bluuebunny/crossref_metadata_2025 huggingface dataset:
Benefits and Challenges of ODeL in Postgraduate Education: The Case of Unisa–Ethiopia
Authors: Aberra Tsige GebreMeskel
Published: August 2021

The focus of this paper is on identifying the benefits and the challenges of the open distance e-learning mode of education and their relationship with learners’ satisfaction. A total of 78 master’s and doctoral graduates responded to a 35-item 7-dimensional Likert-scale questionnaire that consisted of 2 open-ended items that allowed respondents to write their reflections. Means, standard deviations, Pearson’s correlation and stepwise regression were used to analyse the quantitative data, whereas the data from the open-ended items were analysed thematically. The results showed that studying in the open distance e-learning system assists learners to develop professional competence, personality skills and computer skills. It has given them access to postgraduate education, accomplishment of problem-solving research, studying from the comfort of home while earning a living, access to rich library resources, and increased life skills such as research language and independent learning. Although the benefits outweighed the challenges, the main challenge that stood out in this paper was the lack of supervision support. Other challenges were loss of motivation, procrastination, poor internet connections, lack of human touch, and lack of support from employers. The paper recommends that open distance e-learning institutions improve their supervision systems and ensure that their student support systems contribute to curbing students’ challenges including feelings of isolation.
School Police Reform: A Public Health Imperative
Authors: Gonzalez Thalia , Kaeser Emma
Published: August 2021

Out of the twin pandemics currently gripping the United States¬—deaths of unarmed Black victims at the hands of police and racialized health inequities resulting from COVID-19—an antiracist health equity agenda has emerged that identifies racism as a public health crisis. Likewise, calls for reform of school policing by those advocating for civil rights, racial justice, and Black Lives Matter have simultaneously intensified. Yet each remains siloed, despite the natural connection and implicit overlap between these separate movements and debates. Indeed, there are documented negative health effects of school policing for Black, Indigenous, people of color (BIPOC) youth. But these have gone largely ignored or underemphasized by the movement to reform school police. Similarly, the racial health equity movement has overlooked race-conscious health equity reforms to school policing. This Article aims to fill the gap by connecting these distinct movements and debates and articulating a public-health-based response to school policing.
The Strength of the Fragrance for One and a Half Thousand Years: Agarwood in the Japanese Art of Incense
Authors: Voytishek Elena E. , Rechkalova Anastasia A.
Published: August 2021

This article gives a brief overview of the genesis of the development of incense culture in Japan through the determining function of aromatic wood in Buddhism, as well as the significance of Japanese classifications of agarwood (aquilaria) species which were developed in the 16th – 17th centuries. Japanese masters invented ways of coding fragrances of aromatic wood through their characteristics of tastes and place of growth, as well as using metaphorical and figurative-symbolic meaning of each name. These techniques played a key role in the history of the traditional art of koudou (‘way of fragrance’) and in the development of female education during the Edo period (1603–1867). Based on the analysis of written sources and museum collections, two classifications were studied, which are still used in Japan when assessing the quality of aromatic wood and wood products: a list of ‘61 kinds of aromatic wood’, developed using associations of odours with significant phenomena in Japanese society as its foundation – calendar holidays, religious concepts, political and literary characters, as well as the system of ‘Six Countries – Five Flavours’, which was based on geographical factors and the principle of reliance on taste and olfactory receptors.
Zenina Lyubov Vasilievna (1936–2018) – The Preceptor and the Keeper of Traditions for Japan and Korean Studies at the Oriental Department in Leningrad University (For Hundred Years Anniversary)
Authors: Philippov Alexander V.
Published: August 2021

This article commemorates the 100th year anniversary since the birth of the prominent Soviet scholar and professor of Japanese and Korean History – L. V. Zenina (1920–2018). The article describes the landmarks of her lifetime activities and academic career. The significance of the traditions and its continuity in Russian oriental studies is depicted by Zenina’s tutorial talents and by means of the human factor.
Western Literature Translations and Their Impact on the Development of the Detective Genre in China in Early 20th Century
Authors: Mitkina Evgenia I.
Published: August 2021

The article is devoted to the study of the impact of Western literature translations on the development of the detective genre in China. Active introduction of China to the Western tradition in the late 19th – early 20th century led to the emergence of a large amount of translated literature. Writers of the first half of the 20th century were innovators, they borrowed in many respects from the form of Western detective stories, which was a rather natural phenomenon considering the necessity to accumulate experience for the creation of a distinct style. A new private detective hero appeared – Huo Sang in Cheng Xiaoqing’s novellas, Li Fei in Lu Tan’an’s stories, Song Wuqi in Zhang Biwu’s stories, as well as the ‘anti-detective’ gentleman thief Lu Ping in Sun Liaohong’s works. Although the names of these writers are not very well known, precisely their works lay the foundation for further development of the detective genre in Chinese literature.
Language Style in Poetry Mahmud Sami Basha al–Barudi (A Stylistic Analysis) | Gaya Bahasa dalam Puisi Mahmud Sami Basha al–Barudi (Suatu Analisis Stilistik)
Authors: Najah Zughrofiyatun , Hijriyah Umi , Mizan Ahmad Nur , Amalia Dian Risky
Published: August 2021

This study aims to examine the language style (al–uslub) used by al- Barudi in his poetry with the theme of life descriptions by describing the main idea or theme, elements of feeling or emotion, and language style based on aspects of diction or choice of words, syntax or sentence structure and rhetorical aspect or meaning. This research is a type of qualitative research with a descriptive-analytical literature study by referring to Al-Barudi's poetry text as the primary source. The data analysis method used is content analysis (tahlil al–madmun).  The author uses a stylistic approach in examining and analyzing the language styles used by the poets in this poem. In examining this poem, the writer will use the stylistic theory proposed by Gorys Keraf related to the classification of types of diction, language style based on syntactic aspects, and rhetorical aspects or meaning. This poetry has the theme of "life description" with a choice of words that still maintain aesthetic values supported by a very strong language style or (al–uslub). The language style contained in the poem is very strong and appropriate with the characteristics of the neoclassical genre of poetry pioneered by al-Barudi at that time, although free, but still strongly adheres to wazan and qafiyah. Seen from the aspect of diction, the words chosen by the poet in sya'ir are quite easy to understand in a popular style. Then from the aspect of sentence structure or syntax, this poem has a climax style. The language styles based on the meaning contained in this poem are hyperbole, simile, pleonasm, apostrophe, ellipsis, assonance, erotesis, and euphemism.
Observational Instruments in the Arab Scientific Heritage Perspective Ismail ibn Heba Allah al-Hamawi | Al Alät Al Rosydiyyah fi At Thurost Al ‘Ilm Al ‘Aroby ‘Indä Ismäil ibn Hebä Allah al-Hämäwi
Authors: Rifai Elkhayati
Published: August 2021

The article is an edited and critical study of an unpublished astronomical text entitled "The Astronomical Instrument Known as The Two-Pronged Machine" of a Damascene astronomer from the thirteenth century AD, Ismail ibn Heba Allah al-Hamawi. ancient scientific texts on this instrument are written by al-Kindi then Ibn Abbad and al-Nayrizi. Al-Kindi's text is the only text published from ancient texts, and today we present to researchers in the development of astronomical instruments a new text to contribute to enriching our knowledge of the scientific tradition of astronomical instruments in Islamic civilization.
An error estimate of a regularizing algorithm based on the generalized residual principle when solving integral equations
Authors: Танана В.П. , Сидикова А.И.
Published: August 2021

Исследован регуляризующий алгоритм приближенного решения интегральных уравнений первого рода, включающий в себя конечномерную аппроксимацию исходной задачи, а также получена оценка погрешности этого алгоритма. Для получения этой оценки доказана эквивалентность обобщенного метода невязки и обобщенного принципа невязки. Этот результат может быть положен в основу оценивания конечномерных аппроксимаций регуляризованных решений.

A regularizing algorithm for the approximate solution of integral equations of the first kind is studied. This algorithm involves a finite-dimensional approximation of the original problem. An error estimate is proposed. In order to obtain this estimate, the equivalence of the generalized residual method and the generalized residual principle is proved. This result can be used to estimate the finite-dimensional approximations of regularized solutions.
A modification of the CABARET scheme for the computation of multicomponent gaseous flows
Authors: Данилин А.В. , Соловьев А.В.
Published: August 2021

Предложен явный численный алгоритм для расчета одномерного движения смеси идеальных газов. Приведены физическая модель и уравнения движения смеси в консервативной и характеристической формах. Дискретизация уравнений движения выполнена по методике Кабаре. Предложенный численный алгоритм испытан на решении задачи о распаде разрыва с различными газами по разные стороны разрыва. Произведено сравнение численных решений с аналитическим, а также с решениями, полученными по другим численным методикам. Показано, что предложенный алгоритм демонстрирует высокую точность решений на рассмотренном классе задач.

An explicit numerical algorithm for computing one-dimensional motion of multicomponent gaseous mixtures is proposed. A physical model and the equations of motion are presented in conservative and characteristic forms. The discretization of the governing equations is made in accordance with the CABARET (Compact Accurately Boundary Adjusting-REsolution Technique) approach. The proposed algorithm is tested on the Riemann problem with different gases on the different sides of the initial discontinuity. The resulting numerical solutions are compared with the analytical one and with those obtained by other numerical approaches. It is shown that the proposed algorithm is of high accuracy on the class of problems being considered.
A parallel algorithm for solving 2D Poisson's equation in the context of nonstationary problems
Authors: Снытников Н.В.
Published: August 2021

Предложен новый параллельный метод решения задачи Дирихле для уравнения Пуассона в контексте нестационарных задач математической физики. Метод основан на декомпозиции прямоугольной декартовой области решения в одном направлении, решении уравнения Пуассона в каждой подобласти прямым методом и сопряжении подобластей с помощью быстрого вычисления потенциала выделенного слоя экранирующих зарядов.
Тестовые эксперименты, проведенные на суперкомпьютерах Межведомственного суперкомпьютерного центра и Сибирского суперкомпьютерного центра, показали хорошую масштабируемость алгоритма.

A new parallel method to solve the Dirichlet problem for Poisson's equation in the context of nonstationary problems of mathematical physics is proposed. This method is based on a decomposition of a rectangular Cartesian domain in one direction, on a direct method of solving Poisson's equation in each subdomain, and on the coupling of the subdomains using a fast procedure for evaluating a single layer potential. A number of test experiments conducted on supercomputers installed at Joint Supercomputing Center of Russian Academy of Sciences and at Siberian Supercomputing Center show a good weak and strong scalability of the parallel algorithm.
A stochastic modification of the spherical block-and-fault model of lithosphere dynamics and seismicity
Authors: Мельникова Л.А. , Розенберг В.Л.
Published: August 2021

Представлено краткое описание последней версии сферической блоковой модели, в которой рассмотрены возможности учета случайных факторов, существенным образом влияющих на динамику модельных параметров. Протестировано два варианта введения стохастической компоненты в процедуры вычисления сил, действующих на блок и фактически определяющих модельные землетрясения: во-первых, зашумление дифференциальных уравнений, описывающих динамику упругих сил и неупругих смещений, и во-вторых, использование случайных величин при задании порогов прочности среды тектонических разломов. Проведенные вычислительные эксперименты продемонстрировали перспективность внедрения стохастики в модель.

A brief description of the last version of the spherical block-and-fault model is discussed. This version takes into account random factors essentially influencing the dynamics of model parameters. Two variants of introducing stochasticity into the procedures for calculating the forces acting on a block and determining the model earthquakes are tested. This stochasticity
consists in (i) adding a noise to the differential equations describing the dynamics of elastic forces and inelastic displacements and in (ii) using random quantities when specifying strength thresholds for the medium of tectonic faults. Numerical experiments demonstrate the perspectivity of introducing stochasticity into the model.
An implementation of vortex methods for modeling 2D incompressible flows using the CUDA technology
Authors: Марчевский И.К. , Кузьмина К.С. , Гречкин-Погребняков С.Р.
Published: August 2021

Исследована возможность ускорения вычислений в методе вихревых элементов - бессеточном лагранжевом методе вычислительной гидродинамики - за счет использования графических ускорителей. Реализован алгоритм, основанный на авторской модификации метода вихревых элементов, позволяющий проводить все необходимые вычисления непосредственно на графическом ускорителе с использованием технологии CUDA. Скорость решения типичной задачи на одном ускорителе GeForce GTX 970 или Tesla C2050 оказывается соизмеримой со скоростью решения аналогичной задачи на кластере, содержащем 30-40 ядер, при использовании технологии MPI. Полученные результаты говорят о высокой эффективности применения графических ускорителей при решении задач гидродинамики вихревыми методами.

The possibility of computation speedup in the vortex element method (a meshfree Lagrangian method of computational fluid dynamics) using the graphics accelerators is studied. An algorithm based on the authors' modification of the vortex element method is implemented; this algorithm allows one to perform all the necessary computations directly on a GPU using the CUDA technology. The speed of solving a typical problem on a single GeForce GTX 970 or Tesla C2050 accelerator is comparable with the speed of solving a similar problem on a cluster containing 30-40 cores with the use of the MPI technology. The numerical results obtained confirm a high efficiency of using graphics accelerators when solving the problems of hydrodynamics with vortex methods.
Optimization of modeling the water-oil mixture filtration in elastic porous media for clusters with Xeon Phi accelerators
Authors: Киреев С.Е.
Published: August 2021

На основе разработанного ранее программного комплекса для моделирования многофазных потоков в деформируемой пористой среде реализован новый параллельный программный комплекс, оптимизированный для запуска на кластере с ускорителями Intel Xeon Phi. Рассмотрены различные способы оптимизации, специфичные для данного ускорителя, и их влияние на время работы программы. Выполнено сравнение различных способов использования ускорителей в составе кластера: симметричного режима и режима offload. Получены оценки ускорения и эффективности при использовании различного числа узлов кластера.

On the basis of a previously developed program for modeling the multiphase flows in finite-deformed porous media, a new parallel program optimized for clusters with Intel Xeon Phi accelerators is implemented. Several optimization techniques
specific for such accelerators are considered and their effect on the program execution time is discussed. A comparison of the symmetric and offload programming models for the accelerators is performed. The parallelization speedup and efficiency are estimatedwhen using various numbers of cluster's nodes.
An efficient implementation of the lattice Boltzmann method for hybrid supercomputers
Authors: Бикулов Д.А.
Published: August 2021

Рассмотрены особенности эффективной реализации метода решеточных уравнений Больцмана (Lattice Boltzmann method, LBM) для гибридных суперкомпьютерных систем с множеством видеокарт. Описаны основные стратегии по сокращению требуемой для работы LBM памяти на графическом ускорителе. Представлены результаты измерения зависимости производительности реализованного программного модуля от числа задействованных видеокарт, полученные на суперкомпьютере Ломоносов.

A number of features of an efficient implementation of the lattice Boltzmann method (LBM) for hybrid supercomputers with many graphics processing units (GPU) are discussed. The main strategies for reducing the memory space required by LBM are described. The performance dependence of the implemented solver on the number of the GPUs in use is analyzed for the Lomonosov supercomputer installed at Moscow State University.
On an approximate analytical method of solving ordinary differential equations
Authors: Арушанян О.Б. , Волченскова Н.И. , Залеткин С.Ф.
Published: August 2021

Описано использование смещенных рядов Чебышёва для интегрирования обыкновенных дифференциальных уравнений. Данный подход основан на аппроксимации решения задачи Коши для нормальной системы обыкновенных дифференциальных уравнений и его производной частичными суммами ряда Фурье по смещенным многочленам Чебышёва первого рода. Коэффициенты рядов вычисляются посредством итерационного процесса с применением квадратурной формулы Маркова. Подчеркнуто, что благодаря своим аппроксимационным свойствам частичные суммы рядов Чебышёва стали основой для построения приближенного аналитического метода интегрирования дифференциальных уравнений. Наряду с общими вопросами рассмотрен ряд примеров по применению частичных сумм ряда Чебышёва для приближенного представления решения задачи Коши на заданном отрезке для обыкновенных дифференциальных уравнений.

The application of shifted Chebyshev series for solving ordinary differential equations is described. This approach is based on the approximation of the solution to the Cauchy problem for a normal system of ordinary differential equations and its derivatives by partial sums of Fourier series in the Chebyshev polynomials of the first kind. The coefficients of the series are determined by an iterative process with the use of Markov's quadrature formulas. The approximation properties of shifted Chebyshev series allow us to propose an approximate analytical method for ordinary differential equations. A number of
examples are considered to illustrate the application of partial sums of Chebyshev series for approximate representations of the solutions to the Cauchy problems for ordinary differential equations.
A modification of the CABARET scheme for numerical simulation of multicomponent gaseous flows in two-dimensional domains
Authors: Данилин А.В. , Соловьев А.В. , Зайцев А.М.
Published: August 2021

Предложен явный численный алгоритм для расчета течений смесей идеальных газов в двумерных областях. Приведены физическая модель и уравнения движения смеси в консервативной и характеристической формах.
Дискретизация уравнений движения произведена по методике Кабаре. Алгоритм испытан на задачах о прохождении ударной волны в воздухе через неоднородности из легкого и тяжелого газов, начальные условия для которых адаптированы из рассмотренных другими авторами натурных и численных экспериментов. Показано хорошее совпадение расчетов по предложенному алгоритму с результатами этих экспериментов.

An explicit numerical algorithm for calculation of two-dimensional motion of multicomponent gas mixtures is proposed. A physical model as well as conservative and characteristic forms of governing equations are given. The discretization of the governing equations is made in accordance with the CABARET (Compact Accurately Boundary Adjusting-REsolution Technique) approach. The proposed algorithm is tested on problems of air shock waves passing through dense and dilute volume inhomogeneities with initial conditions adopted from numerical and experimental studies of other authors. A good agreement between the results of these studies and those obtained by the CABARET approach is shown.
A variable structure algorithm using the (3,2)-scheme and the Fehlberg method
Authors: Новиков Е.А.
Published: August 2021

Построен (3,2)-метод третьего порядка с замораживанием матрицы Якоби, в котором $L$-устойчивыми являются основная и промежуточные численные схемы. Получено неравенство для контроля точности вычислений с использованием вложенного метода второго порядка. Предложено неравенство для контроля устойчивости явного
трехстадийного метода Рунге-Кутта-Фельберга третьего порядка. Сформулирован алгоритм переменной структуры, в котором на каждом шаге явный или $L$-устойчивый метод выбираются по критерию устойчивости. Приведены результаты расчетов.

A third-order (3,2)-method allowing freezing the Jacobi matrix is constructed. Its main and intermediate numerical schemes are $L$-stable. An accuracy control inequality is obtained using an embedded method of second order. A stability control inequality for the explicit three-stage Runge-Kutta-Fehlberg method of third order is proposed. A variable structure algorithm is formulated. An explicit or $L$-stable method is chosen according to the stability criterion at each step. Numerical results are discussed.
An iterative method for determining the shape and conductivity of a homogeneous inclusion in the two-dimensional electrical impedance tomography problem
Authors: Гаврилов С.В.
Published: August 2021

Рассматривается двумерная задача электроимпедансной томографии в случае ограниченной области с кусочно-постоянным коэффициентом электрической проводимости, принимающим два значения. Требуется определить неизвестную кривую, разделяющую области с различной проводимостью, и восстановить значение проводимости внутри одной из этих областей по измерениям характеристик электрического поля на известной внешней границе области. Предлагается итерационный метод численного решения поставленной задачи, приводятся результаты вычислительных экспериментов.

The problem of electrical impedance tomography in a bounded two-dimensional domain with a piecewise two-valued constant electrical conductivity is considered. It is required to determine an unknown boundary between the regions of different conductivities and to obtain the conductivity in one of these regions using the input information on the electric field measured on the outer boundary of the domain. An iterative method for solving this problem is proposed. The corresponding numerical results are discussed.
Aspects of parallel computing to solve Helmholtz equation by a direct solver with low-rank approximation and the HSS format of data storage
Authors: Глинский Б.М. , Костин В.И. , Кучин Н.В. , Соловьев С.А. , Чеверда В.А.
Published: August 2021

Предложен алгоритм решения систем линейных алгебраических уравнений (СЛАУ), основанный на методе исключении Гаусса и предназначенный для решения уравнения Гельмгольца в трехмерных неоднородных средах. Для решения СЛАУ, возникающих в геофизических приложениях, разработана параллельная версия алгоритма,
направленная на использование гетерогенных высокопроизводительных вычислительных систем, содержащих узлы с MPP- и SMP-архитектурой. Малоранговая аппроксимация, HSS-формат и динамическое распределение промежуточных результатов среди кластерных узлов позволяют решать задачи в разы большие, чем при использовании традиционных прямых методов, сохраняющих блоки $L$-фактора в полном ранге (Full-Rank, FR).
Использование предложенного алгоритма позволяет сократить время расчетов, что актуально для решения трехмерных задач геофизики. Численные эксперименты подтверждают упомянутые преимущества предложенного малорангового прямого метода (Low-Rank, LR) по сравнению с прямыми FR-методами. На модельных
геофизических задачах показана жизнеспособность реализованного алгоритма.

An algorithm for solving systems of linear algebraic equations based on the Gaussian elimination method is proposed. The algorithm is aimed to solve boundary value problems for the Helmholtz equation in 3D heterogeneous media. In order to solve linear systems raised from geophysical applications, we developed a parallel version targeted on heterogeneous high-performance computing clusters (MPP and SMP architecture). Using the low-rank approximation technique and the HSS format allows us to solve problems larger than by the use of traditional direct solvers with saving the L-factor in full rank (FR). Using the proposed approach reduces computation time; it is the key-point of 3D geophysical problems. Numerical experiments demonstrate a number of advantages of the proposed low-rank approach in comparison with direct solvers (FR-approaches).
Intermittency of vector fields and natural random number generators
Authors: Калинин А.О. , Соколов Д.Д.
Published: August 2021

Рассматривается процесс роста поля Якоби на геодезической на двумерном многообразии с псевдослучайной величиной гауссовой кривизны. Исследуются различные естественные генераторы псевдослучайных чисел, основанные, в первую очередь, на гипотезе о случайном распределении десятичных знаков иррациональных чисел.

Growth of Jacobi fields on geodesic lines over a 2D manifold with Gaussian curvature as a random process is considered. We study various natural random number generators on the basis of the hypothesis that the decimals of irrational numbers are randomly distributed.
Increasing the interval of convergence for a generalized Newton's method of solving nonlinear equations
Authors: Громов А.Н.
Published: August 2021

Рассмотрен подход к построению расширения промежутка сходимости ранее предложенного обобщения метода Ньютона для решения нелинейных уравнений одного переменного. Подход основан на использовании свойства ограниченности непрерывной функции, определенной на отрезке. Доказано, что для поиска действительных корней вещественнозначного многочлена с комплексными корнями предложенный подход дает итерации с нелокальной сходимостью. Результат обобщен на случай трансцендентных уравнений.

An approach to the construction of an extended interval of convergence for a previously proposed generalization of Newton's method to solve nonlinear equations of one variable. This approach is based on the boundedness of a continuous function defined on a segment. It is proved that, for the search for the real roots of a real-valued polynomial with complex roots, the proposed approach provides iterations with nonlocal convergence. This result is generalized to the case transcendental equations.
An approximation algorithm for the treatment of sound points in the CABARET scheme
Authors: Головизнин В.М. , Соловьев А.В. , Исаков В.А.
Published: August 2021

Описана новая вычислительная технология расчета потоковых переменных на новом временном слое в разностных схемах типа Кабаре для численного решения квазилинейных гиперболических уравнений в частных производных. Новая технология позволяет единообразно рассматривать все случаи возникновения звуковых точек и не нарушает свойства временной обратимости разностных схем при отсутствии нелинейной коррекции потоков.

A new numerical approach to the calculation of flux variables on a new time layer in the CABARET (Compact Accurately Boundary Adjusting-REsolution Technique) scheme for the numerical solution of quasilinear hyperbolic differential equations is described. This approach allows one to uniformly treat all cases of sound points and does not violate the time reversibility properties of difference schemes in the absence of nonlinear correction of fluxes.
A method of numerical simulation of flow separation at the inlet of a circular thin-walled pipe
Authors: Логачев К.И. , Аверкова О.А. , Логачев А.К. , Толмачева Е.И. , Горлов А.С.
Published: August 2021

Разработан метод математического моделирования, вычислительный алгоритм и программа для расчета отрывного течения на входе в круглый всасывающий патрубок с тонкими стенками при наличии как высокоскоростного, так и низкоскоростного набегающего потока. Для построения дискретной модели используются стационарные дискретные вихревые кольца. Адекватность разработанного метода подтверждается удовлетворительным качественным и
количественным согласованием с результатами расчетов других авторов.

A mathematical simulation method, a computational algorithm and a software program are developed to calculate a separated flow at the inlet of a circular thin-walled pipe in the case of a high-speed or low-speed incident flow. In order to construct a discrete model, the stationary discrete vortex rings are used. The adequacy of the proposed method is confirmed by the satisfactory qualitative and quantitative agreement with the numerical results obtained by other authors.
A study of coupling between viscoelastic parameters using the singular value decomposition analysis
Authors: Ефимова Е.С.
Published: August 2021

Исследуется решение обратной задачи сейсмики в линеаризованной постановке для модели вязкоупругой среды. Для описания сред с поглощением используется обобщенная модель стандартного линейного твердого тела, опирающаяся на $\tau$-метод. Если при численном решении неоднородность одного из искомых параметров
переходит в изменчивость другого, то такие параметры называются связанными. Связанность параметров является одним из проявлений некорректности изучаемой задачи. Для ее преодоления необходимо привлечение регуляризующей процедуры. В качестве таковой в работе предлагается использовать усечение сингулярного
разложения для одновременного определения скорости продольных волн и их поглощения. В качестве параметризации среды рассматривается комбинация параметров Ламе и добротности.

The solution of a linearized inverse seismic problem of viscoelasticity is studied. The generalized standard linear solid model and the $\tau$ method are used to describe media with attenuation. If the heterogeneity of one of the sought parameters influence the variability of another one during the process of numerical solution, then such parameters are said to be coupled. Such a coupling is a sign of ill-posedness of the original problem. A regularization is necessary to overcome this difficulty. To accomplish this, we propose the truncation of the singular value decomposition to simultaneously determine the P-velocity and its attenuation. A combination of the Lame parameters and the quality factor are used as the parametrization of the medium under consideration.
On the correctness of numerical simulation of gravitational instability with the evolution of multiple gravitational collapses
Authors: Снытников В.Н. , Стояновская О.П.
Published: August 2021

Изучена корректность численных моделей на основе SPH-метода для нестационарных задач гравитационной газодинамики с развитием гравитационных неустойчивостей, в том числе с формированием множественных коллапсов газа в околозвездном диске. Исходные дифференциальные начально-краевые задачи некорректны из-за своей неустойчивости к изменению входных данных. Показано, что в численном методе на основе SPH для решения этих некорректных задач проводится следующая регуляризация: 1) если решение исходной неустойчивой задачи существует на всей временной оси, то ограниченность области изменения переменных в численном методе позволяет удовлетворить условию его устойчивости к малым изменениям входных данных; 2) если решения исходной неустойчивой задачи существуют только на ограниченном временном интервале, как в случае множественных коллапсов, то устойчивый численный метод строится на классе функций, ограниченных фиксированной постоянной, выбираемой из физических соображений. На этом классе функций исходная задача тоже становится корректной. Комбинация SPH-метода с сеточным методом расчета гравитационных сил позволяет обеспечить такую ограниченноcть численных решений. Для выяснении смысла приближенных численных решений, получаемых в вычислительных экспериментах, следует использовать интегральные функции, слабо чувствительные к деталям численного алгоритма.

We study the correctness of numerical models based on the SPH-method for nonstationary problems of gravitational gas dynamics with the development of gravitational instability, including with the formation of multiple collapses of a gas in a circumstellar disk. The original differential initial boundary value problems are ill-posed because of their instability with respect to variations of input data. It is shown that the following regularization is performed in the SPH-based numerical method of solving such problems: (1) if the solution to the original unstable problem exists on the entire time axis, then the condition of the method's stability with respect to small variations of input data is satisfied due to a bounded range of the variables; (2) if the solution of the original unstable problem exists only on a bounded time interval, as in the case of multiple collapses, then a stable numerical method can be developed on a class of functions bounded by a fixed constant chosen from physical considerations. On this class of bounded functions, the original problem becomes well-posed. A combination of the SPH method with a grid-based method of calculating the gravitational forces allows one to ensure the boundedness of numerical solutions. In order to clarify a meaning of the approximate numerical solutions obtained by computer simulations, it is necessary to use the integral functions weakly sensitive to the details of the numerical algorithm in use.
Implicit and time reversible CABARET schemes for quasilinear shallow water equations
Authors: Головизнин В.М. , Горбачев Д.Ю. , Колокольников А.М. , Майоров П.А. , Майоров П.А. , Тлепсук Б.А.
Published: August 2021

Предложена новая неявная безусловно устойчивая схема для одномерных уравнений мелкой воды, сохраняющая все особенности явной схемы Кабаре. Проведен анализ диссипативных и дисперсионных свойств новой схемы и предложен алгоритм ее численного решения. Приведены примеры решения задачи о распаде разрыва.

A new implicit unconditionally stable scheme for the one-dimensional shallow water equations is proposed. This implicit scheme retains all the features of the explicit CABARET (Compact Accurately Boundary Adjusting-REsolution Technique) difference scheme. Dissipative and dispersion properties of this new scheme are analyzed; an algorithm of its numerical solution is discussed. Some examples of solving the Riemann problem are considered.
On a problem of the synthesis of binary nano-optical elements
Authors: Гончарский А.А. , Серёжников С.Ю.
Published: August 2021

В рамках широко распространенной технологии Augmented Reality обсуждается возможность контроля подлинности защитных оптических меток на основе бинарных нанооптических элементов. С помощью смартфона фотографируют изображение защитной метки. Полученное изображение интерпретируется как дифракционный оптический элемент. В приближении Френеля рассчитывают изображение, формируемое дифракционным оптическим элементом, которое используют для идентификации подлинности защитной метки. Защитная метка представляет собой фазовый оптический элемент, глубина микрорельефа которого не превышает 0.5 мкм. Нанооптические элементы изготавливаются с помощью электроннолучевой литографии. Разработанные нанооптические элементы устойчивы к частичному повреждению микрорельефа и могут быть использованы для идентификации банкнот, документов и др.

This paper deals with optical security label identification technology as a part of augmented reality technology. Security labels are based on binary nanooptical elements and are photographed using a smartphone. Photographed images are interpreted as diffractive optical elements. Optical images formed by these diffractive elements are computed using the Fresnel approximation. These images are used to identify the security labels. A security label consists of a phase optical element whose microrelief height is of no more than 0.5 $\mu$m. Nanooptical elements are manufactured using electron-beam lithography. The optical security labels are resistant against microrelief damages and can withstand partial loss of an image. The optical elements developed can be used to protect and identify banknotes, documents, etc.
What a patient needs to know about the virus human papillomas and cervical cancer?
Authors: Sinchikhin Sergei P. , Stepanyan Lusine V.
Published: August 2021

According to experts of the World Health Organization, cervical cancer is the only cancer that can be completely prevented through the introduction of mass screening and educational information in the population. One of the activities of the obstetrician-gynecologist is the conduct of health education. However, for a variety of reasons, a practical doctor may have difficulty preparing for informational and educational meetings with patients.

Aim. To prepare a clinical lecture for the obstetrician-gynecologist, which can be used in educational work with the population on the prevention of human papillomavirus infection and cervical cancer.

Materials and methods. The information material includes data from foreign and domestic scientific articles available at PubMed on this topic and published over the past 10 years.

Results. A systematic analysis of the data contained in the modern literature on human papillomavirus, human papillomavirus infection and cervical cancer has been carried out. Information is presented on the prevalence of diseases, diagnostic methods, and features of the course of human papillomavirus infection, the role of human papillomavirus in the development of cervical cancer. Attention is drawn to the importance of preventive examinations. Part of the information is presented in the form of answers to patients questions, which makes the information presented especially memorable.

Conclusion. It is hoped that the prepared lecture will be useful for the educational work of the obstetrician-gynecologist and will increase the educational information of the population on the prevention of cervical cancer.
Endometrial hyperplasia: without atypia and with atypia
Authors: Sabantsev Maksim A. , Shramko Svetlana V. , Levchenko Vladimir G. , Volkov Oleg A. , Tretyakova Tatyana V.
Published: August 2021

The article analyzes and presents data for the last 70 years from the PubMed database on endometrial hyperplasia (EH), which is one of the leaders in the structure of gynecological diseases and the main predictor of endometrial cancer (EC). The chronicle of the EH classification is highlighted with a focus on changing the designation and relevance of adenomatous EH. It is shown how the current classification of EH, due to the fact that a large number of synonyms is limited by two options, allows to maximize the reproducibility of the diagnosis, improve the interaction of the obstetrician-gynecologist with the pathologist and reduce the treatment inefficiency. The results of modern studies on the prevalence and risk factors of EH and EC differ from previously accepted ones and destroy the Bohman triad. The risks of EH development with tamoxifen and menopausal hormone therapy are determined. The data of current research methods aimed at the diagnosis of EH and EC are indicated. The differences in etiopathogenesis, prevalence, diagnosis, risk factors for development and progression to the malignant process presented in the review represent two types of EH (without atypia and with atypia) as completely different endometrial diseases included in the same classification.
IMPLEMENTING ESG CONCEPT IN SHARIA STOCK SCREENING PROCESS
Authors: Mustafida Rifka , Fauziah Najim Nur
Published: August 2021

Islam places great importance on moral, environmental and social dimension. Sustainable development is centric to the overlapping factors both Islamic finance and Socially Responsible Investment, which are the economy, the environment and social impact. In contrary, Empirical evidence concerning ESG practice of IFIs and Sharia compliant companies is still lacking. The investment portfolio should therefore be scrutinized on the criteria of justice, social welfare and sustainability. This paper aims to identify sustainability report of Sharia Stocks companies and propose i-ESG index for sharia stocks screening in Indonesia. A qualitative study is used to describe sustainability action doing by Sharia compliant companies listed on Indeks Saham Syariah Indonesia (ISSI) in October 2019. This study found that, almost all the companies shows their Good Corporate Governance, but only a few of company have their sustainability report. Therefore a novel parameter to screen the sharia stocks screening process is urgently needed.
The Effect of Internal Control Entities to Determining the High of Audit fee
Authors: Winra Nuryadi , Pontoh Grace Theresia , Pontoh Grace Theresia
Published: August 2021

This research aimed to find out direct effect of the internal control entities to determining the high of audit fee, and indirect effect of the internal control entities to determining the high of audit fee through the extensive of auditor’s occupation. Data collection in this research used questionnaire which distributed to auditors who working in public accounting in Makassar. Analysis of the data used path analysis. The results of this research provided evidance that the internal control entities (X) had a significant direct effect to determining the high of audit fee (Y), and the internal control intities (X) had a significant indirect effect through the extensive of auditors’ occupation (M) to determining the high of audit fee (Y). The implication is if internal control entities is ineffective, it will be effect the larger of the extensive of auditor’s, so it will be also effect to the highest of amount in determining audit fee.
Un Relato Kimbandista, Umbandista y Batuqueiro desde Argentina
Authors: Di Baja Maria Azul
Published: August 2021

El textro propone un breve relato contado en primera persona por parte de la Mae Pequeña de la casa de Santo "Ilé Nueva Conciencia" en Argentina,  quién cuenta  su tránsito en el culto Afrobrasilero, el vínculo con los orixás, las entidades, sus hermanos y  su Mae y cómo éstos la fueron acompañando en su crecimiento tanto en el plano terrenal y espiritual ocupándo un lugar fundamental en su proceso de maduréz.
Ritualidades do Mistério Pessoal: o segredo de orixá no Batuque afro-sul
Authors: De Souza Nunes Marcus Vinicius
Published: August 2021

Nesta pesquisa apresentamos algumas características teológicas e rituais próprias do Batuque, uma religião afro-brasileira típica do sul do Brasil, motivo pelo qual também é referido como Batuque afro-sul. Colocamos esta tradição em perspectiva, olhando-a no contraste com outras tradições religiosas afro-brasileiras, bem como introduzimos a sua característica teológica mais própria, chamada segredo de Orixá, dando seu conceito, sua finalidade ritual e as possíveis origens desta tradição peculiar ao Batuque.
Das Águas Ìyá Oxum: saberes ancestrais femininos em poesias negras diaspóricas
Authors: Sales Cristian
Published: August 2021

Neste artigo, investimos numa discussão acerca dos saberes ancestrais femininos articulados em poesias negras diaspóricas. Dessa maneira, ao apresentar um estudo crítico dos poemas de Lívia Natália e Paula Melissa (Mel Adún), observamos como os arquétipos de Ìyá Oxum são incorporados como tessituras e fundamentos epistêmicos. A partir de contribuições teóricas formuladas na filosofia africana, o texto explora como o orixá feminino Oxum se torna uma “categoria sócio-espiritual” (OyÄ›wùmí, 2016) de abertura para uma transformação epistemológica para ver, sentir e compreender o mundo, em contraposição ao pensamento ocidental.
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Iyás e Abebés: existências, resistências e lutas matriarcais afrodiaspóricas
Authors: Dos Santos Mauricio , Fernando da Silva Anaxsuell
Published: August 2021

Com a Diáspora Negra, aportaram no Brasil as Iyás ”“ mães e Iyabás, que são as divindades matrigestoras afro-brasileiras, vindas do outro lado do Oceano Atlântico. Assim, neste artigo se propõe discutir algumas ideias a respeito de como a divindade afro-brasileira Oxum e o seu espelho de mão, o abebé, são efetivamente belicosos; buscamos também evidenciar alguns elementos das vidas de Makota Valdina, Maria Neném, Doné Runhó, Tia Ciata, Mãe Aninha, Chica Xavier, Mãe Stella de Oxóssi, Mãe Menininha, Olga do Alaketu, Mãe Beata de Iemanjá, Mãe Gilda de Ogun e Giselle Omindarewá, aqui nomeadas como Iyás: Mães de Santo, Matrigeradoras e Matrigestoras afro-brasileiras. A partir de uma pesquisa bibliográfica, identificamos que as lutas antirracistas e feministas são comuns nas vidas dessas Iyás, pois verificamos que em diferentes períodos e em diferentes terreiros essas lutas se repetiram de distintas formas, e compreendemos que as lutas contra o racismo e machismo são constitutivas e/ou uma característica das Iyás afro-brasileiras. Concebemos Oxum como insígnia das Iyás e Iyábás e, entretanto, consideramos que ainda as mulheres de terreiro permanecem invisibilizadas.
Proposta de ensino de eletromagnetismo baseada nos efeitos da corrente elétrica, por meio do uso de vídeos, de experimentos e de uma visita Ã escola da ciência física da cidade de Vitória - ES
Authors: Buffon Luiz Otávio
Published: August 2021

Neste artigo, foi desenvolvida uma proposta didática para o ensino de eletromagnetismo baseada nos efeitos da corrente elétrica. A proposta foi aplicada numa turma de terceiro ano do ensino médio. Os encontros da aplicação ocorreram, em sua maioria, na sala de aula. Contudo, houve uma visita a um espaço não formal de ensino, que foi a Escola da Ciência Física de Vitória ES, sendo esse espaço uma espécie de museu da Física. Esta proposta foi estruturada no procedimento metodológico dos Três Momentos Pedagógicos, que é divido em problematização inicial, organização do conhecimento e aplicação do conhecimento. Nesse sentido, além da utilização de um espaço não formal, tivemos a utilização de vídeos, a fim de motivar os alunos acerca dos assuntos abordados, e encontros com características sociointerativas e dialógicas. De maneira geral, os resultados obtidos neste trabalho foram significativos, e através da análise dos questionários foi possível verificar que houve, para a maioria dos alunos, desenvolvimento conceitual em grande parte do conteúdo.
Verificação da segunda lei de Newton usando molas
Authors: Neves Ubaldo Martins
Published: August 2021

Nesse artigo, propõe-se um experimento didático e de baixo custo, visando a verificação prática da segunda lei de Newton. Para isso, foram medidas as constantes elásticas de duas molas utilizando dois métodos distintos: estático e dinâmico. A concordância entre os resultados assegura a verificação desta importante lei da Física.