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Our ongoing research is dedicated to the development of a method of computer-aided hyper-hyponymic verbal pairs extraction from dictionary definitions. Syntactic signals provide important information for the task. The main advantage of syntax-based method is that it allows one to distinguish hypernyms from synonyms, which is very difficult for distributional methods such as word embeddings as long as hypernyms and synonyms both tend to occur in similar contexts. This paper focuses on extrinsic evaluation of all three UDPipe pre-trained models for the Russian language. It is shown that despite high performance on different corpora the models' perform poorly on our highly specific corpus consisting of dictionary definitions of verbs. [ABSTRACT FROM AUTHOR]

The paper studies dynamic model of interacting populations of the type "predator - two preys". A detailed analysis of the oscillation regime is carried out. Under the conditions of the bifurcation parameter, where coexisting of oscillatory and equilibrium regimes is detected, separable surfaces are constructed. This surface is the boundary of the basins of their attraction. It is shown that the influence of an external random disturbance can destroy the oscillatory regime of coexistence of three populations and lead to the extinction of two populations. Using the stochastic sensitivity function, probabilistic mechanisms of destruction of oscillatory regimes are manifested. [ABSTRACT FROM AUTHOR]

Using a reduced set of facial keypoints improves the accuracy of calculating the angles of rotation of the head. In this paper, we propose methods for evaluating the accuracy of calculating angles and an algorithm for selecting a subset of facial keypoints. This approach has improved the accuracy of angle calculation by more than 50%. [ABSTRACT FROM AUTHOR]

The perspective of using three-dimensional BIM design of buildings and constructions for atomic engineering with aim to optimize radiation protection of personnel and to create database at the stage of construction and operation. As an example considered the creation of pressure compensator tank rooms of decommissioned PWR (VVER-210) and process room with hydraulic strapping, shut-off valves and other equipment. There are two programm used in this report: AutoDesk Revit (for designing) and AutoDesk 3DS Max (for animation creating and rendering). [ABSTRACT FROM AUTHOR]

The convolutional neural networks with supervised training solve problems of semantic segmentation in a wide area of biomedical applications. However, this approach requires a significant size of the training dataset. Unsupervised learning can provide segmentation of some images without training dataset. Joint unsupervised learning is an approach that combines neural networks with another algorithm of data clusterization. In this preliminary study, we test the joint unsupervised learning approach with minor modifications for the problem of semantic segmentation at several datasets of biomedical images. [ABSTRACT FROM AUTHOR]

This article discusses the effect of the software–hardware complex for testing electronic means on the effect of electromagnetic interference. A functional diagram is presented with a detailed description of the functional catch. Methods of operation of the complex for generation of test signals for the analyzed article are described. The method of processing the obtained data with subsequent issuance of recommendations for rework of the article is also described. [ABSTRACT FROM AUTHOR]

Mathematical modeling of solidification processes is used in metallurgy and materials science since such methods allow determining the main features of the physical and mechanical properties of solidified substances. In some cases of solidification, the temperature of the metastable zone may significantly differ from the temperature of the equilibrium phase transition due to the supercooling effects and the resulting specific structures close to the moving crystallization front, such as the formation and growth of dendrites and nucleation effects. Taking into account the compensatory effects of latent heat generation, we present the development of the model and the results of modeling of the mushy zone for the case of TiAl melt and quasi-stationary solidification regime. [ABSTRACT FROM AUTHOR]

This paper compares the quality of segmentation of echocardiographic images of the left ventricle of the heart using 5 architectures and 38 pre-trained encoders. As part of the study, we trained 1140 neural networks. On the test dataset, the accuracy was 93.18% according to the Dice metric, which is more than our previous result at 92.78%. On cross-validation, the accuracy was 98.79%, which is higher than the previous result of 90.15%. [ABSTRACT FROM AUTHOR]

It is emphasized the importance of using radioisotope products in industry, science and medicine. Information is given on the generation of isotope products in the IVV-2M research reactor of Research Institute of Nuclear Materials, and the plans for expanding the range of radioisotopes produced. The features of the selenium-75 isotope production are described. The necessity of thermohydraulic simulation of the target for producing selenium-75 in the conditions of the IVV-2M reactor is substantiated. The process of constructing a solid-state model of the target and simulating the thermal conditions for the production of isotopes is described. In this work, the analysis of thermohydraulic processes was performed with Solidworks Flow Simulation software. [ABSTRACT FROM AUTHOR]

The paper considers the ways to reduce irradiation doses of nuclear power plants' personnel. A comparison of conventional and quick-removable thermal insulation was performed. The requirements for quick-removable thermal insulation are given. Comparative analysis of conventional and quick-removable thermal insulation was made relative to the labor costs for assembling and disassembling. The construction of the quick-removable combined radiation shielding and heat insulation for NNP's equipment and systems is proposed, which is intended to reduce irradiation doses by shielding and shortening the personnel stay time in radiation fields. [ABSTRACT FROM AUTHOR]

Recently, the thermal dendrites (fractal-like structures) on the surface of water have found with an infrared camera. Here these structures are modelled with ANSYS FLUENT software. [ABSTRACT FROM AUTHOR]

Obtaining valuable information about plasma properties inside tokamak chambers is often associated with processing a large amount of experimental data and requires significant time resources. This feature in the case of repeated experiments imposes certain inconveniences for researchers. The calculation of the spatial distribution of the radiation power density, as well as the integral radiation power of the plasma cord, is no exception in this regard. With the help of hardware tools of the functional-oriented programming environment LabVIEW, a software module was created whose task is to restore the radiation power density profile based on the Pierce method under the assumption of cylindrical symmetry of the plasma column, as well as the formation of an integral bolometric signal based on experimental data coming from a set of AXUV detectors. The developed software module allows you to automate the process of obtaining the material necessary for analyzing the dynamics of processes inside the tokamak chamber, as well as calculating parameters that are of fundamental importance in assessing the amount of impurities in the plasma, including lithium impurities. [ABSTRACT FROM AUTHOR]

In this study, a method for modeling a core structure by the packing of the spheres and sphere-polyhedra was considered. The influence of the dilatation procedure on the integral structure parameters was studied. This method is useful for the modeling of porous materials and for studying their filtration properties. [ABSTRACT FROM AUTHOR]

This work is the part of a study of the low-frequency acoustic effects on redox chemical reactions. We have investigated the effect of low-frequency axial vibrations on a model system consisting of two biochemically active components: the monomeric form of the dye methylene blue and ascorbic acid. The model system allows to study the effect of the field of low-frequency vibrations on the mutual redox process and to reveal the features of such effects. As a result of the study, the effect of inhibition of the model system in the field of low-frequency acoustic vibrations was discovered. The effect was quantified. The kinetic curves of the sound chemical process were obtained. [ABSTRACT FROM AUTHOR]

The paper studies the issue of implementation of supercomputer URAN and OpenMP technology for approximate construction of controllability sets of dynamic systems. The controllability set calculation module for the computing program OCPS was developed within the research. Further OCPS was used for a series of numerical experiments. The results of the experiments allowed to evaluate the prospects for using a supercomputer URAN as a computing tool for calculating controllability sets of dynamical systems in a Euclidean space of dimension 6. [ABSTRACT FROM AUTHOR]

The problem of minimizing the time of reloading nuclear fuel for the BN-800 reactor is considered. Time- optimal control algorithm is proposed under the assumption that plugs can rotate sequentially. [ABSTRACT FROM AUTHOR]

The influence of the electret on the properties of craft paper modified with polycaprolactone is shown in this article. When applying a polymer coating, a change in the surface properties of the pulp and paper material occurs, which is reflected in the wetting parameters. Processing pulp and paper materials in the field of a unipolar corona discharge leads to an increase in their mechanical characteristics and a decrease in roughness and air permeability. [ABSTRACT FROM AUTHOR]

The purpose of this work is to develop a software and hardware complex for evaluating the effect of an electrostatic discharge on electronic devices. This will make it possible to increase the effectiveness of methods for testing electronic devices for resistance to electrostatic discharges both at the level of components, the printing module, and at the level of the system as a whole. The object of research is the processes of the impact of electrostatic discharges on the design of electronic devices, their element base as well as methods for improving the effectiveness of protection against such undesirable effects. [ABSTRACT FROM AUTHOR]

Calculations and analysis of residual energy emissions in the storage pit of irradiated fuel assemblies of the IVV-2M research nuclear reactor and a 3D model of the passive heat removal system was developed. [ABSTRACT FROM AUTHOR]

Molecular dynamic simulation of helium diffusion within a ring dislocation inside a stoichiometric UO2 nanocrystal was carried out. Two different sets interaction potentials were used. One of the sets was characterized by a significantly stronger binding of helium to the crystal lattice. Temperature dependencies of the diffusion coefficient along the dislocation line were obtained. It was shown that the strengthening in the binding of helium led both to a decrease in the diffusion coefficient of the atom and to an increase in the temperatures at which the model dislocation was annealed. [ABSTRACT FROM AUTHOR]

Two alternative sets of interaction potentials of a xenon atom with the ionic environment in the plutonium dioxide crystal are compared with respect to the simulation of high-energy processes. It is shown that an increase in the hardness of the potentials at the interaction energies near and above 1000 eV significantly increases the fraction of energy transferred to xenon bubbles by collision cascades, also lowering the threshold energy of displacement of the xenon atom. [ABSTRACT FROM AUTHOR]

A simple mathematical model of UN, U2N3, and UN2 crystals is used for reconstructing the pair potentials of interaction of the nearest neighbors and subsequent molecular dynamics simulation. The corresponding parameters of the U−N potential in U2N3 and UN2 crystals are obtained from the experimental values of the lattice constant and the bulk moduli of UN, U2N3, UN2 at room temperature. The linear expansion coefficients of U2N3 and UN2 crystals, as well as the U2N3 bulk modulus are estimated within the harmonic approximation. The dependences of the U2N3 and UN2 lattice constants on temperature are calculated by the molecular dynamics method. [ABSTRACT FROM AUTHOR]

A technique has been developed for optimizing multiflow cascades to obtain highly concentrated intermediate molybdenum isotopes. A computational experiment was carried out to separate a mixture of molybdenum isotopes. Various cases for the separation of molybdenum isotopes in cascades with large step separation coefficients corresponding to gas centrifuges were considered. It is shown that using of the bee swarm optimization has an advantage over the Hook-Jeeves method. [ABSTRACT FROM AUTHOR]

This study reports a behavior of the magnetic and electrical properties, as well as hardness and microhardness, of GP1 steel samples built in vertical and horizontal directions. The hardness, electrical and magnetic properties of the samples were determined to be extremely different. The as-built vertical sample properties were found to be inhomogeneous. The properties of the as-built horizontal sample were uniform. The heat treatment (650 °C for 1 hour) allowed the vertical built sample to become homogeneous. This fact can be associated with the thermal stress revealing. The obtained results show that the magnetic properties are suitable for non-destructive testing (NDT) of the hardness and the phase composition of the 3D samples. The results of this study can be used in NDT practice. [ABSTRACT FROM AUTHOR]

The strength of the main elements of the mill such as: rolls, pillows, bearings, a pressure device, a bed is determined. Moreover, all elements except the bed satisfy the strength condition for maximum rolling force. The stand rigidity, which largely determines the probability of obtaining the required rolled metal dimensions and various deviations in shape, is also defined. In accordance with the calculation, the stand rigidity is insufficient for the cold rolling thin-sheet mills. [ABSTRACT FROM AUTHOR]

Magnetic and magnetoacoustic properties of low-carbon steel subjected to two-stage cold plastic deformation by rolling and subsequent flat pressing are studied. It is determined that the hardness and coercive force are changing non-monotonically with deformation degree increase. Shape change during flat pressing leads to partial softening of the samples that lost flatness during rolling. It is established that the softening of the material can be detected by the amplitude of the parameter interrelated with the shape of the major hysteresis loop. It is shown that the parameter proportional to the field of the maximum of magnetoacoustic emission could be a diagnostic parameter of the resulting hardening of steel as a result of two-stage plastic deformation. [ABSTRACT FROM AUTHOR]

The study is aimed to find and identify particles of polymer materials in contemporary urban surface deposited sediments (USDS). USDS reflect changes in the geochemical conditions that occur in the environment, and the USDS accumulates microplastic along with other pollutants. The search and identification of microplastics was conducted by Raman spectroscopy for two types of samples: granulometric subsamples obtained from USDS samples collected in Russian cities, and individual supposedly polymer particles collected from solid phase material of snow-dirt sludge samples. According to the analysis of Raman maps the particles of microplastic were not found in any sample of the granulometric subsamples from USDS. Individual particles from the solid material of snow-dirt sludge were identified as particles of polymer origin as other minerals and chemicals. The results obtained contribute to the scientific basis for the development of the effective system of regulation and control of pollution of the urban environment with polymer materials. [ABSTRACT FROM AUTHOR]

Scientific idea of the modeling is based on assumption of similarity in crystallographic lattice transformations for shear phase and structural transformations. Occurrence of orientation relationship between parent and final phases is based on parallelism of high density packed planes and directions. This results in phase nucleation on suitable boundaries «substrate». In case of structure transformations, the special misorientations play the role of the orientation relationships, while special boundaries play the role of substrates. The result of the study is knowledge based algorithms of control over texture formation in metal based materials resulted from crystallographically oriented phase and structure transformations focused on achievement of required combination of operational properties in product. [ABSTRACT FROM AUTHOR]

In the production of pipes, quality control is performed sequentially in several stages. First of all, it's an incoming inspection. The next step is non-destructive testing (NDT) in the production flow using devices (ultrasonic, eddy current or magnetic), periodic sampling and factory testing in laboratory (visual measurement, mechanical property determination, metallographic inspection of cross sections in the welded joint area). The final step is the non-destructive testing of measuring pipes (outgoing inspection) and hydraulic testing. This article presents the results of the study of the fragments of 48 mm longitudinal electric-welded pipes made of steel grade 10 in the post-production condition, in order to detect surface cracks of small opening, detected by visual inspection. [ABSTRACT FROM AUTHOR]

The polymer material was tested for resistance to chemical media, which were selected as: hydrochloric acid, acetic acid, sodium chloride solution, sodium hydroxide solution. After extraction from the test fluid and drying, to change in mass, size, and appearance of the samples was determined. [ABSTRACT FROM AUTHOR]

The qualitative and quantitative composition of the Bursa meteorite was determined, and populations of structurally nonequivalent positions in phases were found. Equations for clinopyroxenes are defined. [ABSTRACT FROM AUTHOR]

PAS spectroscopy is nowadays well recognized as a powerful tool of microstructure investigations of condensed matter. As a result of the experiments, data were obtained show the effect of cavitation on the occurrence of surface defects in a titanium alloy on various time characteristics. [ABSTRACT FROM AUTHOR]

A simple method for applying superhydrophobic coatings based on carbon nano-onions obtained by a low-cost and technological synthesis method is proposed. The dependence of the hydrophobic properties of the coating on the application conditions, surface roughness and parameters of nanoobjects is analyzed. [ABSTRACT FROM AUTHOR]

The aim of the work is to study the properties of a plane wave incident on a layered and periodic medium with a defective layer. A basic component of a computer program for calculating the reflection coefficient and transmittance of layered nanostructures has been created. An analysis of the defect in a periodic layered structure such as a photonic crystal is performed. [ABSTRACT FROM AUTHOR]

The attached transducer for local phase composition control of two-phase austenitic steels was made. Study of two-phase austenitic steels specimens was carried out. Clear relation between phase composition and maximal differential magnetic susceptibility was demonstrated for the suggested transducer. [ABSTRACT FROM AUTHOR]

This article is devoted to the study of vibrations that occur during metal cutting. The results of the study are necessary to create an adaptive system for CNC machines, which can control the parameters of metal cutting in real time. The article describes correlations related to the vertical component of the vibration acceleration of the cutting tool, the vertical component of the cutting force and the type of chips during turning. [ABSTRACT FROM AUTHOR]

The process of preparing porous composite ceramic material based on gadolinium zirconate, reinforced with ceramic fiber, including synthesis of a foam-cryogel with the addition of Gd2Zr2O7, the freezing-thawing, drying and sintering, was investigated. Microstructure and phase composition of porous Gd2Zr2O7 ceramics in connection with reinforcement using ceramic fibers are discussed. [ABSTRACT FROM AUTHOR]

The 57Fe NMR spectra have been obtained in carbon encapsulated iron nanoparticles. It has been shown that the cores of the nanoparticles consist of metallic α-Fe with base-centered cubic structure, carbide θ-Fe3C, carbon-iron solid solution α-FeCX and additional phase ε-Fe2C. Quantitative phase analysis has been performed with using complex of methods. [ABSTRACT FROM AUTHOR]

The orthorhombic Ruddlesden-Popper phase La2CuO4±δ with the Cmce space group was obtained by a solid-state reaction route. Thermochemical data were calculated for the reaction of lanthanum cuprate formation Thermogravimetric measurements show the oxygen content is close to stoichiometric. Cyclic CLOU experiment was carried out to determine a specific oxygen capacity (ΔWo exceeding 3.9%), as well as oxygen nonstoichiometry (δ) of La2CuO4±δ. The combustion rate of methane at 950 °C in the CLOU cycle about 0.5 l/min for one mole of lanthanum cuprate was achieved. [ABSTRACT FROM AUTHOR]

A process of developing a computer model for predicting distribution of oxide and carbide refractory particles during centrifugal casting using the ANSYS FLUENT 16.0 software module is presented. The model takes into account two liquid phases' interaction: air and steel melt; interfacial interaction is described by the surface tension equation. AISI 321 steel was used as the base metal, and tungsten, boron carbides and yttrium oxide as input particles. [ABSTRACT FROM AUTHOR]

The using possibility a unipolar corona discharge to improve the range of paper ashless filters operational properties has been investigated. It was revealed that the samples treatment by corona discharge led to an increase in the purity of the test filtrate, as well as to an increase in the strength characteristics of paper ashless filters. [ABSTRACT FROM AUTHOR]

Features of phase formation during the aluminothermal reduction of titanium from their dioxide were studied using the methods of thermodynamic modeling, X-ray phase and electron microprobe analysis. The interaction of aluminum with titanium dioxide proceeds through the stage of titanium monoxide formation. It is characterized by the formation of TixAIy intermetallides of different composition (TiAl3, TiAl, Ti2Al) depending on the ratio of Al and TiO2. [ABSTRACT FROM AUTHOR]

Nickel-indium alloys were considered as potential hydrogen storage materials. X-ray diffraction studies showed that with increase in the indium concentration in the Ni–In composite intermetallic phases were formed (InNi2, InNi3, In3Ni2, η-In27Ni10, InNi). Thermal desorption was used to quantify the content of hydrogen included in composites during their synthesis by the electrolysis method. Hydrogen peaks were observed at temperatures of 550 and 850 K. Mass spectroscopy was used to study the spectrum of thermal desorption of deuterium from Ni70In30-Dx composites, and the temperature ranges of desorption of ion-implanted deuterium were determined depending on the implantation dose. An increase in the content of implanted deuterium to 3×1018 D / cm2 leads to the formation of a solid solution of deuterium in the Ni70In30 composite, the decomposition temperature of which in vacuum is ∼ 530 K, and nickel hydride with hydrogen with a decomposition temperature of ∼ 350 K. The integral amount of desorbed deuterium was determined from the irradiation dose to 4 × 1018 D / cm2 for the Ni70In30 composite. The maximum concentration of deuterium is ∼ 2 at. D/at. Met., Corresponding to the ratio Met.: D2 = 1:2. The calculation of the activation energy of thermal desorption for a hydrogen peak with a maximum temperature of 500 K. The value of the activation energy for a peak with a maximum temperature of 500 K is 2.9 eV. [ABSTRACT FROM AUTHOR]

The atomic planes of a crystal cause an incident beam of X-rays to interfere with one another as they leave the crystal. This phenomenon is called X-ray diffraction (XRD). Crystals consist of planes of atoms that are spaced a distance d apart, but can be resolved into many atomic planes, each with a different d spacing. a, b and c (lengths) and α, β and γ are angles between a, b and c those are lattice constants (parameters) which can be determined by XRD. The 6061Al alloys is used as cladding for nuclear reactor fuel so it is very important to study the properties of this alloy by several techniques such as XRD. The aim of this work is using the XRD to study the crystal properties of 6061 Al-alloy which is used for cladding of nuclear fuel by determining the crystallite size, micro strain, defect density, etc. XRD device model no (202964) Operator (Beni Suef University) is used. The results indicate that the crystallite size of 6061 alloys decreases gradually from 0.388 to 0.075 with thickness reduction. Also, the micro-strain and the lattice parameter nearly constant for all degree of deformation only changes irregularly and there is a peak approximately at 9 % of thickness reduction due to the preferred orientation. The dislocation has an exponentially variation from 9.7 x108 cm−2 to 1.14 x109 cm−2. [ABSTRACT FROM AUTHOR]

The ZrO2 – 8 mol. % Y2O3 (8YSZ) и ZrO2 – 4 mol. % Sc2O3 – 4 mol. % Y2O3 (4Sc4YSZ) powders were prepared by the method of reverse co-precipitation with ammonia and nitrate-organic synthesis, respectively. The microstructure of powders is examined, their granulometric and phase composition, specific surface area are determined. The influence of synthesis conditions on the morphology of particles is revealed. The obtained powders are intended for the production of ceramic materials – an electrolyte and a carrier anode in solid oxide fuel cells. [ABSTRACT FROM AUTHOR]

Modern microbeam analytical instruments allow obtaining images and maps of heterogeneous minerals and synthetic materials in various signals with micron and submicron spatial resolution. Joint image analysis of several images allows getting more complete information about the sample that one image, but this joint analysis is usually subjective and is carried out at a qualitative level. Current study is devoted to the development of a joint quantitative analysis of images (JPD method) and its software implementation with the aim of more efficiently extracting information about the features of the internal texture and finding the correlation relationships of image characteristics with the physicochemical properties of samples that are in demand for settle issues of mineralogy and materials science. [ABSTRACT FROM AUTHOR]

The article focuses on developing an innovative method of predicting steel corrosiveness. The influence of heat treatment upon the corrosion rate and magnetic properties is revealed by corrosion tests of hot worked structural steel samples where the maximum corrosion loss was observed at the tempering temperature of 200°C. The correlation between magnetic properties of steels and their corrosiveness, which was confirmed by correlating the corrosion loss of the 45Х (45KH) steel and its magnetic parameters. An express method of scanning magnetic parameters was offered to spot potentially corrosive zones. An indirect correlation between magnetic parameters and corrosiveness is not necessarily unambiguous. A multi-parameter approach can be considered as a solution to the problem of ambiguity. Via the harmonic decomposition of magnetic hysteresis loops of 45X (45KH) steel samples, a range of odd harmonics was obtained, of which some correlate weakly with the corrosion loss. Sets of several harmonics correlate with it to a greater degree. Determining corrosiveness using magnetic parameters can be reduced to classical problems of diagnostic engineering. [ABSTRACT FROM AUTHOR]

The technology of producing composite ceramic coating based on zirconium dioxide has been developed. The method includes applying a ceramic material to metal substrates with a specially prepared surface. The sample was dried, calcined and sintered at 1200 °C in vacuum. [ABSTRACT FROM AUTHOR]

A potentiometric method for determining the antioxidant capacity of objects containing compounds of different hydrophilicity using the K3[Fe(CN)6]/K4[Fe(CN)6] system as an oxidizing agent is proposed. The developed method determines antioxidant properties of vitamin preparations containing compounds of different hydrophilicity, namely the ascorbic acid and the α-tocopherol. A comparative analysis of the amount of active substance have been made according to the data declared by the manufacturer and determined experimentally. [ABSTRACT FROM AUTHOR]

Temperature dependence of kinematic viscosity of Fe12Mn2C liquid alloy was determined. Results are discussed in context of microheterogeneity of FeMnC alloys within the framework of theory of absolute reaction rates. [ABSTRACT FROM AUTHOR]