bluuebunny/crossref_metadata_2025_split huggingface dataset:
A software package for the simulation of fluid flows in discrete fracture networks with vugs
Authors: Блонский А.В. 
Published: August 2021

Представлен программный комплекс для математического моделирования течений в дискретных системах трещин. Описана математическая модель течения, приведено краткое изложение вычислительных алгоритмов и сформулированы особенности программной реализации. Рассмотрена структура разработанного программного комплекса, обсуждаются аналогичные программные комплексы и указаны их отличия от представленного в настоящей статье. На ряде задач продемонстрирована работоспособность предложенных в статье математической модели, алгоритмов и программного комплекса.
A software package for the mathematical simulation of fluid flows in discrete fracture networks is proposed. The mathematical model of flows is analyzed, a brief description of the computational algorithms is given, and the features of software implementation are formulated. The structure of the developed software package is considered, a number of similar software packages are discussed, and their differences from the proposed one are shown. A number of model problems are solved to demonstrate the efficiency of the proposed mathematical model, algorithms, and software implementation.
Taking account of the hysteresis effects in the calculation of eddy currents
Authors: Ступаков И.М. , Рояк М.Э. , Кондратьева Н.С. , Зеленский А.В. , Винокуров Н.А. 
Published: August 2021

Рассматривается подход, позволяющий при численном моделировании электромагнитных процессов одновременно учитывать как остаточную намагниченность, так и вихревые токи. Работоспособность разработанного метода верифицируется путем сравнения с результатами экспериментальных измерений для магнита с О-образным магнитопроводом.
An approach that allows one to take into account the residual magnetization and the eddy currents simultaneously during the numerical simulation of electromagnetic processes is considered. The efficiency of the proposed approach is verified by comparing with the results of experimental measurements for a magnet with an O-shaped magnetic core.
A Cartesian grid method for the three-dimensional numerical simulation of shock wave propagation in complex-shape domains with moving boundaries
Authors: Елесин В.В. , Сидоренко Д.А. , Уткин П.С. 
Published: August 2021

Статья посвящена разработке и количественной оценке свойств вычислительного алгоритма метода декартовых сеток для трехмерного математического моделирования распространения ударных волн в областях сложной изменяющейся формы. Представлено подробное описание вычислительного алгоритма, ключевым элементом которого является определение численного потока через грани, по которым внутренние, регулярные ячейки расчетной области соседствуют с внешними, пересекаемыми границами тел ячейками. Работоспособность алгоритма продемонстрирована в результате сравнения рассчитанных и экспериментальных данных в задачах о взаимодействии ударной волны с неподвижной сферой и подвижной частицей.
This paper is devoted to the development and quantitative estimation of a numerical algorithm based on the Cartesian grid method for the threedimensional mathematical simulation of shock wave propagation in domains of complex varying shapes. A detailed description of the numerical algorithm is presented. Its key element is the specification of numerical fluxes through the edges that are common for the inner regular cells of the computational domain and the outer cells intersected by the boundaries of the bodies. The efficiency of the algorithm is shown by comparing the numerical and experimental data in the problems of interaction of a shock wave with a fixed sphere and a moving particle.
Application of asymptotic analysis methods for solving a coefficient inverse problem for a system of nonlinear singularly perturbed reaction-diffusion equations with cubic nonlinearity
Authors: Лукьяненко Д.В. , Мельникова А.А. 
Published: August 2021

Продемонстрированы возможности методов асимптотического анализа в применении к решению коэффициентной обратной задачи для системы нелинейных сингулярно возмущенных уравнений типа реакциядиффузия с кубической нелинейностью. Рассматриваемая в статье задача для системы уравнений в частных производных сводится к гораздо более простой для численного исследования системе алгебраических уравнений, которая связывает данные обратной задачи (информацию о положении фронта реакции во времени) с коэффициентом, который необходимо восстановить. Численные эксперименты подтверждают эффективность предложенного подхода.
The capabilities of asymptotic analysis methods for solving a coefficient inverse problem for a system of nonlinear singularly perturbed equations of reactiondiffusion type with cubic nonlinearity are shown. The problem considered for a system of partial differential equations is reduced to a system of algebraic equations that is much simpler for a numerical study and relates the data of the inverse problem (the information on the position of the reaction front in time) with the coefficient to be recovered. Numerical results confirm the efficiency of the proposed approach.
A modified simplex embedding method for solving convex optimization problems with a large amount of constraints
Authors: Колосницын А.В. 
Published: August 2021

Рассматривается метод симплексных погружений, адаптированный для решения задач выпуклой оптимизации с большим числом ограничений. Разработаны две модификации, позволяющие ускорять работу метода. Первая из них использует более экономичный способ расчета невязок ограничений, что позволяет существенно сокращать время работы алгоритма в случае большой размерности задачи. Вторая модификация основана на возможности метода определять неактивные ограничения задачи. Представлены результаты вычислительных экспериментов с использованием модифицированных версий метода симплексных погружений при решении тестовых задач квадратичной и выпуклой недифференцируемой оптимизации.
A simplex embedding method adapted for solving convex optimization problems with a large amount of constraints is considered. Two modifications of the method are proposed for better performance. First of them uses a more economical approach to the residual computation for constraints, which allows one to significantly reduce the execution time of the algorithm in the case of a large amount of constraints. One of the important peculiarities of the simplex embedding method is its ability to find inactive constraints. This property of the method is used as the basis for its second modification. The numerical results obtained when solving a number of quadratic and convex nondifferentiable optimization problems show the efficiency of the proposed modifications.
Algorithms for the computer simulation of ultrafast photoinduced intermolecular charge transfer in liquids
Authors: Феськов С.В. , Хохлова С.С. 
Published: August 2021

Предложены подходы к численному решению систем уравнений, описывающих кинетику двухстадийной фотохимической реакции в вязком полярном растворителе. Математическая модель построена на основе расширенной интегральной теории встреч и учитывает диффузионную подвижность молекул-реагентов в жидкости, неравновесность среды и внутримолекулярных степеней свободы, удаленный перенос электрона в донорно-акцепторных парах, разделенных растворителем. В рамках метода броуновского моделирования разработаны алгоритмы расчета безреакционных стохастических траекторий частиц на поверхностях свободной энергии, соответствующих различным состояниям реагентов и продуктов, схемы детектирования реакционных событий и генерации электронных прыжков, а также алгоритмы расчета нестационарных потоков частиц между электронными состояниями и вычисления интегральных ядер кинетических уравнений. Представлены результаты тестовых расчетов, демонстрирующие корректность численного решения и воспроизводящие известные особенности реакций электронного переноса в полярных жидкостях.
Efficient approaches to the numerical solution of equations describing the kinetics of two-stage photochemical reactions in a viscous polar solvent are proposed. The mathematical model is based on the extended integral encounter theory and takes into account diffusive mobility of reactants in solution, nonequilibrium of solvent and intramolecular degrees of freedom, and remote electron transfer in solvent-separated donor-acceptor pairs. In the framework of the Brownian simulation technique, a number of numerical algorithms for calculating unreactive stochastic trajectories of particles on free energy surfaces corresponding to different electronic states of reactants and products are suggested, some computational schemes for the detection of reaction events and the generation of electronic hops are developed, and algorithms for calculating the time-dependent reaction fluxes between the electronic states and integral kernels of the kinetic equations are implemented. The results of test simulations demonstrating the validity of the numerical solutions and reproducing well-known features of electron transfer reactions in polar solvents are discussed.
An algorithm for packing balls of two types in a three-dimensional set
with a non-Euclidean metric
Authors: Казаков А.Л. , Лемперт А.А. , Та Ч.Т. 
Published: August 2021

Рассматривается задача упаковки шаров двух типов в замкнутое ограниченное множество в трехмерном пространстве как с евклидовой, так и со специальной неевклидовой метрикой. Требуется максимизировать радиус шаров при известном количестве шаров каждого типа и заданном отношении между радиусами. Предложен вычислительный алгоритм, основанный на комбинации метода бильярдного моделирования и оптико-геометрического подхода, базирующегося на фундаментальных физических принципах Ферма и Гюйгенса. Приведены результаты вычислительного эксперимента.
The problem of packing balls of two types into a closed bounded set in three-dimensional space with the Euclidean metric and a special non-Euclidean metric. It is required to maximize the radius of the balls for a given number of balls of each type and a known ratio of radii. We propose a computational algorithm based on a combination of the billiard modeling method and the optical-geometric approach employing the fundamental physical principles of Fermat and Huygens. The results of numerical experiments are discussed.
Allocation of three brightness levels on a noisy image
Authors: Лихачев А.В. 
Published: August 2021

Предложен новый метод восстановления изображений, имеющих три неизвестные градации яркости. Для их определения используются фрагменты изображения, гистограммы которых согласуются с заданным распределением шума. Далее все пиксели распределяются по найденным уровням яркости посредством бинарной классификации. Выполнен вычислительный эксперимент, по результатам которого оказалось, что ошибка оценки исходных яркостей не превысила 3%. При относительно низком уровне шума доля неверно классифицированных пикселей от их общего числа составила менее 0.006.
A new recovery method for images with three unknown brightness levels is proposed. In order to determine these levels, we use the image fragments whose histograms correspond to a given noise distribution. All pixels are distributed over the found brightness levels by a binary classification. The numerical results show the error in the estimate of the original brightnesses is no more than 3%. When the noise level is relatively low, the fraction of wrong classified pixels in their total amount is less than 0.006.
Trajetória docente na transição e na apropriação de tecnologias digitais em práticas de ensino
Authors: Beraldo Rossana Mary Fujarra 
Published: August 2021

Este estudo enfocou a apropriação de tecnologias digitais por duas professoras como instrumento de ensino e instrução em escola de ensino médio. Temos interesse na trajetória docente na transição de práticas tradicionais para contextos híbridos de aprendizagem. Utilizamos métodos mistos a partir da Grounded Theory e aporte da Teoria da Atividade e abordagem dialógica. Optamos pela pesquisa qualitativa com entrevista em áudio, fonte documental e observações de interações entre estudantes em contexto híbrido de aprendizagem. Os resultados indicaram que a trajetória docente perpassa pela apropriação tecnológica na: a) convencionalização de um campo simbólico e semiótico no qual as práticas mediadas por recursos digitais passam pela generalização do objeto na/pela atividade coletiva; b) integração dos instrumentos digitais como um corpo de conhecimentos que podem ser aplicados em tarefas situadas e orientadas para metas.
Las narrativas autobiográficas en la construcción de la experiencia y el sí mismo
Authors: González María Fernanda 
Published: August 2021

El articulo ofrece una explicación semiótica y psicogenética sobre cómo las narrativas autobiográficas organizan las experiencias y dan un sentido de continuidad al yo. Las narrativas son actuaciones comunicativas que se articulan en dos direcciones complementarias. Por un lado participan en la interpretación y construcción de significados sobre una situación y por el otro dan sentido a la propia actuación. Desde ese punto de vista puede comprenderse cómo se construye ”“ de modo mediado y dialógico- la identidad narrativa, lo que lleva a la apreciación ética y estética de las actuaciones propias y del sí mismo.
Alfabetização científica e a construção de concepções na contexto de formação de professores
Authors: Sessa Patrícia da Silva , Paiva Júlio Carvalho de , Casasco Emile Ferreira da Cunha , Silva João Rodrigo Santos da 
Published: August 2021

O presente artigo investiga as concepções sobre Alfabetização Científica (AC) de professores de Ciências de 6º ao 9º ano da rede pública de um município do interior paulista em um contexto de formação continuada. Os dados foram coletados através de um questionário com perguntas abertas sobre a atividade da formação, as concepções dos professores antes e depois dessas atividades. Como resultados, alguns professores apresentaram mudanças de suas concepções sobre Alfabetização Científica no que diz respeito Ã necessidade de métodos científicos, nos permitindo apontar a necessidade de continuidade de pesquisas que contemplem esse tipo de abordagem bem como as formações continuadas de professores
Desafios à inclusão dos alunos com deficiência auditiva numa aula de matemática
Authors: Cruz-Santos Anabela , Martinho Maria Helena 
Published: August 2021

Este artigo procura responder ao desafio de pensar a inclusão de alunos com Deficiência Auditiva em uma aula de Matemática. Nesse sentido, contrariamos o olhar simplista de ver o trabalho dos diferentes profissionais envolvidos sem que seja estabelecida uma coordenação entre eles. Ademais, propomos um conjunto de práticas de ensino para ajudar os professores de Matemática e o intérprete a enfrentarem as dificuldades inerentes à inclusão de alunos com Deficiência Auditiva na aula de Matemática e, em particular, desafiamos o desenvolvimento do trabalho colaborativo entre a equipe profissional envolvida.
First monument of stone architecture in Belarus, created in the Romanesque building tradition
Authors: Trusov O. A. 
Published: August 2021

The article for the ﬁrst time proposed a new version of the origin of masters who were invited to build the Minsk temple. The article says that the masters could be invited from Germany (Saxony), and not from Poland, as previously thought.In 1949–1951 the archaeologist Vasil Tarasenka found the ruins of an unﬁnished temple on the territory of Minsk Castle (later this monument was studied by E. Zagarulsky, G. Shtykhaŭ and A. Miadzvedzeŭ). The foundation and lower parts of the walls of the temple are made of stone and are squared with stone tiles of a rectangular shape on a mortar. The masonry technique is Romanesque, characteristic of Western European architecture.The main controversy is the time of construction of the temple. Some researchers believe that this is the second half of the XI century, others believe that the ﬁrst Minsk appanage prince Gleb began the construction at the beginning of the XII century.Based on Romanesque construction methods, it is believed that Polish craftsmen built the temple. The author for the ﬁrst time expresses and justiﬁes the German (Saxon) origin of the builders of the temple in Minsk.
Problem of language interference in literature and its impact on speech сommu nication
Authors: Patapava N. L. 
Published: August 2021

The article highlights the evolution of linguistic views on the phenomenon of interference. The problems of interference have been worrying a large number of scientists both in our country and abroad for several decades since the last century. The research in the ﬁeld of language systems interference continues in all directions nowadays. However, a number of its aspects remain poorly understood. The relevance of the language interference study is connected with the emergence and study of new concepts, such as linguistic interference, as well as translation, textual, sociocultural, cross-cultural, terminological interference.Having studied the views of the scientists on the problem of language interference in this article, we can conclude that bilingualism and language contact are necessary conditions for the manifestation of interference. The place of manifestation of linguistic interference is the person himself, communicating in a foreign language or translating from one language to the other when he is trying to compensate for some elements, phenomena and functions of one language system with elements, phenomena and functions from the other one, which can lead to accent, literalism, distortion of meaning and to various deviations from the original, but also in some cases can help with communication or translation.The need to study, systematize and develop the recommendations for overcoming and using the phenomenon of interference in a professionally oriented translation is not in doubt. At present, the internationalization of higher education is of fundamental importance. Personal experience in the process of studying and teaching foreign languages shows that the phenomenon of interference must be approached consciously: interference must be studied and understood in detail in order to subsequently know how to prevent it or use it constructively in a professionally oriented translation.
Ceremonial portraits of Prince Peter Lvovich Wittgenstein in the context of his iconography
Authors: Popko O. N. 
Published: August 2021

The article is devoted to the study of three ceremonial portraits of Prince Peter Lvovich Wittgenstein, a general of the Russian army and the richest landowner in Belarus in the 19th century. Most of ceremonial portraits of 19th century military men were perished in the whirlwind of wars and revolutions of the 20th century. Finding each such work, even outside our country, is of great interest.The prince’s maternal ancestors were representatives of the most famous aristocratic family in the history of Belarus. His father was the son of a Russian ﬁeld marshal, hero of the war with Napoleon. Prince Peter did not leave children, all of his portraits are now outside Belarus about the descendants of his sister and brother.The paintings were revealed by the author himself, have not been studied before.The earliest portrait dates from the 1850s. and represents the prince in the uniform of a junior oﬃcer of the Horse Guards Regiment. The author’s name is not known, there is a copy of J. N. Bernhardt. The next portrait was painted by an unknown artist around 1864. The latest portrait represents a prince in a general’s uniform, completed by the Austrian artist Z. L’Alleman in 1888 after the death of his hero. Two copies of this portrait are also kept in private collections of his descendants.The article presents descriptions of portraits and their copies, analysis of the history of creation and existence in the context of the prince’s biography and his iconography, through the prism of the Russian and European tradition of writing ceremonial portraits of government oﬃcials.
INOVASI KEBIJAKAN PUBLIK (TINJAUAN KONSEPTUAL DAN EMPIRIS)
Authors: Sururi Ahmad 
Published: August 2021

Tujuan dari penelitian ini adalah menganalisis inovasi kebijakan publik dalam perspektif konseptual dan empiris disertai dengan berbagai contoh penerapan kebijakan publik yang berbasis inovatif dari berbagai daerah. Inovasi kebijakan publik sebagai sebuah keniscayaan secara prinsip dan substantif akan memberikan penguatan dalam merespon dan menyelesaikan problematika kebijakan publik yang berlangsung di tengah masyarakat. Metode yang digunakan adalah pendekatan kualitatif. Teknik yang dilakukan oleh peneliti adalah survei literatur akademis di bidang keilmuan kebijakan publik guna memperoleh konsep-konsep yang relevan dengan kajian inovasi kebijakan publik. Sedangkan pengumpulan data dilakukan melalui penelusuran berbagai sumber baik dari dokumen pemerintah maupun pemberitaan media massa cetak dan elektronik sebagai data sekunder yang kemudian diolah dan dideskripsikan dalam bentuk narasi sesuai dengan kebutuhan data. Kemudian dilakukan analisis data berdasarkan teori dan konsep kebijakan publik serta selanjutnya dilakukan proses intreprtasi data. Hasil yang ingin dicapai dalam penelitian ini adalah adanya upaya-upaya inovasi kebijakan publik yang berdimensi kebaruan dan kemanfaatan sehingga diharapkan dapat memberikan dampak pada upaya yang lebih kongkrit dan membangun partisipasi masyarakat secara berkesinambungan. Inovasi diterapkan bukan hanya pada tahap evaluasi kebijakan publik akan tetapi diterapkan sejak awal perencanaan kebijakan publik, implementasi dan evaluasi kebijakan publik.
Prevalence of Vitamin B12 Deficiency In Patients With Type II Diabetes Mellitus On Metformin
Authors: Malla D. , Bajracharya M.R. , Karki B.B. , Rajouria A.D. , Shrestha P.S. 
Published: August 2021

Background: Diabetes Mellitus is one of the most encountered disease in our out patient department and metformin is the first drug of choice to treat Diabetes mellitus. As metformin is one of the cheapest drug, many patients use these drug for long period of time with consultation and without consultations with doctors. Patients under long term metformin use are not aware of Vitamin B12 deficiency and its associated signs and symptoms. In Nepal due to poverty, lack of education and awareness on diabetes mellitus we doctors find much difficult to explain patients on the consequences of diseases. So I decided to do this study which could be much easier to explain patients on effect of metformin of vitamin B12 levels and the consequences life style modifications and supplement of Vitamin B12 to the patients.
Methods: This is a Cross-Sectional Study done in the patients with Type 2 diabetes were selected based on inclusion and exclusion criteria. Basic biochemical investigation were sent the lab of the National academy of medical science. Serum B12 assay were done. Vitamin B12 deficiency is defined as values <150pg/ml. Association between vitamin B12 deficiency with duration of metformin therapy, duration of diabetes, with age, sex were done.
Results: The mean vitamin B12 level is low as the duration of metformin treatment increases. The sex, age relation with development of vitamin B12 deficiency was not significant. In my study out of 210 patients 107 patients were having severe vitamin B12 deficiency level and 63 patients had a borderline Vitamin B12 deficiency level which shows that the deficiency increases as per longer use of metformin, which shows prevalence of 50.95%.
Conclusions: Vitamin B12 deficiency occurs in type 2 diabetes mellitus patients treated with long term metformin. The duration of metformin therapy significantly affects the development of vitamin B12 deficiency. As a treating physician we always need to explain our patients about the side effect of metformin and regular follow up and investigations must be done to early diagnosis of vitamin B12 deficiency to improve the quality of life.