Single-phase Sr₂FeMoO_6-δ samples with different-degreesuperstructiral ordering Fe/Mo cations superstructural ordering (P, 76, 86 and 93 %) were obtained by the solid-phase technique. Based on the results of measuring the magnetic characteristics in the samples, we found that an increase in magnetization (26.41, 32.36 and 42.66 A·m²·kg^–1), magnetic moment (1.33, 3.07 and 3.58 μ_B/f.u.) and Curie temperatures (422, 428 and 437 K) withparameter P (76, 86 and 93 %) can be explained by the presence of antistructural defects, as well as antiferromagnetic inclusions. This determines the redistribution of electron density, which is accompanied by the change in electronic configuration of a part of Fe/Mo cations. Based on the temperature dependences of the magnetic moment of the samples measured in ZFC and FC modes, and on small-angle polarized neutron scattering (SANS), we found that the samples are in a magnetically inhomogeneous state. An important result to mention is that we detected the difference between the slope of the SANS curves of samples with different oxygen content, which demonstrates a different microstructure of inhomogeneities. The main inhomogeneities are magnetic inclusions with the dimensions depending on the superstructural ordering of Fe/Mo cations. According to the Porod law, it was shown that the Sr₂FeMoO_6-δ samples with wave vector values 0.1 > q > 0.002 Å^–1 contain polydisperse grains with a smooth surface. For q > 0.1 Å^–1 a deviation from the Porod law is observed, confirming the presence of magnetic inhomogeneities with a diameter < 6 nm in the grains.

In this paper we compared the efficiency of the cylindrical, conical, and biconical types of gyrotron resonators. Based on the results of comparing the three studied variants of gyrotron profile, it was concluded that the regular-type profile is the least efficient. This type of a resonator made it possible to achieve the level of efficiency of only 23 %, which can be increased in the regular-waveguide gyrothrons only through several modes or by recovering the electrons on the collector. The medium efficiency option is the biconical profile of the resonator. Its efficiency accounted for 42 %. Through a scientific study we revealed an increase in the efficiency for gyrotrons with conical resonators from 23 to 50 % in the TE₀₁ wave. It is worth mentioning that obtaining such efficiency requires phase grouping of the electrons in an increasing high-frequency field by means of an electromagnetic field with further selection of energy from the electron beam in a strong decaying electromagnetic field. The efficiency of 50 % exceeds significantly that of a gyrotron with a regular cavity profile of ~30 %. The gyrotron efficiency for a waveguide profile with a conical resonator and with recovery on the collector can reach 80 %. To carry out the calculations, the KEDR software package was used, and the optimization of the gyrotron parameters, in particular, was carried out using the GYRO-K software. This software has several advantages over other similar options based on the “PIC” code. GYRO-K makes it possible to obtain a high convergence rate when solving boundary value problems, as well as to solve the problem of optimizing the waveguide profile of gyroresonance devices with an acceptable computational burden. Conical cavity gyrotrons can be widely used in industry to create effective gyrotrons for spectroscopy, diagnostics of various media, and for technological needs.

The paper presents a speech generative model that provides an efficient way of generating speech waveform from its amplitude spectral envelopes. The model is based on hybrid speech representation that includes deterministic (harmonic) and stochastic (noise) components. The main idea behind the approach originates from the fact that speech signal has a determined spectral structure that is statistically bound with deterministic/stochastic energy distribution in the spectrum. The performance of the model is evaluated using an experimental low-bitrate wide-band speech coder. The quality of reconstructed speech is evaluated using objective and subjective methods. Two objective quality characteristics were calculated: Modified Bark Spectral Distortion (MBSD) and Perceptual Evaluation of Speech Quality (PESQ). Narrow-band and wide-band versions of the proposed solution were compared with MELP (Mixed Excitation Linear Prediction) speech coder and AMR (Adaptive Multi-Rate) speech coder, respectively. The speech base of two female and two male speakers were used for testing. The performed tests show that overall performance of the proposed approach is speaker-dependent and it is better for male voices. Supposedly, this difference indicates the influence of pitch highness on separation accuracy. In that way, using the proposed approach in experimental speech compression system provides decent MBSD values and comparable PESQ values with AMR speech coder at 6,6 kbit/s. Additional subjective listening testsdemonstrate that the implemented coding system retains phonetic content and speaker’s identity. It proves consistency of the proposed approach.

The purpose of this article is to analyze methods, approaches, technologies, and means of Internet marketing (IM), using both known and novel technologies: intelligent and blockchain ones. The objectives of the article are to analyze the problems in IM and identify the trends in ITS development in the digital economy using intelligent and block chain technologies, develop new structural solutions, including a portal to support educational activities in general, and plan and search for creative staff in particular. We have analyzed the application of technologies in marketing activities (MA) using cloud computing, determined features thereof and demonstrated some restrictions of MA on Internet. We have also developed the proposals for improving IM in an integrated environment (traditional network and cloud) using intelligent and block chain technologies. The use of intelligent technologies for processing marketing information allows improving the quality and level of return of marketing information systems. The use of block chain technologies will reduce negative subjective interventions and increase the reliability of storing marketing information. It is proposed to develop IM on the basis of a family of intelligent agents for the evolution of intelligent marketing information systems (IMIS). In the article one can see how block chain technology is applied in IM for controlling resources and marketing operations. A new concept for the development of IM and IIMS has been presented whereby the IMIS architecture in the education system is proposed. In addition, we have presented the structure of an intellectual portal based on multi-agent technology that combines the training of university and college graduates and consumers of young professionals in economic sectors.

This paper is targeted at studying the patterns of deposition by electrochemical method of Ni-doped ZnO films, including registering and analyzing their photoluminescence and Raman scattering spectra. We have studied the electrochemical deposition of nickel-doped zinc oxide films on single-crystal silicon substrates from aqueous solutions of zinc and nickel nitrates. The deposition was conducted from aqua solutions of Zn and Ni nitrates in a standard double-electrode electrochemical cell in galvanostatic mode with the current density from 5 to 20 mA/cm² and deposition time from 5 to 30 min. The Raman scattering on nickel-doped zinc oxide films was examined via laser Raman spectrometer SOL Instruments Confotec NR500. The analysis of Raman spectra showed that an increase of cathodic current density deposition leads to an enhanced concentration of a doping agent in the films. Photoluminescence spectra of the samples were registered on a laser spectral measuring system based on monochromator-spectrograph SOLAR TII MS 7504i where a monochromatic line with the 345-nm wavelength, which was extracted from the spectrum of Xe-lamp by means of double monochromator Solar TII DM160, was used as the excitation source. The research demonstrates that the emmission intensity increases with the thickness of the deposited film, and the position of maximums of the radiation line remains unchanged in a visible wavelength range and on photoluminescence spectra with fixed current density. The change in the density of the cathode current leads to a shift in the position of the photoluminescence spectra maximum, which indicates restructuring of defects and dopant atoms in the doped semiconductor, which in turn changes the position of the corresponding levels in the band gap of the material.

This paper considers the problem of memory allocation for the organization of the LIFO-stack in the algorithm for image segmentation based on growing regions is considered. Segmentation divides the image into regions with identical or similar properties and is the most demanding process for the capacity of RAM. The cultivation of areas begins with the neighborhoods of pre-selected initial growth pixels and uses stacks to store the coordinates of adjacent pixels attached to the cultivated region. Stack loading is maximized when the segment size matches the size of the YX image. In the absence of an expression for the exact determination of the size of the stack, it is possible to guarantee the stable operation of the algorithm for growing regions, eliminating the overflow of the memory allocated for processing if the stack size is assumed equal to YX. However, this approach does not take into account the fact that filling the coordinate stacks is also accompanied by a selection of them, which makesthe stack size always smaller than YX. The article proposes an expression that allows one to increase the accuracy of determining the required size of the LIFO-stack for storing the coordinates of adjacent pixels depending on the image size. The expression takes into account the conditions of the maximum load of the LIFO-stack when: a) the segmentation of the square region with the initial growth pixel in the corner of this region is carried out; b) in the scan window, adjacent pixels are always selected in order with the first selectable pixel located in the corner of the scan window. Using the proposed expression to calculate the required capacity of the LIFO-stack under conditions of its maximum load in the image segmentation algorithm based on growing regions provides a 2-fold reduction in the number of LIFO-stack memory cells.

This article is aimed at studying the influence of the entire complex parameters on the characteristics of the obtained thermal images when shooting the Earth’s surface from unmanned aerial vehicles. The values of the minimum detectable and minimum resolvable temperature differences are calculated depending on the parameters of the thermal imager, the survey and the size of the object (spatial frequency) for three serial miniature thermal cameras used in aerial surveys of the Earth's surface from unmanned aerial vehicles. Analytical formulas for estimating the minimum resolvable temperature difference are obtained on the basis of a mathematical model of the thermal imager as a linear system of individual components based on the technique that differs from the generally accepted one. Estimates were made for two cases: observation of a thermal image by an operator on a display screen and for the case when an electronic image is analyzed by a threshold algorithm with no operator engaged. For the first time, the influence of the carrier velocity on the overall modulation transfer function of the system and, accordingly, the temperature and spatial resolution of thermal imagers was taken into account. The main components that must be considered when calculating the full modulation transfer function of the system are: a thermal imager lens, a radiation detector, carrier movement and the observer's visual system. Moreover, the parameters of the detector and the speed of the carrier have the greatest influence on the temperatures resolvable by the system.

This paper suggests an approach to the semantic image analysis for application in computer vision systems. The aim of the work is to develop a method for automatically construction of a semantic model, that formalizes the spatial relationships between objects in the image and research thereof. A distinctive feature of this model is the detection of salient objects, due to which the construction algorithm analyzes significantly less relations between objects, which can greatly reduce the image processing time and the amount of resources spent for processing. Attention is paid to the selection of a neural network algorithm for object detection in an image, as a preliminary stage of model construction. Experiments were conducted on test datasets provided by Visual Genome database, developed by researchers from Stanford University to evaluate object detection algorithms, image captioning models, and other relevant image analysis tasks. When assessing the performance of the model, the accuracy of spatial relations recognition was evaluated. Further, the experiments on resulting model interpretation were conducted, namely image annotation, i.e. generating a textual description of the image content. The experimental results were compared with similar results obtained by means of the algorithm based on neural networks algorithm on the same dataset by other researchers, as well as by the author of this paper earlier. Up to 60 % improvement in image captioning quality (according to the METEOR metric) compared with neural network methods has been shown. In addition, the use of this model allows partial cleansing and normalization of data for training neural network architectures, which are widely used in image analysis among others. The prospects of using this technique in situational monitoring are considered. The disadvantages of this approach are some simplifications in the construction of the model, which will be taken into account in the further development of the model.

The article presents some findings on the potential of analytical methods for the synthesis of broadband matching circuits for solving nontrivial circuit engeneering problems. Nontriviality shows itself in the technique for the assignment of the frequency response model (approximation) for the broadband synthesis in cellular communication, when double-band antennas are essential. The frequency response model appears as the result of frequency transformation, which yields in the assignment of both bands at the very first stage of the synthesis. The bands’width and isolation between them may be controlled independently, which is the essential part of the frequency transformation. Such way offrequency response assignment allows the potential of the method, which is always restricted by a load, to find broader application. In these conditions the frequency response turns to a quasi-double and asymmetrical one due to finite isolation between bands. We also present the general approach to the synthesis, which incorporates both the frequency transformation and novel synthesis technique. The modified frequency transformation can be applied to all types oftraditional approximations of arbitrary orders in synthesizing broadband frequency-selective matching devices. The distinctive feature of this technique is in the use of generalized Darlington’s synthesis for solving the problems of broadband matching of resistances in a lumped element basis with the application of frequency reponses obtained through modified frequency transformation. We have also estimated the efficiency of the developed technique by comparison with the known results.

The purpose of the article is to describe the methodology and hardware for determining the force required for the movement of the plunger rod of a single-use syringe. The measurement method is used to obtain new experimental data. We first-ever obtained the oscillograms of force variation required to move the plunger rod of test syringes and found that, compared to a two-component, three-component syringe is characterized by significantly smaller values of the effort required for the plunger rod to move. So, when it moves without using water, the F value at the beginning of the suction stage is 1.5 times less than that of a two-component syringe and 2.4 times less at the extrusion stage. The use of water increases the force required to move the rod-piston of the test syringes. Thus, for a two-component syringe the force at the suction stage without using water was 4.5 N and 5.5 N – at the extrusion stage, and with the use of water, the values of these forces, respectively, increased to 6.5 and 6 N. For a three-component syringe without water, the plunger rod displacement force at the suction stage was 2.9 N and at the extrusion stage – 2.3 N, and with water the values of these forces increased to 3.7 and 2.9 N, respectively. The device developed makes it possible to conduct comprehensive studies of the effect of the type of syringe, its capacity, the speed of movement of the plunger rod, the duration of the stop between liquid suction and extrusion stages and other parameters on the amount of forces required to move the plunger rod of the syringe. This will allow you to justify the conditions and the normalized value of the force (or forces) required for the movement of the plunger rod when testing syringes by this indicator.

The paper describes the application of the optimization method of fuzzy automatic classification in the problem of combining estimates of trajectory measurements in a radar system. By a radiolocation system the author mean an automated hierarchical technical complex that combines, using communication tools, a set of asynchronously functioning radiolocation tools, as well as central and intermediate points that collect, process and issue trajectory radiolocation information. It must be borne in mind that in conditions of tracking tight groups of air targets, with relatively small intervals and distances, it is not always possible to obtain trajectory information of the required quality. The main reason for this is the difficulty in determining the values of the correlation matrices of errors in estimating the parameters of the state vector of air targets. The task becomes more complicated as the number of intermediate processing points increases when it is brought to the final consumer. The main goal of the article is to increase the accuracy of estimates of trajectory measurements in a radiolocation system. The research is done by means of the mathematical tool of fuzz-set theory, namely, by optimizing fuzzy automatic classification. The article demonstrates that using fuzzy automatic classification under a priori parametrical uncertainty in the law of trajectory measurement errors, when determining weight coefficients, can improve the accuracy of estimates in these conditions up to 30 % compared with methods based on the application of the probabilistic approach. The results obtained allow us to justify the prospects of using optimization methods of fuzzy automatic classification in the tasks of processing trajectory information. In addition, the advantage of the proposed method is its low computational complexity and ease of implementation, which is especially important while maintaining a large number of airborne objects.

The article considers the method of image processing proposed by the author in relation to the problem of automatic detection of moving objects in optoelectronic thermal imaging systems. Moving objects on the observed scene are subject to investigation, so it is advisable to use algorithms based on background subtraction methods to solve the detection problem. However, the observed objects may include objects of interest (a person, a vehicle), as well as other objects and background elements that increase the noise component of the observed situation. Also, the increase in the noise component is greatly influenced by false segmentation in the foreground of the areas of processed images when transferring the field of view of the sensor of the optical-electronic surveillance system. The purpose of this article is to prove the reduction of the probability of false alarm of an automatic detector due to the author's proposed approaches to image processing. The research uses the mathematical apparatus of probability theory and simulation with subsequent statistical processing of data. The article shows that the probability of a false alarm of an automatic detector based on the background subtraction method increases significantly after the transfer of the field of view of the sensor of the optical-electronic surveillance system and decreases after the movement stops as the areas of the processed image that are falsely highlighted in the foreground are automatically segmented. The simulation showed that the approaches proposed by the author can increase the peak signal-to-noise ratio of processed images and reduce the probability of a false alarm of the automatic detector of objects of interest. The results obtained show the feasibility of adapting detection algorithms based on background subtraction methods to work in scanning optoelectronic surveillance systems.

The paper is purposed to establish the principles of the micro-structural changes of Pt-Si system during the rapid thermal treatment. The Pt films 43.7 nm thick were applied on the substrates of mono-crystal silicon KEF 0.5 with orientation (111) by means of the magnetron platinum target sputtering (purity of 99.95 %) on the unit MPC 603 with the cryogen pumping to the pressure of no less than 5∙10^-5 Pa. Argon was used as a working medium, whose purity constituted 99.933 %. Rapid thermal treatment was performed in the mode of the thermal balance with irradiation of the reverse side of the wafer by means of the non-coherent light flow in the nitrogen medium within the temperature range from 200 to 550 °C with a step of 50 °С during 7 s. In parallel, the solid phase synthesis was performed of platinum silicide by means of the standard method with application of the continuous single stage thermal treatment in the analogue medium (T = 550 °C, t = 30 min). Temperature monitoring was performed by means of the thermal couple method with accuracy of ±0.5 °C. The grain size was determined by the translucent electron microscopy method. Thickness of platinum silicide under formation, its surface micro-relief and the separation boundaries with silicon were determined by means of the raster electron microscopy. It is demonstrated, that with the rise of the rapid thermal treatment one can observe growth of the platinum film on silicon. A comparative analysis was conducted of the average size of grains, micro-relief of the PtSi surface and its separation boundary with silicon for two methods of its formation with application of the rapid thermal treatment and with application of the traditional continuous thermal treatment at the temperature of 550 °C during 30 min in the nitrogen atmosphere. By means of the raster electron microscopy method it is demonstrated, that size of the micro-relief on the separation boundary of PtSi-Si does not exceed 15.9 nm and the size of grains is 37.7 nm. This is in 2.5 and 3.1 times smaller, then in the case of the traditional single stage continuous thermal treatment.