bluuebunny/crossref_metadata_2025 huggingface dataset:
Tendências genolexicais em adjetivos neológicos no português de Moçambique
Authors: Nhatuve Diocleciano
Published: July 2022

O objetivo deste estudo é descrever as tendências dos falantes do português de Moçambique na construção de adjetivos neológicos, à luz das teorias de morfologia e de mudança linguística. Constitui objeto do estudo um setor genolexical particular que abrange os processos de derivação de adjetivos denominais e deverbais pelos sufixos -ic(o) e -nt(e). A base empírica é constituída por adjetivos neológicos disponíveis na plataforma do Observatório de Neologismos de Moçambique. A análise qualitativa dos dados revela que, no processo de derivação lexical, embora recorrendo, às vezes, a unidades morfológicas das línguas bantu, os adjetivos derivados por cada sufixo obedecem aos preceitos da morfologia do português, o que justifica a necessidade da sua legitimação através de instrumentos normalizadores do portugugues de Moçambique. As novas unidades lexicais beneficiam em grande medida o processo de nativização do português no contexto moçambicano.
PROTOTYPE OF THE CALCULATION DEVICE OF DYNAMIC COST OF THE BASIC PART OF ELECTRICITY
Authors: Boiko I.
Published: July 2022

In order to implement flexible dynamic billing, consumers need to be able to respond dynamically, which is determined by constantly monitoring the impact of feedback between the supplier and consumers of electricity on changes in the values ​​of load parameters. Smart sensor technologies allow a unified power supply system to supply electricity more efficiently through dynamic analysis of supply and demand. It is proposed to implement the task of tracking the electricity consumed by each user in order to comply with the conditions of macroeconomic equilibrium and dynamic optimization of the pricing mechanism for electricity using the concept of smart meters.

The aim of the study is to develop a system for flexible dynamic determination of the cost of the basic part of electricity for each generator in the local isolated SmartGrid. If the volume of generated energy deviates from a certain level set for a given time interval, a new calculation of the new tariff value per basic part of electricity must be performed every second. Each consumer is connected to a meter, which registers the change in the amount of electricity received in a dynamic mode. The meter contains a built-in microprocessor and is equipped with a radio module for registration and data exchange with a summarizing microcontroller, which performs the functions of calculating the total amount of electricity consumed. As well as part of the electricity supplied by a particular generator. To calculate the cost of basic part of electricity for each generator in the power system and the total cost of electricity generated every second by all generators, the using of a third microcontroller with built-in microprocessor and radio module is proposed. As a result, the simulation of the proposed device on the example of a system with one generator demonstrated its adequate operation in accordance with the theoretical provisions.
STUDY OF XENON POWER FLUCTUATIONS IN WWER-1000 REACTORS IN ONE-DIMENSIONAL AXIAL GEOMETRY
Authors: Khalimonchuk V.A. , Palamarchuk M.M.
Published: July 2022

The article uses the adiabatic modelling method for slow transient processes in nuclear reactors. The essence of this method is that the spatial component of the neutron flux density is determined by the solution of static equations of neutron transport. And the time dependence is reduced to the change of parameters (neutron interaction cross-section) of neutron transport equations accordingly to the change of 135Xe, 149Sm concentrations.

In this work, we propose to use a unidimensional (axial) model in the two-group diffusion approximation to investigate xenon transients. As a result, the effect of delayed neutrons in this case may be overlooked. All neutrons are assumed to be instantaneous because the lifetime of both instantaneous and delayed neutrons is much shorter compared to the characteristic time of the xenon transition process. The diffusion equation is based on a balance equation in which the generation, absorption, and leakage of neutrons per unit core volume determine the rate of change in neutron density over time. The differential equations used to calculate the spatio-temporal behavior of the neutron field in the core volume are calculated numerically, by finite-difference method, and analytically. The neutron-physical constants of each axial layer are determined by averaging, taking into account the number and types of fuel assemblies in accordance with the loading of the core in question. The fuel assembly type constants are preliminarily calculated using spectral codes.

As a result of the work, an algorithm for the physical calculation of the WWER 1000 reactor in one-dimensional axial geometry was obtained, the validation of the developed program was carried out, a number of transient calculations were carried out and a variety of xenon transient optimizations were proposed.
OPTIMIZATION OF VOLTAGE CONVERTERS OF MATRIX AND INVERTER TYPES USING SIMULATION MODELLING
Authors: Grudska V.P. , Golubev V.V. , Denysenko O.S.
Published: July 2022

The paper presents the results of simulation modeling of functional capabilities of pulse converters of alternating voltage with free circulation of energy of two types: inverter type with intermediate link of pulsating voltage and matrix type with discharge of reactive load energy into the network. With the help of a software package OrCAD, the main modes of operation of these converters are investigated: lowering and increasing the output voltage relative to the input. The simulation results of each mode are presented in the form of diagrams of the control algorithm of the converter keys and diagrams of its electrical characteristics: input and output currents, voltage on the intermediate link (buffer capacitor) and output. On the basis of visual models for lowering and raising modes of work mathematical models and substitute electric schemes of the studied converters on intervals of their invariable structure are created. Simplified formulas for the approximate calculation of electrical parameters with sufficient accuracy for practice are proposed for both modes. Simulation models of the logic unit of the control system and the circuit of the power unit are presented separately for the three-phase matrix converter with energy reset and recovery. On the basis of visual models obtained with the help of the OrCAD software package, mathematical models and alternate electrical circuits of these converters at intervals of their constant structure were created. The conducted simulation allows to determine the most expedient areas of use of such converters and to perform optimization of their power circuits and control systems.
RESEARCH OF THE THERMAL REGIME OF THE BELT CONVEYOR MOTOR-DRUM
Authors: Pobigailo Vitaliy , Zaichenko Stefan , Zhukova Natalia , Shalenko Vadim
Published: July 2022

The paper presents a method for calculating the maximum power of the conveyor drive under the condition of the maximum heating temperature of the elements. To study the thermal regime of the drive, the drive was selected according to the motor-drum scheme. The peculiarity of this drive is the lack of fan and air cooling, which can lead to overheating. The main components that generate heat energy are an induction motor with a short-circuited rotor and a reducer. The space of the motor-drum is filled with working fluid, which performs the functions of lubrication and cooling of the system components. Analysis of the design of the motor-drum drive allowed to establish the quantitative characteristics of the sources of thermal radiation of the individual components of the drive, taking into account the peculiarities of the interaction of the components. Quantitative characteristics of the sources of thermal radiation of the individual components of the drive allowed to establish the mutual influences of different parts of the object of study on its temperature state. The heat balance equation is applied under the condition of uniform distribution of the heat field on the surface of the drive elements. The equation of thermal balance of the system motor-drum-environment allows to determine the limit values ​​of the drive power at known geometric parameters of the system. Coefficient of convective heat transfer coefficients between the working medium and the drum wall and the drum wall and the environment are used to determine the total heat transfer coefficient of the working medium-drum-environment system. Analysis of the obtained data shows a significant limitation of the required drive power. Limited drive power does not allow this type of drive to be used for long conveyors. Increasing the power of the drive according to this scheme can be provided by forcibly cooling the working fluid or changing the design of the drive by increasing the surface in contact with the working medium.
CORRECTION SCHEMES FOR THE GYROMAGNETIC COMPASS
Authors: Meleshko Vladyslav , Romanov Valery
Published: July 2022

In connection with the significant progress in the improvement of sensitive elements (gyroscopes, accelerometers, magnetometers), as well as the increased possibilities of information processing by computational means, it became necessary to use modern algorithms for constructing correction systems for the gyromagnetic compass.

The object of research is the correction circuits: with an adaptable proportional-integral-differential (PID) controller, with a Fuzzy controller, with a Kalman filter for correcting the gyroscopic meter according to the magnetic heading sensor. In this case, the well-known scheme of a gyromagnetic compass with a torque proportional-integral (PI) correction is taken as the basis for comparison. Smoothing of the oscillatory error of a magnetic compass, which may be predominant, is considered. The subject of research is the accuracy characteristics in the steady state.

The study is carried out by simulating the operation of a gyromagnetic compass. The root mean square error (rms) and the mean value of the error are taken as the correction characteristics. At the same time, the transitional process of the initial exhibition is also controlled.

In the algorithms under study, new solutions are applied.

In the differential PID channel, a quarter-period delay of the dominant oscillations is applied, and the gain of the differential channel is adjusted according to the oscillation frequency. This setting allows you to almost completely smooth out the oscillatory error of the gyromagnetic compass by compensating for the oscillatory error with the received signal in the differential circuit.

In the Kalman filter scheme, the resulting heading error estimate is in antiphase with the error. After the introduction of a delay in the estimate for half a period of fluctuations, the estimate almost completely corresponds to the error. As a result, the oscillatory error can be almost completely eliminated in the instrumental heading value.

The article shows that all three investigated correction schemes show better characteristics in comparison with the known basic scheme. The highest accuracy can be achieved when applying the Kalman filter with the necessary settings for the perturbation, observation and initial error matrices.

The simplest to implement is a circuit with an adaptable PID controller. Its characteristics are close to the scheme with the Kalman filter.
FREQUENCY METER WITH AUTOMATIC SELECTION MEASUREMENT RANGE
Authors: Tymchik Gregory , Podolian Oleksandr
Published: July 2022

Frequency meters with automatic selection of the measurement limit are used to measure the frequency of the input signal, which varies in a wide range. Signal frequency meters (frequency meters) are one of the most numerous groups of measuring instruments that are widely used in various fields of technology. There are a large number of frequency meters, which are based on different principles. At the same time, the issue of creating frequency change meters, which have a principle of operation different from well-known systems, is still relevant.

The aim of this work is to develop an electrical signal frequency meter with automatic selection of the measurement limit, based on a new principle of frequency measurement, which has not been used before. An approach to the construction of frequency meters with automatic selection of the measuring range is proposed. The measurement is performed using a low-frequency single-band frequency meter. Pulses traveling with the frequency of the input signal are pre-formed. Pulses are counted on the meter formed by series-connected decadal meters for a specified time, after which, using a logic circuit, sequentially analyzes the states of the meter outputs, starting from the output corresponding to the maximum distribution coefficient. The analysis is performed to determine the output of the divider, the frequency value of which is greater than the maximum corresponding to the penultimate digit of the single-band low-frequency frequency meter and does not exceed the maximum frequency corresponding to its last digit. After that, the input of the single-band low-frequency frequency meter is connected to the selected meter output and the frequency is changed with the indication of the number and the automatically selected range. An approach to the automatic measurement of the frequency of the input signal, which varies widely, is proposed.

The proposed method allows, using simple and affordable means of circuit construction, to make a frequency meter with automatic selection of the measurement limit. In the future, the proposed frequency meter can be used in measuring the frequency of the signal from non-destructive testing, which will expand the range of its technical means used in measuring the frequency of the signal from non-destructive testing.
ANALYSIS OF CIRCUIT SOLUTIONS FOR CHOOSING THE CONVERTER FOR A WALKING HEXAPOD ROBOT
Authors: Platov Ilya , Pavlovskyi Oleksii , Pavlovska Yuliia
Published: July 2022

In this paper, DC converters for their use in the power supply system of a walking robot - hexapod are considered. The problem of energy conversion of robots of this class is an urgent problem, because the quality of the transformation will depend on the time of their autonomous operation, which in turn is an important factor influencing the range of applications of the robot. In addition to power supplies, the converter plays an important role in this. The less losses it will provide during the operation of the robot, the longer the robot will be able to move in space and perform useful work.

In this regard, the analysis of existing circuit solutions was carried out - from the simplest versions of converters based on discrete components to more complex with the use of special chips. Based on the analysis, the advantages and disadvantages of certain types of converters were identified, directly for their use in the power supply system of a walking robot - hexapod.

Among the main types of converters were step-down, as their efficiency is higher than the step-up. In addition, the analysis of the types of transducers showed that linear transducers have worse efficiency compared to pulse. In this regard, the main emphasis in the work is on pulse converters.

Of the latter were selected converters built using special chips designed for use in converters, because compared to other circuit solutions, they allow not only to obtain stable current and voltage in wide ranges, but also have the ability to adjust them, making it easy to test on the model work different servos without replacing the converter. Due to the high values of the output current for the developed layout, you can do with one converter, which reduces the cost and simplifies the design as a whole. In addition, such solutions, compared to others, have less weight and size, which is positively indicated by the possibility of placing on the hexapod additional equipment or payload that the robot can carry in the process.
BASIC PRINCIPLES OF SPATIAL POSITION OF IMAGINARY AND REAL TONTOR STEP
Authors: Skytsiouk Volodymyr , Klotchko Tatiana
Published: July 2022

The article defines the relevance of modeling the parameters of spatial location of an abstract object when performing various functions. Thus, modeling makes it possible to determine object movement trajectories both during industrial application in technological processes and when used to create bionic objects, for example, the action of artificial limbs, correction of the movement trajectory of an object with spatial orientation defects.

The main goal of research was to substantiate the analytical models of object movement, taking into account spatial coordinate systems, according to which coordinate transformations are carried out during the functioning of an abstract object of various applications.

The creation of a sensory complex to compensate for violations of limb functions based on the justification of analytical models of vector field of main systems of the object, characteristic of its vital activity, can solve the possibility of real actions of an abstract biotechnical object in interaction with other objects of the external environment. It is necessary to compare the idealized parameters of vector fields with the real current characteristics of the object under study and to determine the difference as a differential function that corresponds to diagnostic parameters of state of object's limbs trajectory. Or when applied in industrial conditions, errors in the reproduction of the movement trajectory are taken into account.

As a result, the study of nature of this functional dependence of the state violation and its restoration in the automated mode of operation of the integrated tool will allow the creation of a computer-integrated hardware solution for the identification of objects that interact by approaching and touching their surfaces.

Thus, determining the positioning of TONTOR step in the space of movement of objects and during their interaction provides the possibility of the functioning of each abstract object when performing various types of work.

At the same time, it is necessary to significantly develop the base of physical and mathematical models that determine the vector fields of objects in dynamics over a certain time, taking into account the TONTOR step of the phantom and real spaces of the existence and operation of the object. Thus, hardware implementation of this hypothesis increases the accuracy of identification of objects interactions with a human limb, regardless of its condition, and the accuracy of determining their relative location in space.
A Tentative Correction to the Inappropriate Application of Mathematical Theory to Physics — and A Correction to the Assumptions underlying Probability Theory
Authors: Qin Sheng
Published: July 2022

For a long time, physicists always directly use mathematical tools to deal with physical problems, and few people pay attention to the difference between mathematical theory and physical theory. Just like the dilemma that physicists once faced when dealing with the problem of blackbody radiation function.By analyzing the difference between the theoretical basis of mathematics and the theoretical basis of physics, this paper draws the following conclusions: (1) The theoretical basis of mathematics and the theoretical basis of physics are different, so when we use mathematical tools for physics research, we need to be very careful. (2) Finiteness and discreteness should be the basis of the whole physical theory; This paper points out that it is not advisable to use infinite " " and infinitesimal "0" without restriction and demonstration in physics, as well as the continuity of functions, which will bring a lot of trouble to physical theory.At the same time, through the analysis of Banach-Tarski paradox and Bertrand paradox, this paper proposes that if we revise the basic assumptions of probability theory: assuming that "points" have quantized sizes, and "lines" also have quantized widths. After the correction, we can not only avoid the troubles caused by Bertrand paradox, but also make probability theory better for practical application.
Regulation of Pathological Blood Brain Barrier for Intracranial Enhanced Drug Delivery and Anti-glioblastoma Therapeutics
Authors: Wang Kai , Zhang Fengtian , Wen Changlong , Huang Zhihua , Zhang Yuwen , Hu Zhihao , Hu Fuqiang , Wen Lijuan
Published: July 2022

The blood brain barrier (BBB) is an essential component in regulating and maintaining the homeostatic microenvironment of the central nervous system (CNS). During the occurrence and development of glioblastoma (GBM), BBB is pathologically disrupted with markedly increased permeability. Due to the obstruction imposed by the BBB, strategies currently employed for GBM therapeutics still obtain a very low success rate and lead to systemic toxicity. Moreover, chemotherapy could promote pathological BBB functional restoration, accompanied with a prominent decrease of intracerebral therapeutics transportion during GBM multiple administration, resulting in chemotherapy failure for GBM treatment. The effective delivery of therapeutics into the brain still faces with severe challenges. Regulation of pathological BBB for enhanced transporting of therapeutics across the barrier may provide new opportunities for effective and safe treatment of GBM. This article reviews the structure and function of BBB in physiological state, the mechanisms underlying BBB pathological fenestration during the development of GBM, and the therapeutic strategies of GBM based on BBB intervention and therapeutic drugs transporting across the BBB.
Linking Remote Sensing with APSIM through Emulation and Bayesian Optimization to Improve Maize Yield Prediction in the U.S Midwest
Authors: Dokoohaki Hamze , Rai Teerath , Kivi Marissa , Lewis Philip , Gomez-Dans Jose , Yin Feng
Published: July 2022

The enormous increase in the volume of Earth Observations (EOs) has provided the scientific community with unprecedented temporal, spatial, and spectral information. However, this increase in the volume of EOs has not yet resulted in proportional progress with our ability to forecast agricultural systems.This study examines the applicability of EOs obtained from Sentinel2 and Landsat8 for constraining the APSIM-Maize model parameters. We leveraged leaf area index (LAI) retrieved from Sentinel2 and Landsat8 NDVI to constrain a series of APSIM-Maize model parameters in three different Bayesian multi-criteria optimization frameworks across 13 different sites across the U.S Midwest. A time variant sensitivity analysis was performed to identify the most influential parameters driving the LAI estimates in APSIM-Maize model. Then surrogate models were develop using random samples taken from the parameter space using Latin hypercube sampling to emulate APSIM’s behavior in simulating NDVI and LAI at all sites. Site-level, global and hierarchical Bayesian optimization models were then developed using the site-level emulators to simultaneously constrain all parameters and estimate the site to site variability in crop parameters. For within sample predictions, site-level optimization showed the largest predictive uncertainty around LAI and crop yield, whereas the global optimization showed the most constraint predictions for these variables. Lowest RMSE for within sample yield prediction was found for hierarchical optimization scheme (1423 Kg ha−1) while the largest RMSE was found for site-level (1494 Kg ha−1). In out-of-sample predictions within the spatio-temporal extent of the training sites, global optimization showed lower RMSE (1627 Kg ha−1) compared to the hierarchical approach (1822 Kg ha−1) across 90 independent sites in the U.S Midwest. On comparison between these two optimization schemes across another 242 independent sites outside the spatio-temporal extent of the training sites, global optimization also showed substantially lower RMSE (1554 Kg ha−1) as compared to the hierarchical approach (2532 Kg ha−1). Overall, EOs demonstrated their real use case for constraining process-based crop models and showed comparable results to model calibration exercises using only field measurements.
Параллельная реализация мультиоператорной схемы 16-го порядка: приложение к задачам неустойчивости вихрей и пограничных слоев
Authors: Липавский Михаил Витальевич , Lipavskii Mikhail Vital'evich , Толстых Андрей Игоревич , Tolstykh Andrey Igorevich , Широбоков Дмитрий Алексеевич , Shirobokov Dmitry Alekseevich
Published: July 2022

Рассматривается семейство схем для уравнений Эйлера и Навье-Стокса, основанное на мультиоператорных аппроксимациях производных с обращением двухточечных операторов и позволяющее обеспечивать очень высокие порядки. Описана общая идея MPI-параллелизации рассматриваемого типа алгоритмов, а также оценки параллельной эффективности. Представлены результаты прямого численного моделирования возникновения и развития неустойчивости двух типов -- неустойчивости вихря гауссовского типа в дозвуковом потоке и неустойчивость Толмина-Шлихтинга в дозвуковом пограничном слое. Общей чертой этих вычислений было отсутствие каких-либо искусственных возбуждений. «Возбудителями» неустойчивости оказались малые отличия численных решений от точных, широкополосные спектры которых могут указывать на некоторую аналогию с естественным турбулентным фоном в реальных течениях.
Особенности построения микросервисной системы для моделирования нестационарных состояний нелинейных схем
Authors: Гридин Владимир Николаевич , Gridin Vladimir Nikolaevich , Анисимов Владимир Иванович , Anisimov Vladimir Ivanovich , Васильев Сергей Алексеевич , Vasil'ev Sergei Alekseevich
Published: July 2022

Описаны основные проблемы настройки конфигурации зависимостей программных продуктов, построенных на основе микросервисной архитектуры. Приведены примеры описания конфигурации зависимостей ПО на основе системы семантического версионирования. Рассмотрена методика контроля зависимостей компонентов распределенных информационных систем. Описана методика построения математического обеспечения нестационарных состояний нелинейных электронных схем методами диакоптики. Отмечено, что необходимым условием возможности использования предлагаемой методики является отсутствие индуктивных связей между отдельными подсхемами, а также размещение внутри каждой подсхемы управляющих и управляемых переменных каждого зависимого источника. Показано, что практическая реализация предлагаемой методики позволяет значительно увеличить производительность схемотехнической САПР и повысить скорость решения задачи расчета, что особенно актуально при разработке распределенных систем автоматизации схемотехнического проектирования.
Model reference adaptive backstepping control of double star induction machine with extended Kalman sensorless control
Authors: Chaabane H. , Khodja D. E. , Chakroune S. , Hadji D.
Published: July 2022

Introduction. Newly, the design of a controller for speed control of double star induction motor as a research focus. Consequently, backstepping technique is used to recursively construct a stable control law for speed and flux. Nevertheless, this control law coming from backstepping requires the knowledge of speed and flux values; in practice the measurement sensors are expensive and fragile. The novelty of this work consists to propose a control strategy which based on accurate Kalman filter observer that estimates speed, flux and torque. This extended Kalman filter is an optimal state estimator and is usually applied to a dynamic system that involves a random noise environment. Purpose. Apply a backstepping control of double star induction motor based on principle of rotor flux orientation. This approach consists in finding a Lyapunov function that allows deducing a control law and a modified adaptation rule is referred and sufficient conditions for the stability of the command-observer, in contrast to other techniques who use nonlinear principle. Results. The simulation results are shown to illustrate the performance of the proposed scheme under parametric uncertainties by simulation on MATLAB. The obtained results showed the robustness of the sensorless control in front of load and parameters variation of double stator induction motor. The research directions of the model were determined for the subsequent implementation of results with simulation samples.
The method of multi objective synthesis of nonlinear robust control by multimass electromechanical systems
Authors: Kuznetsov B. I. , Nikitina T. B. , Bovdui I. V. , Voloshko O. V. , Kolomiets V. V. , Kobylianskyi B. B.
Published: July 2022

Aim. Development of the method of multi objective synthesis of nonlinear robust control by multimass electromechanical systems to satisfy various requirements for the operation of multi-mass systems in various modes. Methodology. The problem of multi objective synthesis of nonlinear robust control of multimass electromechanical systems is formulated and the possibility of satisfying various requirements for the operation of such systems in various modes based on the concept of functionally multiple membership of the state vector and the solution of the Hamilton-Jacobi-Isaacs equation is shown. A method for choosing weight matrices with the help the vector of purpose of nonlinear robust control is formed by solving a zero-sum vector antagonistic game has been substantiated and developed. Results. The results multi objective synthesis of nonlinear robust two-mass electromechanical servo systems in which differences requirements for the operation of such systems in various modes were satisfied are given. Based on the results of modeling and experimental studies it is established, that with the help of synthesized robust nonlinear controllers, it is possible to improve of quality indicators of two-mass electromechanical servo system in comparison with the system with standard regulators. Originality. For the first time the method of multi objective synthesis of nonlinear robust control by multimass electromechanical systems to satisfy various requirements for the operation of multimass systems in various modes is developed. Practical value. From the point of view of the practical implementation the possibility of solving the problem of multi objective synthesis of nonlinear robust control systems to satisfy various requirements for the operation of multimass electromechanical systems in various modes is shown.
Improvement of power quality in grid-connected hybrid system with power monitoring and control based on internet of things approach
Authors: Balakishan P. , Chidambaram I. A. , Manikandan M.
Published: July 2022

Purpose. This article proposes a new control monitoring grid connected hybrid system. The proposed system, improvement of power quality is achieved with internet of things power monitoring approach in solar photovoltaic grid system network. The novelty of the proposed work consists in presenting solar power monitoring and power control based internet of things algorithm, to generate DC voltage and maintain the constant voltage for grid connected hybrid system. Methods. The proposed algorithm which provides sophisticated and cost-effective solution for measuring the fault and as maximum power point tracking assures controlled output and supports the extraction of complete power from the photovoltaic panel. The objective of the work is to monitor and control the grid statistics for reliable and efficient delivery of power to a hybrid power generation system. Internet of things is regarded as a network comprising of electronic embedded devices, physical objects, network connections, and sensors enabling the sensing, analysis, and exchange of data. The proposed control technique strategy is validated using MATLAB/Simulink software and real time implementation to analysis the working performances. Results. The results obtained show that the power quality issue, the proposed system to overcome through monitoring of fault solar panel and improving of power quality. The obtained output from the hybrid system is fed to the grid through a 3ϕ voltage source inverter is more reliable and maintained power quality. The power obtained from the entire hybrid setup is measured by the sensor present in the internet of things-based module. In addition to that, the photovoltaic voltage is improved by a boost converter and optimum reliability is obtained with the adoption of the perturb & observe approach. The challenges in the integration of internet of things – smart grid must be overcome for the network to function efficiently. Originality. Compensation of power quality issues, grid stability and harmonic reduction in distribution network by using photovoltaic based internet of things approach is utilized along with sensor controller. Practical value. The work concerns a network comprising of electronic embedded devices, physical objects, network connections, and sensors enabling the sensing, analysis, and exchange of data. In this paper, internet of things sensors are installed in various stages of the smart grid in a hybrid photovoltaic –wind system. It tracks and manages network statistics for safe and efficient power delivery. The study is validated by the simulation results based on MATLAB/Simulink software and real time implementation.
Performance improvement of shunt active power filter based on indirect control with a new robust phase-locked loop
Authors: Chemidi A. , Benhabib M. C. , Bourouis M. A.
Published: July 2022

Introduction. Since the development of the first active power filter (APF) in 1976, many efforts have been focused on improving the performances of the APF control as the number of different nonlinear loads has continued to increase. These nonlinear loads have led to the generation of different types of current harmonics, which requires more advanced controls, including robustness, to get an admissible total harmonic distortion (THD) in the power system. Purpose. The purpose of this paper is to develop a robust phase-locked loop (PLL) based on particle swarm optimization-reference signal tracking (PSO-RST) controller for a three phase three wires shunt active power filter control. Methodology. A robust PLL based on PSO-RST controller insert into the indirect d-q control of a shunt active power filter was developed. Results. Simulation results performed under the MATLAB/SimPowerSystem environment show a higher filtering quality and a better robustness compared to the classical d-q controls. Originality. Conventional PLLs have difficulty determining the phase angle of the utility voltage sources when grid voltage is distorted. If this phase angle is incorrectly determined, this leads to a malfunction of the complete control of the active power filters. This implies a bad compensation of the current harmonics generated by the nonlinear loads. To solve this problem we propose a robust and simple PLL based on PSO-RST controller to eliminate the influence of the voltage harmonics. Practical value. The proposed solution can be used to improve the functioning of the shunt active power filter and to reduce the amount of memory implementation.
MATHEMATICAL APPARATUS FOR MODELING OF THE PROPAGATION THE MAGNETIC FIELD ELECTRIC MACHINES WITH A GIVEN ACCURACY
Authors: Levchenko Larysa , Glyva Valentyn , Burdeina Nataliia
Published: July 2022

. The problem of modeling the propagation local magnetic fields and spatially dispersed sources is large errors compared to field measurements. An important aspect of adequate modeling is the use of the correct mathematical apparatus. It is shown that in order to obtain reliable models of the propagation magnetic fields around electrical machines (generators, electric motors of different power, geometric dimensions and poles), it is advisable to apply the Gauss equation for a scalar potential. The solution of the equation in polar coordinates makes it possible to take into account not only the fundamental, but also other harmonics of the magnetic field (dipole, quadrupole, octupole). This allows, depending on the number of spatial harmonics taken into account, to obtain a model with the required accuracy (error) for predicting the magnetic field strength at any point around the machine.   It is considered in the paper that an electronic machine is an object of base radius R0. The presented approach makes it possible to unambiguously determine the location of zero field points at a distance from the source (for a quadrupole source and zero field lines, for an octupole source). The results of modeling and their verification by full-scale measurements for the most common four-pole machines (quadrupole source) are presented. The main task of modeling the propagation the magnetic field of such sources is to ensure the required accuracy based on the goals of modeling. It is shown that the modeling accuracy and the presence of zero field points are due to different field levels near the electrical machine housing for different harmonics. The dipole harmonic at the cabinet is 20% of its own harmonic. But it falls more slowly with distance. This necessitates taking into account a different number of harmonics depending on the value of the ratio R0/R, R is the distance to the point of determining the field strength from the source. Therefore, with the ratio R0/R=2/3, the eighth harmonic is essential. At R0/R=1/5, already the fourth spatial harmonic can be neglected. Such data allow you to choose a rational number of harmonics. This reduces the amount of calculations and simplifies the process of modeling the propagation of the magnetic field around the source.
MODELING THE PROCESS OF TWO-FACTOR AUTHENTICATION
Authors: Rezanov Bohdan , Kuchuk Heorhii
Published: July 2022

The relevance of research. Authentication is the process of confirming the authenticity of an object or subject of interaction in an information network by a presented identifier. Usually only one factor is used. However, most information security incidents occur due to the use of one factor. The easiest way to create an extra layer of security for accounts is to use two-factor authentication using 2FA programs. In this case, an additional step occurs, which increases the user authentication time and creates an additional load on the network. Thus, there is a need to create an additional layer of security for accounts in the “Active Directory” directory service without using an additional component on the target system and an additional step in the authentication process, thereby making the authentication process itself simpler and more responsive to the user. The purpose of the article is to develop a model of the two-factor authentication process, which will allow comparison of different approaches to its implementation. Research progress. The proposed model consists of three components: a system submodel, a threat submodel, and a security properties submodel. The analysis performed showed the advantages of using the PERT method for this problem. The simulation of the authentication process was carried out using a third-party service for checking the second factor (DUO) and the proposed method. The final PERT-diagrams are formed. A comparative analysis of these methods in terms of authentication speed was carried out. Conclusion. The developed model makes it possible to assess the quality of two-factor authentication by the selected parameter with a sufficient degree of accuracy. In particular, the proposed method showed more preferable results in terms of authentication speed compared to conventional methods.
ON THE STABILITY OF THE STABILIZED MOTION OF A CARRIER ROCKET WITH A LIQUID-PROPELLANT JET ENGINE AND AN ONBOARD DIGITAL COMPUTER IN THE STABILIZATION LOOP
Authors: Aleksandrov Eugene , Aleksandrova Tetiana , Kostianyk Iryna , Morgun Yaroslav
Published: July 2022

The problem of choosing the values of the variable parameters of the digital stabilizer of the cosmic stage of a carrier rocket with a liquid-propellant jet engine and an onboard digital computer in the stabilization loop, which ensures stable movement of the stage along the entire active section of the flight trajectory, is considered. The effect of the stabilizer quantization period on the stability region of a closed-loop stabilization system is considered. It is recommended to choose the intersection of stability regions corresponding to uniformly distributed moments of time along the active section of the stage flight trajectory as acceptable values for the variable parameters of the stabilizer of a non-stationary stabilization object.
DEVELOPMENT OF THE METHODS FOR CALCULATING THE MAIN INDICATORS OF HEAT ISLANDS IN URBAN AREAS
Authors: Bekirova Lala , Mammadova Esmira , Bunyatova Elvira
Published: July 2022

The article is dedicated to the methods developed to calculate the main parameters of “heat islands” that appear in densely built-up urban area. Although remote sensing imaging is ideally used to track and detect frequent land cover changes in urban and surrounding areas as a result of sustainable urbanization and to calculate key parameters of "heat islands" seen in densely populated urban areas, satellite imagery is digitally manually The transformation of a parametric image into a land cover map using existing methods of classification is a long process, and therefore methods are proposed to determine the main indicators of the impact of "heat islands" in urban areas. A modified building density index has been formulated, which is highly informative, involving: (a) the proposed index reaches an extremum when the known building density index BDI and NDVI are equalized, (b) when the specified maximum is reached, it is easy to calculate the LST indicator using the known regression dependences of BDI and NDVI from LST. The method has been developed to calculate the area of “heat islands” on the base of the equivalent radius calculation using the known dependence function of the building density on the distance to the center of the urban area. Our study shows that the distribution of buildings and the slope of the relief affect the surface temperature (LST), in addition, the ratios of different LSTs vary in cities of different sizes, and each city has a temperature difference in LSTs, so the urban heating island To reduce the impact, it is important to identify the characteristics of the thermal environment in cities of different sizes. Urban greening is increasingly valued by cities around the world as an effective measure to reduce the negative effects of the urban heating islands, with different numbers and types of landscape dimensions, different statistical methods used in different surveys, as well as metric scale dependence and contextual differences between cities and we can overcome these challenges by conducting comparative research on time and space using a consistent methodology.
DEVELOPMENT OF THE DOUBLE-CONTOUR PROTECTION CONCEPT IN SOCIO-CYBERPHYSICAL SYSTEMS
Authors: Pohasii Serhii , Milevskyi Stanislav , Tomashevsky Bogdan , Voropay Natalya
Published: July 2022

The rapid development of mobile Internet technologies LTE (Long-Term Evolution) not only predetermined the further development of cyber-physical systems, which are based on the synthesis of technologies of classical computer systems and LTE technologies, as well as integration with Internet-of-Things technologies. As a result, the emergence of sociocyberphysical systems predetermines further development based on this integration. The creation of mesh- and sensor networks also allows the development of smart technologies and systems based on their conglomeration. The development and creation of a quantum computer, on the one hand, will make it possible to make a technical breakthrough in computing resources, use artificial intelligence, and on the other hand, it can lead to “chaos” in ensuring the security of modern technologies and systems. So, based on the algorithms of Shor and Grover quantum cryptography, symmetric cryptosystems based on traditional cryptography algorithms, as well as asymmetric cryptosystems, including systems based on elliptic curve cryptography, can be broken. The paper proposes to use a new approach to building security systems based on the concept of internal and external security contours. At the same time, security contours of continuous business processes are considered. This approach provides an objective assessment of the current state of security of the socio-cyber system as a whole.
METHODS OF COMPENSATION OF MICROBOLOMETER MATRIСES SELF-HEATING IN THE PROCESSING OF THERMAL IMAGES
Authors: Zuev Andrey , Ivashko Andrey , Lunin Denis
Published: July 2022

The sources of noise and artifacts arising during thermal imaging and the methods for thermal images filtering, including methods specific for processing of images generated by infrared sensors, are considered. In particular, distortions caused by the process of microbolometrer matrices self-heating due to internal and external heating sources and the methods for compensating such distortions are studied. The purpose of the study is to create a mathematical model of a bolometric matrix self-heating based on heat transfer equations and to develop an algorithm for suppressing of distortions introduced into thermal images by self-heating. The exponential models describing the propagation of heat in the microbolometer matrix are proposed and it is shown that the coefficients of the models after logarithming can be determined by the least squares method. For real thermal images, the coefficients of the model are determined, and situations are considered when the base temperature of the object is known and when it is necessary to restore it, and modifications of the exponential model in the form of an exponent from a complete and incomplete square are proposed. Computer simulation of the proposed distortion compensation algorithm has been carried out, a set of thermal images before and after processing has been presented, and a quantitative estimation of the degree of noise suppression caused by heating of bolometric arrays has been obtained. Based on the results of the work, it was determined that the exponential model provides a sufficient degree of closeness of the experimental and theoretically predicted temperature data, and the degree of difference between the data and the model was estimated. Recommendations are developed for the application of the proposed methods at known and unknown base temperature of the matrix. Proposals have been developed for further improving the mathematical model, including the situation of temperature changes over time, and for improving the efficiency of self-heating noise suppression algorithms.