Vol 18, No 2 (2022): Вестник Воронежского государственного технического университета

we considered the features of estimating the parameters of a linear regression model using the continuous form of the maximum consistency method (CMCM) between the calculated and actual values of the dependent variable. At the same time, the discrete form of such consistency is formally expressed by the sum of the number of coincidences of the signs of increments of these values on all pairs of sample observation numbers. We carried out computational experiments with four-factor and five three-factor versions of the model for the length of main gas pipelines and gas pipeline branches in a single-line calculation. The independent variables used were the volume of production of stable gas condensate and oil, explored and proven reserves of natural gas, explored reserves of gas condensate. As a result of the experiments, we studied the following questions: elucidating the influence of the values of the compromise parameter between the CMCM -estimates of the parameters and the estimates obtained by the method of least modules; identifying the ranges of change of the nontriviality point in a linear programming problem that implements CMCM; assessing the adequacy of model options

the article discusses the process of developing a distance learning system for the effective organization of the educational process of a departmental university, based on the Moodle distance learning platform. In the course of solving the task, we developed the information structure of the electronic courses of the Vladimir Law Institute of the Federal Penitentiary Service of Russia, created new system user roles, which make it possible to make work in the system safer and more convenient, including from the point of view of controlling the educational process as a whole and the activity of each user. For professors, a typical structure of an electronic course is proposed, which makes it possible to conveniently place methodological materials on the disciplines taught, receive feedback from students, and carry out various types of control over the formation of students' competencies in accordance with the work programs of disciplines. Such a structure makes it possible to reflect the results of the current monitoring of the progress of students in the study log, which is a distinctive feature of the organization of education in a departmental university. For students, we proposed an author's algorithm for completing an electronic course, which can be implemented both in distance or blended learning formats, and in full-time learning. On the example of information support of distance learning for the discipline "Information technologies in legal activity", the process of forming a database of test items is described. Experimental testing, conducted by the author among students following the results of studying the discipline "Information Technologies in Legal Activity", showed the effectiveness of the chosen approach to organizing electronic courses in the electronic information and educational environment of a departmental university

the article proposes the design of a substrate integrated waveguide (SIW) for communication tasks in 5G n261 networks (27.5-28.35 GHz). Thanks to the proposed design, it becomes possible to form radiation in three directions for the best quality of communication with a cellular subscriber. The proposed design can be used to create mini cells that provide coverage with 5G access networks in small areas. Through the use of a thin dielectric, it is possible to achieve a low profile of the antenna system and control the use of a system of electromagnetic waves that extract the metal rods that form the waveguide. Removing the pins opens the channel for the propagation of electromagnetic waves, which in turn makes it possible to connect the selected antenna element. As a result, we found that the final system has a high efficiency, high radiation efficiency. The results obtained are confirmed by the pictures of the directional diagrams, the electromagnetic field, the graphs of the scattering matrix. The use of a highly stable dielectric ensures that the return loss level is less than -10 dB in the operating frequency range, and the transmission coefficients are not less than -3 dB, which makes it possible to achieve the most optimal characteristics of the developed antenna design with SIW

when carrying out radio monitoring of satellite communication lines by the method of active diagnostics of their relay paths, it becomes necessary to solve a number of problems of searching, detecting and comparing diagnosed satellite communication lines with a repeater specified for monitoring in order to identify reliable information about the actual use of the allocated frequency resource and its compliance with the issued operating permits radio electronic means. In the presence of undocumented possibilities for changing the configuration of relay paths and the possible functioning of unauthorized radio electronic means, solving the problem of recognizing observed radio emissions becomes the most urgent task. The aim of the work is to determine at a qualitative level the potential possibilities of recognizing radio emissions during radio monitoring of satellite communication lines by the method of active diagnostics of their relay paths. The element of novelty of the presented approach is the compilation of a glossary of recognition features from the most informative parameters of radio emissions, which make it possible to trace the characteristic features of the controlled relay paths. We showed that by monitoring for a certain time the change in the parameters of the diagnostic signal, it is possible to achieve an unambiguous solution to the problem of determining whether the observed satellite communication lines belong to a controlled relay satellite. The proposed approach makes it possible to substantiate the rational requirements for the dictionary of radio emission recognition features in the radio monitoring of satellite communication lines using the method of active diagnostics of their relay paths

we developed a method for calculating the probabilistic characteristics of detecting a radio signal with a random initial phase and amplitude. We obtained analytical expressions for the probabilities of correct detection and false alarm when using piecewise linear approximation in solving devices. We used a piecewise linear solving function in a threshold device, which, unlike binary, is most accurately suitable for describing the real transients of the components of the element base, due to the difficulties of implementing in practice instantaneous changes in the stable states of the solver for a number of reasons, which include the dynamically changing noise environment of the operating conditions of detection systems and the need for instant adjustment of their parameters. When the samples of the receiver's output effect fall into the uncertainty zone formed by the piecewise linear solving function, these samples undergo additional iterations, which will allow us, in a number of restrictions imposed on the reception conditions, to increase the efficiency of signal detection. We performed a simulation, based on the results of which the characteristics of detecting a signal with a random initial phase and amplitude under the influence of white Gaussian noise are constructed. The presented detection curves allow us to evaluate the consistency of the obtained analytical expressions and compare them with those available in the known literature

the article discusses a reflector antenna developed on the basis of the "substrate integrated waveguide" (SIW) technology. We formed, an electrodynamic model of a horn radiator with a trapezoidal dielectric lens to improve the characteristics of the radiator to study the full characteristics as well as to determine the range of operating frequencies. The obtained results of modeling the emitter showed that SIW antennas have high quality indicators, as well as ways to ensure high efficiency in a wide frequency range. On the basis of the design of the horn SIW antenna, we formed a reflector SIW antenna with two types of design: a mono-board structure, when the antenna and reflector are located on a single dielectric rectangular substrate, and also a design with minimal use of dielectric. The resulting designs were investigated using electrodynamic modeling, which showed that SIW reflector antennas have high quality characteristics - high directivity, total efficiency, and also have a narrow directional beam of the main lobe of the directional pattern. On the basis of the obtained structures, we made conclusions about the possibility of using the SIW technology in reflector antennas of the millimeter range of radio waves

the article analyzes the basic dual spherical electro-induction sensors of electric field strength in order to identify their design parameters and parameters of the interaction of sensors with the EP, affecting the error of its perception. We carried out optimization of the sensor's sensitive elements in order to identify the minimum error and the maximum of its spatial measurement range, in which its minimum error is ensured. Optimization made it possible to reduce the error of the basic sensors by approximately two times, i.e. from ± 4.6% to ± 2% and to offer three possible variants of the implementation of the sensitive elements of dual sensors. In the first variant, the angular size q₀₁ of the second pair of sensing elements is increased from 45⁰ to 47⁰. This made it possible to reduce the sensor error to ± 2.1% at the upper limit of the spatial measurement range a = 0.93. In the second variant, the angular size q₀₂ of the first pair of sensing elements is increased from 45⁰ to 47⁰, with a constant size q₀₁=90⁰ of the same pair, and the angular size q₀₁ of the second pair of sensing elements is also increased from 45⁰ to 47⁰. This made it possible to reduce the error of the second version of the sensor to ± 2.1% at the upper limit of the spatial measurement range a =0.93. In the third version, the angular size q₀₂ of the first pair of sensing elements was reduced from 45⁰ to 40⁰, with a constant size q₀₁=90⁰ of the same pair, and the angular size q₀₁ of the second pair of sensing elements was reduced from 45⁰ up to 35⁰. At the same time, the sensor error in the entire spatial range does not exceed ± 2%. Using dual sensors of three versions, it is possible to achieve a significant increase in the accuracy of measuring the strength of inhomogeneous EP in a wide spatial measurement range compared to basic sensors, while the third option is preferable

the work is devoted to the issue of detection of defects such as "pores" in steel welded joints made with full penetration of the root of the weld. We considered the classification of defects, the causes of their occurrence, as well as their influence on the performance of a part or structure. We described the factors that reduce the probability of detecting this type of discontinuity by ultrasonic testing, in particular, by the echo-pulse method. Welded joints made of Steel 20 with a nominal thickness of welded elements of 12 mm were used as the object under study. In these samples, according to the results of radiographic control, unacceptable internal defects were revealed in the form of porosity, accumulations and chains of pores. The purpose of the experiment was to determine the possibility of detecting such defects by ultrasonic testing. We describe the equipment used and the methodology for conducting the experiment. We determined the modes of control, scanning and selected the dimensions of the control reflectors in the tuning sample, which imitate a natural defect in the product, respectively, their size is equivalent to the maximum allowable single defect in the test object. During the ultrasonic testing, internal pores were fixed, but the amplitude of the echo signal from these defects was significantly lower than the rejection sensitivity level. We tabulated the results and plotted the indications found against sensitivity levels. None of the indications found during radiographic control exceeded the control level of sensitivity, i.e. fixation level

the article is devoted to solving problems of determining the most significant parameters for the anodic dissolution of a conductive material in the electrolyte medium, implemented according to the scheme with fixed electrodes. With such scheme for part processing, deviations from the required geometric parameters characterize both the accuracy and the quality of the surfaces being machined. The use of experiments planning method made it possible to establish the influence of several factors on electrochemical processing of samples made of steel 40X13 on the specific material removal, non-flatness and non-parallelism of the treated surfaces relative to the working end of the electrode-tool. The anodic dissolution of the cylindrical samples end surfaces with the diameter of 11 mm and height of 6 mm was carried out with a longitudinal electrolyte flow in the SEHO-901 serial machine-tool with adaptive processing modes. The factors to be studied were the following: the interelectrode gap, the voltage on the electrodes, the concentration of the electrolyte, the temperature and speed of the electrolyte flow, and the hydrogen index. At the same time, a series of experiments was planned in such a way that each of the factors varied at two levels, symmetrical with respect to the base one. The use of regression analysis in the planning of experiments made it possible, as a result of carrying out, to exclude insignificant factors and to establish the main factors influencing the formation of macroroughness: interelectrode gap; concentration and velocity of the electrolyte in the gap