The article describes an approach to the operation of a data transmission network protection system against computer attacks based on a hybrid neural network. It is proposed to use a hybrid neural network as a machine learning method. To calculate the output value of neural network signals, the activation function is used. The neural network model consists of recurrent cells - LSTM and GRU. Experiments have demonstrated that the proposed network protection system for detecting computer attacks based on an assessment of the self-similarity of the system functioning parameters using fractal indicators and predicting the impact of cyber attacks by applying the proposed structure of the LSTM neural network has a sufficiently high efficiency in detecting both known and unknown spacecraft. The probability of detecting known spacecraft is 0.96, and the zero-day attack is 0.8.
Keywords: data transmission network, computer attack, neural network, protection system, network traffic, auto-encoder, accuracy, completeness, detection, classifier, self-similarity, recurrent cells with long short-term memory
The article contains an analysis of the shallow elastic spherical shell on a rectangular plan, reinforced with ribs along its contour, under the uniformly distributed load. The problem is solved numerically with the variational-difference method, considering the geometric nonlineaity and the shear deformations of the shell and the ribs. As a result, the dependencies of the critical load on the shell stiffness and the ribs stiffness are obtained.
Keywords: shallow spherical shell, ribbed shell, stability, bending stiffness, geometrical nonlinearity, variational-difference method, critical load
The article analyzes the technical condition and reliability of heat supply networks. When using the calculation and assessment of the overall reliability of pipelines and sources of heat supply. Substantiates the requirements for the reconstruction of regular pipelines.
Keywords: heat supply, reliability of the heat supply system, hydraulic calculation, reliability coefficient, dilapidation of the heat supply network
A survey of the frame-panel building was carried out, in which ecowool was used as the heat-insulating material. A study was made of the moisture state of wooden frame walls and attic floors. Ecowool samples were taken from various sections of the wall. No mold was detected on material samples. In this case, the sorption humidity was not more than 16%. The results of laboratory tests of ecowool showed high persistence of density and coefficient of thermal conductivity during long-term operation. Tests were conducted to determine the effect of moisture on the change in the physical and technical properties of ecowool. The research results were processed by statistical methods. As a result of the study, it was found that moisture does not accumulate in the ecowool layer of the examined frame walls and attic flooring, but goes out through the insulation and elements of the building envelope. The conducted studies allow us to predict the preservation of the heat-shielding properties of ecowool during operation for a long time
Keywords: ecowool, durability, sorption humidity, density, coefficient of thermal conductivity
The article discusses the causes of the emergence of digital noise in video sequence images. It is proposed to evaluate the effectiveness of noise suppression methods by measuring the peak signal-to-noise ratio. A method is proposed for preliminary improvement of the quality of images in a video sequence for further processing in order to search and recognize objects on a complex background. The originality of the method consists in using the analysis of the contribution coefficient of single images in a video sequence. The results of experiments with images from the USC-SIPI database are presented. The results obtained are not inferior to their counterparts, and surpass them in some indicators.
Keywords: video sequence processing, video enhancement, object recognition on a complex background
The article presents an analysis of promising research on the formation of vibrational mechanochemical coatings from the point of view of practical use in the real sector of the economy
Keywords: combined methods of treatment, vibration treatment, the vibration mechano-chemical (chemical-mechanical) coverage webrevolve technological system, mechanical coating, fragmentary nature, plastic deformation, uniform coating, vibrowave impact, microstructu
This article discusses the process of developing an ultrasonic method of measuring the state of the electrolyte in the process of burning discharge with an electric electrode. The classical methods of electrical effects on the surface of steels, such as electrochemical, electro-erosion, electro-thermal and electro-mechanical have their drawbacks. Namely, high energy consumption, environmental pollution, the problem of recycling by-products, the difficulty of obtaining the required surface profile to a certain extent. In this regard, there is an acute issue of the development and research of new energy-saving, environmentally friendly and cost-effective methods of impact on the surface. At the moment there are no systematic experimental studies of discharge in multiphase media. Not the conditions for the ignition of the discharge with an electrolytic cathode. Not studied physical processes on the boundary of the plasma and the liquid. There is no mechanism of the effect of discharge in the vapor-gas bubble on the surface of metals. All the above reasons delay the development of technology of plasma-electrolyte formation of the surface microrelief. The aim of the work is to measure and optimize the ultrasonic signal and calculate the frequency spectrum of reflected ultrasonic vibrations from a large number of reflectors (electrolyte bubbles), as well as the development of mathematical modeling of the process of reflection of ultrasound from the electrolyte bubbles.
Keywords: Ultrasound; technique; electrolyte; combustion; measurement
The absorbing apparatus serves to extinguish the impact when the wagons cohere and move. Most of the energy, about 80%, in this system is absorbed by a friction unit consisting of a friction wedge and a fixed plate. Absorption of energy in this system occurs due to the work of frictional forces arising during longitudinal motion of the pressure wedge with respect to the friction plate. Due to the large shock-frictional loads, intensive wear and destruction of the cermet cake occurs, which adversely affects the energy capacity of the absorbing apparatus. To eliminate these shortcomings, studies were conducted to create a new material. After numerous experiments, a composition was obtained with the optimum content of components, which maximally satisfies the working conditions of the friction unit and the requirements imposed on these devices.
Keywords: absorbing apparatus, friction unit, cermet, wear resistance, friction plate, powder material, sintering technology
The article discusses the technological capabilities of application of vibratory mechanical hard lubricant coatings on the basis of MоS2 to improve the surface quality and operational properties of parts made of aluminum with an oxide coating.
Keywords: vibration treatment, the vibration mechano-chemical coating of solid lubricant, combined methods of treatment
The article considers the device for experimental and laboratory testing of microclimate systems. The device is an experimental setup in which it is possible to study the microclimate parameters of multi-functional and multi-level buildings by modeling various processes and their location in the total volume of buildings. Accordingly, with the help of this test model, the parameters of the movement of contaminated air masses and convective flows are studied.
Keywords: test model, installation, microclimate, multi-functional multi-level buildings, process modeling, air, convective flows
One of the most important advantages of the ion lasers based on the ion transitions of metal vapors and noble gases, is the high quality of radiation (high monochromaticity and coherence). However oscillation on each of active media takes place on restricted number of laser transitions. The purpose of this work is receiving a laser radiation at the same time on several quantum transitions in the wide range of wavelengths when using mix of several active mediums. That increases a set of the laser lines radiated by one laser. The characteristics of ion laser transitions (gain, power, noise level) are substantially improved if a hollow cathode transverse-type discharge is used for pumping of the laser transition, and such method of a pumping was used in this work. It was experimentally found the discharge conditions providing various ratio of laser output power on various laser lines for laser on mixture of helium with cadmium and mercury vapors in which the population inversion and laser oscillation are carried out on mercury ion transition with the wavelengths of 615nm (red), and on cadmium ion transitions with the wavelength of 533,7&537,8nm (green) and 441,6nm (blue), and also for laser on mixture of helium with mercury vapors and krypton which lasing on 431,8nm and 469,4nm blue-green krypton ion lines and 615nm red and 794,5 nm IR mercury ion lines. The studied lasers can be useful at information processing, in a metrology, etc.
Keywords: ion metal vapor laser, hollow cathode discharge, the combined active media
Numerical solution to the problem of heat transfer in boundary layers transparent Strip on the walls, exposed on the opposite side of the radiant-convective heating. Study of influence of mode parameters on heat transfer process of tasks carried out in the case of the gradient flow and included the most typical variants of transportation processes. The purpose of the real work is studying of processes of transfer at non-linear boundary conditions, obtaining approximate and analytical decisions non-linear warm and a mass transfer, establishment of communication between regime parameters and physical interpretation of results of a research. Also some conjugate problems of heat exchange in the presence of radiation are studied. The analysis received decisions is carried out. The executed research allowed to establish that existence of a transversal overflow of heat in a wall and also the radiation of a surface have significant effect on the nature of distribution of the surface temperatures.
Keywords: boundary layer, convection, radiation, gradient flow, conjugate heat transfer
The project for creation of the first in Russia Engineering Forum of scientific and technological activities, social and technological entrepreneurship “Rozmysly” is presented, this forum develops the principles of an open public interdisciplinary electronic environment. The substantiation of the social significance of the project is given. The new project implies involving an even wider range of practitioners, research engineers, young scientists, applicants, graduate students, students and even senior pupils in scientific engineering knowledge by providing them with the opportunity to publish, read and discuss the results of promising research and development works, engineering solutions, inventions and rationalization or innovative proposals in the form of an electronic preprint. Conceptually, the project represents a new culture of scientific publications based on global and mini Internet platforms. It is shown that the basic advantage is achieved through the implementation of an open access initiative. From the date of publication, the material is available for the widest possible range of readers. The project is a kind of an interdisciplinary scientific and technological engineering forum.
Keywords: site, Internet platform, engineering forum and storage, open access, preprint, foresight
Numerical solution of the problem of heat transfer in the boundary layers of transparent gas wall, exposed on the opposite side of radiant-convective heating. The energy dissipation due to viscosity is negligible, the wall is thermally thin, and the physical properties of the medium do not depend on temperature. The aim of this work - finding the local heat transfer coefficients (Nusselt number) needed for the analysis of heat exchangers. When solving the problem of nonlinear transfer functions linearizing method is used, based on which numerical scheme for computer calculations was constructed. The intensity of the local heat transfer in the boundary layer is determined by the number Kx = Nux / Nux0, where the value Nusselt numbers refer to the conditions under consideration of the problem of heat exchange (Nux) and constant surface temperature (Nux0). From a physical point of view, non-dimensional parameter Kx is a measure of the intensity of heat transfer in the boundary layer on a nonisothermal surface compared to heat transfer when the wall temperature everywhere the same. The analysis of this research showed that in radiative-convective heating number Kx on the front edge of the plate takes the largest value of Kx ≈ 1,37 corresponding to a constant heat flux on the wall. It is also shown that the relative temperature of the incoming flow has a significant impact on the value of Kx. The effect of this setting is especially evident in the processes when dominated by the effect of radiation and related to the nonlinearity of the transfer processes. The analysis revealed the influence of basic parameters of heat transfer on the development of transport processes in the boundary layer by heating radiation and convection simultaneously.
Keywords: Boundary layer, convection, radiation, radiation-convection heating, high temperature gas invironment, linearizing function
The article describes one of the methods of machining deep grooves in the turbine rotor disk mill, analyzed the parameters of the shear layer, defined modes of processing and the main process time.
Keywords: milling techniques, the parameters of the shear layer, the maximum thickness of the cut, the cutting conditions, the cutting force, the main production processing time