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The paper considers mathematical modeling of layered Benard-Marangoni convection of a viscous incompressible fluid. The fluid moves in an infinitely extended layer. The Oberbeck-Boussinesq system describing layered Benard-Marangoni convection is overdetermined, since the vertical velocity is zero identically. We have a system of five equations to calculate two components of the velocity vector, temperature and pressure (three equations of impulse conservation, the incompressibility equation and the heat equation). A class of exact solutions is proposed for the solvability of the Oberbeck-Boussinesq system. The structure of the proposed solution is such that the incompressibility equation is satisfied identically. Thus, it is possible to eliminate the «extra» equation. The emphasis is on the study of heat exchange on the free layer boundary, which is considered rigid. In the description of thermocapillary convective motion, heat exchange is set according to the Newtons law of cooling. The application of this heat distribution law leads to the third-kind initial-boundary value problem. It is shown that within the presented class of exact solutions to the Oberbeck-Boussinesq equations the overdetermined initial-boundary value problem is reduced to the Sturm-Liouville problem. Consequently, the hydrodynamic fields are expressed using trigonometric functions (the Fourier basis). A transcendental equation is obtained to determine the eigenvalues of the problem. This equation is solved numerically. The numerical analysis of the solutions of the system of evolutionary and gradient equations describing fluid flow is executed. Hydrodynamic fields are analyzed by a computational experiment. The existence of counterflows in the fluid layer is shown in the study of the boundary value problem. The existence of counterflows is equivalent to the presence of stagnation points in the fluid, and this testifies to the existence of a local extremum of the kinetic energy of the fluid. It has been established that each velocity component cannot have more than one zero value. Thus, the fluid flow is separated into two zones. The tangential stresses have different signs in these zones. Moreover, there is a fluid layer thickness at which the tangential stresses at the liquid layer equal to zero on the lower boundary. This physical effect is possible only for Newtonian fluids. The temperature and pressure fields have the same properties as velocities. All the nonstationary solutions approach the steady state in this case.

This paper investigates the mechanisms of proton-relaxation polarization and thermally stimulated currents of depolarization (TCDP) in hydrogen bonded crystals (HBC) using methods of quasi-classical kinetic theory. Established generalized expressions for the complex dielectric permittivity (CDP) and polarization incorporates the main frequency of varying polarization field in the infinite approximation of perturbation theory with respect to a small parameter. It is revealed that that the effects of interaction among the relaxation modes of volume charge density starting from the main frequency of the field have already caused abnormally high polarizing nonlinearities in the range of strong fields (10-1000 MV/m) and ultra-high temperatures (550-1500 K). Generalized along the field expressions are established for kinetic equation coefficients. These expressions allow revealing reveal the influence of the field parameters (amplitude and frequency of the EMF) on the microscopic acts of transfer of physical relaxation oscillators (protons) through the potential barrier. The expression for the density of thermally stimulated currents of depolarization in HBC carried out in the wide range of fields (100-1000 MV/m) and temperatures (1-1500 K) is formulated on the basis of the general kinetic equation solution (for the model of a double symmetric potential well with a parabolic barrier). A numerical computation scheme for characteristic parameters oscillators is developed using the minimization comparison function method (MCF-method)., Методами квазиклассической кинетической теории исследуется механизм протонно-релаксационной поляризации и термостимулированной деполяризации в кристаллах с водородными связями (КВС). Построены обобщенные выражения для комплексной диэлектрической проницаемости (КДП) и поляризации, выполняющиеся на основной частоте переменного поляризующего поля в бесконечном приближении теории возмущений по малому параметру. Установлено, что эффекты взаимодействия релаксационных мод объемной плотности заряда уже на основной частоте поля обусловливают аномально высокие поляризационные нелинейности, проявляющиеся в области сильных полей (10-1000 МВ/м) и сверхвысоких температур (550-1500 К). Построены обобщенные нелинейные по полю выражения для коэффициентов кинетического уравнения, позволяющие выявить влияние параметров поля (амплитуда и частота ЭДС) на микроскопические акты перебросов физических релаксаторов (протонов) через потенциальный барьер. Из решения общего квазиклассического кинетического уравнения (для модели двойной симметричной потенциальной ямы с барьером параболической формы) построено выражение для плотности тока термостимулированной деполяризации в КВС, выполняющееся в широком диапазоне полей (100-1000 МВ/м) и температур (1-1500 К). Предложена схема численного расчета характеристических параметров релаксаторов методом минимизации функции сравнения (МФС-методом).

Цель. Основная цель статьи – проанализировать наличие в воде Украины и мира пластика, а также на основании мирового и собственного опыта предложить методы очистки вод от пластика. Методика. Исследования выполнены на основании анализа научных зарубежных и отечественных литературных источников о наличии пластика в воде Украины, европейских стран, США (1999–2018 гг.). Результаты. Изученные источники свидетельствуют, что одной из основных экологических угроз мирового масштаба является наличие пластика в питьевой и сточных водах. Очистные сооружения мира недостаточно приспособлены для обнаружения и улавливания пластика. Авторы представляют результаты комплексного рассмотрения вопросов, связанных с определением наличия пластика в различных водах, его размерами и концентрациями, материалами для его изготовления. Были проведены исследования по определению содержания пластика в питьевой водопроводной воде городов Днипра и Запорожья. Например, в питьевой воде из-под крана содержится от 4 до 10 частиц пластика на литр воды, размер которых превышал 100 микрон, то есть среднюю толщину человеческого волоса. А в бутилированной воде известных торговых марок «Моршинская» и «Buvette» содержится от 49 до 102 частиц пластика на литр воды. Научная новизна. В работе обобщены имеющиеся и представлены новые методы и технологии очистки воды от пластика, такие как: процеживание на различных сооружениях (механические методы), флотационные, мембранные и обратноосмотические системы, мембранные биореакторы (физико-химические и комбинированные методы). Как второй путь снижения количества пластика в воде предложено запрещение его изготовления или создание биоразлагаемого пластика. Практическая значимость. Учитывая распространенность потребления бутилированной воды по всему миру, результаты этого исследования подтверждают необходимость дальнейших исследований воздействия микро- и нанопластов на здоровье человека., Purpose. The main purpose of the article is to analyze the presence of plastic in the water of Ukraine and the world, as well as to suggest the methods for purifying water from plastic on the basis of the world and personal experience. Methodology. The studies were carried out on the basis of the analysis of scholarly domestic and foreign literature sources on the presence of plastic in the water of Ukraine, European countries, and the USA (1999–2018). Findings. The analyzed sources indicate that one of the main environmental threats of global scale is the presence of plastic in drinking and waste waters. The wastewater treatment facilities of the world are not sufficiently adapted to detect and trap plastic. The authors present the results of a comprehensive consideration of the issues related to the determination of the presence of plastic in various waters, their size and concentrations, and manufacturing materials. Plastic, entering the body of people, especially children, animals, sea fish, etc., has a negative influence on their health. Studies have been conducted to determine the content of plastic in drinking tap water in the cities of Dnipro and Zaporozhye. For example, drinking water from the tap contains from 4 to 10 particles of plastic per liter of water, the size of which exceeded 100 microns, that is, the average thickness of a human hair. And in bottled water of well-known trademarks «Morshinska» and «Buvette» contains from 49 to 102 particles of plastic per liter of water. Originality. The paper summarizes the existing and presents new methods and technologies for cleaning water from plastic, such as: filtering on various facilities (mechanical methods), flotation, membranous and reverse-osmotic systems, membrane bioreactors (physical-chemical and combined methods). As a second way to reduce the amount of plastic in water, it is proposed to create biodegradable plastics or prohibit their manufacture. Practical value. Given the prevalence of bottled water consumption worldwide, the results of this study confirm the need for further research on the effects of micro and nanoplastics on human health., Мета. Основна мета статті – проаналізувати наявність у воді України та світу пластику, а також на основі світового і власного досвіду запропонувати методи очищення вод від пластику. Методика. Дослідження виконані на підставі аналізу наукових зарубіжних і вітчизняних літературних джерел про наявність пластику у воді України, європейських країн, США (1999–2018 рр.). Результати. Вивчені джерела свідчать, що однією з основних екологічних загроз світового масштабу є наявність пластику в питній і стічних водах. Очисні споруди світу недостатньо пристосовані для виявлення й уловлювання пластику. Автори представляють результати комплексного розгляду питань, пов’язаних із визначенням наявності пластику в різних водах, його розмірами й концентраціями, матеріалами для його виготовлення. Були проведені дослідження з визначення вмісту пластика в питній водопровідній воді міст Дніпра і Запоріжжя. Наприклад, у питній воді з-під крана міститься від 4 до 10 часток пластику на літр води, розмір яких перевищував 100 мікрон, тобто середню товщину людської волосини. А в бутильованій воді відомих торгових марок «Моршинська» та «Buvette» міститься від 49 до 102 часток пластика на літр води. Наукова новизна. У роботі узагальнені наявні й представлені нові методи й технології очищення води від пластику, такі як: проціджування на різних спорудах (механічні методи), флотаційні, мембранні й зворотноосмотичні системи, мембранні біореактори (фізико-хімічні й комбіновані методи). Як другий шлях зниження кількості пластику у воді запропоновано заборону його виготовлення або створення біорозкладаного пластику, здатного біологічно руйнуватися. Практична значимість. З огляду на поширеність споживання бутильованої води по всьому світу, результати дослідження підтверджують необхідність подальших досліджень впливу мікро- і нанопластів на здоров’я людини.

Diffraction of waves of different physical nature is one of the most important and studied phenomena of nature in connection with its versatile use in devices and measuring techniques. The influence of media motion on the diffraction pattern attracted the attention of researchers in connection with the development of the theory of the electrodynamics of moving media and continues to attract attention in connection with a number of unsolved problems of physics. In this paper, we consider a model of the diffraction of waves on the slit and lattice, located on amovable substrate (medium). Analytical relations for the calculation of the diffraction pattern intensity distribution are obtained. The significant influence of the medium motion on thediffraction pattern is established. The position of the zero-order maximum does not depend on the motion of the medium, on the one hand, the distance between the diffraction maxima decreases, on the other hand, increases, until they disappear. The conditions under which the motion of themedium leads to an asymmetrical appearance of the diffraction intensity distribution, which is not observed in a stationary medium, are established. Generalized conditions of diffraction minima are obtained taking into account the motion of the medium. Shows the effect of the direction of thevelocity of motion of the medium on the intensity of the diffraction pattern.

The search for new types of bone substitutes is one of the topical problems of biology and medicine. The paper considered the role of fibrous autograft in reparative bone regeneration in the rat's lower jaw model. Thirty Wistar rats were taken in the experiment: 15 in the experimental and 15 in the control group. Fibrous autograft was formed on the cellophane basis under the skin on the back of rats. Injury in the lower jaw with a diameter of 2 mm was formed and a fibrous graft was placed in injuries in the experimental group. Five animals from each groups were sacrificed at the first, third and fifth weeks of the experiment. The object of the further research was the samples of the lower jaws stained according to Van Gieson. Histological examination of the bone defect of the experimental group after 1 week showed absence of bone fragments and formation of fibrous callosity in the trauma zone. Further study of regenerate at the 3rd and the 5th weeks showed accelerated bone wound healing in the experimental group (compared to the control group). Thus, the autograft stimulates the process of bone tissue restoration in the area of the defect of the lower jaw model. © 2021 Acta Biomedica Scientifica. All rights reserved.

High technical and economic efficiency of the use of bimetals in chemical, oil, transport and energy engineering and other industries is described. The urgency of creating high-performance continuous processes for the production of bimetallic strips is substantiated. The authors have established the main technological tasks for development of the processes of obtaining bimetal of wide class. The paper describes resource-saving production technology of three-layer bimetals alloyed steel – constructional steel – alloyed steel at the unit of combined process of continuous casting and deformation. Possibilities of the proposed technology are outlined from the standpoint of improving the quality of bimetallic strips. The initial data are given to determine the temperature change over time of the main steel strip as it passes through the molten metal of the alloyed steel. The equations are given for non-stationary heat conduction, initial and boundary conditions for determining the temperature fields of main strip and cladding layer when obtaining a three-layer bimetallic strip on the unit of a combined process of continuous casting and deformation. The values of density, thermal conductivity and heat capacity for steel St3 were determined in a given temperature range. A procedure is described for calculating temperatures in the ANSYS package by solving a non-stationary heat conduction problem in a flat formulation by the finite element method. The authors have described the geometric model for calculating the temperature of strip and molten metal of the cladding layer. Values of the coefficient of heat transfer between the main strip and molten metal of the cladding layers of bimetallic strip are given adopted for calculation. Characteristic points are indicated in the model for calculating the temperatures of main strip and molten metal of the cladding layer. The graphs show temporal changes in these temperatures at production of a three-layer bimetallic strip on the unit of combined process of continuous casting and deformation. Calculated data on the time variation of temperature of main strip and molten metal of the cladding layer at characteristic points are given for different values of the contact heat transfer coefficient. © 2019 National University of Science and Technology MISIS. All rights reserved.

We considered the problem of obtaining upper bounds for the mathematical expectation of the $q$-norm ($2\leqslant q \leqslant \infty$) of the vector which is uniformly distributed on the unit Euclidean sphere. We finish the paper with numerical experiments illustrating our results., Comment: in Russian, 10 pages, 2 figures

The paper presents a comparative overview of decentralized data storages of various types. It is shown that although they have a number of common properties that are typical of all peer-to-peer (P2P) networks, the problems to be solved and, accordingly, the technologies used to build different types of storages differ significantly., 19 pages, 1 figures, 87 references; in Russian

The weighed and unweighted minimal set-cover problem, its applicability for the solution of the major optimization practical tasks, such as arrangement of service points, assignment of crews in transport, as well as the integrated-circuit and conveyer lines designing is considered. The paper objective is to describe methods of improving efficiency of this task solution. The principle of operation of the genetic algorithm and the applicability of its modification as a method of the solution to the set-cover problem are defined. Greedy strategy of Chvatal for the set-cover problem solution is considered. An exhaustive algorithm as an exact algorithm for the solution of small-size tasks is developed. The modified genetic algorithm developed by Nguyen M. H. is described. A software tool for comparing the performance of these algorithms is created. It is concluded that the solution of the set-cover problem by our genetic algorithm modification is more effective than by the genetic algorithm of Nguyen M. H. or the greedy strategy. And the results obtained in small-size tasks are noted for insignificant error.

The study focuses on the Russian regions’ disparities in the level of budget expenditures per capita and their dynamics. The paper assesses contribution of main factors and their correlation, as well as the stages of budget process, to the regional imbalances in the public sector. The author also presents regions’ budget expenditures per capita in a form of five-factor multiplicative model which at the same time demonstrates the sequence of the stages of budget process. To estimate regions’ inequality in budget expenditures and other related variables the researcher employs the Theil - Bernoulli index which is sensitive to excessive poverty. Its decomposition, made on the basis of the Duro and Esteban technique, allows evaluating the structure of inter- regional disparities in the public sector. The results include following: 1) static assessments of the factors contribution to the regions’ convergence in budget expenditure per capita at the stages of GRP production, receipt and distribution of taxes among levels of budget system, the stages of attraction of inter-budgetary support and budget deficit financing; 2) dynamic assessments of the factors contribution to regions’ convergence / divergence in the level of budgetary expenditure per capita for 9 years. The findings may be useful in optimizing the policy of inter-budgetary equalization in Russia

Nonahydro-closo-nonaborate anion possess the property of structural nonrigidity because of presence of three low-coordinated boron atoms. So it’s able to come into the reactions of polyhedral extension. This paper is devoted to the reactions of homoatomic polyhedral extension in nonahydrocloso-nonaborate anion [B9H9]2- in presence of triethylaminborane complex BH3·(C2H5)3N. It was shown that mixes of [B10H10]2- and [B12H12]2- salts in various molar ratios had been formed as products. These ratios depend on proportion of reagents. In presence of excess of triethylamin borane complex the molar ratio of products is 1:1. When equimolar amount of triethyamminborane complex used, the selectivity of process shifted to formation of [B10H10]2- anion. However the formation of [B12H12]2- still occurs in this conditions but the molar ratio of [B10H10]2-:[B12H12]2- is 5:1.

An approach to territorially localized innovation clusters as large-scale economic systems with an institutional component in their structure is developed in this paper. The approach is methodologically based on the G.B. Kleiner’s system paradigm according to which systems can be presented as a set of four elements – objects, environments, processes, and projects. Identifying institutions as systems allows incorporate the institutional component in the system paradigm. Taking into account the possibility for four-element representation of institutions as systems, the institutional features of such largest innovation clusters as Russian Skolkovo and American Silicon Valley are considered.

High-purity hydrogen is required for clean energy and a variety of chemical technology processes. A considerable part of hydrogen is to be obtained by methane conversion. Different alloys, which may be wellsuited for use in gas-separation plants, were investigated by measuring specific hydrogen permeability. One had to estimate the parameters of diffusion and sorption to numerically model the different scenarios and experimental conditions of the material usage (including extreme ones), and identify the limiting factors. This paper presents a nonlinear model of hydrogen permeability in accordance with the specifics of the experiment, the numerical method for solving the boundary-value problem, and the results of parametric identification for the alloy V85Ni15.

The aim of the study is establishing the possibility of using Zn nanotube arrays as a basis for design compact and lightweight elements of flexible electronics, including operating under influence of ionizing irradiation.The paper presents the results of the synthesis of Zn nanotubes obtained by electrochemical deposition in the pores of polymer matrices and the study of their structural and electrophysical properties after directional modification by ionizing radiation with different doses. Using the methods of scanning electron microscopy, X-ray diffraction and energy dispersive analysis, the structure of nanotubes having a polycrystalline structure and completely consisting of zinc was studied and it was demonstrated that irradiation with Ar8+ ions with a dose from 1 × 109 to 5 × 1011 ion/cm2 and energy 1.75 MeV/nucleon has an effect on the crystal structure of nanotubes.At high doses, localized highly defect zones arise, leading to a critical change in the structure and physical properties of the nanotubes, respectively. It is shown that the consequence of the modification of the crystal structure is a change in the electrical conductivity of nanotubes: at low doses the electrical conductivity increases, but when the threshold value is reached, it sharply decreases. The change in the crystal structure and the corresponding changes in the conductive properties of Zn nanotubes due to irradiation determine the mechanism of ionizing radiation influence on nanomaterials and determine the possibility of using Zn nanotubes arrays as a basis for creating compact and lightweight elements of flexible electronics.

Purpose. In this paper, for simultaneous placement of distributed generation (DG) and capacitors, a new approach based on Spring Search Algorithm (SSA), is presented. This method is contained two stages using two sensitive index Sv and Ss. Sv and Ss are calculated according to nominal voltage and network losses. In the first stage, candidate buses are determined for installation DG and capacitors according to Sv and Ss, Then in the second stage, placement and sizing of distributed generation and capacitors are specified using SSA. The spring search algorithm is among the optimization algorithms developed by the idea of laws of nature and the search factors are a set of objects. The proposed algorithm is tested on 33-bus and 69-bus radial distribution networks. The test results indicate good performance of the proposed method., Цель. В статье для одновременного размещения распределенной генерации и конденсаторов представлен новый подход, основанный на «пружинном» алгоритме поиска (Spring Search Algorithm, SSA). Данный метод состоит из двух этапов с использованием двух показателей чувствительности Sv и Ss. Показатели чувствительности Sv и Ss рассчитываются в соответствии с номинальным напряжением и потерями в сети. На первом этапе определяются шины-кандидаты для установки распределенной генерации и конденсаторов согласно Sv и Ss. Затем, на втором этапе размещение и калибровка распределенной генерации и конденсаторов выполняются с использованием алгоритма SSA. «Пружинный» алгоритм поиска входит в число алгоритмов оптимизации, разработанных на основе идей законов природы, а факторы поиска представляют собой набор объектов. Предлагаемый алгоритм тестируется на радиальных распределительных сетях с 33 и 69 шинами. Результаты тестирования показывают хорошую эффективность предложенного метода.

This paper proposes a method for measuring the position of radiation centers for an ultra-wideband combined antenna (CA) in the pulsed mode. The radiation centers for E- and H-planes of the antenna are determined. Antenna rotation in these planes, with respect to an arbitrary axis, results in the time delays (advances) of the recorded receiving pulses for various angles. The purpose of the measurements is to find the rotation axes providing minimum time delays of the radiated pulse registration at the receiving antenna for the largest possible range of observation angles. These rotation axes pass through local areas (radiation centers) in the antenna volume. Simple analytic formulas refining the position of the radiation center from an arbitrary measurement are proposed. In the simulations, a code based on the FDTD method was used. The CA has at least two radiation centers. Radiation center of the H-plane is located at 1/3–1/2 of the antenna length counting from its rear wall, slightly below the antenna’s half height. Radiation center of the E-plane is located near the aperture plane of the antenna, also slightly below the antenna’s half height.

Consumer behavior is perceived as an investment which does not yield results in the short run. The traditional economic theory of customer preferences is based on four main elements: customer income, the market price of goods, customer preferences, and behavioral assumption about the maximum of achievable benefits. Even though it sometimes might seem that equalizing energy consumption with behavior is not possible, it can often be described as consequences of behavior, such as turning off the lights or thermostat level reduction for saving power. Our paper demonstrates how the psychological concept of consumer behavior effects energy consumption. It provides recommendations about the incorporation of the idea of uncomplicated information availability for consumers taking into consideration their long-term habits. The novelty of this study is that psychological concept of consumer behavior effects energy consumption in each of the region, therefore, it is recommended to incorporate the idea of uncomplicated information availability for consumers taking into consideration long-term habits. The problem analyzed in the article is how consumer behavior influences energy consumption. The aim of the article is to analyze the consumer behavior in energy consumption. The objectives of the study are two-fold: i) to analyze the element of consumer behavior from the theoretical point of view, and ii) to investigate the patterns of energy consumption. The methods of the study are a logical and comparative analysis of literature, graphics, synthesis, and deduction. Our results and findings can be used by the stakeholders and policy-makers in preparing regional development economic policies and in designing the energy consumption strategies in the framework of the regional development. © Varanavicius V., Navikaite A., Bilan Yu., Strielkowski W. Text. 2017.

The paper introduces and investigates partial orders that are finer than the minus partial order and are based on inverses along an element and other specific outer inverses. It turns out that in this way a number of classical partial orders can be equivalently defined.

Введение. Статья предоставляет обзор научных открытий, касающихся магнитотак-тических бактерий (МТБ). Результаты открытий используются в микробиологии, минералогии, лимнологии, физике, биофизике, химии, биохимии, геологии, кристаллографии и астробиологии. Магнитосомы МТБ организованы в линейные цепи и ориентируют клеточные тела вдоль силовых линий геомагнитного поля, причем вращательные движения жгутиков приводят к т. н. магнитотаксису. Материалы и методы. Обзорная статья о бактериях, чувствительных к магнитному полю, является компиляцией нескольких научных работ из различных научных учреждений. Наиболее важные моменты этого обзора сводятся к следующим положениям: 1) любая биологическая система способна создавать магнитные биоматериалы, такие как магнетит (Fe3O4) и грегит (Fe3S4); 2) навигация этих нанокристал-лов в биологической системе взаимосвязана с магнитным полем Земли. Результаты исследования. Исследователи, участвующие в изучении данной темы, показали, что магнитотактические бактерии действительно реагируют на магнитное поле. Это делает их привлекательными для медико-биологического и промышленного использования из-за наличия сильных электромагнитов, сверхпроводящих магнитов и постоянного магнита. Магнетические бактерии также могут быть использованы в качестве диагностического инструмента при обнаружении дефектов даже на наноуровне. Обсуждение и заключения. Несмотря на важность этой темы, которая пока находит лишь ограниченное применение в медицинской области, необходимо исследовать мир этих бактерий, которые являются кандидатами для использования в новых промышленных технологиях и терапевтических стратегий в медицины.Introduction. This outline explores the scientific discovery concerning the magnetotac-tic bacteria (MTB). The results of the discovery are used in microbiology, mineralogy, limnology, physics, biophysics, chemistry, biochemistry, geology, crystallography, and astrobiology. Magnetosomes of the MTB are organized in linear chains and orient the cell body along geomagnetic field lines while flagella actively propel the cells, resulting in so-called magnetotaxis. Materials and Methods. The review article about the magnetotactic bacteria is a collection of many research papers from different institutes. The emerging important points about this review lie in: (1) any biological system is capable of producing magnetic biomaterials such as magnetite (Fe3O4) and gregite (Fe3S4); (2) the navigation of these nano-crystals in the biological system is interconnected with the Earth's magnetic field. Results. The researchers involved in the study have shown that the magnetotactic bacteria do respond to a magnetic field. This makes them attractive for biomedical and industrial applications because of the availability of superior electromagnets, superconducting magnets and permanent magnet. Magnetic bacteria can also be used as a diagnostic tool in the detection of imperfections even at the nanoscale. Discussion and Conclusions. Although the importance of this issue is still limitedly used in medical area, more performance is necessary to explore the world of these bacteria that are candidate for new industry and new therapy strategies in biotechnology and medical fields.

Срок службы большинства технических сооружений и их компонентов, как известно, зависит от наличия дефектов, таких как отверстия, трещины или пустоты, которые обычно возникают в ходе производственного процесса. Во многих случаях разрастание, расширение и распространение трещин в теле, по-прежнему, остается сложной проблемой в механике разрушения. В статье предложена расширенная аналитическая модель, основанная на секционном методе, в целях прогнозирования направления трещин и вычисления фактора интенсивности напряжений для треснувшего вала в условиях нагрузки смешанного типа. Преимущество настоящей формулировки, в основном, связано с ее способностью прогнозировать направление распространения трещин внутри вала в условиях сочетающегося продольного, изгибного и крутильного нагружений. Аналитические результаты непосредственно сравниваются с теоретическими выражениями из имеющихся справочников и численными решениями, полученными с помощью расширенного метода конечных элементов. Данный подход достаточно хорошо согласуется с теоретическими и численными результатами, предложенными в литературе, подтверждая тем самым его потенциал для точных расчетов распространения трещин и факторов интенсивности напряжений в валах произвольной конфигурации.The lifetime of most engineering structures and components is known to depend on the presence of defects, such as holes, cracks or voids usually introduced during a manufacturing process. In many cases, the crack growth, extension and propagation within a body, still remains a challenging problem in fracture mechanics. The present paper proposes an extended analytical model based on a section method to predict the fracture direction and compute the stress intensity factors for a cracked shaft under mixed-mode loading conditions. The advantage of the present formulation is mainly related to its capability of predicting the direction of crack propagation within a shaft under coupled longitudinal, flexural and torsional loading conditions. The analytical results are straightforwardly compared with the theoretical expressions available from the handbooks and the numerical solutions found with the extended finite element method. The present approach agrees quite well with the theoretical and numerical results already proposed in the literature, thus confirming its potentials for accurate computations of the crack propagation and stress intensity factors for arbitrary configurations.

This paper presents the results on the development of theoretical methods of evaluation and prediction of mechanical properties of Zr–Nb alloys over a range of strain rates from 10−3 to 103 s−1. The mechanical behavior of coarse- and ultrafine-grained Zr–1Nb (E110) was investigated numerically. The ranges of strain rates and temperatures in which the mechanical behavior of Zr–1Nb alloy can be described using modified models of Johnson–Cook and Zerilli–Armstrong were defined. The results can be used in engineering analysis of designed technical systems for nuclear reactors.

The aim of the paper is to highlight, if not all, then at least the most important benefits of the application of mathematical modeling in the development of a new solution or in the process of improvement and the optimization of an existing product. The thesis presents the basic principles of the model creation without providing a detailed mathematical interpretation of the process; therefore, the model includes a substantial number of unknown or approximately known parameters and it is not possible to create a model of the transparent cybernetic box type. In order to achieve a synthesis of the model and the experimental results, it is necessary to apply the optimization methods for the identification of unknown model parameters. The thesis presents the experimental results along with the results of modeling and identification as well as the analysis of the process of identification of unknown model parameters.

The present paper deals with investigation of the possibility for application of laser welding-on technology for repairing the mold cavities of die casting dies. The surface of the samples, made of 32CrMoV12-28 (DIN) steel, was welded on by additional material – maraging alloy with chemical composition 0.02С–19.3Ni – 0.4V–2Cr-14.5Co–4.7Mo–0.25Al–0.2Mn–0.2Si, (wt %). The surface treatment was done by pulse laser AL 200 Nd:YAG with a wave length of 1064 nm. To estimate the possibility for additional hardening of the welded-on layers, the samples were heated for 1 hour at temperatures of 450, 500, 550 and 600 °С. The microstructure was investigated by light microscopy, the Vickers microhardness was measured with 100 g load and XRD-analysis was done. After laser welding-on the hardened surface layer was obtained. Its microstructure possesses dendrite morphology and consists mainly of ferrite oversaturated with alloying elements. The intermetallic compounds of the types Fe-Cr and Fe-Al are also observed. After ageing Ni-Al and Ni-Mo phases precipitate with maximal quantity at a temperature of 550 °C. After ageing at this temperature a maximal hardness of 600–650 HV, twice higher than that of the welded-on layer, was observed. The next temperature increase leads to the hardness decrease up to 400–450 HV due to the interruption of the coherent bonds between the phases and transformation of dendrite morphology to equiaxed crystals. As a result of the present investigation the application of the laser welding-on with additional material – maraging alloy, could be recommended for repairing the mold cavities of die casting dies.

The paper presents the results of the experimental research of thermal properties (thermal conductivity, heat capacity, density and temperature diffusivity) of nitrogen- and oxygen-containing liquids in pure form and in the form containing 0.5 % fullerene-like carbons and carbon nanotubes with diameter d = 40 nm, 50 nm, 60 nm) in the temperature range 293–453 K and in the pressure range 0.101–49.01 MPa. To measure thermal conductivity, heat capacity and temperature diffusivity, special setups designed by professors E.S. Platunov, M.M. Safarov and I.F. Golubev were used. The computer-aided method of monotonous heating and regular thermal first-order regime was applied. The total relative error of measuring thermal conductivity, heat capacity, density and temperature diffusivity was equal to 2.6, 3.4, 0.1, 4.5 % when confidence probability α = 0.95. Using the law of corresponding states and experimental data on thermal conductivity, heat capacity, density and temperature diffusivity of the samples, the empirical equation for calculating the thermophysical properties of unexplored liquids under different temperatures and pressures was obtained.

A.A. Levin, Energy Systems Institute SB EAS (Irkutsk, Russian Federation), lirt@mail.ru, V.F. Chistyakov, Institute for System Dynamics and Control Theory SB RAS (Irkutsk, Russian Federation), chist@icc.ru, E.A. Tairov, Energy Systems Institute SB RAS (Irkutsk, Russian Federation), tairov@isem.irk.ru Левин Анатолий Алексеевич, кандидат технических наук, ведущий научный сотрудник, Институт систем энергетики им. Л.А. Мелентьева СО РАН (г. Иркутск, Российская Федерация), lirt@mail.ru. Чистяков Виктор Филимонович, доктор физико-математических наук, главный научный сотрудник, Институт динамики систем и теории управления СО РАН (г. Иркутск, Российская Федерация), chist@icc.ru. Таиров Эмир Асгадович, доктор технических наук, главный научный сотрудник, Институт систем энергетики им. Л.А. Мелентьева СО РАН (г. Иркутск, Российская Федерация), tairov@isem.irk.ru. This paper presents the results of applying the methods of the hydraulic circuit theory in the interactive modeling of hydrogasdynamic and thermal processes that occur in the equipment of thermal power plants. The problem statement of flow distribution in the energy plants with different pressure drop laws in the branches of complex gas air and steam-water ducts is formulated. The research shows that the application of traditional methods of hydraulic circuit theory is challenging for such problems. Some aspects of solvability of the related systems of nonlinear equations are studied. The numerical methods for solving these systems as applied to the problems that require calculations in real time are considered. A computation scheme is proposed. The scheme makes it possible to reduce the initial statement of the problem to the classical scheme of the nodal pressure method. The method of decomposition of the hydraulic circuit configuration into interconnected circuits of smaller dimension is considered to reduce the computational effort. The results of tests that demonstrate high reliability of the method developed for the flow distribution calculation are presented. В статье представлены результаты применения методов теории гидравлических цепей для интерактивного моделирования гидрогазодинамических и тепловых процессов в оборудовании тепловых электрических станций. Сформулирована постановка задачи расчета потокораспределения в трактах энергоустановок с различными законами падения давления на ветвях в сложных газовоздушных и пароводяных трактах. Показано, что применение традиционных способов расчета потокораспределения методами теории гидравлических цепей затруднительно для задач. Исследованы некоторые аспекты разрешимости соответствующих систем нелинейных уравнений. Рассмотрены численные методы решения этих систем применительно к задачам, требующим выполнения расчетов в масштабе реального времени. Предложена расчетная схема, позволяющая свести исходную постановку задачи к классической схеме метода узловых давлений. Рассмотрен способ декомпозиции структуры гидравлической цепи на взаимосвязанные цепи меньшей размерности для уменьшения вычислительных затрат. Приведены результаты тестов, демонстрирующих высокую надежность разработанного способа расчета потокораспределения. This work has been supported by the Russian Foundation for Basic Research, grant No. 15-01-03228-a.

The paper proposes a hybrid model, FAHP-MABAC. The fuzzyficated Saaty's scale with the AHP method (FAHP) is used for defining the weight coefficients of criteria. The MABAC method is applied in evaluating and ranking the alternatives. This hybrid model is developed in order to support decision making while selecting locations for the preparation of laying-up positions (facilities intended for concealment, protection and maneuvering of military ships).

Anastasiya Karavay - Research Fellow, Center for Economics of Lifelong Learning, Institute of Applied Economic Research, Russian Presidential Academy of National Economy and Public Administration. Address: 82 Vernadskogo Ave., 117606 Moscow, Russian Federation. E-mail: karavayav@yandex.ruIn this paper, we analyze the rates of participation of Russian workers in continuing professional education (CPE) using Rosstat data and sociological surveys, including the 2014 and 2015 Eurobarometer in Russia. We reveal considerable differences in the percentages of workers covered by CPE across age cohorts, personnel categories, and especially industries. Our analysis shows that formalized CPE norms and standards in such industries as education and healthcare have a largely positive effect on the incidence of employee participation in advanced trainings. Next, we demonstrate that the data collection methods used by Rosstat do not allow for a comprehensive analysis of CPE participation rates in all industries, as only large and medium-sized companies are covered by the official statistics, while small businesses, which form the best part of the retail sector, are left out. Besides, the rigid regulatory framework of the official statistics makes it impossible to embrace the diversity of existing types and forms of CPE. There is no single method to measure the rate of participation in continuing education (not only professional), which we demonstrate in our review of methodologies used by Russian and foreign researchers. As a result, comparing the rates of participation in lifelong learning (including CPE) in different countries becomes a challenging task.

Purpose.In the paperit isnecessary to analyze possibility of improving the positioning accuracy of train on the approach section to crossing for traffic safety control at railway crossings.Methodology. Researches were performed using developed mathematical model, describing dependence of the input impedance of the coded and audio frequency track circuits on a train coordinate at various values of ballast isolation resistances and for all usablefrequencies.Findings. The paper presents the developed mathematical model, describing dependence of the input impedance of the coded and audio-frequency track circuits on the train coordinate at various values of ballast isolation resistances and for all frequencies used in track circuits. The relative error determination of train coordinate by input impedance caused by variation of the ballast isolation resistance for the coded track circuits was investigated. The values of relative error determination of train coordinate can achieve up to 40-50 % and these facts do not allow using this method directly for coded track circuits. For short audio frequency track circuits on frequencies of continuous cab signaling (25, 50 Hz) the relative error does not exceed acceptable values, this allow using the examined method for determination of train location on the approach section to railway crossing.Originality.The developed mathematical model allowed determination of the error dependence of train coordinate by using input impedance of the track circuit for coded and audio-frequency track circuits at various frequencies of the signal current and at different ballast isolation resistances.Practical value.Theauthors proposethe method for train location determination on approach section to the crossing, equipped with audio-frequency track circuits, which is a combination of discrete and continuous monitoring of the train location.&nbsp

One of the most promising methods for manufacture of axially symmetric parts such as disks or hollow shafts of gas turbine engines is local deformation using cold rolling. Physical and mathematical modeling can be quite effective for designing this class of equipment and process operations. This article presents the methodology and results of physical and mathematical finite element modeling of local deformation of parts such as a tapered cylinder fabricated from chromium steel alloy grade 11H11N2V2МF-Sh. Chemical elements in the alloy are designated by the letters which stand for: H – Chromium, N – Nickel, V – tungsten, M – molybdenum, F – vanadium, Sh – electroslag remelting. According to GOST 5632-72 (Russian standard), this type of nickel-chromium alloy consists of about 11 % of chromium, 1.5–2 % of tungsten and nickel, up to 1 % of molybdenum and vanadium, and 0.11 % of carbon, hundredths of one percent of phosphorus and sulfur. It is heat-resistant high-grade steel, which is used for the manufacture of parts operating unloaded at 900–1000 °C. The purpose of the paper is to analyze the process energy-power parameters and possible fracture of parts during deformation.

Purpose. The work proposed for the modeling of transients in Lehera line uses a modified Hamilton-Ostrogradskiy principle. The above approach makes it possible to avoid the decomposition of a single dynamic system that allows you to take into account some subtle hidden movements. This is true for systems with distributed parameters, which in the current work we are considering. Methodology. Based on our developed new interdisciplinary method of mathematical modeling of dynamic systems, based on the principle of modified Hamilton-Ostrogradskiy and expansion of the latter on the non-conservative dissipative systems, build mathematical model Lehera line. The model allows to analyze transient electromagnetic processes in power lines. Results. In this work the model used for the study of transients in the non-working condition Lehera line. Analyzing the results shows that our proposed approach and developed based on a mathematical model is appropriate, certifying physical principles regarding electrodynamics of wave processes in long power lines. Presented in 3D format, time-space distribution function of current and voltage that gives the most information about wave processes in Lehera line at non-working condition go. Originality. The originality of the paper is that the method of finding the boundary conditions of the third kind (Poincare conditions) taking into account all differential equations of electric power system, i.e. to find the boundary conditions at the end of the line involves all object equation. This approach enables the analysis of any electric systems. Practical value. Practical application is that the wave processes in lines affect the various kinds of electrical devices, proper investigation of wave processes is the theme of the present work., В работе, на основе обобщенного междисциплинарного (интердисциплинарного) метода математического моделирования, основанного на модификации интегрального вариационного принципа Гамильтона-Остроградского, предложена математическая модель двухпроводной длинной линии электропередач, которая работает на холостом ходу. Представлены результаты компьютерной симуляции переходных процессов в виде рисунков, которые анализируются.

Sociology can analyze war and warfare under different aspects, for example, as a problem of collective violence. It has rather neglected another important aspect of war, as in the fact that war is also always an organizational phenomenon. In the last few years, several studies on war have been focusing on this aspect by using or referring to Niklas Luhmann’s system theory. This paper looks at some of these aspects by critically asking how these sociological studies use Luhmann’s theory in their analysis of war or war-related social structures. Luhmann’s theory, particularly the theory of society based on the principle of functional differentiation, has a powerful explicative potential, particularly for the analysis of war and warfare. However, only a few studies are actually using Luhmann’s theory in an adequate way by situating the concepts at the correct analytical level. War and “military systems” should be analyzed as organizational structures in society which are managed, first of all, by the political system, a function system of society, and which by no means excludes a multiplicity of interdependencies with other systems. A systemic perspective should also take regional “expressions” of society such as “military systems” in specific states or groups of states into account., Социология может анализировать войну с различных сторон, например, как проблему коллективного насилия. Достаточно часто игнорировался еще один важный аспект войны — тот факт, что она всегда еще и организационное явление. В последнее время некоторые исследования войны фокусировались на данном аспекте, используя или упоминая системную теорию Н. Лумана. В настоящей статье критически рассматривается некоторые из этих исследований с точки зрения того, как теория Лумана используется при анализе войны или связанных с войной социальных структур. Теория Лумана, в частности, его теория общества, основанного на принципе функциональной дифференциации, обладает мощным объяснительным потенциалом, в особенности для анализа войны и военных действий. Однако лишь немногие исследования действительно адекватно применяют теорию Лумана, располагая понятия на должном аналитическом уровне. Война и «военные системы» должны быть проанализированы как организационные структуры общества, управление которыми осуществляется, в первую очередь, политической системой — функциональной системой общества, которая, в свою очередь, никоим образом не исключает множества взаимосвязей с другими системами. Системная перспектива должна также учитывать региональные особенности общества, такие, как «военные системы» в конкретных государствах или объединениях государств.

This paper focuses on a finite element implementation of the sampling surfaces (SaS) method for the three-dimensional (3D) stress analysis of functionally graded (FG) laminated elastic and electroelastic shells. The SaS formulation is based on choosing inside the nth layer n I not equally spaced SaS parallel to the middle surface of the shell in order to introduce the electric potentials and displacements of these surfaces as basic shell variables. Such choice of unknowns permits the presentation of the proposed FG shell formulation in a very compact form. The SaS are located inside each layer at Chebyshev polynomial nodes that improves the convergence of the SaS method significantly.

The paper demonstrates the feasibility of obtaining materials based on molybdenum disilicide through the combination of combustion process and shear deformation of the synthesis products. It has been established that mechanical treatment affects combustion processes, phase and structure formation of materials, resulting in the change of grain size, morphology and quality of the finished product. Shear deformation at SHS leads to almost 100 % output of powder of a fineness of less than 500 microns.

The present paper reports on a study of kinetic parameters of the adsorption of the Methyl Orange organic dye from aqueous solutions on nanomodified and non-modified carbon materials under static conditions. Commercially available NWC coconut shell-based activated carbon was used as a pristine adsorbent. It was modified with multi-walled carbon nanotubes to obtain a nanomodified material. These carbon nanotubes were synthesized via chemical vapor deposition over a metal-oxide catalyst prepared by a citrate sol-gel method. A spectrophotometric method was used to determine Methyl Orange concentrations (at wavelength of 400 nm). For each type of adsorbents (nanomodified and non-modified activated carbon), chemical interactions between its surface functional groups and the dye were observed. The adsorption kinetics for both types of activated carbons were analyzed by pseudofirst and pseudosecond-order models, which were well-described by the pseudosecond-order model with a correlation coefficient of about 0.99. Besides, adsorption rate constants were calculated using kinetic models. It was found that equilibrium of the Methyl Orange adsorption on the nanomodified carbon is achieved 1.5 times faster than that of the Methyl Orange adsorption on the pristine carbon, and the adsorption capacity of the former is 2.1 times higher than that of the latter one. These findings suggested that the activated carbons could be regarded as a promising adsorbent for the removal of the organic dye – Methyl Orange – from wastewaters.

In this paper, we consider methods for hyperspectral image processing, required in systems of image formation, storage, and transmission and aimed at solving problems of data compression and protection. A modification of the digital image compression method based on a hierarchical grid interpolation is proposed. Methods of active (on the basis of digital watermarking) and passive (on the basis of artificial image distortion detection) data protection against unauthorized dissemination are developed and investigated.

In this paper, we consider iterative propositional calculi, which are finite sets of propositional formulas together with the rules of modus ponens and weak substitution (when formula being substituted must be already inferred). We construct an undecidable iterative propositional calculus using axioms in 3 variables. Particulary, we show that the general problem of derivability for these calculi is undecidable., 10 pages, in Russian

This paper presents a numerical study on the frictional contact between two crossed fibers subject to both normal and tangential oscillation. The results from simulation using the method of dimensionality reduction show that the frictional energy dissipation increases firstly with coefficient of friction, and then almost symmetrically decreases to a constant. The fiber aspect ratio has an important effect on the energy dissipation and this effect becomes more significant for larger coefficient of friction. The simulation results for very large coefficient of friction show a good agreement with the analytical solution for the case of infinite coefficient of friction.

This paper analyzes vacuum plasma spray VPS - Cr3C2 - 25(Ni20Cr) coatings. Commercial powder marked Sulzer Metco Woka 7205 is used. The powder is deposited with a plasma gun F4 at a distance of 340 mm from the substrate. The main objective of the study was to eliminate, at the reduced pressure of inert gas Ar, the degradation of primary Cr3C2 carbide into Cr23C6 carbide which significantly reduces the microhardness and mechanical properties of the coating. The coating is deposited with a thickness of 100 - 120 μm on a steel substrate. The microhardness of the coating was tested by HV0.3. The microhardness values were in the range of 1248 - 1342 HV0.3. The bond strength of the coating was tested by tension. It was found that the bond strength between the substrate and the coating has a value of 89 MPa. The microstructure of the coating was tested by the light microscopy technique. The structure of the coating consists of an NiCr alloy base with a dominant primary Cr3C2 carbide phase. In addition to the Cr3C2 phase, the Cr7C3 phase is also present. The coating etching was done with the reagent 1HNO3 : 4HCl : 4H2O that primarily dissolves nickel to enable the distribution of the carbide phase to be clearly seen in the coating. Etching the coating with this reagent revealed the presence of the largely undegraded primary Cr3C2 carbide phase which provides high hardness values to the coating.

International audience; In this paper we show that the upper bound 2n - 2 on the length of input sequences that distinguish two sets of states is tight for a non-observable NFSM with n states and a polynomial number of inputs and outputs. For each n>=2, there exists a non-observable NFSM M with n states, a single input symbol, and n output symbols such that there are two sets of states in M which are not distinguishable by each input sequence of length 2n - 3 but can be distinguished by an input sequence of length 2n - 2.