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Objectives. Since the end of the 20th century, liquid crystals have taken a leading position as a working material for the display industry. In particular, this is due to the advances in the control of surface orientation in thin layers of liquid crystals, which is necessary for setting the initial orientation of the layer structure in the absence of an electric field. The operation of most liquid crystal displays is based on electro-optical effects, arising from the changes in the initial orientation of the layers when the electric field is turned on, and the relaxation of the orientation structure under the action of surfaces after the electric field is turned off. In this regard, the high quality of surface orientation directly affects the technical characteristics of liquid crystal displays. The traditional technology of rubbing substrates, currently used in the display industry, has several disadvantages associated with the formation of a static charge on the substrates and surface contamination with microparticles. This review discusses an alternative photoalignment technology for liquid crystals on the surface, using materials sensitive to polarization of electromagnetic irradiation. Also, this review describes various applications of photosensitive azo dyes as photo-oriented materials. Results. The alternative photoalignment technology, which employs materials sensitive to electromagnetic polarization, allows to create the orientation of liquid crystals on the surface without mechanical impact and to control the surface anchoring force of a liquid crystal. This provides the benefits of using the photoalignment technology in the display industry and photonics—where the use of the rubbing technology is extremely difficult. The optical image rewriting mechanism is discussed, using electronic paper with photo-inert and photoaligned surfaces as an example. Further, different ways of using the photoalignment technology in liquid crystal photonics devices that control light beams are described. In particular, we consider switches, controllers and polarization rotators, optical attenuators, switchable diffraction gratings, polarization image analyzers, liquid crystal lenses, and ferroelectric liquid crystal displays with increased operation speed. Conclusions. The liquid crystal photoalignment and photopatterning technology is a promising tool for new display and photonics applications. It can be used for light polarization rotation; voltage controllable diffraction; fast switching of the liquid crystal refractive index; alignment of liquid crystals in super-thin photonic holes, curved and 3D surfaces; and many more applications.

Polychloroprene is widely used as a special-purpose rubber in such industries as automotive, construction, textile industry. Chloroprene rubber takes a significant share in the market of elastomers due to its properties. In recent years, a gradual increase in demand for chloroprene rubbers is expected. This trend is most clearly seen in regions with a developed automotive industry. World leaders in the production of chloroprene rubbers and latex demonstrate their interest in increasing production capacity. In Russia, chloroprene rubber is not produced, the demand is completely met by import. In this paper, the main industrial methods for the production of chloroprene monomer, based on various feedstocks: acetylene and butadiene-1,3, exist in the world practice. Advantages and disadvantages of each of the above methods for producing chloroprene monomer are given. Technical solutions for the improvement of the chloroprene-monomer preparation technology for the steps of chlorination of butadiene-1,3 and dehydrochlorination of 3,4-dichlorobutene-1 in a column apparatus are proposed. An improved process for the preparation of chloroprene rubber from butadiene-1,3 is described. The development of a modern technology for the production of chloroprene rubber based on domestic raw materials will make it possible to obtain a high-quality target product, which will lead to the exclusion of its imports.

Purification of crude unrefined sunflower oil along with the removal of primary oxidation products is an urgent task to remove the solid constituents formed during the processing of sunflower seeds. All of them irrespective of the chemical composition negatively affect the quality of the food product and, over time, saturate the oil with coagulants that affect its organoleptic and physico-mechanical characteristics. The problem of cleaning unrefined sunflower oil by filtration with the use of vibroacoustic action is considered. The calculation scheme of the process is given, and an experimental setup has been developed that makes it possible to vary the angle of inclination of the filter element. The research of sunflower oil filtration in the field of vibroacoustic impact is carried out. In the study, a decision was made to expand the energy effects to create a cumulative system in the liquid medium that improves the hydrodynamic situation at the scale of the oil purification plant. It is established that the process speed can be intensified by creating additional microflows that provide an active influence on the motion of liquid, gas and solid particles. The results are obtained, which testify to the effectiveness of the use of vibroacoustic effects during the filtration of sunflower oil.

During the last decades becoming more sharply there is a problem of chemical and environmental monitoring and industrial inspection the content of toxic elements in food raw materials and foodstuff. At the same time there is a need to develop rapid methods, informative, integral, reflecting not only the safety but also the ecological purity of food raw materials. The method of determination of content of toxic elements on activity of its own lipase of in situ (AОL-method) in seeds of oil-bearing crops, on the example of sunflower is offered. The system of mathematical assessment of analytical criteria of laboratory test used in clinical laboratory diagnostics was for this purpose adapted. Sunflower seeds in which established the maintenance of toxiferous elements served as an object of a research: Cd, Pb, As, Hg, by atomic absorption method on the KVANT-Z.ETA device. Further tests divided on clear, including high-quality and pollution-free, and polluted - naturally containing toxiferous elements and which are artificially contaminated. Definition of activity of a lipase of seeds was carried out by the standard titrimetric method. Decrease of the activity of enzyme was connected with the maintenance of toxiferous elements. Proceeding from the received results counted an analytical significance (sensitivity, specificity, and predictive value of descriptiveness the positive and negative results) of determination of level of maintenance of toxiferous elements in sunflower seeds by the AОL-method. The set values of analytical specificity of a method and predictive value of a positive take at the level of 77.3% and 71.4% respectively, do not allow to use the offered method for the quantitative analysis, however, analytical sensitivity at the level of 86.2% and the predictive value of the negative result at the level of 89.5%, allow to recommend the AOL-method for screening programs of chemical environmental monitoring and technological monitoring of a contamination of seeds of sunflower toxiferous elements.

The 21st century aviation and aerospace technologies have evolved and become more complex and technical. Turbofan jet engines as well as their cousins, the rocket engines (liquid/solid) have gone through several design upgrades and enhancements during the course of their design and exploitation. These technological upgrades have made engines very complex and expensive machines which need constant monitoring during their working phase. As the demand and use of such engines is growing steadily, both in the civilian and military sectors, it becomes necessary to monitor and predict the behavior of parametric data generated by these complex engines during their working phases. In this paper flight parameters such as Exhaust Gas Temperature (EGT), Engine Fan Speeds (N1 and N2), Fuel Flow (FF), Oil Temperature (OT), Oil Pressure (OP), Vibration and others where used to determine engine fault. All turbo fan engines go through several distinctly different working phases: Take-off phase, Cruise phase and Landing phase. Recording generated parametric data during these different phases leads to a massive amount of in-flight data and maintenance reports, which makes the task of designing and developing a fault diagnostic system highly challenging. It becomes imperative to use modern techniques in data analysis that can handle large volumes of generated data and provide clear visual results for determining the technical status of the engine under investigation/monitoring. These modern techniques should be able to give clear and objective assessment of the object under investigation. Cluster analysis methods based on Neural Networks such as c-means, k-means, self-organizing maps and DBSCAN algorithm have been used to build clusters. Differences in cluster groupings/patterns between healthy engine and engine with degraded performance are compared and used as the bases for defining faults. Fault diagnosis plays a crucial role in aircraft engine management. Timely and accurate detection of faults is the foundation on which maintenance turnaround times, operational costs and flight safety are based. The data used in this paper for analysis was obtained from flight data recorder during one flight cycle. The final decision on a fault is taken by an engineer.

In the operation schemes of optical electronic devices (OED), such as digital autocollimators, direction finders, Shack-Hartmann sensors, as well as astro-orientation systems, projection measuring systems, geometric calibration schemes for OED, the photo-detector acts not only as a receiving device, but also as a measuring device. The tasks facing the OED photo-detectors. The solution to the problem is the use of several photo-detectors installed on one electronic board. Since OED photo-detectors act, inter alia, as measuring devices, it is necessary to perform their geometric calibration. Geometric calibration involves the measurement of interior orientation parameters used in the processing of OED images. Geometric calibration makes it possible to eliminate errors in mutual exposure of photo-detectors on one electronic board installed in the focal plane, as well as distortions introduced by the OED lens, primarily by distortion. The correctness of the interior orientation parameter determination is influenced by the relative position of the collimator, with the help of which the geometric calibration is performed, and the calibrated OED itself, i. e. the external orientation elements. The task is to separate the interior orientation parameters and the elements of external orientation. This is achieved using the method of mathematical processing of measured data in the forward and inverted positions of the collimator. This method of geometric calibration allows to use it for geometric calibration of OED with a large number of photo-detectors. The paper presents the results of the geometric calibration of the interior orientation parameters when the collimator projects a test object onto three photo-detectors of the OED layout. The factors influencing on the accuracy of the geometric calibration of the interior orientation elements for OED are determined in the paper. The developed method for geometric calibration of the interior orientation parameters for multi-matrix OED provides high measurement accuracy – not more than 0.1''–0.2''.

Studies on the influence of applying various technologies for combustion knock reduction have been presented in the paper. Among others, investigation concerning the following: over-expanded cycle, variable valve timing, internal and exhaust gas recirculation, leaning the combustible mixture and cooling the in-cylinder charge were of the interest. The research works were focused on impact of these technologies on both knock intensity reduction, and engine performance and toxic emissions. Results presented in the paper were coming from experimental investigation based on in-cylinder combustion pressure data acquisition. Additionally, knock intensity calculation methods were discussed. They are based on incylinder combustion pressure pulsations. Combustion knock intensity expressed by the maximum peak of the incylinder pressure pulsations shows a strong negative correlation with both the EGR ratio and relative equivalence ratio – lambda. With respect to a catalytic converter installed on the exhaust pipe line, applying EGR appears as better solution for knock reduction then leaning the combustible mixture because the catalytic converter needs stoichiometric mixture for effective NO x reduction. Furthermore, application of the over-expanded cycle to the hydrogen or coke gas fueled IC engine significantly reduces intensity of potential knock by 50 % in comparison to Otto cycle for all loads. Additionally, over-expanded cycle contributes to increase in engine thermal efficiency. Summing up, all the presented measures and technologies can be successfully implemented into practice in stationary engines as well as in traction engines, both of them working on either natural gas or gaseous renewable fuels.

Introduction. Nowadays robotics is one of the most important directions of fundamental, technical, scientific and applied research. The main robotics’ challenges are to develop schemes for obtaining information about environment and the creation of artificial intelligence effective systems of the complex dynamic objects’ control in uncertainty conditions. Recently, robotics is going through the stage of rapid development, more and more covering the civilian and military spheres of human activity. The number of developed and implemented mobile unmanned robotic complexes of military and dual-use exceeds the number of robotic complexes in progress. The purpose of the research is to review the most promising samples of mobile unmanned robotic equipment used in various fields of human activity.Results. The paper reviewed the modern developments of mobile unmanned robotic complexes applied in the agricultural complex, industrial and civil construction, and in cargo transportation. The authors analyzed promising samples of Russian and foreign unmanned robotic technology. Moreover, the authors presented factors that increasingly depended on key spheres of human activities in the development and implementation of mobile robotic systems. Therefore, the paper demonstrated the list of major programs and concepts for the development of the Russian Federation in robotic sphere.Discussion and conclusions. As a result, the authors identify the basic elements of automated control systems, of navigation and autopilot system basing on mobile unmanned robotic complexes. The paper also reveals the concept of the foveal vision, which allows quickly and accurately detect pavement roughness and obstacles on the vehicle’s way.

Nowadays the interest in search of ways of improving the efficiency of small radar cross-section aerial objects detection and localization rises against the background of widespread use of light and unmanned aerial vehi-cles. As a result, researchers pay attention to radar systems (RS) with continuous linear frequency modulation (linear FM) signal. The use of such signals gives the measurable opportunity to reduce radar system peak-speech power and to cut the cost and weightsize parameters of the RS. The paper observes low-power ground based radar implementation prospects for purposes of detection and estimation of motion rates of small-sized aerial objects. The proposed algorithm of radar signals processing enables to simplify the detection of such tar-gets. The paper reveals the structure and defines the steps of the algorithm. The fundamental for the algorithm under consideration is the method of the range-Doppler image composition of the scanned area using digital signal processing. The paper presents the results of the algorithm operation in the low-power RS of C-band radar, obtained by processing of quadrotor echo-signals during the real experiment. The results show successful solvation of the applied problem of detection and tracking on the small-sized aerial object with the radar cross-section equal to less than 0.5 m2 and the spectrum of secondary radiation characterized by the expressed multimodality. The results of the experiment validate the application of the algorithm and demonstrate the possibility of the algorithm implementation in design of portable RS and automated target acquisition centers for detecting and tracking of the small-sized aerial targets (both, single as multi agent) with the information display on operator control panel.

The existing non-destructive testing system of structure concrete is actually orientated on the usage of longitudinal acoustical waves. This is due to simplicity of technical realization for measuring velocity (time) of acoustical pulse propagation in bulk concrete. But a reverse side of simple measuring procedure is a loss of additional information on concrete which is contained in the accepted acoustical signal. Therefore usage of an ultrasonic concrete testing method is limited by assessment of its strength. Joint usage of several wave types, so-called multi-wave testing, allows to refine metrology parameters of the ultrasonic method and to gain more information while determining physical and mechanical properties of concrete in laboratory and in situ conditions. The paper considers testing of elongated concrete elements and structures by an ultrasonic pulsing method on the basis of longitudinal subsurface and Rayleigh waves. It has been proposed to use methodology for time selection of wave components according to amplitude parameter and it has been applied for standard acoustical transformers with considerable reverberation time and not possessing spatial selectivity Basic principle of the proposed methodology is visual (according to oscillogram of the received signal) determination of characteristic time moments which are used for calculation of differential value of a propagation velocity in the Rayleigh wave impulse. The paper presents results pertaining to simulation of acoustical pulse propagation on the basis of 0.15 m and data of concrete ultrasonic in situ testing on measuring bases from 0.25 to 1.75 m. Advantage of large baseline for sonic test is a possibility for execution of a hundred percent inspection for surface of large-sized elements and structures, and so there is no need to make a selective inspection in some control areas as it is stipulated by provided by existing regulations. Responsivity of the Rayleigh wave parameters to near surface concrete defects permits quickly and efficiently to detect crack areas in a reinforced structure. Energy localization of a surface wave in a layer having width λ/2–λ provides a possibility to ignore reinforcement availability under appropriate selection of oscillation frequency. In addition to this, large measuring baseline makes it possible to lower effect of concrete structural inhomogeneity on statistical stability for pulse velocity assessment that ultimately reveals a possibility to register an appearance of concrete acoustical elasticity effect under in situ conditions.

The paper outlines the problems of energy supply and waste utilization of the forest industries. As a solution, it proposes to use gasification to utilize wood leftovers, which is followed by electric power generation from combustion of producer gas. The plant was expected to have a power of 150 kW. The proposed power technology plant comprises a line for pre-treatment of wood chips, a gas generator (gasifier) and a gas turbine unit. The paper justifies a need for preliminary preparation of wood waste, particularly chipping and drying. Various drying schemes have been analyzed. A line for pre-treatment of wood chips comprises a drum chipper, a receiving raw material wood container and a drum dryer using fume gases. A co-current gasifier is chosen because of the high content of tar in the original fuel. In the co-current gasifier, most of the tar, passing through the high temperature area, is burned. The paper offers high temperature dry cleaning of producer gas in the cyclone separator. Such a scheme of cleaning provides high efficiency of the plant and simplifies its design, but suspended particles still remain in the producer gas. When analyzing the schemes of power converters this is taken into account. A choice of the gas turbine as a power converter is justified. To reduce the erosion damage of the turbine blades there is a proposal to use an unconventional gas turbine scheme with air turbine and a combustion chamber located downstream of the turbine. In this plant the air rather than the combustion gas passes through the turbine. The air from turbine goes into the combustion chamber, the combustion gas passes through the air heater, where it transfers heat to the air. Such scheme allows reducing power costs for the fuel gas compression before the combustion chamber. Optimization of the gas turbine cycle is performed. The optimum compressor pressure ratio is 3,7. The plant efficiency for this pressure ratio is 25,7%. Calculation results of the main elements are reported. Thus, the power technology plant, which allows us to solve problems of energy supply and waste utilization of the forest industries, is proposed.

At present the theory and calculation of single-stage high-pulse transformer (PT) are well developed. Their characteristics are determined depending on the type and load parameters. However, the method of calculation of PT executed in cascade is not fully developed. The main advantage of the cascade scheme is the transfer of the insulation from the inside to the outside. Due to this electric field intensity can be reduced at the inner insulation number of times, the number of PT components in cascade. The paper presents the results of comparative experimental studies of the characteristics of single-stage and two-stage PT included in the resistive load and recharge mode capacitive storage through to PT exacerbates capacity. There are considered two types of PT with the same ratios, the number of turns of the windings and the section of magnetic cores, but different magnetic properties of the cores. The methodology of comparative research is to determine the forming properties of one- and two-stage PT schemes in the storage capacitor discharge on resistive and capacitive load across PT with following oscilloscope current and voltage at the load. Comparative studies have defined the scope of the cascade of PT schemes. The paper shows that the multi-stage schemes of PT are highly ineffective in the pulse shaping circuits on resistive load as the inductive elements of the equivalent circuits cascade PT form an inductive voltage divider. It has been shown that the cascade circuit is effective in PT overcharge mode sharpened on capacitive storage capacity in the matching mode, while the efficiency of such schemes is close to 100 %, and those positive properties possessed by the cascade circuits are realized.

In the present paper the modern approaches to the reasonable using of phytopharmaceuticals for diseases of gastrointestinal tract were discussed. Substantiates using groups of medicinal plants for the treatment of diseases of gastrointestinal tract based on important relationship «biologically active substance-pharmacological effect». According modern data of chemical composition and pharmacological activity in the attitude to this pathology the most important species of medicinal plants are considered. The importance of principle of phytotherapy’s safety as a main approach of evidential medicine was highlighted. This scientific paper will help experts to make an evidence-based decision of medicinal plants and phytopreparations based on them in clinical practice.

The paper considers new methodologies pertaining to on-board diagnosis of wear-out rate for friction linings of a clutch driven disk and friction discs of a hydraulic press clutch of transmission gear boxes which are based on physical process that uses friction work as an integrated indicator. A new methodology in determination of life-span rate for engine oil has been developed in the paper. The paper presents block schematic diagrams for on-board monitoring of technical state for power units of wheeled and tracked vehicles. Usage of friction work as an integrated indicator for determination of wear-out rate for friction linings of clutch driven disk and friction discs of a haydraulic press clutch makes it possible timely at any operational period of wheeled and tracked vehicles to determine their residual operation life and forecast their replacement.While taking volume of the used fuel for determination of engine oil life-span rate it permits quickly and effectively at any operational period of wheeled and tracked vehicles to determine residual useful life of the engine oil and also forecast its replacement.

The paper gives data on the prevalence of osteoarthritis (OA) and the rate of comorbidities in this disease. It discusses problems of adequate and safe therapy in these patients. The basic provisions of the 2015 clinical guidelines for the rational use of nonsteroidal antiinflammatory drugs (NSAIDs), as well as assessment of risk factors for NSAID-related complications are presented. The place of symptomatic slow-acting drugs for OA (SYSАDOA) and a clash of opinions as to their efficacy among different national or international communities of specialists are discussed. The 2014 ESCEO International Committee guidelines for the management of OA patients, which confirm the necessity of prescribing SYSDOA as initial treatment, are presented. The properties and function of synovial fluid in health and OA are depicted. Clinical and experimental findings have shown that, by improving the lubricating properties of synovial fluid, exogenous hyaluronon has many anticatabolic and anabolic effects and affects pathogenetically significant factors in OA. The results of randomized clinical trials (RCTs) comparing hyaluronans of different molecular weight are given. There are data of RCTs on the clinical efficacy and structuremodifying activity of hylan G-F 20 and on its significant pain relief in OA patients. The paper demonstrates benefits in surviving the analgesic effect of hylan G-F 20 versus intraarticular administration of glucocorticoids.

Laser gas analysers are the most promising for the rapid quantitative analysis of gaseous air pollution. A laser gas analysis problem is that there are instable results in reconstruction of gas mixture components concentration under real noise in the recorded laser signal. This necessitates using the special processing algorithms. When reconstructing the quantitative composition of multi-component gas mixtures from the multispectral laser measurements are efficiently used methods such as Tikhonov regularization, quasi-solution search, and finding of Bayesian estimators. These methods enable using the single measurement results to determine the quantitative composition of gas mixtures under measurement noise. In remote sensing the stationary gas formations or in laboratory analysis of the previously selected (when the gas mixture is stationary) air samples the reconstruction procedures under measurement noise of gas concentrations in multicomponent mixtures can be much simpler. The paper considers a problem of multispectral laser analysis of stationary gas mixtures for which it is possible to conduct a series of measurements. With noise overshoots in the recorded laser signal (and, consequently, overshoots of gas concentrations determined by a single measurement) must be used stable (robust) estimation techniques for substantial reducing an impact of the overshoots on the estimate of required parameters. The paper proposes the Huber method to determine gas concentrations in multicomponent mixtures under signal overshoot. To estimate the value of Huber parameter and the efficiency of Huber's method to find the stable estimates of gas concentrations in multicomponent stationary mixtures from the laser measurements the mathematical modelling was conducted. Science & Education of the Bauman MSTU 108 The mathematical modelling results show that despite the considerable difference among the errors of the mixture gas components themselves a character of the error dependence on the Huber parameter for all gas components is the same. When an optimal Huber parameter (~ 0.00025 - 0.000025 in case of the specific mixture used in mathematical modelling) is selected the measurement errors of concentrations for all gas components are much smaller than the measurement errors when using the standard method of least squares

The paper considers an issue of updating a turbine blade finite element model. The turbine blade is fixed in the special rig and the unknown contact conditions strongly influences on the blade dynamics. Hence, there is a difference between the real blade dynamic characteristics and the results of the finite element simulation. The task is to update the blade FE model on the basis of the modal test data to obtain fine dynamic model of the structure. The experimental modal parameters are known with some scatter, which is the result of measurement errors, and some differences from blade to blade within the kit of parts.The proposed algorithm is capable to update the turbine blade finite element model by variation of elasticity modulus in contact areas taking into account the experimental modal parameters scatter. It is worth noting that elasticity modulus of finite elements near the contact area should be considered as unknown contact stiffness parameters.The stochastic updating algorithm based on the sensitivity analysis is proposed. The paper presents equations to define sensitivity coefficients and provides the special recurrence relations, on which the proposed algorithm is based. The eigenvalue problem is resolved repeatedly with system parameters changing during the algorithm implementation. The system parameters (elasticity modulus in the contact areas) are recalculated according to the recurrence relations, mentioned above. To implement the proposed algorithm, a special software in C++ language has been developed.The proposed algorithm has demonstrated its efficiency for updating the finite element model of the complex structure. Thus, the differences between the calculated eigenfrequencies and those of identified from modal testing have been reduced from 13% to 3%. The updated model of the turbine blade could be used for accurate simulation of the blade dynamic behavior under different operating conditions.

Before developing a central reducer of the drive intermediate axle, it is necessary to choose its kinematic scheme to define the most important truck properties. Examples prove that a type of gearing, kinematic scheme and mutual position of gear or worm wheels of the central reducer has impact on the mass of the intermediate axle, placement of the engine and brake mechanisms, and truck configuration as a whole. They also influence on a possibility to use a long-stroke suspension, provide a differential connection between axles, and a torque transfer to the next axle.The work analyzes various schemes of the intermediate central reducers using one or two pairs of gear or worm wheels. It defines the ways to provide normal operating conditions for the engine drive line of the non-intermediate axle. The paper shows that, in most cases, the two-shaft transfer cases with a coaxial or non-coaxial arrangement of the output shafts, connected in front of or behind a conical or hupoid reducer, allows implementation of intermediate reducers.According to a set of properties, for the trucks equipped with a dependent or independent long-stroke suspension, the most rational is the hub-reduction final drive with helical-bevel and conic central reducers, respectively, in intermediate and non-intermediate axles. To apply double helical-bevel central reducers in intermediate and non-intermediate axles is expedient if it is necessary to ensure unification of crankcase parts of axle, improve protection, and raise a driveshaft durability of the non-intermediate axle drive.The paper presents the most rational schemes for three drive axles to be group-driven. Creating a three-axis group-driven cart is possible to implement by setting one more axle in front of the two-axis cart, with central reducer of this axle having the same scheme, as a reducer in the intermediate axle of the two-axis cart. Thus, in case of differential connection between axles and identical vertical loads towards the axles in the central reducer of the first axle of the tridem drive axles it is necessary to use the asymmetrical inter-axial differential, unlike the central reducer of the second intermediate axle of the same cart where the symmetric inter-axial differential is set.

The paper considers an issue of object registration in the image through the generalized Hough transform with uncompensated geometric distortions being available. It proposes the method of geometric distortion correction and the method of parameter space normalization. The paper shows that the proposed algorithms require a relatively small amount of computations, but significantly improve the reliability of object detection. The paper may be of interest to professionals working in the field of pattern recognition as well as to graduate and undergraduate students attending lectures on the pattern recognition.

Войтович Николай Иванович, д-р техн. наук, профессор, заведующий кафедрой конструирования и производства радиоаппаратуры, Южно-Уральский государственный университет, г. Челябинск; voytovichni@mail.ru. Ершов Алексей Валентинович, канд. техн. наук, доцент кафедры конструирования и производства радиоаппаратуры, Южно-Уральский государственный университет, г. Челябинск; eav@list.ru. N.I. Voytovich, voytovichni@mail.ru, A.V. Ershov, eav@list.ru South Ural State University, Chelyabinsk, Russian Federation The dipole antenna providing 13 % bandwidth relative to the middle frequency with VSWR lower than 1.15 is presented. Based on the Lorentz's lemma the electrodynamic solution of the boundary problem is found in the paper. Also the principles of developing mathematical and numerical models of the antenna are discussed. The behavior of the rear and imaginary parts of the antenna input impedance and of the standing wave ratio (VSWR) in the feeder in the frequency range, as well as particular qualities of antenna pattern is presented in the paper. The good agreement between the experimental data and the calculated data obtained using a numerical model is shown. It is noted that the antenna is characterized by compactness, mechanical durability and low resistance to airflow. The antenna can be constructed as a tube or as a microstrip implementation.The possibility to provide the antenna matching with the feeder of the predefined impedance of 50 ohms, 75 ohms or another is discussed. Представлена оригинальная вибраторная антенна с КСВ ниже 1,15 в полосе частот, составляющей 13 % относительно средней частоты. В статье найдено на основе леммы Лоренца решение краевой электродинамической задачи, представлены принципы построения математической и численной моделей антенны. Приведены закономерности поведения активной и реактивной частей входного сопротивления антенны и коэффициента стоячей волны (КСВ) в фидере в диапазоне частот, особенности диаграммы направленности антенны. Показано хорошее совпадение экспериментальных данных с расчётными данными, полученными с использованием численной модели. Указано, что антенна характеризуется компактностью, механической прочностью, малым сопротивлением воздушному потоку. Антенна может быть выполнена как в трубчатом, так и в микрополосковом исполнении, при этом возможно обеспечение согласования антенны с фидером с заданным волновым сопротивлением: 50 Ом, 75 Ом или другим.

Integrated circuits, systems on a chip are the key links in various industrial systems and state defense systems. The emergence of counterfeit integrated circuits, problems of piracy, overproduction, unauthorized interference in the design of microcircuit, hardware Trojans require the development of methods and means of their timely detection. Trojans can be introduced into the integrated circuits structure both on the development stage and during the production process, including the stages of specification, design, verification and manufacturing. The inclusion of additional elements in the integrated circuits structure jeopardizes the functional suitability and reliability of the system as a whole. For the purpose of hardware protection of projects, the methods of hardware coding are currently used.The paper discusses the features and reliability of logical coding of combinational circuits. An algorithm for cracking the code of combinational circuits is proposed, based on the description of encoded structure by the resolution function and reducing the problem to SAT CNF. The initial data for decoding the structure of a digital device is the structural implementation of encoded circuit, obtained, for example, by reverse engineering (prototype design), as well as an activated physical sample of an integrated circuit, when into protected from unauthorized access memory the correct key value is loaded. This sample can be used as a black box model. The main idea of breaking a key is to solve a problem without research on a large interval of values of input and output variables.

Biomechanics of motor actions solves the problems of analysis of external motor events - kinematic and dynamic movement parameters. Inertial measurement devices such as gyroscope and accelerometer are used for biomechanical analysis of human movements. The paper describes an algorithm for analysis of kinematic characteristics of the running based on inertial gyro signals. Running is used to estimate the physical performance, endurance, coordination abilities of a person. Gyroscope signals were registered using the TrignoTM Wireless System. For data analysis in the MATLAB, the software for automated evaluation of electromyographic and biomechanical motion patterns was developed. The algorithm allows one to calculate time, spatial and spatial-to-time parameters of motion, symmetry of movements of the left and right limbs, and also stability of repetition of biomechanical movement pattern. The algorithm includes the following stages: 1) adaptive filtering of signals; 2) identification of movement phases; 3) calculation of spatial and time symmetry of left and right limbs; 4) analysis of the repetition stability of biomechanical movement pattern. The proposed algorithm was used to estimate the motor coordination potential of high-skilled athletes in longdistance running. The research made it possible to estimate individual features of work of each group of muscles for each sportsman while performing a test task with stepwisely increasing load on a running track. This approach is a tool to detect asymmetric work of paired muscle groups and of muscle groups with irrational workability. The proposed algorithm for the analysis of running kinematic characteristics can be used to develop new criteria for evaluating the effectiveness of solving a movement problem, as well as to assess the correctness of the movement technique and identify errors that can lead to injuries.

Light self-destruction-degradation of the second type has been observed in samples of semiconductor lasers with electronic energy pumping with high optical homogeneity and good quality of surface treatment. In these samples, damage appeared in the form of cords perpendicular to the ends of the resonator. According to the current understanding of the passage of powerful light streams through various media, the emergence of narrow light channels is due to the phenomenon of self-focusing. It refers to the fundamental physical mechanisms of propagation of laser radiation and is caused by nonlinear phenomena arising in a medium under the influence of high-power laser radiation. The physical reason for self-focusing is an increase in the refractive index n in a strong light field. Thermal self-focusing is the most probable cause of radiation redistribution in the active region of the crystal. However, it is possible that in the initial stage of the appearance of light channels a certain role is played by the growth of the intensity of radiation in certain sections of the crystal because of the instability of generation or small fluctuations in the pump current density. Then the process acquires an avalanche character, since the localization of the ray in the channel increases the density of light radiation which can lead to overheating of the substance and the activation of the thermal self-focusing mechanism. The experiments performed in this paper have shown that optically homogeneous crystals possess maximum resistance to degradation processes. In them, the critical power of light destruction is determined by the self-focusing threshold of radiation in a material. Since the nonlinear addition to the refractive index Δn = n2E2 at the self-focusing threshold is determined by the change in the concentration of non-equilibrium carriers ΔN(E2), the value of the maximum fluctuation DΔNmax itself is proportional to the value of the non-equilibrium carrier concentration at the generation threshold ΔNpores and the relative excess of the generation threshold J = (j – jn)/jn. Thus, a low threshold concentration of non-equilibrium carriers is one of the conditions for increasing material resistance to degradation processes. In doped crystals ΔNpores is less than in pure materials. This, perhaps, explains the rather higher value of Pcritial in the optimally doped homogeneous n-GaAs. Smaller values of Pcritial in p-type samples doped with zinc can be associated not only with the inhomogeneity of these crystals, but also with large generation thresholds. In addition, the cross section for absorption of radiation by holes is about 3–4 times larger than by electrons, which can also reduce the self-destruction threshold of lasers. At Т = 300 K, the lasing thresholds are higher that naturally reduces the value of the self-focusing threshold.

In this paper we presents the results of tests of automatic fire alarm systems in terms of reducing the temperature effect on building structures (floors), air ducts of the exhaust smoke ventilation system. Tests were carried out to determine the efficiency of the antismoke ventilation system for the removal of combustion products through steel air ducts with a metal thickness of 1 mm, as well as analysis of the temperature regime on building structures, the air duct of the exhaust smoke ventilation system under fire exposure. For the warning system (SO) of the second type, CO-2 we used on the basis of ISO “Bolid” devices. The launch of a fire warning system is provided for: automatically from an automatic fire extinguishing system; remotely from manual fire detectors installed at emergency exits from the vehicle storage room. Two full-scale firing tests were carried out for passenger cars. During the tests, the vehicles were ignited from inside the passenger compartment. In the course of the fire tests proved that the antismoke control ventilation ducts retained their integrity and tightness, which was confirmed by the positive protocols of aerodynamic tests of the smoke control ventilation system. The air ducts of the exhaust smoke ventilation system retained their integrity, the flange connections of the air ducts retained their strength and tightness, the fastenings of the air ducts were not damaged and retained their functions. The tests established the following: limitation of the fire center in the horizontal projection of the vehicle (the perimeter of the vehicle); filling the volume of the storage room for vehicles with a smoke-steam-air mixture occurs in an avalanche manner over the entire height of the room; as a result of the avalanche-like filling of the room, the absence of a neutral zone (security zone) was determined. Based on the results of the tests, it is possible to make changes to the existing technical normative legal acts.

A technological line for the production of granulated feed stuff was presented in the work. Three recipes for granular feed stuff for young rabbits (28-135 days old) were developed with the addition of experimental dietary supplements (PGC-92-1 supplements - dry herbal pulp from red clover, alfalfa grass flour and probiotic Sporothermin; PGC-92-2 supplements - protein feed concentrate from stillage filtrate (wheat), alfalfa grass flour and probiotic Sporothermin; PGC-92-3 supplements - green protein complex (PGC) from red clover, alfalfa grass flour and probiotic Sporothermin). Comparative analysis with the control recipe PGC-92 (control) without dietary supplements was carried out. The nutritional value of the feed stuff met the requirements for this group of animals. The storage of the produced feed stuff was carried out in production conditions (floor storage warehouse) in paper bags of 30 kg per group at a temperature of 18 ... 20 ° C and a relative humidity of 65 ... 70%. Due to the moisture content exceeding the requirements of the standard, a higher content of fungal and bacterial microflora was noticed in the feed stuff (control sample). The acid number of the fat and the total acidity increased, which indicates the instability of this batch of feed stuff during storage. Experimental variants of feed stuff had stable quality during storage and were of good quality throughout the test period. A production check of the influence of the studied complexes in young rabbits fattening was carried out in the conditions of the industrial complex of "Lipetsk Rabbit" LLC with a livestock of 2000 rabbits. The used complete granulated feed stuff with the introduction of bio-additives made it possible to increase the slaughter yield by 3.62, 4.45 and 3.96%, while reducing the feed cost per 1 kg of slaughter mass by 0.72, 0.38 and 0.88 ECU. An increase in profit was achieved by 17725.25, 16114.38 and 14168.55 rubles, as well as the level of profitability by 45.93, 41.26 and 31.24%, which is associated with a higher safety and productivity of the raised population of rabbits

Currently, due to the increase in the average speed of vehicles to ensure their visibility, the luminous intensity of their lightning equipment is constantly increasing, that can lead to blindness of other road users, especially at night. On the other hand, if you do not increase the luminous intensity if lanterns, a vehicle will not be noticeable in difficult road conditions (fog, rain, dust) and it can cause an accident. To eliminate this contradiction, a fundamentally new modular design of the adaptive rear combined vehicle light with non-replaceable light sources based on single powerful light emitting diodes and effective secondary optics of large diameter has been developed in the paper. The design provides for the use of an integrated microcontroller to control luminous intensity of its lights, depending on the conditions of external illumination, braking dynamics of a car and surface condition of a lamp diffuser with the possibility of transmitting data via a CAN-bus. Thanks to the built-in microcontroller, the developed flashlight is suitable for installation on vehicles without an on-board computer. These properties allow the flashlight to ensure visibility of a vehicle, and to avoid blinding the remaining road users. The design of the adaptive lamp is small in thickness (up to 40 mm), high luminous efficiency (at least 85 %) and reliability. The conducted lightning tests have shown that the developed lamp fully complies with UN Regulation No 6, 7, 23, 38, 48. The design has been compared with existing analogues of foreign production, which showed that such a lamp consumes less energy (30 %) and has a lower probability of failure due to the use of high-power LEDs used as a light source.

Catastrophic degradation takes place in case of reaching critical values of laser radiation density power in semiconductor lasers with electronically pumped energy made from single crystals of some compounds. It has been accompanied by mechanical destruction of the surface at resonator ends, an irreversible decrease in radiation power and an increase in generation threshold. Moreover, during the catastrophic degradation of semiconductor lasers under the action of intrinsic radiation, significant changes in the crystal structure occur within the single crystal: dislocation density reaches a value more 1012–1015 cm–2. It has been shown that initial density of dislocations and critical power density of the intrinsic radiation are inversely proportional. Thus, the degradation process of semiconductor lasers is directly related to generation and multiplication of dislocations during laser operation. Mechanical destruction of a crystal lattice occurs at critical values of laser radiation power and dislocation density. To clarify the proposed mechanism for the degradation of semiconductor lasers, it is necessary to take into account an effect of dislocations on optical properties of semiconductors. Typically, this effect is considered as follows: dislocations cause an appearance of a local deformation field and, in addition, form space-charge regions that surround a dislocation core in the form of a charged tube. The paper proposes a model of the phenomenon under study: large stresses arise in the dislocation core, leading to a displacement of individual atoms and deformation of the crystal lattice. Lattice deformation in the dislocation core leads to a local change in the width of a forbidden band. This change value is about 10–2 eV for a screw dislocation and 10–1 eV for a boundary dislocation. The mechanism of this change is that aforementioned deformation leads to a multiple rupture of electronic bonds and an increase in the electron concentration in the dislocation core to approximately value 1018 cm–3. The developed analytical model of the degradation mechanism allows to perform selection of a semiconductor and estimation of a laser operating mode under conditions of increased radiation power.

The paper presents the case of the right-sided inguinal inflammation of a lymph node as a result of invasion of Dirofilaria repens, the parasitic pathogen of subcutaneous dirofilariasis in animals of the canine family. The diagnosis was verified on the basis of the parallel application of morphological studies of cross sections of the nematode in histological samples and the molecular biological method polymerase chain reaction of scrapings of histological material. The localization of this helminth inside the cavities of the human body is extremely rare. Only isolated cases of atypical localization of D. repens are described: in the organs of the chest, cervical lymphatic node in the spermatic cord and epididymis, which led to pseudotumor formations that needed to be differentiated with neoplastic processes. This case is of great interest to experts of various fields (surgeons, oncologists, infectious disease specialists and pathologists), primarily in the differential diagnosis of malignant neoplasms of the lymphatic system.В статье описан случай развития правостороннего пахового гнойного лимфаденита, развившегося в результате инвазии Dirofilaria repens возбудителя подкожного дирофиляриоза животных семейства псовых. Диагноз верифицирован на основании параллельного применения морфологического исследования поперечных срезов нематоды в гистологических препаратах и молекулярно-биологического метода полимеразной цепной реакции соскобов гистологического материала. Локализация данного гельминта внутри полостей организма человека регистрируется крайне редко. Описаны лишь единичные случаи нетипичных локализаций D. repens: в органах грудной клетки, шейном лимфоузле, семенном канатике и эпидидимисе, приведшие к псевдоопухолевым образованиям, которые необходимо дифференцировать с неопластическими процессами. Данный случай представляет большой интерес для специалистов различных специальностей (хирургов, онкологов, инфекционистов и патологоанатомов), в первую очередь при дифференциальной диагностике злокачественных новообразований лимфатической системы.

The paper is dedicated to influence of the rapid thermal treatment of the gate dielectric at a temperature of ~1100 ° С on the electrical parameters of the programmable time device with a correction of 512PS8. As the analyzed parameters of the given integrated circuit, the authors have selected breakdown voltage, gate leakage current, charge value of the gate dielectric breakdown with its thermal field tests performed. The breakdown voltage of the p -channel of the test transistor was measured by applying the linear voltage sweep from 0 to -100 V with the step of -0,5 V with the grounded drain and source. The leakage current of the gate Ig leak was determined at the gate voltage of -20 V. For evaluation of the charge properties of the gate dielectric of devices the, the thermal field tests were performed. The quality and reliability of the gate dielectric the authors the breakdown charge control was carried out ( Q bd ). It is shown that the rapid thermal treatment of the gate dielectric at a temperature of ~1100 ° С during 7 s with its presence on the non-working side ensures the breakdown charge value of 2,040 C/cm 2 , and with its absence - 2,230 C/cm 2 , while during the standard process of creating the given integrated circuit this value constitutes 1,230 C/cm 2 . This means that the most efficient influence on the improvement of quality and reliability of the gate dielectric is ensured by its rapid thermal treatment when missing the silicon dioxide on the non-working side of the wafer. As compared with the standard process of their fabrication, carrying out such treatment allows 5,29 times reduction of the gate leakage current, 3,50 times reduction of the charge states and 1,07 times enhancement of the reliability of the p -channel transistor, and for the n -channel transistor the given values constitute 10,67, 3,50 and 1,81 times, respectively. It is established that the reliability improvement for the CMOS integrated circuits of time devices during the rapid thermal treatment of the gate dielectric is determined by a step-up of its breakdown charge owing to the more perfect microstructure of dielectric, resulting in the rebuild of the charge states both in the bulk and on the boundary with silicon.

The paper analyzes the parameters of silicon avalanche LEDs and their use for electron-optical signal transmission systems. The advantages of silicon avalanche LEDs are shown, among which high speed and compatibility with silicon technology should be highlighted. Experimental avalanche LEDs based on nanostructured silicon were fabricated and studied. The results of controlling the electroluminescence spectrum of avalanche LEDs due to the choice of production conditions to form nanostructured silicon are presented. It was found that the temperature of the substrate during the deposition of the surface nanocomposite aluminum + silicon film affected the size of the formed silicon nanoparticles determining the spectral characteristics of avalanche LEDs. This allows shifting the maximum of their emission spectrum to a shorter wavelength region of the visible range due to the forming of smaller silicon nanoparticles. The authors have developed an optical interconnection system consisting of avalanche LEDs based on nanostructured silicon and a microchannel silicon wafer used to transmit a light signal. The study of various operating modes of the developed optoelectronic system was performed and an increase in the efficiency of optocouple based on avalanche LEDs to 0.2% due to the pulsed operating mode was achieved. It is shown that the efficiency of the optocouple increases with LED current and it is the pulsed mode of its operation that is characterized by the maximum current, which is due to more efficient removal of Joule heat in the intervals between pulses, ensuring stable operation of the entire system. The results obtained open up new opportunities for the development of optical interconnections between silicon chips and silicon optoelectronics in general.

Introduction. Remote monitoring of layered underlying surfaces is an urgent task. To assess the performance of new algorithms for processing the radar signal reflected from the surfaces, full-scale tests are required. As their carrying out demands big expenses, simulation modeling is actual. There are many methods of estimating an electromagnetic field (EMF) scattered by the earth's surface. However, there are no proven methods and algorithms for engineering calculation of the reflected radio signal in the conditions of this problem.Aim. The aim is to develop and to verify a software model to simulate the reflected multilayer extended structure of the radio signal received on board the aircraft.Materials and methods. The core of the model was based on high-frequency electrodynamics' methods, which allowed rapid calculation for large areas of targets with any number of layers. Simulation was produced using the MATLAB software package. The developed simulation model represented the result in the form of the normalized radar cross-section (RCS) of the multilayer structure. Since the layered structure had rough boundaries, the model provided triangulation of the boundaries of the volume-distributed object. The resulting EMF was calculated using the superposition principle. Each partial EMF value on the facet was calculated taking into account the phase and the polarization of the locally incident EMF.Results. In the paper the comparison of simulation results with theoretical calculations for the normalized RCS of a two-layer structure (difference is less than 10 percent) was presented. Verification for the coefficient of variation of the envelope of the reflected radio signal from the depth of groundwater (critical error was 7 percent) was performed. RCS modeling of the absorbing layer with different degrees of roughness of the layer boundaries was carried out. The upper boundary roughness (for maximal height deviation 0.1 m) affected on specific EPR more than lower boundary. It manifested itself in decreasing of RCS down to 30 dB.Conclusion. The developed model is intended to reduce expenses for designing synthesis of subsurface imaging systems with comparison of scheme "model of device development – field tests – completion – etc". The model is designed to verify the new signal processing algorithms for subsurface radar.

The aimof the paper: to identify promising diagnostic and prognostic biomarkers of pathological processes development based on the red blood cell membrane morphology and nanostructure in patients with brain disorders in the Intensive Care Unit.Materials and methods. The study included 24 patients from the anesthesiology and resuscitation ward of the Federal Research and Clinical Center of Intensive Care Medicine and Rehabilitology. Blood was acquired from the patients for standard tests, and all further tests were performed in vitro. The images of red blood cells were obtained using the atomic force microscope «NTEGRA Рrima» (NT-MDT, Russia) in semi-contact mode.Results. Patients from the anesthesiology and intensive care ward with traumatic brain injury, ischemic and hemorrhagic stroke, cerebral edema, and post-hypoxic encephalopathy had different blood cell shapes and localized defects of different topology on the surface of erythrocyte membranes including defects of pallor, torus, and nanostructure.Conclusion. In this pilot study we have shown that several defects represent the trigger mechanisms for the development of a total membrane damage. Local topographic defects of nanostructures and abnormalities of erythrocyte morphology are irreversible. The number and quality of these abnormalities may eventually be used as a diagnostic and prognostic biomarker of pathological processes.

A review of robotic systems is presented. The paper analyzes applied hardware and software solutions and summarizes the most common block diagrams of control systems. The analysis of approaches to control systems scaling, the use of intelligent control, achieving fault tolerance, reducing the weight and size of control system elements belonging to various classes of robotic systems is carried out. The goal of the review is finding common approaches used in various areas of robotics to build on their basis a uniform methodology for designing scalable intelligent control systems for robots with a given level of fault tolerance on a unified component base. This part is dedicated to industrial robotics. The following conclusions are made: scaling in industrial robotics is achieved through the use of the modular control systems and unification of main components; multiple industrial robot interaction is organized using centralized global planning or the use of previously simulated control programs, eliminating possible collisions in working area; intellectual technologies in industrial robotics are used primarily at the strategic level of the control system which is usually non-real time, and in some cases even implemented as a remote cloud service; from the point of view of ensuring fault tolerance, the industrial robots developers are primarily focused on the early prediction of faults and the planned decommissioning of the robots, and are not on highly-avaliability in case of failures; industrial robotics does not impose serious requirements on the dimensions and weight of the control devices.

The paper presents the results of studies of the operation of the inverting DC–DC converter with charge pump and LDO, which are part of the combined bipolar secondary power supply LM27762, at the near to maximum input voltage of 5.5 V and an output voltage of –4.9 V. The ripple voltages were measured at various load currents from 10 to 250 mA at the positive pole of the flying capacitor, at the output of the charge pump system and at the output of the microcircuit. It was shown for the first time on the basis of the obtained information that at low load currents up to about 107 mA the charge pump system operates in the burst mode, and at currents greater than 109 mA – in the charge pump mode with a constant frequency. The results do not confirm the information in the documentation on the microcircuit that, at themaximum input voltage of 5.5 V, the charge pump can enter the PWM mode in hot conditions. When working in burst mode, the presence of LDO in the LM27762 chip reduces the ripples of the negative voltage at the output. However, they significantly exceed the values given in the documentation on the chip. During switching to the constant–frequency mode, the level of negative voltage ripples at the output of the microcircuit decreases sharply, but it increases with further increase of the load current and exceeds the values given in the documentation.

The popularity of home canning contributes to a sufficiently high incidence of botulism worldwide. The canned products containing botulinum toxin do not change neither color, taste, nor smell of contents of canned food. The criteria for the severity of the course of botulism are considered a violation of swallowing liquid food and symptoms of difficulty breathing. A distinctive feature of the paralytic syndrome in botulism is its symmetry and the absence of a violation of sensitivity. The criteria of the severity of the course of botulism is considered a violation of swallowing liquid food and the severity of acute respiratory failure. The paper presents the features of the therapy of the patients with botulism in the intensive care unit. Clinical examples illustrate the difficulties in recognizing botulism at the early stage of the disease, which are due to the polymorphism of the clinical picture of botulism and the similarity of symptoms with other diseases. Most commonly, patients with botulism are diagnosed with acute intestinal infection or the neurological pathology. Patients are not hospitalized in a timely manner, which can affect the outcome of the disease. The ability to recognize botulism at the prehospital stage is necessary for all doctors.

В работе представлены три итерационных алгоритма быстрого преобразования Фурье с прореживанием по времени, имеющие алгоритмическую сложность O (N·R·log2N), где R — частотное разрешение спектральной характеристики (отношение длины набора частот к длине N набора отсчетов исходного сигнала). Алгоритмы отличаются способами организации вычислений: некоторые используют обратную перестановку битов, другие — дополнительные массивы. Приведены подробные вычислительные графы, а также блок-схемы разработанных алгоритмов. Полученные результаты можно использовать для улучшения отечественной электроники и программного обеспечения, а также включать в учебный процесс при подготовке инженеров в области цифровой обработки сигналов., This paper presents three iterative algorithms for fast Fourier transform with decimation in time; these algorithms have the algorithmic complexity O (N·R·log2N), where R is the frequency resolution of the spectral characteristic (the ratio of the length of the frequency set to the length of the N set of samples of the source signal). The algorithms differ in the way they organize calculations: some use reverse bit permutation, while the others use additional arrays. Detailed computational graphs and flowcharts of the developed algorithms are provided. The results obtained can be used to improve domestic electronics and software as well as may be included in the training process for engineers in the field of digital signal processing., ВЫЧИСЛИТЕЛЬНЫЕ МЕТОДЫ И ПРОГРАММИРОВАНИЕ: НОВЫЕ ВЫЧИСЛИТЕЛЬНЫЕ ТЕХНОЛОГИИ, Выпуск 2 2021

Анализ прогнозов специалистов показывает, что рост потребления электроэнергии в мире до 2030 г. составит 2,4 %. На сегодняшний день вырабатываемая на тепловых электрических станциях энергия составляет 2/3 от общей вырабатываемой всеми источниками. Большинство этих ТЭС в качестве топлива используют уголь. Доля ТЭС, использующих это топливо, - 40 %. При сжигании угля происходит интенсивное выделение загрязняющих веществ, таких как NOx и SOx, основные последствия которого: ухудшение состояния здоровья человека, смог, кислотные дожди, парниковый эффект и пыление. Одним из новых инновационных решений экологических проблем угольной энергетики может стать сжигание биомассы (отходы лесопиления и лесного хозяйства). По оценкам специалистов объем запасов древесины в России превышает 82·109 м3 и составляет 25 % от мировых запасов. Отходы ее переработки составляют более 30·106 м3 в год. Интерес к использованию древесной биомассы также обуславливается постоянно возрастающими требованиями по экологичности объектов теплоэнергетики. Цель: экспериментальное установление зависимостей условий (минимальных температур) и характеристик (времен задержки) зажигания от вида древесной биомассы и её влагосодержания на примере четырех достаточно доступных и широко распространенных видов древесины (наиболее калорийной и поэтому перспективной для теплоэнергетики). Объект: сухая и насыщенная влагой древесина четырех видов (кедр, лиственница, сосна и осина). Экспериментальные исследования проведены для древесных частиц с относительной влажностью: 5, 30 и 45 %. Метод: экспериментальное определение с использованием высокоскоростной видеокамеры Photron FASTCAM СА4 временных характеристик процессов зажигания частиц древесины в условиях, соответствующих по интенсивности нагрева камерам сгорания паровых и водогрейных котлов; регистрация температуры среды с использованием хромель-алюмелевых термопар. Результаты. Приведены выполненные с целью обоснования ресурсуэффективности использования в теплоэнергетике древесной биомассы (как базового топлива паровых и водогрейных котлов) результаты экспериментальных исследований процессов зажигания сухих и влажных частиц четырех видов древесной биомассы в среде нагретого до высоких температур воздуха. Установлено существенное влияние вида древесины на условия и характеристики зажигания её одиночных частиц. Также установлено значительное влияние влажности на времена задержки зажигания частиц исследованных видов биомассы. Такие времена, соответствующие древесине в естественном состоянии, в 3-4 раза превышают во всем (достаточно широком) диапазоне изменения значимых для практики температур времена задержки зажигания сухих частиц древесины. Установленные в проведенных экспериментах закономерности иллюстрируют перспективность использования в теплоэнергетике древесной биомассы как основного топлива или компоненты древесно-угольной смеси. Analysis of experts' forecasts shows that the growth in global electricity consumption until 2030 will be 2,4 %. Today, the energy generated at thermal power plants is 2/3 of the total energy generated by all sources. For most thermal power plants, coal is the main fuel. The share of thermal power plants burning coal reaches 40 %. Burning coal leads to intense emissions of nitrogen oxides and sulfur, the main consequences of which are deterioration in human health, smog and acid rain. One of the new solutions to the environmental problems of the energy industry is the combustion of biomass (sawmill and forestry waste). According to experts, the volume of timber reserves in Russia exceeds 82·109 m3 and accounts for 25 % of the world reserves. Waste from its processing is more than 30·106 m3 per year. Environmental requirements for heat and power facilities are constantly growing. This determines the interest in biomass use. The main aim of the research is to determine experimentally the dependences of ignition delay times during high-temperature heating of woody biomass of different moisture content using the example of four fairly accessible and widespread wood species (the most highcalorie and, therefore, promising) for heat power engineering. Object: dry and moisture-saturated wood of four types (cedar, larch, pine and aspen). Experimental studies were carried out for wood particles with relative humidity: 5, 30 and 45 %. Methods: experimental determination of the ignition temporal characteristics of wood particles under conditions corresponding to the intensity of heating to the combustion chambers of steam and hot water boilers using a high-speed video camera Photron FASTCAM CA4; registration of medium temperature using chromel-alumel thermocouples. Results. The paper introduces the results of the experimental studies of ignition of dry and wet particles of four type of woody biomass in the environment of air heated to high temperatures in order to substantiate the resource efficiency of using woody biomass (as the base fuel of steam and hot water boilers). A significant effect of the wood type on the ignition conditions and characteristics of its single particles was established. A significant influence of humidity on the ignition delay times of particles of the studied types of biomass was established as well. Such times, corresponding to wood in its natural state, are 3-4 times higher in the entire (rather wide) range of change of temperatures significant for practice, the ignition delay times of dry wood particles. The regularities established in the conducted experiments illustrate the prospects of using woody biomass in heat power engineering as the main fuel or components of a charcoal mixture.

The article discusses approaches to the choice of antihypertensive drugs, which may be based on the adoption and implementation of new clinical guidelines for the management of patients with arterial hypertension. This paper provides data on the efficacy and safety of candesartan, an antihypertensive drug, which advantages were identified during a large number of randomized clinical trials. It discusses the recently published data on the effectiveness of more intensive regimens of antihypertensive therapy to reduce the risk of moderate cognitive impairment in patients with arterial hypertension. In this regard, the authors provide data of the previously completed studies, which showed the effect of candesartan on the rate of cognitive decline in patients with arterial hypertension in the elderly and senile age. The features of the pharmacological characteristics of candesaratan that can remotely explain its clinical efficacy are considered. The data of experimental studies of candesartan in animals, which contribute to the concept of the possible effects of candesartan, are presented.

The disadvantage of (RLI) radar images obtained with a single-channel radar station is the presence of speckle that leads to intensity flashes increasing the number of false alarms when detecting point targets. Therefore, the detection and target distinguishing by their reflective capability (using the energy characteristics of the signal) is not effective enough. In polarimetric radar stations the formation of each image element is carried out by the output signals of four receiving channels. Joint processing of these signals allows minimizing speckle without reducing the resolution capability. The paper presents the results of the computer simulation of the suppression methods of the image speckle obtained in the polarized radar stations with the synthesized antenna aperture. The first one uses the norm of the backscattering matrix as a parameter of the intensity of the reflected signal resolution from the i-th element. The incoherent addition of the intensities obtained by sequential overview of the space with several rays is carried out in the second one. Both of these methods can be applied together. The block diagram of such processing for one strip of range is given. The computer simulation of the three-rayed suppression method of the image speckle obtained in the radar stations with the synthesized antenna aperture is carried out. As a model of the reflecting surface a random diffraction grating formed by a set of independent reflectors located at the nodes of a regular rectangular grid with a step of 1 m is chosen. In this connection the image of the grating is formed as an incoherent sum of three images obtained at different angles. The results show that the speckle effect reduces even at angular changes of the order of degree units.

The routine method to control metal surface layer is Vickers hardness test method. The existing nondestructive testing methods are based on measuring induction density and other magnetic quantities in magnetizer core. This causes the method error and restricts the ability to determine the structure of the processed material. The paper provides theoretical and experimental investigation of the method for controlling the hardened axis layer parameters by analyzing characteristics of stray magnetic field of the axis magnetized local surface area before and after rouletting. A method is proposed for determining the hardened metal layer thickness of the rolling stock axis, based on measuring the parameters of the magnetized local area stray magnetic field before and after processing. To justify the proposed method, mathematical modeling of stray magnetic field of the axis local magnetized section is performed before and after processing. Inspection for the hardened metal layer is performed using magnetization of the axis local segment with electromagnet, followed by measuring the stray magnetic field strength. The maximum value of the horizontal magnetic force is determined, which is an informative parameter. A mathematical model is developed for the magnetized section magnetic field, the results of numerical and field experiments are presented. The discrepancy between the experimental data and the results of theoretical calculations is estimated. The method makes it possible to control the thickness of the hardened metal layer and the quality of the hardening of the rolling stock axis.

The article summarizes the international experience of using different types of anesthesia for the surgical treatment of carotid artery lesions. The anesthesiology support of surgery on the carotid basin includes general and combined anesthesia of various types. The regional anesthesia is a separate field in the carotid surgery. The paper presents the advantages and disadvantages of each anesthetic technique. The recent publications show the superiority of regional anesthesia in terms of its cost-effectiveness, less frequent use of temporary intraluminal shunt, the possibility to constant monitoring of patient’s neurological status throughout the operation, and lower incidence of neurologic and cardiac complications. Complications of the regional anesthesia and the methods of their correction are described in detail. There is still no consensus about the choice of the optimal type of anesthesia for carotid endarterectomy, hence further large-scale randomized trials are needed.

Radical changes in the composition, diversity and metabolic activity of gut microbiome in critically ill patients most probably affect adversely the outcome of treatment. Microbiota dysfunction may be a predictor and presumably the main cause of infectious complications and sepsis. Clinicists use objective scales for evaluation of patient condition severity including specific parameters of disorders of organs and systems; however, microbiota function is not considered specific and, hence, not evaluated. Technical capabilities of the recent decade have allowed characterizing the intestinal microbiota and that helped understanding the ongoing processes. The authors have analyzed data about the role of intestinal microbiota as a metabolic 'reactor' during critical states, possible complications related to misbalance of 'harmful' and 'beneficial' bacteria, and examined potential of a targeted therapy aimed directly at correction of intestinal microbiota. Search for papers was carried out using Scopus and Web of Science databases 2001 to 2018 years: (Gut Microbiota) AND (Critically ill OR Intensive care unit), key words taken for the search were: intestinal microbiota, metabolism, sepsis, antibiotics, critically ill patients, multiple organ failure. A number of questions in understanding of the interaction between gut microbiome and host remain open. It is necessary to take into account interference of microbial metabolism while assessing metabolome of patients with sepsis. Among low-molecular compounds found in blood of sepsis patients, special attention should be paid to molecules that can be classified as ‘common metabolites’ of humans and bacteria, for example, degradation products of aromatic compounds, which many-fold rise in blood of septic patients. It is necessary to take into consideration and experimentally model changes in the human internal environment, which occur during radical transformation of microbiome in critically ill patients. Such approach brings in new prospects for objective monitoring of diseases by evaluating metabolic profile at a particular moment of time based on integral indices reflecting the status of microbiome/metabolome system, which will supply new targets for therapeutic intervention in future.

CuInSe2 thin-film solar cells are promising materials for photovoltaic devices. One of the main tasks of researchers is to find ways to increase the solar cells efficiency. In this paper we propose an original structure of a thin-film solar cell based on a tandem connection of a photoelectric converter and a thermoelectric layer based on CuInSe2. The photoelectric converter consists of CuInSe2 and CdS layers. A 3D model of the proposed thin-film solar cell was implemented in the COMSOL Multiphysics environment with using the Heat Transfer module. The simulation was carried out taking into account the diurnal and seasonal variations of both the ambient temperature and the power density of the AM1.5 solar spectrum for the geographical coordinates of Minsk. The solar radiation power density of about 500 kW/m2 can be achieved by using concentrators. The temperature pattern and temperature gradients are calculated in each layer of the solar cell without and with the temperature stabilization of the substrate back side as well as without and with the thermal insulation of the substrate ends. Graphs of the temperature gradients of the thermoelectric layer and the temperature variations of the photoelectric converter of the solar cell are given. As a result of the simulation, it is shown how the uneven heating of both the surface of a thin-film solar cell and its layers occur under conditions of diurnal and seasonal variations of both the ambient temperature and the solar radiation power density. Under concentrated solar radiation exposure, the photoelectric converter surface can be heated up to 700 °C without temperature stabilization of the solar cell substrate. The operating temperature of the photoelectric converter was maintained at no more than 2.35 °C in January and at no more than 14.23 °C in July due to the temperature stabilization of the substrate back side of the proposed device. This made it possible to achieve an increase in the output power of the solar cell both by summing the photoand thermoelectric output voltages and by the concentration of solar radiation.

The paper considers large-panel constructive system of multi-storey buildings and its industrial basis creates conditions for intensive volume growth in house construction. Application of hollow-core panels are recommended as floor slabs that allows to increase a distance between bearing walls, to improve planning solutions, and also significantly to increase thermal and sound protection properties of floor discs (coatings). Keyed joints having the highest resistance to shearing forces are used to ensure joint action of the slabs with wall panels. A supporting unit of floor elements in the precast-monolithic constructive system ARKOS by means of concrete keys is considered as a prototype of the considered joint. In order to increase a bearing capacity and improve reliability of joints it is envisaged to reinforce keys with space frames. Improvement of joint units is possible to carry out with due account of total number of the factors influencing on strength. Poltava National Technical University named after Yuri Kondratyuk has developed a general methodology for assessment of bearing capacity in keyed joints which is based on the variational method in the theory of concrete plasticity and reflects specificity of stress-strain state of the failure zone. For experimental verification of this methodology investigations have been carried out with the purpose to test operation of keys when they are reinforced in mid-height and reinforcement is distributed in two tiers. The observed experimental fracture pattern in the specimens has confirmed kinematic schemes accepted for calculations and comparative analysis of experimental and theoretical values points to their closeness. Two-level reinforcement significantly improves plastic properties of concrete keys and excludes brittle failure. The proposed design of the joint unit for floor slabs with wall panels is characterized by the ratio of key dimensions and shape of reinforcing cages in the form of hollow cylinders which ensure higher strength and seismic resistance of a joint.

The review provides the analysis of 34 papers on polymerase chain reaction (PCR) as a method of the Epstein-Barr virus (EBV) DNA detection in biological material of patients with EBV-associated cancer diseases including Hodgkin’s lymphoma (HL). A comparative analysis of different methods of EBV DNA detection in biological material is presented. EBV is associated with HL in 20 to 100 % of cases depending on a geographic region and HIV status. EBV-associated HLs are characterized by latency type II. EBV is found in all the atypical cells and can be detected in blood of EBV-associated HL patients by means of the PCR method. The review includes the results of studies on EBV detection using the PCR method compared to in situ methods of hybridization and immunohistochemistry in various EBV-associated cancer diseases including HL. The obtained data indicate that PCR can be used for quantitative determination of EBV DNA in blood plasma of HL patients for therapeutic efficacy monitoring and prognosis assessment of disease and relapses. Quantitative determination of EBV DNA in blood plasma of HL patients using the real time PCR method is a promising technique. Its further practical application requires standardization of the method, larger trials, and comparison to positron emission tomography.

In this paper we analyze the possibility of using special methods and equipment of coherent photonics when working with multi-parameter information. Inverse two-phase coding and operational analysis of multi-parameter data can realize a number of probabilistic algorithms. The possibility and expediency of realization of not only the correlation algorithm underlying the holographic image recognition but also universal statistical algorithms using photonics methods is substantiated. A comparative analysis of photonic medical diagnostic systems running on a wide range of algorithms: search for precedent, correspondence diagnostics, deterministic diagnostics, Bayes algorithm. The results of experimental studies of medical diagnosis and the prediction of complex conditions is presented. Such an analysis is carried out by the means of vector-matrix multiplication using laser photonics methods. It is significant that with the widening of the range of probability algorithms, it is possible to preserve certain advantages of the holographic method: multidimensionality, efficiency, high information capacity and speed, visibility and flexibility of the result presentation. The methods described are of particular relevance in connection with the first photonic processors.

Magnetic mode for 3-phase transformer with symmetrical magnetic conductor of frame design has been investigated on schematic model. The scheme consists of three non-linear coils having star-connection without zero wire. Weberampere characteristics correspond to similar parameters of separate frames of a magnetic conductor. It has been accepted that a magnetic flow of every frame is closed on itself without passing into other frame of the magnetic conductor. Electromagnetic state of equivalent diagram has been described by a system of differential equations which were solved with the help of MathCad program. Investigations have resulted in calculation of functions for magnetic frame induction and magnetizing current and their harmonic compositions; dependence of actual amplitude for magnetic field induction on amplitude of the main harmonic induction has been determined in the paper. While executing experiments it has been revealed the following: induction amplitude of the main harmonic in the magnetic field within frames of the magnetic conductor is higher in comparison with the design induction value by 15.5 %; due to non-linearity of weber-ampere characteristics in frames and properties of 3-phase system harmonic components, which are multiple of three, are initiated in the functions of magnetic induction for separate frames; high-order harmonics of function for magnetic frame induction being imposed on the main harmonic decrease an actual amplitude of magnetic field induction practically up to the design induction value within the operational range of the actual amplitude and in this context coefficients of high-order harmonics change insignificantly; harmonic components, which are multiple of three, are absent in magnetizing currents.

Mechanoluminescent sensing elements convert mechanical stress into optical radiation. Advantages of such sensors are the ability to generate an optical signal, solid-state, simple structure, and resistance to electromagnetic interference. Mechanoluminescent sensor implementations can possess the concentrated and distributed sensitivity, thereby allowing us to detect the field of mechanical stresses distributed across the area and in volume. Most modern semiconductor photo-detectors can detect mechanoluminescent radiation, so there are no difficulties to provide its detection when designing the mechanoluminescent sensing devices. Mechanoluminescent substances have especial sensitivity to shock loads, and this effect can be used to create a fuse the structure of which includes a target contact type sensor with a photosensitive actuator. The paper briefly describes the theoretical basics of mechanoluminiscence: a light signal emerges from the interaction of crystalline phosphor luminescence centers with electrically charged dislocations, moving due to the deformation of the crystal. A mathematical model of the mechanoluminescent conversion is represented as a functional interaction between parameters of the mechanical shock excitation and the sensor light emission. Examples of computing the optical mechanoluminescent output signal depending on the duration and peak level of impulse load are given. It is shown that the luminous flux, generated by mechanoluminescent sensing element when there is an ammunition-target collision causes the current emerging in photo-detector (photodiode) that is sufficient for a typical actuator of the fuse train to operate. The potential possibility to create a contact target type sensor based on the light-sensitive mechanoluminescent sensor was proved by the calculation and simulation results.

Currently, a promising trend in remote sensing of environment is to monitor the vegetative cover: evaluate the productivity of agricultural crops; evaluate the moisture content of soils and the state of ecosystems; provide mapping the sites of bogging, desertification, drought, etc.; control the phases of vegetation of crops, etc.Development of monitoring systems for remote detection of vegetation sites being under unfavorable conditions (low or high temperature, excess or lack of water, soil salinity, disease, etc.) is of relevance. Optical methods are the most effective for this task. These methods are based on the physical features of reflection spectra in the visible and near infrared spectral range for vegetation under unfavorable conditions and vegetation under normal conditions.One of the options of optoelectronic equipment for monitoring vegetation condition is laser equipment that allows remote sensing of vegetation from the aircraft and mapping of vegetation sites with abnormal (inactive periods of vegetation) reflection spectra with a high degree of spatial resolution.The paper deals with development of a promising dual-spectrum method for laser remote sensing of vegetation. Using the experimentally measured reflection spectra of different vegetation types, mathematical modeling of probability for appropriate detection and false alarms to solve a problem of detecting the vegetation under unfavorable conditions (with abnormal reflection spectra) is performed based on the results of dual-spectrum measurements of the reflection coefficient.In mathematical modeling, the lidar system was supposed to provide sensing at wavelengths of 0.532 μm and 0.85 μm. The noise of the measurement was supposed to be normal with zero mean value and mean-square value of 1% -10%.It is shown that the method of laser sensing of vegetation condition based on the results of dual-spectrum measurement of the reflection coefficient at wavelengths of 0.532 μm and 0.85 μm makes it possible, even with a measurement error of 10%, to detect vegetation sites that are under unfavorable conditions, with the probability of appropriate detection close to 1 and the probability of false alarms close to 0.

To date the developed and newly created laser systems (radar, range finding, altimetry, etc.) use (to ensure eye safety) the infrared (> 1.4 μm) range. At the same time, an ultraviolet range is of interest too. The most promising here is a wavelength of 0.355 μm (third harmonic of a YAG laser: Nd), since the atmospheric ozone absorption is still low (in the spectral range of 0.25 - 0.38 μm ozone absorption is increased with decreasing wavelength).The paper presents an experimental study of the statistical characteristics of lidar signals at the eye-safe wavelength of 0.355μm. As the statistical characteristics, were used a mean value and a standard deviation of lidar signal.Aerosol inhomogeneity available in the atmosphere has impact on the statistical characteristics of the received signal. Thus, the analysis of these characteristics allows us to view that in the atmosphere there is aerosol inhomogeneity. The article shows that the standard deviation of the signal caused by inhomogeneity is much higher than the standard deviation caused by the shot noise of signal and background as well as by the noise of electronic circuit.The article gives examples of the field of a coefficient of variations. After filtration the field also permits viewing the available atmospheric inhomogeneity of the backscattered signal.