Summaries of the Issue

OPTICAL ENGINEERING

SPECTRAL AND LUMINESCENT PROPERTIES OF DOPED AND CO-DOPED GLASSES BASED ON 35Bi2O3-40PbO-25Ga2O3 COMPOSITION Klinkov Victor A., Semencha Alexander V. , Vladimir A. Aseev, Sudar Nikolay T.
1
The paper deals with research of glasses based on heavy metal oxides Bi2O3 and PbO. We consider the application possibility of glasses mentioned above for the upconversion temperature sensors based on the ratio measurement of the luminescence peaks of Er3 + ions in the 500–700 nm region. The glass composition of 35Bi2O3-40PbO-25Ga2O3 (mol. %) was considered as the object of the study; glass samples doped with Er3 + ions and co-doped with Yb3 + and Nd3 +  ions were also synthesized. In order to obtain the upconversion luminescence spectra of doped glasses in the 500–700 nm spectral region, the synthesis was carried out in quartz glass crucibles in contrast to platinum crucibles usually used for the synthesis of this type of glasses. The quartz crucible application enabled extension of the operational spectral range of glasses in the visible region. Absorption spectra in the visible and infrared bands were measured, and the OH group content in the glass was estimated on the basis of the absorption coefficient in the region around 3 μm. The obtained value of the absorption coefficient is substantially smaller than for a number of oxide multicomponent glasses. The luminescence spectra were recorded at excitation by a titanium-sapphire laser with 975 nm wavelength. We proposed a mechanism for description of the nature of the luminescence peaks with maxima about 531, 552 and 665 nm. A band intensity increase in the red spectral region relative to bands with maxima about 531, 552 nm was observed for a glass sample containing Er3+ and Yb3+ ions that was explained by the energy transfer from Yb3+ ions to Er3+ ions. The results obtained demonstrate possibility in principle to use the investigated glass composition as a sensitive element for optical luminescent sensors when synthesizing in a quartz crucible.
9
 Subject of Research.The paper deals with description of optical system wave aberration by Zernike polynomials. We perform the search of suitable point distribution (real ray coordinates on optical system entrance pupil) for the least squares method approximation. Six possible types of distribution are considered. The conclusion on their advantages and disadvantages is drawn. Method. The method essence lies in various types of distribution research for real rays on entrance pupil that allow for necessary accuracy with minimum rays number. Main Results. We compare standard deviation between the reference wave front and result wave front after approximation by Zernike polynomials by the least squares method for several types of point distribution (real ray coordinates) on optical system entrance pupil. The best types of distribution with maximum convergence are determined. Practical Relevance. The discussed distribution of points can be useful for ray tracing calculation through optical system for the further wave front reconstruction by Zernike polynomials. The usage of optimal point distribution can reduce the number of rays necessary for wave front reconstruction that increases drastically calculation speed.
STUDY OF AMBER (SUCCINITE) OPTICAL PROPERTIES BY IR-SPECTROSCOPY METHOD Iana I. Verkhovskaia, Prokopenko Victor T., Sapunova Natalia P.
15
Subject of Research.We propose a solution for amber identification problem (succinite) as an example of natural polymeric material of organic origin. The solution is based on obtaining its infrared absorption spectra by infrared spectroscopy. The advanced method makes it possible to obtain both real and elemental compositions. In the conditions of growing demand for the use of such composite (complexly composed) materials on an industrial scale and the lack of existing methods for determination of their composition, the proposed method can become a new solution to the identification problem. Method. The basis of the proposed method for succinite study by infrared spectroscopy is transmission spectroscopy with the measurement of specular and diffuse reflection. We used the infrared Fourier spectrometer VERTEX 70 (BRUKER), the RockSolid ™ interferometer with the HYPERION 1000V microscope for the study. Amber samples from the Palmniken deposit, obtained in the city of Kaliningrad, Russian Federation, were used as the researched objects. Samples of various degrees of transparency and heat treatment were selected. Main Results. We have obtained and comparedthe data of infrared succinite spectra by the proposed infrared spectroscopy method. The distinctive characteristics are shown in the four main spectra groups: 1700–1735 cm–1, 1640 cm–1, 2800–3000 cm–1, 3400–3480 cm–1, regardless of material transparency characteristics. Five main links on the obtained IR spectra have been experimentally identified, which can be used as characteristic features for the identification and diagnosis of the succinite from the Palmniken deposit in terms of material composition. The influence of amber thermal processing on the differentiation of its structure, in particular, the restructuring of the C-O group makes it difficult to identify in heat-treated materials and requires further investigation of this phenomenon. Practical Relevance. The proposed method may be of interest in the field of the theory of knowledge of materials science, research related to identification processes, processing and manufacturing of products from amber. The carried out studies can find application at synthesis of high-molecular compounds, in issues connected with the development and distribution of various cases of application of organic nature materials, succinite, in particular.

AUTOMATIC CONTROL AND ROBOTICS

ALGORITHM FOR ADAPTIVE SENSORLESS CONTROL OF SYNCHRONOUS MOTORS Bazylev Dmitry N, Pyrkin Anton Alexandrovich, Bobtsov Alexey A.
24
 We present an algorithm for adaptive sensorless control of a synchronous motor with permanent magnets based on nonlinear observer of rotor position. The proposed algorithm is based on the vector control method, which uses position and velocity estimates for generation of control signals. The developed observer is an extension of recently proposed robust observer, which generates the estimate of rotor position using magnetic flux estimates. The key feature of this observer is that only two motor parameters should be known for position estimation – stator resistance and inductance. The results of the experiments performed in the work demonstrate the effectiveness of the sensorless control algorithm with the original observer in comparison with the modern industrial sensorless controller. In turn, the proposed sensorless control algorithm with a modified observer results in a higher accuracy of position estimation in comparison with the original version.
SMITH SCHEME APPLICATION IN THE SERVO SYSTEM WITH DELAY IN THE MAIN FEEDBACK Bystrov Sergey V., Vunder Nina A., Pavlov Andrey S., Sinetova Madina M., Ushakov Anatoly Vladimirovich
32
 Subject of Research.The subject of the study is the system situation that arises when a continuous plant is included in the system, the main feedback in which contains the link of pure delay. It is shown that for this system situation it is advisable to design a control device for continuous plant in the form of a consecutive compensator. It is found that if the consecutive compensator is included in the structure of the system according to the Smith scheme, then the transfer function of the input-output ratio of such system will not contain the transfer function of the pure delay link neither in the numerator, nor in the denominator, therefore the delay in the main feedback does not affect the system behavior. This property of the system with a consecutive compensator included in the Smith scheme enables the developer to use an algorithm of its synthesis created for plant control systems without delay. Method. The algorithmic basis is based on the use of the Mason method of non-tangential circuits for the transformation of signal structures and the procedure for the synthesis of a consecutive compensator, as a device for controlling continuous plants without delay. The method is based on the properties of typical polynomial models. Main Results. The developer of continuous systems with main feedback with delay obtains a simple algorithm for the synthesis of a consecutive compensator included in the Smith scheme, which completely excludes the effect of the pure delay link on the system behavior. Practical Relevance. The obtained results are of practical value for cases when a plant is included in the system with main feedback containing a pure delay. This is especially important for real technological processes. Practical application of the obtained results is illustrated by computer experiment.

MATERIAL SCIENCE AND NANOTECHNOLOGIES

RESEARCH OF BIODEGRADATION AND ANTIMICROBIAL PROPERTIES OF POLYVINYL CHLORIDE SHEETINGS WITH PECTIN AND STARCH ADDITIVES Vladimir S.Sibirtsev , Kseniya V. Volkova, Khaydarov Akramxodja Kh., Tran Thanh Tuan , Stroev Sergei A., Radin Mixail A.
43
 The paper describes a new methodof stability assessment of polymericmaterials to destruction caused by various factors (such as mechanical loads, moisture and microorganisms' vital activity). This method includes puncture resistance comparison of researched material samples, determined after nine-day incubation of these samples in liquid nutrient medium with test microorganisms and daily 40 vol.% substitution of this medium for a sterile one, as well as after incubation of similar samples in a sterile medium, and without incubation of these samples. The described methodwas used to study stability of a number of new polymericmaterials to various types of destruction. The materials were made on the basis of vinyl chloride polymer with addition of 0, 1, 5 and 10 mass.% of starch and pectin. The effect of the mentioned materials on the growth and metabolicactivity in liquid nutrientmedium ofEscherichia coliATCC 25922 was studied also (according to dynamics of intensity change of elastic optical dispersion and conductivity of the mentioned medium during the first ten hours of its incubationat the presence of tested objects and test microorganisms). As a result, it is shown that all researched materials are resistant to moisture action. At the same time, allused additives even in 1 mass.% quantity considerably reduced mechanical strength of researched materials compared with pure vinyl chloride polymer; as well as increased biodegradationof thesematerials(though in substantially smaller degree at small quantities of the additives). Moreover,the lattereffect was provided by the addition of starchto vinyl chloride polymerin considerably greater degree, than the addition of pectin.Besides, all used additives reduced the antimicrobialeffect of the polyvinyl chloride base of researched materials. The more starch or pectin was contained in researched material, the greater reduction occurred; at the identical quantity of them it occurred in the presence of starch to a greater extent, than in the presence of pectin.
FUNCTIONAL GROUPS IONIZATION EFFECT ON CONFORMATIONAL PROPERTIES OF DENDRITIC MOLECULAR BRUSHES Mikhailov Ivan V. , Darinskii Anatoly A. , Leermakers Franciscus Andrianus Maria
50
 Conformational properties of dendronized molecular brushes with ionized terminal groups in the dilute solution were studied by the Scheutjens-Fleer numerical self-consistent field method. Brushes with the same molecular mass and grafting density of dendrons but different generation number were compared. The ionic strength was varied within the conditions of the good (athermal) solvent. It was shown that the brush thickness increases with the ionic strength decrease as a result of the deformation of grafted dendrons. The induced persistence length, which characterizes the contribution of the grafted branches into the bending elasticity of the brush, behaves differently at large and small ionic strengths. At high salt concentration the brushes with more branched dendrons show smaller bending elasticity similar to their neutral analogs. At low ionic strengths the induced persistence length increases by an order and depends very weakly on the dendron architecture. 
58
 A number of polyurethane foam composites modified with fillers of different nature (hydrophilic modified fullerene soot, hydrophobic fullerene soot, alumina (III) oxide, chromium (III) oxide) were synthesized. The filler was introduced into the prepolymer, which was then mixed with the hardener, in the way that the polymerization and crosslinking took place in its presence. A «Shimadzu» rupture machine, a «Novotcontrol» dielectric spectrometer, a «Bruker» IR Fourier spectrometer were used for the study. The cells were analyzed with the use of «Micromed С-11» microscope. The physical properties of polyurethane foams depend heavily on the size of the bubbles and, as a consequence, on the apparent density. In turn, these parameters are determined by a large number of others: the distribution of bubbles in size, the thickness of the bubble walls, and anisotropy of the polyurethane foam internal structure. Statistical analysis of the microscopy of samples showed that the introduction of nanoparticles leads to increase in the average cell diameter, and, as a result, to thermal conductivity growth. In addition, the mechanical strength of all foams increases with the introduction of all types of nanoparticles, except for the case with chromium (III) oxide. This fact may be associated with the antiplasicizing action of the particles on the polymer matrix. FT-IR spectroscopy was used to analyze the effect mechanisms of the fillers. It showed that the effect of particles on the polyurethane properties is related to the formation of hydrogen bonds between the particles and the matrix that leads to a change in the ratio of rigid and mobile polyurethane domains. The use of dielectric spectroscopy made it possible to establish that the glass transition temperature of the polymer also increases together with the increase in the content of hard domains
INTERNAL STRUCTURE STUDY OF POLYURETHANE-POLYUREA BY NUCLEAR MAGNETIC RESONANCE METHOD Ostanin Stepan A., Zuev Vyacheslav Viktorovich, Mokeev Maxim V.
65
 We study the effect of chemical composition, solubility parameter of the segments and their length on the size of the domains, interphase thickness of the interfacial layer and the degree of phase separation in polyurethane-polyurea synthesized from oligomeric diisocyanate, cuamine M and polyols based on polyethylene oxide, polypropylene oxide and polybutadiene. The measurements were performed by a variety of techniques with specific pulse sequence such as proton spin-diffusion solid-state nuclear magnetic resonance spectroscopy, nuclear magnetic resonance spectroscopy with cross-polarization. The measurements were carried out on Bruker Avance II 500 operating at proton frequency equal to 500.13 MHz. It was found that the properties of segmented polyurethane-polyurea depend directly on the degree of phase separation between the hard segments and the mobile matrix. The study of the transverse relaxation time of the samples showed that the molecular mobility in polyurethane is represented by four components. Understanding of the polymer formation process, components distribution by volume, and knowledge about predisposition to form certain connections can be used for creation of polymeric materials with the required characteristics important for the industry

COMPUTER SCIENCE

72
 Subject of Research.Application of barcoding technologies in the tasks of facial biometrics is posed and discussed. We analyze the achievements and estimate the shortcomings of existing solutions and examples of barcode creation according to the face images and the features extracted by them. Method. The ways of the problem implementation are determined and new solutions are presented based on linear (Code 128) and two-dimensional (QR) bar codes, as well as their color variants. The composition and volume of data are considered being used in the facial biometry and related applications: medicine, criminalistics and forensic-medical examination. Among these data there are face images, as well as sets of anthropometric points and additional information to them, information about the phenotype of FI and gender, and, finally, documentary information. Main Results. We have shownthe results of these data "recording and transferring" within the framework of various barcode layouts, as well as the results of their reading and ways of hiding from reading. The proposed color barcodes are defined as "BIO Code 128" and "BIO QR-code". While graphical display and computer memory record, they can be viewed as colored raster images that carry information about the face in each layer. At this, documentary information can be read directly from such color images by standard barcode scanners, and the rest of the information (face image itself, its anthropometric, accompanying parameters) is read and restored after their decomposition into layers R, green and blue.Practical Relevance. The layout variants of the "BIO Code 128" and "BIO QR-code" barcodes and the programs for their generation (written in the MATLAB package environment) can be used in the further studies of the barcoding problem in the tasks of the facial biometrics and its applications.
MICROSERVICE ARHITECTURE APPLICATION IN THE DESIGN OF INDUSTRIAL EQUIPMENT WITH COMPUTER NUMERICAL CONTROL Afanasiev Maksim Ya , Fedosov Yury V , Krylova Anastasiya A., Shorokhov Sergey A.
87
 Subject of Research. The paper deals with the microservice approach to development of control system for modular computer numeric control machines. Its properties, advantages, and disadvantages are analyzed. A heterogeneous computer network is proposed as the basis of CNC machine where nodes communicate via message queues. We present a platform architecture description of the selective photopolymer laser curing developed by the microservice approach. Method. The microservice approach is a modern interpretation of the service-oriented approach. It allows for system creation from small loosely coupled modules that is essential for modular equipment. Moreover, it makes it possible to embed equipment into modern cyber-physical production systems because of interoperability. Main Results. An architecture of the selective photopolymer laser curing device was implemented. Message queue was chosen as the main communication protocol of the system. A distributed non-relational database was used as data storage. Practical Relevance. The proposed approach can be applied in the technological equipment development for unit and small-batch production. Moreover, the equipment built according to the approach is easily compatible with cyber-physical systems, which are actively being developed now. 
98
 We consider problematic issues of information security for cyber-physical systems. The analysis of the characteristics of autonomous objects has been carried out. The paper presents a model for the information security monitoring system based on the characteristics obtained as a result of the electromagnetic radiation analysis of the electronic components of the autonomous devices in cyber-physical systems. A typical scheme for the system state determination is shown. For reasons of the device features providing the infrastructure, information security state assessment is aimed at the analysis of the system normal functioning, rather than the search for signatures and characteristics of anomalies during various types of information attacks. An experiment is described providing statistical information on the operation of remote devices of cyber-physical systems where data accumulation for decision-making occurs by statistical information comparison. The experiment results on information impact on a typical system are presented. The proposed approach for the statistical data analysis of autonomous devices based on a naive Bayesian classifier can be used to determine the information security states. A special feature of our approach is the ability for quick adaptation and application of various mathematical apparatus, and machine learning methods to achieve given quality of probabilistic assessment of information security state. The implementation of this type of monitoring does not require the development of complex system applications. It allows for implementation of various system building architectures processing the autonomous object on-board or data transfer and state calculation on external computer nodes of monitoring and control systems.
ELECTRONIC DOCUMENT FLOW BETWEEN PROJECT, PRODUCTION AND OPERATING ENTERPRISES IN THE CONTEXT OF INDUSTRY 4.0 DIGITAL ECONOMY Guryanov Andrey V, Shukalov Anatoly V, Zakoldaev Danil A., Zharinov Igor Olegovich, Nechaev Vladimir A.
106
 Subject of Research.We propose organizational schemesforelectronic document flow of design, program and technological documentation for instrument-making items in the companies, which run according to the rules of Industry 3.0 and according to the digital design and production rules of Industry 4.0. The most important point in the item life cycle is the exploitation documentcirculation at the stage of «designing-manufacturing-exploitation». Method.We used organization methods of project and manufacturing works for the instrument-making items production within the conditions of pilot-scale and full-scale production based on the general theory of automation design. Main Results.It is shown that the effect of the most advanced industrial technology implementation in the electronic document flow can be achieved through the application of project and manufacturing company archives based on the technologies of the Internet of things and cloud-based computing as means of technical support. The most important research result is the development of some organizational schemes for interaction between manufacturer, designer and exploiter in the view of exploitation documentation for the instrument-making item usage. Practical Relevance.The results of this research can be implemented  for the creation of instrument-making (machine manufacturing) automation design algorithms for digital production, operating within the conditions of Industry 4.0 digital economy. The presented organizational schemes of the electronic exploitation document flow can be reasonably implemented for the practice of situational support in the exploitation of instrument-making items
ACCURACY INCREASE FOR STEGANALYSIS METHODS BY OPTIMIZATION OF WAVELET TRANSFORM PARAMETERS Sivachev Aleksey V., Prokhozhev Nikolai N, Mikhailichenko Olga V
113
 Subject of Research. We have performed the study for accuracy increase of steganalysis methods used for detection of information hidden in wavelet domain. Methods. The methods proposed by Gireesh Kumar, Hany Farid, Changxin Liu, Yun Q. Shi demonstrate low efficiency when detecting the fact of embedding into the discrete wavelet transform domain. The paper considers the reasons for this fact. The basis of these methods is application of statistical moments for LL, HL, LH, HH domains obtained by wavelet transformation and additional image parameters making up a support vector. Main Results. We have analyzed the reasons for low efficiency of modern steganalysis methods in tasks of embedding fact detection in LH and HL domains that represents about 65% and 70% of correctly qualified images, respectively. The analyzed methods of steganalysis use such parameters as statistical moments, which have a high degree of variability that makes it difficult to classify images uniquely. We propose the technique for steganalysis accuracy increase by evaluation and taking account of the parameters’ error used by steganalysis methods by means of the specialized wavelet. The proposed technique gives the possibility to increase classification accuracy of images by 2.5–7.0 %. Practical Relevance. The results of work are useful for specialists in the field of information security in tasks of detection and countermeasures for the hidden transmission channels. The obtained results can be useful for development of steganalysis systems.
AN ALGORITHM FOR SEARCH AUTOMATION OF LIGHTING SOURCES OPTIMAL ARRANGEMENT IN URBAN ENVIRONMENT Sender Arina V, Shiyan Artem V., Chirkina Aleksandra V., Chirkin Artem M, Mouromtsev Dmitry I.
122
 The paper presents research results on the optimal  lighting  arrangement using the potential of space and geometry in an urban environment. A local urban area such as a city block is selected as an object of research. In the process of the block geometry analysis the required number of light sources and their position with the given characteristics of the sources are calculated. The proposed algorithm is based on the concept of the isovist from the theory of spatial syntax and consists of two stages: visibility map creation and the optimal arrangement of lighting sources. The result of the algorithm operation is an illumination matrix with the optimal arrangement of light sources and a list of their coordinates. The presented algorithm can be used to estimate an urban light demand. The algorithm presented in the paper can be used for design of schematic urban lighting. In particular, it can be used in the early stages of design to assess the project’s potential.

ENGINEERING AND TECHNOLOGIES

COOLING SYSTEM BASED ON HEAT PIPE WITH DEVICE FOR HEAT ABSORPTION FROM POWERFUL SOURCES Alexander V. Sharkov, Vladimir A. Korablev, Victoria V. Gerasyutenko
133
 Subject of Research.We have presented a cooling system based on a heat pipe usage with the device of heat absorption from powerful sources, that is, the heat accumulator. Method.The operation principle of heat accumulator based on phase changes is that the thermal energy is consumed for melting of working substance, and is removed partly into the environment. The experimental setup was assembled for the research. The heat pipe studied in the experiment had flat flanges. The heat accumulator was installed between them. The stearic acid was used as the melting substance in the heat accumulator. Main Results. We have studied the characteristics of cooling system based on the heat pipe with the heat accumulator. We have got the heat resistance dependence of the heat pipe and heat-sink on input power. We have performed comparison of thetemperature dependence of the cooling object base from time, in conditions, when the heat pipe is equipped with a heat accumulator and without it. Based on the obtained results the time was determined necessary for the heat accumulator to provide thermal behavior of the heat generation object. Practical Relevance. The heat accumulator, used in the cooling system, has high heat of phase changes. Such heat accumulators are used to work in conditions of heat generation of device, which can be pulsed or periodic. The heat accumulator usage in cooling system will reduce the heat-sink dimensions, reduce the amplitude of temperature fluctuations of cooled object and thereby improve its reliability.
OPTIMIZATION OF DESIGN PARAMETERS FOR DEPTH ELECTROMAGNETIC SPEED SENSOR Avanesov Yuriy L. , Bukanova Ayna N., Voronov Alexander S., Evstifeev Michail I.
140
 Subject of Research.Design features of a deep water electromagnetic speed sensor are considered. The principle of its operation is described; a finite-element model is developed. The design solutions that improve the performance of the induction sensor are shown. The design parameters are optimized by the criterion of strength increase.  Method. The study was performed using the finite element method in the ANSYS Workbench software. The calculations were performed in the Static Structural module with account for the distributed load simulating external hydrostatic pressure. To determine the effect of mechanical stresses on the design parameters a parametric model is used. The parameters in this model are ranged within the prescribed limits. At calculations all materials are taken to be isotropic. Main Results.  Calculating results of induction sensor stress-strain state under the impact of external hydrostatic load were obtained by the method of finite element analysis. The effect of the sensor case material, its thickness and geometry, on the maximum stresses arising in the structure is studied. Recommendations on the choice of design parameters are given for increasing the strength of the induction sensor confirmed by computer simulation. Practical Relevance. The results obtained can be applied in modernization, design and construction of new electromagnetic speed sensors operating at high hydrostatic pressures.

MODELING AND SIMULATION

147
 The paper presents research results on effect of the orthotropic axe directions of orthotropic silicon on the stress-strain state of sensing micromechanical accelerometer element within the conditions of thermal agitations. We proposed a mathematical model of orthotropic thin plate for the case of disalignment of the coordinate axes and the material orthotropic direction of sensor sensitive element. We developed and verified software for studying the effect of misalignment of the coordinate axes and the orthotropic direction on the stress-strain state of the sensing element. The software is comparable with ANSYS software package with respect to accuracy of the simulation results. The developed software was used for computer simulation; the displacement field dependences of a uniformly heated sensing element on misalignment angle of coordinate axes and orthotropic direction were obtained. Computer simulation revealed the presence of direction misalignment of orthotropic axes and the coordinate axes, resulting in symmetry disruption in the plate deformation under uniform heating. As part of the study, we have shown a nonlinear character of the stress-strain state dependence of the temperature-perturbed sensor on the misalignment angle of orthotropic axe directions. It was demonstrated that the maximum deflection change for different misalignment angle values does not exceed 3.2% of the nominal value. However, under the conditions of external dynamic, thermal and mechanical exposures, the cumulative effect of the maximum deflection value change can have a significant impact on the characteristics of the micromechanical accelerometer. Therefore, it seems advisable to perform future research of the effect of misalignment of orthotropic axe directions on the parameters of the inertial information sensors.
153
 We have performed testing of the scheme with customizable dissipative properties as applied to problems for complicated gas flow structure with the evolution of interface instability.The scheme is implemented by the splitting into two phases. The first one uses the central differences of both deformation and gradient terms of the Euler equations with artificial viscosity TVD limiters. TVD type reconstructions for convective terms with flux limiters are used in the second phase. A two-order TVD Runge-Kutta algorithm is applied to march the solution in time. We address the issue of numerical resolution and efficiency of the proposed scheme in comparison with some high resolution schemes through numerical examples: the implosion problem, the explosion problem and the double Mach reflection problem. The scheme with customizable dissipative properties in terms of cost (cost of machine time) – quality (resolution) is at the level of modern high order schemes. For some numerical examples, the proposed scheme is superior. The scheme can be recommended for numerical studies of both complex shock wave and vortex flows with the evolution of interface instability.

BRIEF PAPERS

CONDUCTIVE CONCRETE COMPOSITION Denisyuk Igor Yu., Uspenskaya Maya Valerievna, Fokina Maria I, Logushkova Kristina Yu.
158
 This paper describes our study of conductive concrete, the conductivity of which is achieved through the introduction of a carbon fiber stabilized by an inorganic surfactant in a concentration of 0.12w.%. Research methods are: infrared spectroscopy, optical microscopy and conductivity measurement. Carbon fiber and its surface structure were investigated by infrared spectroscopy; based on the obtained results inorganic surface-active substance was selected. The electrical characteristics of the material were investigated. It is shown that the conductivity exhibits percolation-type behavior. There is an irreversible increase in electrical conductivity when a current of about 250 mA/cm2 and more is passed.Possible mechanisms of this phenomenon are discussed.
163
 The paper considers the problem of Chinese Open Relation Extraction represented in a form of subject-predicate-object. In contrary to well-known multi-phase methods including word segmentation, part-of-speech tagging, and syntactic analysis, we propose a role approach to detection of parts of sentences without preliminary word segmentation. The key idea is to use syntactic words, prepositions and postpositions as part of speech and member of sentence attributes. Coupled with a small dictionary, it is enough for facts extraction by a query. The experiments conducted on a real technical text show satisfactory results comparable to a traditional approach
PECULIARITIES OF DIFFRACTION GRATINGS APPLICATION ON CHOCOLATE SURFACE Toropova Alexandra P., Fokina Maria I, Pozdnyakova Svetlana A.
166
 The possibility of the rainbow hologram application on the chocolate surface is considered.We present experimental results ondiffractive microrelief application with different periods on the surface of various chocolate types, differing by the percentage of cocoa products.The diffraction efficiency and lifetime of the samples is analyzed.
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