The special procedure for the formation of reference values for a set of signals from telecommunication and radioelectronic systems (STR) has been developed based of the proposed library of auxiliary functions, which provides simplicity, ease of use and significantly expands the possibilities of signal modeling. An operator model of the response of an arbitrary linear system to a composite trapezoidal (periodic, non-periodic finite) signal is constructed. The mathematical model (in the time domain) of the linear system reaction to a set of the STR signals has been built, varying in form, time of existence, and method of assignment. The unified algorithm for mathematical modeling of linear distortions of the STR signals has been developed. In accordance with the latter, an ease of use of the program for mathematical modeling of the STR signal set in the time domain has been developed, representing the investigated reaction in graphical (with the ability to scale along the axes), tabular, and file forms.

The achievement of a higher quality signal processing occurs, among other things, due to the complication of its processing algorithms, i. e., an increase in the amount of calculations. This processing must be carried out in real time. One of the ways to overcome this problem is to split a complex algorithm into several simpler parts that must be executed in parallel and then combined. For this purpose, digital computing platforms are used, which are built on the basis of various discrete elements, such as programmable logic integrated circuits, microcontrollers or multi-core digital signal processors. Based on the results of the research, a mathematical expression was obtained that shows that the final signal-to-noise ratio significantly depends on the processing frequency. This ratio also depends on the element base on the basis of which digital processing algorithms are implemented. Using the characteristics of individual chips as an example, it is shown that the use of certain chip types is preferable in some cases because it allows the processing to be implemented in a wider clock frequency range.

The purpose of the article is to outline the procedure and the results of the study of the influence of the distance from the sound source to the transformer on speech intelligibility and speaker recognition by voice during electro-acoustic conversion in a transformer. Of all the existing methods for measuring speech intelligibility and voice recognition, the objectified method of articulatory syllabary tables was used. The choice of the method is due to the fact that with a large number of dictated and, accordingly, adopted syllables, the influence of various factors is averaged out. Averaging also occurs if different groups of speakers and auditors take part in the tests. This is the objectivity of the articulatory method. Objective results can also be obtained by using speech to precisely reproduce sound combinations that do not have a semantic load, since when receiving words or phrases, it is possible to think out and restore the elements of the speech distorted by the communication path. The experimental procedure was determined. For the study, a transformer was used as an electroacoustic transducer, and a multifunctional search device ST031M “Piranha” was used as a control and measuring equipment. The selection of speakers and auditors was carried out for the research team. The selection was carried out among men and women between the ages of 18 and 30 who had no obvious speech and hearing impairments and were native speakers of the Russian language. The dependences of the values of the level of speech intelligibility and recognition of the speaker's voice on the distance between the sound source and the transformer are derived. The distances from the sound source to the transformer are determined, at which speech intelligibility corresponds to different quality classes according to GOST 16600-72.

The article considers the approach proposed by the authors to evaluate the effectiveness of image processing in detecting moving objects by an optoelectronic surveillance system. The variety of indicators currently used by researchers to assess the quality of image processing suggests that common approaches have not yet been developed. The application of specific indicators is determined by the features of the implemented approaches to the image processing, as well as the specifics of the task in the interests of which the processing is carried out. The problem considered by the authors, assessing the effectiveness of the developed image processing method in relation to the problem of detecting moving objects by an optoelectronic surveillance system, determines the need for its consideration in two directions. The first is from the point of view of the effectiveness of the implemented approaches to image processing in order to increase the peak signal-to-noise ratio. The second is, in terms of increasing the efficiency of the automatic detector, by reducing the level of its false alarm. At the same time, the need for additional determination of the probability of correct detection and the construction of detection curves is mandatory, since in their entirety they are generally accepted indicators of the quality of detection. The application of the proposed approach will allow further comparison of the quality of the developed image processing method with other similar methods, as well as evaluation of the work of newly developed ones.

When evaluating the individual reliability of semiconductor devices by gradual failures for a given operating time, the value of the electrical parameter of a particular instance for this operating time is predicted using the simulation method. To obtain a prediction of an electrical parameter, it is necessary to have a simulation model in the form of a function of the relationship between a given operating time and the level of simulation impact. The simulation model is obtained with the help of preliminary studies (training experiment) of a training sample of semiconductor devices of the type of interest with the volume of approximately 50 ... 100 copies. The application of the model is reduced to the calculation of the level of simulation impact corresponding to a given operating time. The result of measuring the electrical parameter at the calculated level of the imitation impact in a new specimen of the same type that did not take part in the training experiment should be considered as a prediction of this parameter for a given operating time. An integral part of the preliminary research to obtain a simulation model is the testing of semiconductor devices of the training set for a long operating time, which can be tens of thousands of hours, which necessitates planning and conducting accelerated tests. The article substantiates the conditions for conducting accelerated forced tests in relation to high-power bipolar transistors of the KT872A type. The increased temperature and the reverse voltage applied to the collector junction of the transistors are chosen as factors accelerating the tests. The test acceleration coefficient is calculated relative to the operating mode of the transistors. Based on the results of the accelerated tests for the electrical parameter (collector-emitter saturation voltage), a mathematical model was obtained in the form of a dependence of its average value on the operating time. The presence of this model is necessary to determine the function of recalculating the given operating time of transistors to the value of the simulation impact.

Researches of the electrophysical characteristics of gate dielectrics obtained by the rapid thermal processing (RTP) method by two-stage and three-stage processes have been carried out. Each photonic processing (stage) was carried out for 12 s at a constant power of halogen lamps and heating the wafers to a maximum temperature of 1250 °C. The first two stages of the process were carried out in an oxygen atmosphere, the third - in nitrogen or a forming gas. It was found that for dielectrics obtained by the process with final processing in a nitrogen atmosphere, the absolute value of the voltage of flat zones is 0.42 V less, than for insulators, formed by a two-stage process. This is the consequence of the elimination of a significant part of the defects, responsible for the presence of Coulomb centers in the dielectric layer. Carrying out photonic processing in anitrogen atmosphere at high temperatures of procedures for proceeding of the restructuring of the structure of the dielectric layer. For insulators obtained by a three-stage process with final processing in N₂, an increase in dielectric strength and breakdown voltage by 1 V and 3.3 MV/cm, respectively, is observed in comparison with dielectrics, obtained by a two-stage process. An increase in dielectric strength indicates relaxation of elastic stresses of deformed bonds and compensation for dangling bonds both in the dielectric and at its interface with Si during high-temperature photonic treatment. Passivation by nitrogen atoms of deformations at the dielectric/semiconductor interface will also have a positive effect on the strength of the insulator.

The possibility of pyrolytic synthesis of composite heterosystems based on macroporous silicon, graphitic carbon nitride and wide band semiconductors zinc oxide and zinc sulfide (g-C₃N₄/ZnO/ZnS) from a mechanical mixture of thiourea and zinc acetate at 500 – 600 °C was shown. The obtained material study by scanning electron microscopy and energy dispersive X-ray spectroscopy showed a uniform filling of macroporous silicon with the composite g-C₃N₄/ZnO/ZnS with the formation of a continuous composite film on the surface. The photoluminescence of the samples was controlled by the synthesis temperature. Increase of photoluminescence leads to shift of luminescence maximum in high energy range from 544 to 516 nm. It was found that photocatalytic activity of composite heterosystems obtained at a lower temperature is higher due to more developed surface morphology and smaller bandgap width. The materials obtained can be used to create photocatalytic coatings and functional layers of optoelectronic devices.

The results of a comparison of the exchange interaction mechanisms in low dimensional magnetic systems are presented. It has been shown that ZnO crystal may be used as a semiconductor non-magnetic matrix for the formation of quasi-one-dimensional and quasi-zero-dimensional magnetic systems by introducing impurity atoms of Cr, Mn, Fe, Co and Ni. Structural parameters, electronic and magnetic properties were calculated at the atomic level in the framework of quantum mechanical simulation. The exchange interaction integrals were calculated at the microscopic level using the Heisenberg model. The exchange interaction mechanisms were determined on the obtained dependences of the exchange interaction integral on the structural and electronic properties, as well as on the features of the low-dimensional magnetic systems partial density of electronic states. The results of studying the exchange interaction mechanisms in two-dimensional magnetic systems formed in materials of the MAX₃ (M= Cr, Fe, A = Ge, Si, X= S, Se, Te) group are summarized. The established mechanisms made it possible to compare the conditions for the formation of a ferromagnetic order in systems with different dimensions of magnetic interaction. The ferromagnetic order in all the structures under study is formed due to the indirect superexchange interaction between orbitals of different symmetry. Strategies aimed at enhancing the superexchange interactions between orbitals of different symmetry or attenuating the contributions of the exchange interaction between orbitals of the same symmetry contribute to the formation of stable hightemperature ferromagnetism.

The methods of constructing physical unclonable functions (PUF), which are the basis of physical cryptography, are analyzed. The broad applicability of the Arbiter PUF, based on the analysis of the delays of the signal transmitted along two paths, is noted. It is shown that the randomness of the delays is explained by technological variations in the manufacturing process of PUF and their dependence on the use of homogeneous repeating elements that ensure the symmetry of the paths. As an alternative to the existing solutions, the article proposes a new approach for constructing an Arbiter PUF based on asymmetric paths. The sources of randomness as logical element delays are investigated. Their diversity and distinctive characteristics are shown depending on the number of inputs to which an active signal is supplied and the values at other inputs. A technique for balancing a set of pairs of paths of Arbiter PUF is proposed, which lays in regulating the duration of the impulse test signal depending on four types of path asymmetry. New structures of Arbiter PUF with asymmetric pairs of paths are proposed. Experimental studies confirm the possibility of using various sources of randomness in the form of signal delays.

The purpose of the article is to analyze methods, approaches and means of Internet of Things (IoT) technology for product quality control. The objectives of the article are: analysis of dairy farm management problems, development of the structure of the IoT network for milk quality analysis, development of an algorithm for the operation of the IoT milk quality control network, optimization of IoT network protocols choice. Two types of management are considered for the functioning of a dairy farm: production and processes. To implement dairy farm management using 4.0 technology, the use of an IoT network is proposed, in which various communication protocols are considered. The structure of the IoT network of four-level dairy farm management is proposed, which includes analyzers, a gateway, a cloud platform and various applications for farmers and operators. A generalized algorithm for milk quality control on a farm based on the developed IoT network structure is presented, which includes receiving information from analyzers, transmitting it through a gateway to a cloud platform for storage and intelligent processing, displaying results through operator applications. The application of intelligent algorithms for farm management is also considered: data processing and training ‒ ML, knowledge processing ‒ DT, security ‒ FL. The process of selecting a suitable network protocol for monitoring a dairy farm is carried out using the hierarchy analysis method, which uses expert estimates corresponding to four network indicators: transmission speed, distance, frequency and security. The formulated approaches can be applied in various production processes to monitor product quality.

The production activity of many industries is associated with the release of highly dispersed particles and aerosols, as well as the subsequent capture of fine particles. Such processes take place, for example, in the production of fillers and polymers, powdered pigments and chemicals, carbon black, plant protection chemicals, lime and cement, pulverized quartz and asbestos, in the melting of non-ferrous and rare metals. According to doctors, highly dispersed particles, penetrating into the alveoli of the lungs, cause various occupational diseases of workers in the mining, coal, machine-building industries – pneumoconiosis. For example, when working in the environment containing silicon dioxide dust, workers develop one of the severe forms of pneumoconiosis – silicosis, and exposure to beryllium dust causes a very serious disease – berylliosis. To purify air and other gases from mechanical impurities, a variety of physical forces and means are used: gravitational forces, inertial forces, centrifugal forces, electric interaction forces of charged particles, capillary forces, as well as filter partitions with the appropriate pore size. To solve the problem of cleaning indoor air from highly dispersed particles and aerosols that cause the greatest harm to health, in this paper it is proposed to use electrostatic filters that provide filtration in an electric field through highly porous cellular materials. As a result of the theoretical and experimental studies, the parameters of the cleaning process and the design parameters of the electrostatic filter were determined, ensuring high process performance and the degree of purification.

The effectiveness of biofeedback trainings to develop relaxation skills was investigated using the NeuroDog hardware and software complex. Discriminant analysis (a method of multivariate statistical analysis) was carried out, which made it possible to assess the quality and accuracy of the grouping of drivers and assistant drivers of locomotive crews into groups with varying degrees of successful development of the relaxation skill. Highlighted the most informative signs of dividing drivers into groups. The accuracy of the presented groups was checked using linear qualification functions, the informativeness of the features was assessed by Fisher's F-criterion. The critical level of significance when testing statistical hypotheses is p < 0.05. In the course of discriminant analysis, a number of characteristics necessary for the interpretation of groups and their differences were calculated, such as: linear classification functions, canonical discriminant functions, and factor load of canonical discriminant functions. Informative differential diagnostic signs for diagnostics of locomotive crew drivers for the development of relaxation skills were shown. Formulas of linear qualifying functions are given. The diagnostic accuracy was 84.91 % on average.