No. 3 (2022)

Designing nonlinear control systems is still difficult, so many researchers are trying to find
some useful ways and methods to solve this problem. As a result of such research, some methods
have been seen trying to design a good enough control system for nonlinear plants. But a disadvantage
of these methods is the complexity, so it created a need to compare some methods to determine
which one is the easiest method to design a control system for nonlinear plants. It was
found a way to compare two methods, which is comparing the regions of initial conditions of thesystems which are designed using these methods. Two analytical nonlinear control systems design
methods are compared on the example of the design control systems mobile robots. The algebraic
polynomial-matrix method uses a quasilinear model, and the feedback linearization method uses
particular feedback. Both considered methods give a bounded domain of equilibrium attraction,
therefore the obtained control systems can be operated only with bounded initial conditions. The
numerical example of designing the control systems for one object by these methods and the estimates
of the attraction areas of the system’s equilibriums in these systems are given in the paper.
As a result of this paper, it was found that using the algebraic polynomial-matrix method will get a
bigger section of initial conditions of the plant’s variable than the same section which is given by
the feedback linearization method.

The work is devoted to the analysis of mechanisms of formation of recommendations and
evaluation of the user's reaction to them in the interactive mode of work with the geoinformation
system. One of the important areas of application of recommender systems is the search and decision-
making in spatial situations. A peculiarity of this class of problems is the uncertainty of taskdefinition and ambiguity of decision evaluation. Users are often faced with problems that do not
have a clear formulation. To try to solve them, it is necessary not only to designate the direction of
solution search, but also to find an adequate sequence of tasks with clearly formulated input and
output data. Recommendations in such cases are designed in a dialogue with the user-analyst to
develop a strategy for finding solutions. In this paper we study a smart recommendation system
using the experience of dialog interaction. We propose a model of adaptation to the mental image
of the problem, which builds the user, taking into account the levels of situational awareness and
cognitive load. The peculiarity of the model is the use of visual cartographic objects, which are
indicators of the state of the mental image. A recommendation is represented by a set of objects
that are introduced into the field of cartographic analysis. This implicitly induces a certain semantic
direction of increasing situational awareness. A criterion of satisfaction with the recommendation
is suggested. A diagram of recommender system states, which describes the selection of context,
adequate to the problem being solved, is given. The context is understood as an information
object, capable of providing program functions and data for solving problems of a limited class.
A sequence of contexts in an analysis session is considered as a precedent of experience. Indicators
of trend, tendency and rhythm are proposed for possible chains of contexts. The degree of
semantic proximity of precedents to the current course of search for a solution is estimated by
these indicators. Their use will increase the speed of adaptation.

The palm print is a unique and very useful biometric. A lot of research has been done on this
topic over the past few decades. Various algorithms and systems have been developed and successfully
implemented. Since this method does not provide more advanced information for personality
recognition, multispectral or hyperspectral imaging and handprint recognition could be a
potential answer to these systems. Biometric technologies have been widely used in the security
industry for authentication and identification over the past few years. An improved recognition
system is required to improve accuracy and speed. This article reviews some modern handprint
databases and describes the methods used and their accuracy. Face, fingerprint, iris, palm print,
hands are physiological biometric data. Of all biometrics, physiological biometrics offers the most
benefits. The PolyU-IITD non-contact palm image database compiled with a handheld camera
includes residents of India and China. The database of IIT Touchless Palmprints is sourced from
Delhi India students and teachers and consists of complete hand images. The database of
hyperspectral fingerprints created by the Hong Kong Polytechnic University was collected in the Biometric Research Laboratory Department using Meadowlark liquid crystal filters. The Multispectral
Fingerprint Database, Hyperspectral Database was compiled by Chinese research teams
of scientists. The polyU fingerprint database was collected from 193 people and contains
386 palms. The Chinese Academy of Sciences has developed the CASIA handprint database with
its own handprint recognition device. The XJTU fingerprint database is collected using iPhone 6S,
HUAWEI mate8, LG G4, Samsung Galaxy Note5 and MI8 gadgets. A literature review of current
research in this area is also presented. The advantages of hyperspectral images compared to multispectral
images are noted, hyperspectral images of palm prints are very difficult to fake.

The paper is devoted to consideration of variants of solution to some problems of diffraction
for printed arrays with anisotropic inhomogeneities. The rotation of the plane of polarization is
realized by means of a twist-reflector. On the basis of computational and full-scale experiments it
was shown that twist reflectors based on microstrip reflective type antenna arrays (RAA) can be
quite broadband. The obvious advantage of such twist-reflectors is simplicity of the technology of
their manufacture, small thickness and weight. In addition, in twist-reflectors based on printed
RAA, it is possible to constructively realize the necessary phase distributions of the field on their
surfaces. Thus, it becomes possible to use such twist-reflectors to create phase-correcting twistreflectors.
It is shown that introduction of impedance loads in the construction of the re-radiating
elements of the printed RAA opens additional possibilities for controlling the field scattered by it.
Thus, twist reflectors with improved characteristics can be realized on the basis of microstrip-pin
RAA. The results of numerical studies based on the author algorithms and computational programs
are presented. Besides, spatial polarizing filters and a controllable twist-reflectors based
on microstrip RAA are considered. If microstrip elements of a twist-reflector contain controllable
loads, then qualitatively new type of the microwave device is formed. This device enables to control
polarization of the scattered field. Such devices can be named by polarizing modulators or
manipulators. By means of printed RAA with elements of complex topology the spatial polarizers,
which can transform electromagnetic waves with linear polarization in waves with rotating polarization
and, in particular, in waves with circular polarization, are realized.

The article presents an overview of software for preparing three-dimensional models
(3D models) of objects for various purposes for transfer to a 3D printer for printing. It is noted that
recently 3D printing is an integral part of the additive manufacturing process. Specifies that in order to
perform the 3D printing process, created or downloaded 3D models stored in STL files must be translated
into the printer control language. Such a language is called G-code, and the programs that make it
possible are called slicers. It is noted that the main function of the slicer is cutting the object model into
separate layers. The article discusses an overview of slicer programs from various manufacturers. For
each slicer, characteristics are given that reflect its functional content, focus on a certain category of
users, affordability, support for other software, and other characteristics. It is noted that two types of
slicers are known - universal and specialized. Specialized slicers are usually focused on one technology
or one model line of printers, while universal slicers are focused on a wide range of printers. It is indicated
that in recent years, manufacturers have begun to create software that combines the processes of
model development and its translation into G-code. It is noted that the 3D printing process requires the
preliminary setting of many parameter settings involved in the process of printing software and hardware.
The above review shows that almost all slicers, except for the core of the program that calculates
geometric shapes and converts the model to G-code, have six standard settings blocks: for slicer, model,
printer, material, additional services and cutting. The tuning parameters for each of the tuning blocks
are given. The slicer programs considered in the article are selected taking into account the orientation
towards different user groups, their modern functional content, popularity and availability on the Russian
market.

The article describes a device that transmits data and processes commands over the MQTT
protocol on the Internet. A small batch was made to assess the performance in real practice. The
software for the microcontroller is written in C using a real-time operating system (RTOS), which
allows you to streamline software development through pseudo-parallel code execution, task synchronization
mechanisms (semaphores, mutexes), and a queue mechanism. The paper presents an
example of an algorithm for the interaction of FreeRTOS tasks: the tasks of waiting for a command
from the server, the tasks of measuring temperature, the main thread that sends a message
to the server in response to the appearance of a line in the message queue. The core of the MQTT
client being developed is the STM32 microcontroller and the GSM/GPRS SIM800 module. A large
number of interfaces are displayed on the device, which allows you to connect a wide variety of
peripherals (temperature, humidity, pressure sensors, servos, etc.). The device is able to independently
restore the connection to the network in case of its interruption. The proprietary implementation
of the MQTT protocol version 3.1 QoS 0 is used in the software of the control microcontroller.
MQTT messages are transmitted as part of a TCP connection established by means of a GSM module. The control microcontroller communicates with the GSM module via AT commands.
The possibility of two-way real-time messaging is implemented, which allows using the developed
microprocessor system both in the mode of an autonomous control device and in the interactive
mode of executing commands received wirelessly and sending the execution statuses of these
commands. The main feature of the MQTT client is the ability to remotely update the microcontroller
software (OTA), implemented using an auxiliary microcontroller and a flash memory chip.
The developed MQTT client is intended to be used as the basis of microprocessor systems - clients
of the Internet of Things.

The article discusses a neurocomputer system for predicting the resource of a power cable
line (РCL) using neural network technologies. A hardware modular implementation of a
neurocomputer (NC) implemented on the basis of FPGA was selected. To solve the problem of
predicting thermal processes of РCL, it was decided to use a NeuroMatrix NM6404 digital
neurochip with a variable structure due to their high performance compared to power consumption,
a high degree of versatility. To predict the temperature conditions of the РCL, an artificial
neural network (INS) was developed to determine the current temperature regime for the currentcarrying
core of the РCL. The architecture of the INS for the implementation of the NC of the SCL
temperature prediction system has been selected, which allows for long-term prediction of РCL
temperatures in real time. The choice of the activation function of the INS neurons for the implementation
of the NC of the SCL temperature prediction system, which allows for a long-term forecast
of SCL temperatures without increasing the error with an increase in the forecast range. The
proposed neural network algorithm that predicts the characteristics of the electrical insulation of
the РCL, based on the sliding window method for predicting time series, was tested on a control
sample of experimental data not included in the sample for training the INS. Experimental studies
of the proposed adaptive forecasting method have been carried out, namely, an adaptive algorithm
has been developed and the prediction of thermal processes in the isolation of the SCL from the
load current has been performed. Analysis of the results showed that the longer the aging time, the
greater the temperature difference between the original and aged sample. When analyzing the
data obtained, it was determined that the maximum deviation of the data obtained from the INS
during the experiment from the data in the training sample was less than 3%, which is quite acceptable
for this study result. It is shown that the developed methods and algorithms are elements
of an integrated power grid management system, and the developed adaptive NC model makes it
possible to assess the current state of insulation and predict the remaining life of the РCL.

Tracking the location of a person in a big country, a big city, and even an area has long
been a reality. Thanks to satellites, it became possible to know exactly where a person is. However,
such technologies are more intended for positioning in open areas, and their signal is not able
to overcome large reinforced concrete structures, as well as walls and ceilings in a building.
This article proposes a solution to this problem, considers the system for controlling the movement
of people in the premises. Such a system not only determines the position where a person is located,
with an accuracy of half a meter, but also creates a database that displays the date, time and
place of a person’s discovery, as well as his identification, indicating who exactly was discovered.
The system described in this article is very easy to understand and has a low cost. It works with
the ESP32 microcontroller and is based on Bluetooth Low Energy wireless data transfer technology.
The ESP32 microcontroller acts as a signal scanner with the RSSI parameter. The received
data, namely RSSI and a unique identifier, which is aimed at determining the identity of a person,
are sent to the ThingSpeak server, where the distance to the source, which is the smartphone, is
calculated, determining its location and recording movement. This uses methods to improve accuracy,
such as the Fingerprint algorithm. In the entire room at the installation stage of the system,
"fingerprints" are collected within the controlled area, reference RSSI values are determined at
such control points, and it is on their basis that a person's location is determined. Also, this material
discusses the solution of the problem of identifying and controlling the approach of people to
a protected object and the organization of a system for collecting and storing statistics on visiting
a controlled object.

The paper considers the problems of strategic analysis and the choice of directions for the development
of innovative enterprises in the conditions of transition to the 6th technological order and industry
4.0. The main levels of analysis are determined. The objectives of the strategic analysis are outlined
based on the scale of the research being conducted. The analysis tasks are highlighted, the solution of
which will allow achieving the set goals. The complexity of solving global monitoring tasks, which are
caused by a large volume of heterogeneous and unstructured information, is shown. In these conditions,
thematic search and analytical processing of information cannot be performed without the use of automated information and analytical systems and the creation of search services based on artificial intelligence.
A general monitoring procedure is proposed. The main stages of monitoring technological trends
are defined, the tasks to be solved within a specific stage and the planned result are shown. Based on the
general monitoring procedure, the main priority functions that the developed services should have are
determined. As well as the problems of their development and structuring of the received information in
the form of information objects and clustering of documents. In contrast to the well-known global monitoring
systems, in which the search is based on indicators: an increase in the use of keywords, an increase
in the number of new authors, quoting works from related fields. Algorithms are proposed that
provide the definition of reference topics, assessment of ranking and relevance of information. The description
of the algorithms is given on the example of creating a summary information table, with the
help of which the interrelationships of documents of scientific and technological development in each
direction of monitoring and the search for specific documents in the database are formed. The construction
of search services based on the presented algorithms will ensure the allocation of reference topics
of documents, provide more reliable results of clustering of unstructured information and the formation
of scientific and technological trends in information and analytical complexes. To implement the algorithm,
it is proposed to use the Python programming language. The implementation of these algorithms
will improve the quality and efficiency of information retrieval in conditions of a large volume of unstructured
information.

Quantum error correction (QEC) is required in quantum computers to mitigate the impact of errors
on physical qubits. The goal is to optimize the neural network for high decoding performance while
maintaining a minimalistic hardware implementation. The errors associated with decoherence can be
reduced by adopting QEC schemes that encode multiple imperfect physical qubits into a logical quantum
state, similar to classical error correction. The relevance of these studies lies in the mathematical
and software modeling and implementation of corrective codes to correct several types of quantum
errors in the development and implementation of quantum algorithms for solving classes of problems of
a classical nature. The scientific novelty of this direction is expressed in the elimination of one of the
shortcomings of the quantum computing process. The development of the theory and principles for constructing
modeling systems that are resistant to external interference (dependence of data distortion on
noise, dependence of the error of a quantum computing process on the measure and purity of entanglement)
for modeling quantum computing is a dynamic area, as evidenced by a large number of existing
models reflecting certain quantum computational processes and phenomena (quantum teleportation,
parallelism, entanglement of quantum states) and scientific papers. Although quantum computing is not
yet ready to move from theory to practice, it is nevertheless possible to reasonably guess what form a
quantum computer might take, or, more importantly for programming language design, what interface it
would be possible to interact with such a quantum computer. It is natural to apply the lessons learned
from the programming of classical computing to quantum computing. The analysis of works in this area
showed that a new qualitative level has now been reached, which opens up promising opportunities for
the implementation of multi-qubit quantum computing. Prospects for implementation and development
are associated not only with technological capabilities, but also with the solution of issues of building
effective quantum systems for solving actual mathematical problems, cryptography problems and control
(optimization) problems.

The paper discusses methods of forming special models for the representation of various sets
of knowledge in various information systems. The work is devoted to the application of distributive
semantics in the identification of significant combinations in one subject area (PRO) within the
framework of the formalization of linguistic expert information (LEI). The paper applies an approach
to the formalization of LEI based on a set of analytical methods, where linear algebra is used as
models. This approach makes it possible to initialize the procedure for the automatic formation of
hierarchical architectures of LEI or dendrograms when identifying significant combinations of titles
of several collections of texts. The scientific novelty lies in the proposed analytical approach using
distributive semantics in identifying significant combinations of titles of several collections of texts,
which allows for the analysis and processing of linguistic expert information. A distinctive characteristic
of the proposed approach is the ability to formalize the ABM "Global Optimization Methods"
based on the synthesis of various already existing hierarchies of the ABM under consideration. The
paper aims to create conditions for the formalization of the LEI by applying distributive semantics
when identifying significant combinations of titles of several collections. The practical value of the
work lies in the development of a new approach to the formalization of LEI, taking into account distributive
semantics when identifying significant combinations of titles of several collections of texts.
The ontology in owl format "Methods of global optimization" in the program "Protege" is also built
in the work. The ontology is built on the basis of related data about. The ontology constructed in this
work complements the search structure within the framework of the considered PRO and can be
supplemented and developed in the future.

The article is devoted to solving the problem of computational and time resources distribution
in grid systems based on the adaptation of polynomial algorithms to quadratic types of user applications.
The relevance of demand distribution validity problem for the distributed computing paradigm
in the context of information redistribution and uncertainty. The article deals with the problems of
scheduling heterogeneous computing resources in solving complex professional and scientific problems
achieved at different points in time, based on identifying resources by significant manifestations
of commitment and probability. A comparative review of consumption has been carried out. The
statement of the problem to be solved in the chosen research area is formulated. The problem of
scheduling a grid system with a centralized multiarchitecture, which uses the task solution of a
group-site, is substantiated. The use of this architecture requires the development of heuristic algorithms
for the distribution of computing resources, taking into account the properties of application
arrays and assessing the schedule compliance. Eliminating the occurrence of scheduling errors requires
the development of a formal apparatus that will identify the prospects of the application, introduce
their typing and build heuristic algorithms with quality assessment, selected for certain types.
The development of such a formal apparatus is an urgent task. An equally important task within the
framework of this mechanism is the construction of resource parity models and interaction between
users and the computing system models. The authors proposed to solve the problem of scheduling
computing resources based on the development and study of polynomial scheduling algorithms for
arrays of hyperbolic applications. The main theoretical accuracy of this study is the creation of a
formal scheduling apparatus, including the definition of resource sugar, as a model of user applications,
based on the performance of an operation in the scheduling environment on a set of resource
muscles. The scientific novelty of the research lies in the development of a central-ring polynomial
algorithm for the distribution of computational time resources in grid systems, which involves an
automatic scheduling algorithm for computing systems, adaptation to quadratic types of user applications
and improves the efficiency of computational time resources distribution. To evaluate the
developed efficiency of the software application algorithm and the conducted computational experiment
with rapidly generated classes of computational resources. Obtained comparative results of the
proposed algorithm practical efficiency experimental studies for the distribution of computational
and time resources. The described studies have a high level of theoretical and practical significance
and are directly related to the solution of artificial intelligence classical problems.

The study of the sea depths in order to ensure safety, the effective use of underwater resources
is an urgent task. The first part of the article briefly considers the physical phenomena and
limitations that arise during the propagation of electromagnetic waves in the visible range in the
underwater environment. It is shown that underwater vision systems (as a class of specialized
technical vision systems - TVS) based on conventional CCD matrices face a number of fundamental
limitations in terms of improving the efficiency of functioning in natural water of low transparency.
In particular, the use of artificial light sources as part of underwater vision systems in turbid
water leads to the occurrence of backpropagation interference (BPR), which leads to spurious
illumination of the optical device matrix. As a promising direction in the development of underwater
vision systems, it is proposed to use methods for subtracting POR based on information about
the polarization of light. In the review part of the article, the latest achievements in this field are
considered. The main part of the article presents the methodology for studying the proposed method
for subtracting the POR based on a comparison of the results obtained by processing images
with known methods for estimating the Stokes vector parameters DoLP and AoLP, which allow
obtaining information about the degree of polarization and the prevailing polarization angles of
the scene, respectively. The experimentally obtained results of processing an underwater scene in
water of varying degrees of turbidity using the DoLP, AoLP algorithms and the proposed methods
for subtracting the POR are presented. Distinctive features are the use of four rather than two
polarization directions in calculations, as well as the original mathematical apparatus for processing
signals from the machine vision camera matrix.

The article studies the problem of motion planning in two-dimensional mapped environments.
The review and analysis of known planning algorithms based on Voronoi diagrams, probabilistic
road maps, rapidly growing random trees, Dijkstra algorithms, A*, D* and their modifications, artificial
potential fields and intelligent heuristics are carried out. Based on the analysis, it is concluded
that classical methods in dynamic environments require significant costs in terms of calculation time
and the amount of memory used. The conclusion is made about the relevance of the development of
algorithms that increase the efficiency of known planning methods. In this regard, this article is devoted
to the development of a modified algorithm of rapidly growing random trees and the study of its
effectiveness in comparison with known methods. The article presents a modified algorithm for rapidly
growing random trees, characterized in that when checking for a path to a new potential node of
the tree, the path to some area near the specified node is checked. This reduces the number of nodes
in the tree under construction. The developed algorithm is first compared with the traditional algorithm
of fast-growing random trees. The comparison is made by the trajectory calculation time, the
amount of memory required, the path length and the percentage of situations in which the trajectory
to the target point was successfully found. Next, the developed algorithm is compared with the planning
algorithms of other classes. The study uses representative samples of numerical experiments and
various environments that differ in the density of obstacles and the presence of mazes. A study of
planning algorithms using the results of experiments on a ground-based wheeled robot is also being
conducted. Based on the results of numerical and real experiments, conclusions are drawn about the
advantages and disadvantages of the developed algorithm of motion planning and the feasibility of its
application in various environments.

The paper considers the problem of detecting dynamic obstacles on the accumulated occupancy
map generated by the computer vision system of a mobile robot. The purpose of this research is to
improve the quality of the obstacle detection algorithm by adding a particle filter to find moving objects
from the map data. In the paper, the problem of correct accumulation of data in the occupancy
map and reducing the delay in updating the map cells in which the object moves is solved. The modification
of the particle filter presented in the paper is able to work correctly with dynamic obstacles
in a wide range of speeds; it is resistant to outliers caused by random generation of the initial particles
velocities, and is workable under real conditions in real time in an environment with a lot of
moving objects. A heuristic has been created that reduces the number of misclassifications in occluded
areas. It is shown that the algorithm for detecting dynamic objects in the map is invariant to the
type of sensors used in the vision system, and an implementation combined with an accumulated
occupancy map is described. The algorithm is implemented and tested on board an autonomous mobile
robot, as well as on an open dataset. The article also provides a comparison with other approaches
of dynamic obstacles detection, as well as calculated performance metrics for all analyzed
methods for computers based on the GPU Nvidia RTX 3070 and Jetson AGX Xavier. Promising directions
for further research to improve the presented algorithm are formulated.

Digital signal processing is widely used in modern technology, including robotics, medical
technology, etc. Thus, the controlled digital filters are used to eliminate the constant component of
the output signal at the output of an analog-to-digital converter. This also reduces the low-frequency
interference level spread out on the frequency axis to the left of the lower boundary of the signal
spectrum. In actual situations, signals are subjected to a variety of disruptions and noises; however,
applying a filter may suppress these noises and produce a clean signal. Controllability means the
explicit dependence of the filter coefficients on the cutoff frequency. A transient occurrence can arise
in a digital filter, which is indicated in the overshoot of the signal. A change in the cutoff frequency
during filtering operation could cause this transient event. In this report, a Butterworth LPF filter is
used to offer a compensation strategy for reducing this overshoot. A transient is an overshoot (drive)
in the result timing chart. This drive is an after effect of the adjustment of the coefficients (boundaries)
of the filter during filtering (this is classified "on-the-fly tuning"). By using the MATLAB program,
the transient process resulting from the restructuring of the filter was investigated and the
formulas were checked compensation of this transient process. It was found that the application of
such compensation reduced the negative effects of the transition process. This decrease depends on
the order of the filter, the adjustment coefficient (the ratio of cut frequencies before and after adjustment)
and the moment of adjustment (for the periodic signal).

Recent advances in wireless communication technologies have led to the creation of a huge
amount of data that is transmitted everywhere. Most of this information is part of an extensive and
publicly accessible network that connects various stationary and mobile devices around the world.
The capabilities of electronic devices are also increasing day by day, which leads to more data
generation and information exchange through networks. Similarly, with the increasing diversity
and complexity of mobile network structures, the frequency of security breaches in it has increased.
This hinders the introduction of intelligent mobile applications and services, as evidenced
by the wide variety of platforms that provide data storage, data computing and application services to end users. In such scenarios, it becomes necessary to protect data and check their use in
the network and applications, as well as check their incorrect use in order to protect private information.
According to this study, a security model based on artificial intelligence should ensure
the confidentiality, integrity and reliability of the system, its equipment and protocols that control
the network, regardless of its creation, in order to manage such a complex network as a mobile
one. The open difficulties that mobile networks still face, such as unauthorized network scanning,
fraudulent links, etc., have been thoroughly studied in this article. This article also discusses several
ML and DL technologies that can be used to create a secure environment, as well as many
cybersecurity threats. It is necessary to address the need to develop new approaches to ensure a
high level of electronic data security in mobile networks, since the possibilities for improving the
security of mobile networks are limitless.

On the example of a pressure sensor, the problem of selecting a model and parameters of
the conversion function of a microprocessor sensor is considered. The conversion function is
based on a mathematical model that associates the electrical signal coming from the sensor's
measuring transducer with the value of a physical quantity. The model of the conversion function
of a microprocessor sensor must repeat the real spatial dependence of the electrical signal on the
measured value and take into account the influence of external factors, such as temperature. Microprocessor
sensors are used to measure the parameters of an object with a given accuracy. The
main contribution to the measurement error is made by the inaccuracy of the approximation of the
real transformation function by its model. The need to achieve the optimal level of parameter
measurement error in the system, taking into account the complexity and cost of measurements,
requires the control of the sensor error. For this purpose, various models and methods of approximation
are presented. For efficient error control, a method of multi-segment spatial approximation
based on models of linear or non-linear spatial elements is proposed. The error control procedure
is formulated. The procedure for using the model of multi-segment spatial approximation
of the transformation characteristic for pressure calculations taking into account the influence of
temperature is based on the combined use of linear and non-linear spatial elements within the
same model. The segment type selection procedure should begin with an assessment of the possibility
of using a linear spatial element first, and if it is impossible to meet the accuracy requirements,
an analysis of the use of a non-linear element. The method allows you to change the types
and configuration of spatial elements and in this way influence the measurement error. The advantages
of this approach are confirmed by the simulation results.

The article presents an electrodynamic model of the atmospheric surface layer caused by
the action of the electrode effect near the earth's surface, and an analysis of its equations by methods
of similarity theory. Mathematical models of the surface layer electrical state in the approximations
of the classical and turbulent electrode effect are considered separately. In the mathematical
formulation of modeling problems, a number of well-founded physical assumptions were created
that made it possible to obtain analytical solutions to the equations. Analytical formulas have
been obtained for calculating the profiles of aeroion concentrations, the density of the space electric
charge and the electric field in the electrode layer. As a result of mathematical modeling, the
dependences of the electrical characteristics distribution in the surface layer on the values of the
electric field, the degree of air ionization and aerosol pollution of the atmosphere are investigated.
It is shown that the ratio of the electric field values on the earth's surface and at the upper boundary
of the electrode layer is almost constant. The increasing of the electric field, the rate of air
ionization and the presence of sufficient concentration aerosol particles leads to a decrease in the
thickness of the electrode layer and, as a consequence, the scale of distribution of its parameters.
An amplification in the degree of ionization increases, and an increase in the concentration of
aerosol particles in the atmosphere decreases the values of the electric charge density in the surface
layer. Theoretical calculations are in good agreement with experimental data and the results
of numerical modeling of the surface layer electrical structure. The analytical formulas obtained
in the work for calculating the electrical characteristics of the surface layer and the results of
calculations can be useful in solving a number of applied problems of geophysics, in particular for
monitoring the electrical state of the atmosphere.

At present time the problem of developing methods for numerical analysis of RF circuits in the
time domain remains actual because the known Gear and trapezoidal methods used in SPICE simulators
have a number of significant disadvantages. To evaluate the effectiveness of new numerical methods,
special test problems are needed to determine the accuracy of methods in various operating modes.
Numerical analysis of self-oscillating circuits in the time domain offers the most difficulties for circuit
simulation programs (SPICE-simulators) since models of self-oscillating circuits can be both oscillatory
and stiff simultaneously. The aim of this work is to create the model of a self-oscillating circuit that allows
to quantify the accuracy of numerical methods. In accordance with the aim, the following problems
are solved: the features of the numerical analysis of classical self-oscillators in SPICE-simulators are
investigated; the generalized mathematical model of self-oscillating circuits is described; the universal
circuit model of self-oscillating circuits for SPICE-simulators is presented; the quantitative accuracy
assessment of numerical methods of transient analysis in SPICE-simulators was carried out. The model
proposed in this paper makes it possible to determine the relative errors of numerical methods in the
harmonic oscillations mode, in the relaxation oscillations mode, as well as in the «mixed» mode, when
the circuit response contains both exponential components with different rates of change and quasiharmonic
components. The obtained results confirm the high accuracy of the trapezoidal method in the
mode of harmonic oscillations, and the Gear method in the mode of relaxation oscillations. The relative
errors in determining the amplitude of oscillation using these methods for the corresponding operating
modes do not exceed 3%. At the same time, in the «mixed» mode, the relative errors in determining the
amplitude of oscillation for both methods can reach 100%, that confirms the need to use additional
options or special methods of numerical analysis in SPICE-simulators.

One of the most common technological operations is welding of individual parts and blocks.
Welding is widely used in shipbuilding, aviation, defense and chemical industries, in the construction
of oil and gas pipelines. At the same time, very strict requirements are imposed on the quality of the
weld in terms of strength, absence of voids and cavities, operability at high pressures (up to 100 kGf /
cm2) and in a wide temperature range (± 50 ° C). Plasma (argon) welding meets these requirements
most fully. A brief analytical review on the research topic was carried out. It is shown that a promising
direction for the development of plasma welding control systems is the use of hybrid regulators
created on the basis of classical automatic control methods and fuzzy control, formalizing the average
knowledge of experts. The fuzzy component (expert knowledge) should be available for quick and
easy input into the controller. A block diagram and a model of a single channel of a hybrid controller
was developed in the Matlab Simulink environment. The current control channel was modeled using
a fuzzy controller from the Fuzzy Logic library, using the Mamdani fuzzy output algorithm. 19 variants
of linguistic and fuzzy variables were set, the surface of the variable membership function was
obtained. It should be noted that it is possible to quickly enter linguistic assessments of experts into
the memory of the hybrid controller. The behavior of hybrid controller models and standard PI and
PID controllers under a single step action was analyzed. The hybrid regulator provides significantly
better quality indicators (2.5-3 times) than standard regulators. The hybrid controller enters the
steady-state mode after 6s, the PID controller – after 13s, the PI controller - after 15s, and the standard
regulators have an overshoot (first emission) of up to 50%. Thus, the real possibility of constructing
a fuzzy hybrid controller with specified characteristics is shown. It is possible to implement a
hybrid controller in the form of an FPGA.

The protective device (limiter) at the receiver input is an important component, as it ensures
the safety of the receiver operation in conditions of receiving powerful signals. The results of an
experimental study of a protective device in the 1-4 GHz band are presented. It is shown that the
minimum bandwidth losses at a low power level do not exceed 0.63 dB, the maximum bandwidth
losses are 1.23 dB. At an input power of 25 dBm, the protective device operates in a non-linear
mode, therefore it creates harmonics of the input frequency. The experimental amplitudefrequency
response (AFC) of the protective device, as well as amplitude characteristics at three
frequencies are presented. The experiment to remove the frequency response was carried out on a
vector analyzer of circuits. The experiment to remove the amplitude characteristics was carried
out using a standard signal generator and a spectrum analyzer at three frequencies: 1 GHz;
2 GHz; 4 GHz. Structurally, the protective device is a polycor substrate on which all elements
except connectors are placed. The substrate is placed in a frame-type housing and closed with two
sealed lids. Type III sockets according to GOST13317- 89 are used as connectors. A schematic
diagram and a brief description of the design are given. The following main parameters have been
achieved: losses do not exceed 1.23 dB in the operating frequency range from 1 to 4 GHz, theoutput signal power at a high input power level (f = 1 GHz; Rvh = 25 dBm) does not exceed
12 dBm. The protective device is recommended to be used in the input circuits of communication
receivers, navigation, radar and electronic warfare.

The requirements for modern means of technical control and functional diagnostics of
equipment for critical applications are formulated, one of which is the processing of diagnostic
information at a real-time pace. It is noted that for working with digital diagnostic signals, relational monitoring polling devices based on the apparatus of ordinal logic, which gives a significant
time gain over traditional binary logic, are promising. The hardware implementation of ordinal-
logical polling devices in the FPGA basis, along with the obvious advantages of the development
stage, will allow for operational reconfiguration of the internal structure to adapt to the
changing operating conditions of the control object. The hardware implementation of two known
devices is considered. A variable priority device is used to identify the sensor that has detected a
failure or malfunction, with the possibility of setting the sensor number from which the survey will
begin, and the direction of traversing the sensor tuple. The device of centralized control of a group
of objects is used to search for an extreme (maximum or minimum) digital diagnostic signal with
simultaneous determination of the number of the corresponding sensor in one clock cycle of the
monitoring and diagnostic system. The development of combinational data schemes of monitoring
survey devices was carried out by means of ISE Design Suite 14.7. The positive results of testing
the algorithms of the created models are presented, summarized in tables of the states of the inputs
and outputs of the circuits and illustrated by time diagrams of binary signals at the terminals of
the circuits. An estimate of the required FPGA resource costs is given, expressed in the number of
logical elements and user contacts. Also, using the example of low integration devices and the
most resource-intensive samples, the upper and lower estimates of the number of FPGAs of various
types of the Xilinx Spartan-6, Xilinx Virtex-4 families and the domestic 5576/5578 series of
JSC KTC Electronics are given. It is established that with the number of diagnostic sensors up to
200, depending on the FPGA family, up to 17 low integration chips and up to 7 resource-intensive
chips are required to implement one monitoring polling device.

The aim of the study is to develop a method for parametric matching of insulation monitoring
devices, unearthed DC distribution systems and discrete inputs of relay protection.
The use of unearthed DC distribution systems for power supply to relay protection devices
and other responsible consumers makes it possible to ensure high reliability and safety during their operation. It is necessary to ensure uninterrupted power supply to these consumers
even in the event of a ground fault in one of the DC distribution network poles. Insulation
monitoring of the network poles and the prompt execution of repair work when the insulation
resistance falls below the critical level set by the response value, are a guarantee of high
reliability of power supply. The article discusses the reasons leading to dangerous levels of
pole voltage unbalance and false triggering of relay protection discrete inputs during ground
faults of the signal lines connected to them. A method based on multivariate DC analysis is
proposed to determine the matched insulation monitoring response value with the DC network
parameters and discrete inputs parameters, when the conditions for the occurrence of
such accidents are excluded. The influence of insulation monitoring devices in a DC system
on pole voltages unbalance and relay protection operation is also considered. A modification
of the insulation monitoring active method is proposed, which does not create additional pole
voltage unbalance and risks of relay protection misoperation. The operating range of the
static characteristics of the pole voltages and leakage current measuring transducers is narrowed
in the grid unbalanced modes by using a modified active insulation monitoring met hod.
Estimates of the increase in the insulation resistance measurement error arising in these
modes are obtained.

Modern tasks of special areas of robotics, including search and rescue operations in urban
areas, face a number of obstacles to mobile robotics, where the automatic performance of various functions
by mobile robots remains a key task. One of the important requirements for the algorithms and
software of the robot is the possibility of autonomous decision-making and automatic performance by
the robot of various functions, both low and high levels based on the embedded algorithms and information
received from the on-board sensors of the robot. To date, the most common on-board robot sensors
are cameras of various types, due to their technical capabilities and lower cost relative to lidars
and other sensors that provide visual information in the form of digital images. Camera calibration is a
necessary process for extracting accurate information from digital images. This process is necessary to
obtain an exact correspondence between the three-dimensional object space and the pixel space of the
image, for the possibility of subsequent use of computer vision algorithms, aggregation, and information
processing. Calibration of digital cameras is an integral part of a number of practical tasks of machine
vision such as navigation of mobile robotic systems, medicine, reconstruction of dense and sparse threedimensional
maps of the environment, video surveillance and visual inspection, visual simultaneous
localization and mapping, etc. The urgency of the problem of camera calibration is defined by the presence
of many different methods of calibration and calibration templates. Each individual solution is
suitable only for special conditions, e.g., lack of lighting, bad weather conditions, the presence of thirdparty
objects blocking visibility, etc. In most cases, each calibration method uses a specific calibration
pattern. Camera calibration is usually associated with the use of special calibration templates. They
allow to achieve the most accurate results due to a previously known geometric structure. Currently, the
procedure for camera calibrating of robotic systems is carried out in laboratory conditions using the
classic “chessboard” method. In addition, there are only a few alternative approaches that are in their infancy state both in Russia and abroad. On the other hand, research into camera calibration methods
continues and new alternatives for camera calibration are emerging. One of the new directions is the
use of fiducial marker systems as a reference object. A variety of parameters such as the size of the calibration
template, the dimension of the calibration data set, the distribution of distances from the camera
to objects on the stage, etc. creates a vast area for experimental testing of optimal camera calibration
parameters. This paper presents a research of automatic camera calibration using fiducial marker systems
(FMS), which are located on the surface of the robot. Based on the results of virtual experiments
with FMS in the Gazebo simulation environment of the robotic operating system ROS, two different
types of FMS were selected that are optimal relative to other types of FMS covered by our previous
studies in terms of the resistance of FMS to systematic occlusion of the marker area and the effect of
marker size on quality of its recognition. The selected FMS were tested using the onboard camera of the
Russian mobile robot Servosila Engineer in indoor settings to assess the correlation of results in virtual
and real environments.