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Модифікована модель агрегованої мертвої зони на прикладах переносу радіонуклідів у природних гідродинамічних системах
Get PDFThis paper presents the results obtained during a detailed study of the aggregate dead zone model designed to describe the longitudinal transport and dispersion of dissolved substances in a channel flow. This model is based on a new approach to the description of advection and dispersion, which allows to adequately reproduce the concentrations of solutes observed in natural hydrodynamic systems with a high degree of accuracy. Instead of modelling the dissolved solute concentration continuously in both distance and time along the watercourse, the aggregate dead zone model uses a black box approach and considers the concentration at the chamber outlet (from the aggregate dead zone) as a function of the concentration at the chamber inlet and the current time. This approach significantly reduces the computational time and reduces the requirements for the amount of initial and boundary data. The mathematical apparatus of the extended model of the aggregated dead zone is presented, designed to analyse the transport of non-conservative radioactive contamination in real water bodies, taking into account the possible interaction of the radionuclide with suspended sediments and a layer of bottom sediments. The equations of the proposed model are a system of ordinary differential equations with a delayed argument. The results of modelling the distribution of 3 H as a result of releases from 14 nuclear reactors in the Russian section of the Loire River for six months with an hourly discreteness are presented. The results of modelling the propagation of sudden 90Sr releases in the Kyiv reservoir, which occurred in 1999 as a result of the Chornobyl disaster, are presented. The modelling was carried out with a daily discreteness. A comparison of the obtained model values of radionuclide concentrations and measurement data was carried out. The proposed model has a comparative simplicity, much lower requirements for the amount of initial and boundary data, and very little time required for calculations.Prombles in programming 2024; 2-3: 45-52У роботі представлено результати, отримані під час детального дослідження моделі агрегованої мертвої зони, призначеної для опису поздовжнього перенесення і розсіювання розчинених речовин у русловому потоці. Ця модель ґрунтується на новому підході до опису адвекції та дисперсії, який дає змогу адекватно відтворювати спостережувані у природних гідродинамічних системах концентрації розчинених речовин із високим ступенем точності. Замість того, щоб моделювати концентрацію розчиненої речовини безперервно як за відстанню, так і за часом уздовж водотоку, модель агрегованої мертвої зони використовує підхід "чорної скриньки" і розглядає концентрацію на виході камери (з агрегованої мертвої зони) як функцію концентрації на вході камери та поточного часу. Такий підхід значно скорочує час обчислень і зменшує вимоги до обсягу вихідних і граничних даних. Наведено математичний апарат розширеної моделі агрегованої мертвої зони, призначеної для аналізу транспортування неконсервативного радіоактивного забруднення в реальних водних об'єктах, з урахуванням можливої взаємодії радіонукліда зі зваженими намулами і шаром донних відкладень. Рівняння запропонованої моделі складають систему звичайних диференційних рівнянь із запізнілим аргументом. Показано результати моделювання поширення 3 H в результаті викидів від 14 ядерних реакторів у русловій ділянці р. Луара протягом півроку із щогодинною дискретністю. Наведено результати моделювання розповсюдження різких викидів 90 Sr у Київському водосховищі, що мали місце в 1999 р. внаслідок Чорнобильської катастрофи. Моделювання виконано з добовою дискретністю. Проведено порівняння отриманих модельних значень концентрацій радіонуклідів і даних вимірювань. Запропонована модель має порівняльну простоту, значно менші вимоги до кількості початкових і граничних даних, дуже короткий час, необхідний для проведення розрахунків.Prombles in programming 2024; 2-3: 45-5
Modified model of the aggregated dead zone on examples of radionuclide transfer in natural hydrodynamic systems
Get PDFThis paper presents the results obtained during a detailed study of the aggregate dead zone model designed to describe the longitudinal transport and dispersion of dissolved substances in a channel flow. This model is based on a new approach to the description of advection and dispersion, which allows to adequately reproduce the concentrations of solutes observed in natural hydrodynamic systems with a high degree of accuracy. Instead of modelling the dissolved solute concentration continuously in both distance and time along the watercourse, the aggregate dead zone model uses a black box approach and considers the concentration at the chamber outlet (from the aggregate dead zone) as a function of the concentration at the chamber inlet and the current time. This approach significantly reduces the computational time and reduces the requirements for the amount of initial and boundary data. The mathematical apparatus of the extended model of the aggregated dead zone is presented, designed to analyse the transport of non-conservative radioactive contamination in real water bodies, taking into account the possible interaction of the radionuclide with suspended sediments and a layer of bottom sediments. The equations of the proposed model are a system of ordinary differential equations with a delayed argument. The results of modelling the distribution of 3 H as a result of releases from 14 nuclear reactors in the Russian section of the Loire River for six months with an hourly discreteness are presented. The results of modelling the propagation of sudden 90Sr releases in the Kyiv reservoir, which occurred in 1999 as a result of the Chornobyl disaster, are presented. The modelling was carried out with a daily discreteness. A comparison of the obtained model values of radionuclide concentrations and measurement data was carried out. The proposed model has a comparative simplicity, much lower requirements for the amount of initial and boundary data, and very little time required for calculations.Prombles in programming 2024; 2-3: 45-5
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
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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