1,720,961 research outputs found
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
Об эволюционных обратных задачах для математических моделей тепломассопереноса
No full textS.G. Pyatkov, Yugra State University, Khanty-Mansiisk, Russian Federation,
[email protected].
Сергей Григорьевич Пятков, доктор физико-математических наук, профессор, Высшая цифровая школа, Югорский государственный университет (г. Ханты-
Мансийcк, Российская Федерация), [email protected] article is a survey. The results on well-posedness of inverse problems for
mathematical models of heat and mass transfer are presented. The unknowns are the
coefficients of a system or the right-hand side (the source function). The overdetermination
conditions are values of a solution of some manifolds or integrals of a solution with weight
over the spatial domain. Two classes of mathematical models are considered. The former
includes the Navier–Stokes system, the parabolic equations for the temperature of a fluid,
and the parabolic system for concentrations of admixtures. The right-hand side of the
system for concentrations is unknown and characterizes the volumetric density of sources
of admixtures in a fluid. The unknown functions depend on time and some part of spacial
variables and occur in the right-hand side of the parabolic system for concentrations. The
latter class is just a parabolic system of equations, where the unknowns occur in the righthand side and the system as coefficients. The well-posedness questions for these problems are examined, in particular, existence and uniqueness theorems as well as stability estimates for solutions are exposed. Представлены результаты о корректности обратных задач для математических моделей тепломассопереноса. Неизвестными являются правая часть в уравнении (функция источников) и коэффициенты уравнения. Условия переопределения – значения решения на некоторых многообразиях или в отдельных точках. Рассматриваются два класса математических моделей. Первая включает систему уравнений Навье – Стокса, дополненную параболическим уравнением для температуры и параболической системой для концентраций примесей. Правая часть неизвестна и характеризует объемную плотность источников в жидкости. Неизвестные функции зависят от времени и части пространственных переменных и входят в правую часть уравнения. Второй класс систем – параболическая система уравнений уравнений для концентраций переносимых веществ, где неизвестные входят как в правую часть так и саму систему в
качестве коэффициентов. Показана корректность этих задач, в частности полученные теоремы существования, единственности и оценки устойчивости для решений. Далее, мы опишем некоторые алгоритмы решения обратных задач о восстановлении точечных источников по точечным данным переопределения, основанные на асимптотике решений функций Грина соответствующих эллиптических задач.The author was supported by the Russian foundation for basic research (Grant 18-01-00620a)
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
Об обратных задачах с точечным переопределением для математических моделей тепломассопереноса
No full textS.G. Pyatkov, Yugra State University, Khanty-Mansiysk, Russian Federation,
[email protected]
Сергей Григорьевич Пятков, доктор физико-математических наук, профессор,
кафедра цифровых технологий, Югорский государственный университет (г. Ханты-
Мансийск, Российская Федерация), [email protected] article is a survey devoted to inverse problems of recovering sources and coefficients
(parameters of a medium) in mathematical models of heat and mass transfer. The main
attention is paid to well-posedness questions of the inverse problems with pointwise
overdetermination conditions. The questions of this type arise in the heat and mass transfer theory, in environmental and ecology problems, when describing diffusion and filtration processes, etc. As examples, we note the problems of determining the heat conductivity tensor or sources of pollution in a water basin or atmosphere. We describe three types of problems. The first of them is the problem of recovering point or distributed sources. We present conditions for existence and uniqueness of solutions to the problem, show non-uniqueness examples, and, in model situations, give estimates on the number of measurements that allow completely identify intensities of sources and their locations. The second problem is the problem of recovering the parameters of media, in particular, the heat conductivity. The third problem is the problem of recovering the boundary regimes, i. e. the flux through a surface or the heat transfer coefficient. Данная работа – обзор, посвященный обратным задачам восстановления источников и коэффициентов (параметров среды) в математических моделях тепломассопереноса. Главное внимание уделяется вопросам корректности обратных задач с точечными условиями переопределения. Такие вопросы возникают в теории тепломассопереноса, в задачах окружающей среды и экологии, при описании процессов диффузии, фильтрации и во многих других областях. Примерами могут служить задача определения тензора теплопроводности или задача определения источников загрязнения в водном бассейне или атмосфере. Мы рассматриваем три типа задач. Первая из них – задача восстановления точечных или распределенных источников. Описываются условия существования и единственности решений, приводятся примеры неединственности и, в модельных ситуациях, даются оценки на число замеров, которые позволяет полностью определить интенсивности источников и их местоположение. Вторая задача –
задача восстановления параметров среды например, теплопроводности. Третья задача – задача о восстановлении граничных режимов, т.е. потока через поверхность или коэффициента теплопередачи.This research was funded by the Russian Science Foundation and the government of Khanty-Mansiysk Autonomous Okrug – Yugra (Grant 22-11-20031)
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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