі проаналізовано особливості електрон-електронної взаємодії в квантово-розмірних об’єктах
в наближенні Хартрі-Фока. Встановлено, що власна енергія Σn має пилоподібну залежність від положення рівня Фермі чи від розміру об’єкту, як прояв розмірного квантування. По-перше, чим менший розмір нанооб’єктів тим більш виразні осциляції Σn. І, по-друге, чим менший розмір нанооб’єктів, тим менша електрон-електронна взаємодія.В работе проанализировано особенности электрон-электронного взаимодействия в квантоворазмерных объектах в приближении Хартри-Фока. Установлено, что собственная энергия Σn имеет
пилообразную зависимость от положения уровня Ферми или от размера объекта как проявление размерного квантования. Во-первых, чем меньший размер нанообъектов тем более виражные осцилляции Σn. И во-вторых, чем меньший размер нанообъектов, тем меньше электрон-электронное взаимодействие
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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