×

You are using an outdated browser Internet Explorer. It does not support some functions of the site.

Recommend that you install one of the following browsers: Firefox, Opera or Chrome.

Contacts:

+7 961 270-60-01
ivdon3@bk.ru

  • Methodological foundations of working with the Modbus TCP protocol with an example in the high-level Python programming language

    This article explores a method for executing data collection systems based on the widely-used industrial protocol, Modbus TCP. In this configuration, the server is a program emulating the Modbus TCP protocol.To implement the client an algorithm and furnished a practical Python programming illustration that employs a lower-level socket library.

    Keywords: python, socket, modbus

  • Road sign detection based on the YOLO neural network model

    This article presents a research study dedicated to the application of the YOLOv8 neural network model for road sign detection. During the study, a model based on YOLOv8 was developed and trained, which successfully detects road signs in real-time. The article also presents the results of experiments in which the YOLOv8 model is compared to other widely used methods for sign detection. The obtained results have practical significance in the field of road traffic safety, offering an innovative approach to automatic road sign detection, which contributes to improving speed control, attentiveness, and reducing accidents on the roads.

    Keywords: machine learning, road signs, convolutional neural networks, image recognition

  • Automated system for issuing bank guarantees based on forecasting the execution of government contracts

    In order to provide information support for decision-making on the issuance of bank guarantees for the execution of a contract in the field of public procurement, it is important for banks to obtain historically accumulated information on the execution of government contracts. This is necessary to assess the possibility of the supplier's performance of his future contract. This can be done by collecting and aggregating information about contracts from the Unified Information System in the field of procurement. The paper proposes to use IT technologies and data analysis to predict the performance of the contract and identify bona fide suppliers. In the work, a selection of primary data on contracts was formed for modeling using the parsing of the FTP server of the Unified Information System in the field of procurement, and the parsed data was preprocessed for use in machine learning models.

    Keywords: information system, data analysis, government contract, data parsing, machine learning

  • Computer simulation of interaction of silicate and phosphate additives by quantum chemical analysis

    This paper presents two methods of computer simulation (quantum chemical analysis and molecular dynamics) of the interaction of additives with the iron surface. Quantum chemical interaction of silicate and phosphate additives with iron surface was carried out. The plate model was used for quantum chemical analysis, calculations were carried out in the DFT approximation. The method of molecular dynamics is based on the calculation of the evolution of the system of interacting particles of atoms and molecules by integrating the equations of their motion. It is shown that the oxidation of the surface leads to a decrease in the adhesion energy of both individual additives and their combinations, allowing to find the influencing factors on the behavior of tribosystems.

    Keywords: lubricant, method, quantum chemical analysis, molecular dynamics, tribology, friction, computer simulation

  • Comparative analysis of recursive methods of frequency estimation

    The paper presents results of a study of operational recursive methods for quasiharmonic signals frequency estimating over a short observation interval. Such methods should be used, for example, for adaptive control of directional pattern of hydroacoustic antennas in inhomogeneous medium. We proposed recursive expressions for realizations of four methods of frequency estimation within the limits of sliding observation interval. The expressions require a minimum number of mathematical operations, which does not depend on the observation interval length. We carried out comparative analysis of the speed, accuracy, and stability of the methods. The stability of the methods was analyzed based on results of model signals processing with constant amplitude, frequency, and initial phase in presence of additive white normal noise. The accuracy was investigated by the processing results of signals with slow varying amplitude and phase. The paper also presents the results of processing of long sequences of modulated signals with additive noise within a sliding window with predetermined duration. The obtained results make it possible to select from among the four methods the optimal one according to one or more criteria.

    Keywords: communication channel, directional pattern, frequency estimation, recursive method, accuracy of method, stability of method, sliding interval

  • The evolutionary transformation of polarization of optical radiation based on weakly guiding waveguides in glass

    The new polarization integrated-optic scheme based on weak-guided waveguide in glass is proposed - the passive 90-degree convertor of linear polarization. The converter has the evoulution type of it working principle. Converter consists of four-layer waveguide, which includes ion-exchange waveguide in glass with high-index cladding film, having tapered thickness or (in another variant of converter) tapered width. The working principle of converter has been explained with mode analysis techniques. The calculations showed that in the small range of thickness (or width) of nano-scaled cladding film the second and third waveguide modes have nearly equal effective indices and hybrid structure of fields, and out of this range the same modes have the field structure of modes TM0 and TE1. The smooth (adiabatic) increase of waveguide cladding film thickness (or width) along it longitudional geometric axis means that such waveguide is a polarization converter, which transforms mode TM0 to mode TE1.

    Keywords: Integrated optics, polarization converter, optical waveguide, guided-wave mode

  • The correctness of the problem of antenna pattern adaptive control in an inhomogeneous medium

    The paper is devoted by studying of the correctness of the antenna pattern adaptive control problem in a randomly inhomogeneous medium. We use spectral methods for the solving the Helmholtz equation with variable parameters in the frozen medium approximation. We have proved the correctness of the problem of a given antenna pattern forming in a randomly inhomogeneous medium for the measured distribution of the complex wave amplitude in the plane of receivers in the first time. The possibility of using an antenna with a synthesized aperture for adaptive correction of the antenna pattern for maximization of communication channel capacity is substantiated. We use the refractive index model as the sum of the deterministic and random components in numerical modeling. The sampling intervals were chosen in accordance with the sampling theorem. The analytic expressions with given parameters were used as a model of the law of the antenna array operation. The results of numerical simulation confirmed that, in the first approximation, the problem of the antenna pattern controlling of a transmitter with a synthesized aperture based on the distribution of the complex wave amplitude measured in the plane of receivers is correct. It allows to create a system of adaptive antenna pattern correction for maximization of communication channel capacity.

    Keywords: communication channel, directional pattern, complex amplitude, synthesized aperture, angular spectrum method, adaptive control

  • Physico-mathematical modeling of multi-step technology processes of single-mode waveguide fabrication in glass K-8 by ion exchange technique

    Physico-mathematical modeling of multi-step processes of waveguide fabrication in glass K-8, based on the combined, solution of two-dimensional nonlinear diffusion equation, electrostatic equation and wave equation has been made. The diffusion equation was solved by application of implicit finite-difference two-layer Crank-Nicolson scheme with appropriate boundary conditions for each step of technology. The general case of three-step technological process is considered, including thermal ion exchange ”silver-sodium” in salt melt mixture AgNO3:NaNO3, electric field-assisted waveguide burial in salt melt NaNO3 and final step of glass substrate annealing. The technological conditions for the fabrication of single-mode waveguides, which have the size of mode field suitable for efficient butt coupling of waveguides with optical fibers at 1.55 micrometer wavelength, have been determined. The calculated mode size of waveguides is 10.6*9.5 um; the coupling efficiency with fiber is above 99%. Also the modeling of partially buried waveguide has been performed, where the field-assisted burial was made with the deposited mask covering the half-surface of ion-exchanged waveguide. Such waveguide has asymmetric distribution of refractive index and hybrid guided modes, and it may be the base of passive waveguide polarization TE-TM converters.

    Keywords: integrated optics, optical waveguides, ion exchange in glass, electrically stimulated migration of ions, the nonlinear diffusion equation, waveguide mode

  • Application of correlation functions for an assessment of an error of a form of details of cars in cross section

    Questions of use of the device of the correlation analysis for an assessment of an error of a form of details of cars in cross section are considered. It is shown that use of the considered device also effectively as well as application of traditional methods of an assessment of an error of a form, however demands smaller computing expenses

    Keywords: error, form, details, correlation, analysis

  • Circuit solutions of R-S-latch and D-trigger having nonvolatile electrically programmable memory

    In this work new circuit solutions of R-S-latch and D-trigger having nonvolatile electrically programmable memory and nonvolatile shift register are presented. It shows that nonvolatile R-S-latch can be effectively used as a memory cell and simultaneously as write and read circuits for it, thus it makes possible to increase reliability of read operation from EEPROM at the expense of differential read for every bit.

    Keywords: CMOS, R-S-latch, D-tirgger, shift register, EEPROM, nonvolatile memory

  • Sensitivity CMOS voltage reference to variations of the parameters of elements

    The article describes the preparation of the sensitivity of the output voltage for a typical architecture of voltage reference to variations of the parameters of elements. Also considers the main advantages of this approach in the analysis and design of circuits. The article presents the corresponding graphs sensitivities. Based on the findings conclusions about the impact of deviations of circuit elements on the output parameters of the reference voltage was done.

    Keywords: Sensitivity, CMOS voltage reference, bias voltage, group bias

  • The information base of textile materials and textures

    Information base of textile textures and materials, with the detailed description of the software for work with base is considered. It is told about methods of creation of base of textile textures and materials and about opportunities of the represented project.

    Keywords: informatsionnno base, textile industry, texture, materials, visualization, software, graphics

  • The automated base 3DDT of textile textures and materials

    The automated base 3DDT of textile textures and materials, with the detailed description of the software for work with base is considered. Market research of consumption of the represented project and program opportunities of alternative software products is carried out

    Keywords: automated base, textile industry, texture, materials, visualization, software, graphics, 3D

  • Methods of forming the information base of textile materials and textures

    The methods of forming information base of textile materials and textures, with a detailed description of the software for working with images. Describes the methods of creating the base of textile materials and textures.

    Keywords: informatsionnno base, textile industry, texture, materials, visualization, software, graphics, scanning, photography

  • The parametric method of determining a phase difference of quasi-harmonic signals

    The method of digital parametric measurement of the phase shift of signals with slowly varying amplitudes of the same slowly varying instantaneous frequencies was proposed. The numerical simulations and experiments on the developed hardware and software system were carried out. The error of measurement the phase difference of harmonic signals in the experiments were not more than  0,00001 radian. The method can be used in applications where the measured value is expressed in terms of the phase difference of quasi-harmonic signals.

    Keywords: quasi-harmonic signal, phase shift, real time measurements, hardware and software system