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  • Evaluation of the entropy of fragments of X-ray images of the lungs

    The emergence of digital X-ray machines and the development of cloud storage technology has led to the accumulation of a huge number of medical X-rays, in particular, chest x-rays - fluorography. The accumulated image bases after high-quality preprocessing can be used to train the deep convolutional neural networks that have received the most development in recent years, the trained network performs preliminary binary classification of the incoming flow of images and can be used as a radiologist assistant. For this purpose, it is necessary to adequately train the neural net-work to minimize errors of the first and second kind. A possible approach to improving the efficiency of neural networks, reducing the computational complexity and quality of image classification by the criteria is the use of auxiliary approaches of image preprocessing and preliminary entropy calculation. The article presents an algorithm for the X-ray image preprocessing, its division into fragments and the calculation of the entropy of individual fragments. During the preprocessing, the region of interest with lungs and the spine is selected from the entire image, constituting about 30-40% of the entire image, then the image is divided into a fragment matrix and the entropy of individual fragments is calculated using the Shannon formula, by analyzing individual pixels. By determining the frequency of each of the 255 colors, the total entropy is calculated. The use of entropy for detecting pathologies is based on the assumption of dif-ferences in its values for individual fragments and the overall picture of its distribution between images with the norm and pathologies. Statistical indicators are analyzed: standard deviation of error, variance.

    Keywords: image entropy, fragments, deep convolutional neural network, machine learning, x-rays images, computational experiment, matrix of elements, image preprocessing, statistical analysis, binary classification

  • Classification of directions of patenting in the field of industrial use of wood greens

    The purpose of this study is to perform a classification to form a knowledge base in the field of harvesting and use in industry and in the social sphere of one of the valuable types of non-wood forest resources-tree greens. Such knowledge base is necessary for synthesis of new progressive processes, machines and mechanisms for harvesting and use of wood greens. The basis of the classification formation is based on the analysis of technological and technical solutions based on scientific and technical search, given in inventions and utility models patented in 2010-2019 in the Russian Federation. As a result of researches the main directions of patenting of developments in the field of preparation and use of wood greens are classified.

    Keywords: modeling, wood density, logging, skidding, forwarder, skidder

  • The task of developing a demo-genetic model for the adaptation of pests to agricultural crops, taking into account the type of taxis

    The publication is devoted to the task of developing a demo-genetic model of the adaptation of pests to transgenic and hybrid agricultural crops, taking into account the type of taxis. An assumption is introduced that the dynamics of hybrid agricultural crops can be investigated using demo-genetic models. A description of the problem is given in accordance with the characteristics of the growth of biomass of agricultural crops and the dynamics of pests, as well as taxis species. The modeling of the processes of fast and slow taxis depending on the behavior of pests at a particular point in time is described in detail, taking into account the type of their genotypes that affect the acquisition of mutations. The paper describes the features of the physiological structure and life cycle of insect pests, affecting the prediction of their spatial concentration and, accordingly, the prediction of productivity; the possibilities of their application in mathematical modeling.

    Keywords: demo-genetic model, taxis, transgenic agriculture, hybrid, pest, biomass, diffusion

  • Mathematical modeling of the reliability of a solar hot water system in the Republic of Mari El

    The reliability of the solar heating system with solar collectors was studied using the logical-probabilistic method by building a fault tree. The fault tree was obtained by sequentially detailing the events associated with failures of the solar heating system, as well as its elements. Events were taken into account: conducting test diagnostics of elements of the power supply system, repairing failed elements, failure of elements, reducing the power of solar collectors due to a decrease in the intensity of the solar radiation. The events were divided into two groups: events in which there is sufficient intensity of solar radiation for the hot water supply from the solar collectors, as well as events when the heating supply cannot be provided only due to the solar collectors. The last group of events was divided into two subgroups, within events caused short-term downtimes (at the time of switching) and long-term downtimes (at the time of replacing or repairing a failed system element). Long shutdowns are associated with the coincidence of failures, repair or diagnosis of one or more elements of the solar heating system. Expressions are compiled to calculate the probability of long downtimes, the probability of short downtimes, the probability of failure due to a decrease in the intensity of the solar radiation, and the total probability of failures. As a result of substituting the values of the reliability indicators of the elements of the solar heating system, the value of the total probability of failure during the year is 4.03∙10-5.

    Keywords: solar hot water supply, reliability, solar collector, failure cause, reliability modeling

  • The calculation of the temperature of the evaporating layer drops

    To calculate the trajectory and coordinates of the droplets, the time of their flight, it is necessary to determine the parameters of droplet evaporation and their concentration in the stream. After the nozzle passes, the droplets move along different trajectories and form a fuel torch. The trajectory of the torch droplets is calculated according to the given initial parameters of the droplets, as well as the parameters of the nozzle and taking into account their influence on the movement of the droplet The aim of this work is to calculate the temperature of the evaporating droplet layer, which is necessary for calculating the trajectory and time of the droplet's motion depending on the thermodynamic parameters of the fuel. Based on the obtained air and fuel vapor parameters, the temperature of the evaporating droplet layer is found, which is necessary for calculating the trajectory, coordinates and time of movement of the fuel droplets after the nozzle.

    Keywords: fuel, centrifugal nozzle, atomization spectrum, trajectory, evaporation temperature

  • Comprehensive spatial data system Rail infrastructure

    The object of the research, the result of which is the presented work, is a comprehensive system of spatial data of the railway infrastructure, within which a high-precision system of coordinates of the Russian Railways has been created, and methods definition of normal heights in the Baltic Heights System 1977. The strategy and prospects for the development of high-speed transport highways (VSM) have been described. Methods for determining normal heights at research sites are given.

    Keywords: Global navigation satellite systems (GNSS), GLONASS, high-speed highway (Navy), high-precision coordinate system (WCC), altitude system, quasi-geoid

  • Estimation of the accuracy of direct methods for integrating equations of motion

    The article discusses the most common schemes of direct integration of equations of motion in engineering practice, and gives basic formulas. An analysis of the accuracy of these methods is made on the example of solving a test problem

    Keywords: structural dynamics, structural mechanics, direct methods for integrating equations of motion, Newmark's method, Habolt's method, Wilson's method

  • Synergetic control of energy converters in an electric vehicle system

    The article demonstrates the study of the processes of controlling the power system of an electric vehicle and the processes of energy distribution in it using pulse-width voltage converters. The general structure of the electric vehicle’s power system and elements of its subsystems are described. The pulse-width boost and buck DC-DC converters are considered. Based on the given mathematical model, the synthesis of controllers is carried out using the methods of the synergetic control theory. Mathematical modeling of the closed DC-DC converter control system, providing asymptotic stability and adaptability to parametric disturbances, is performed.

    Keywords: electric vehicle, pulse-width converters, control system, ADAR, synergetic control theory, integral adaptation

  • Development of a unified module with microprocessor control system for container pneumatic transport

    issues of optimization of the structure of the container pneumatic transport system are considered. The expediency of combining the functions of the equipment included in the transport system is shown. A functional diagram of a universal module that performs the functions of all blocks of a pneumatic transport system is presented. A block diagram of a microprocessor control system that provides the functioning of the mechanisms of a universal module is proposed.

    Keywords: microprocessor system, pneumatic transport system, transport container, stations of the transport system, control algorithm, structure of the transport system, transport pipeline

  • Analysis of the stress-strain state of the rotor shaft of a turbocharger with the installed repair sleeve

    The Minsk Motor Plant D-245 engines are the most widely used in automobiles and tractor manufacturing in Russia and neighboring countries. These engines are installed on cars of the GAZ and MAZ family, PAZ buses, special equipment manufactured by Amkodor, MTZ tractors, etc. A turbocharger is one of the engines units affects power and environmental performance. The presence of a large number of engines under consideration makes it important for repair enterprises to improve the technological process of repairing turbochargers. A large number of technologies for repair rotor shaft of the turbocharger have been developed to date. However, there is no technology to restore the outer surface of the rotor seal sleeve after they touch the hole of the middle housing. The article presents the results of calculating the stress-strain state of the rotor shaft of a turbocharger, taking into account the installation of an additional (repair) part as a turbine seal sleeve. The analysis of the created solid-state model was carried out using of the SolidWorks Simulation system. The calculation was carried out at various shaft diameters for bearings. The study found that the voltage in dangerous sections of the rotor shaft with the installed repair sleeve is higher than without it. However, they are much lower than the permissible torsional stresses. Therefore, the probability of destruction of the rotor shaft during normal operation of the turbocharger, due to the occurrence of a resonance phenomenon, even with the minimum allowable diameter, will be very small. The presented data allow the use of this repair method to restore the operability of the rotor shaft of the TKR-6 turbocharger.

    Keywords: engine, turbocharger, defect, repair technology, additional part, repair sleeve, stress-strain state, solid-state model, dangerous section, permissible stress

  • Numerical experiments on the scattering of warm fogs by artificial droplets

    Various methods are used to scatter warm fogs: direct combustion of fuel in the fog; electric heating of the fog; introduction of streams or jets of warm and dry air into the fog; use of radiant energy for direct evaporation of hydrometeors; using explosions of highly heat-forming substances, etc. [4]. In this paper, artificially sprayed water droplets are used to scatter warm fogs. Refined calculations were made to investigate the possibility of fog scattering by artificial droplets. The model describes the fall of drops of radius r2 through the fog, consisting of drops of radius r1, the concentration of which is equal to n1. Detailed equations of gravitational coagulation are used taking into account the hydrodynamic interaction of droplets. The temporal characteristics of fog scattering (increase in visibility range) depending on the size of artificial droplets and their concentration are investigated. The size of artificial drops and their concentration, at which the maximum effect on fog scattering is achieved, are determined.

    Keywords: scattering of warm fogs, meteorological visibility range, concentration of fog drops, fog water content, artificial influence on fog

  • Modeling the diffusion saturation with carbon of austenite doped with chromium

    "Prediction of carbon concentration profiles depending on the cementation parameters is possible using mathematical models, most of which show good results for austenite Fe-C, without affecting the influence of alloying substitution elements. The paper describes modeling using the finite element method of the diffusion saturation of the austenite of the Fe-C-Cr system with carbon during cementation using 15Cr steel as an example, taking into account the influence of temperature, and also provides practical confirmation of the model. For the numerical solution of the problem, the COMSOL Multiphysics program was used. It has been established that for the one-stage cementation mode, the applied model of carbon diffusion in undoped austenite is in good agreement with the experimental data for austenite of the Fe-C-Cr system of steel 15Cr. For a two-stage process, the calculation of carbon concentration in the surface layer has a slightly larger deviation from the experimental data than at a greater depth."

    Keywords: carbon diffusion, COMSOL, final method, carburization, cementation, steel, diffusion, mass transfer, alloyed austenite, modeling, elements

  • The use of various criteria in solving an inhomogeneous minimax problem

    The article deals with the solution of the inhomogeneous minimax problem using genetic algorithms, as well as using several variants of the Plotnikov-Zverev algorithm. Three types of criteria for setting the function of assessing the fitness of individuals are described. The efficiency of genetic algorithms is compared with the Plotnikov-Zverev algorithm, using different criteria of the fitness function of individuals. According to the results of the computational experiment, it was concluded that the use of the quadratic criterion for the modified Goldberg model, using a two-point crossover, increases the efficiency of the genetic algorithm, and the accuracy of this solution is higher compared to the solutions obtained using modifications of the Plotnikov-Zverev algorithm.

    Keywords: schedule theory, inhomogeneous minimax problem, modified Goldberg model, genetic algorithm, minimax criterion, quadratic criterion, minimax criterion, cubic criterion, Plotnikov-Zverev algorithm

  • Formalization of regulatory and system-wide requirements for the curriculum of a typical university

    In this work, the author has compiled a list of requirements and corresponding indicators that must be taken into account in the process of creating the university timetable and estimates of the significance of each of these indicators are obtained. The task is to formulate directly the timetable formation procedure on the basis of the list of indicators and assessments of their importance. It is supposed to consider the possibility of solving this problem based on the use of its formalized model. To form a model, it is first necessary to formalize all the requirements from their list. There is considered an example of some of these requirements that briefly describe the procedure for their formalization.

    Keywords: higher education institution, timetable, timetable requirements, formalization, initial data

  • Numerical experiments on the scattering of warm fogs by artificial droplets

    The paper presents the results of numerical estimates of scattering of a dispersed medium (fog) using thermal and dynamic devices. Numerical modeling methods were used to obtain the results. On the basis of calculations, the use of different classes of combustible substances (kerosene, etc.) was analyzed for thermal dispersion, which is based on heating the air-drop medium to a temperature above the dew point, so that the drops that make up the fog evaporated. Technical devices of various capacities for pumping air from the zone of illumination, that is, using the method of dynamic scattering, are considered. The dynamic method is based on creating a flow of dry air located above the dispersed medium layer. In this case, the drier air coming from above or from the side causes the particles of the dispersed medium to evaporate, which leads to a decrease in its density.

    Keywords: dispersed medium, low layered clouds, thermal scattering method, dynamic scattering method, calorific value of substances, zone of enlightenment

  • Simulation of the design activity diversification of innovative enterprise

    Based on the processing of radar information from the radar network of the North Caucasus storm broadcasting, a filtering technique was proposed using complex information from several meteor radars.

    Keywords: Radar, automation, refraction, identification, radar network

  • Analysis of functional completeness of health monitoring devices

    In today's world, health control is an essential element of everyday life. The article highlights the list of functional capabilities of various devices (smart watches, fitness bracelets) and describes the results of a formalized analysis of the functional completeness of health monitoring devices. On the example of two different sets of user requirements, two conditional systems are included in the study, by the degree of similarity with which it is possible to judge how the analyzed devices are suitable for this user.

    Keywords: Health monitoring devices, fitness bracelet, comparative analysis of functional completeness, pressure measurement, pulse, ECG, training monitoring, analysis of compliance with user requirements for devices, similarity of devices

  • Determination of the lower confidence limit for the hardness of a set of machine parts by the calculation method

    An algorithm for determining the lower confidence limit (NDH) for the minimum value of the hardness of a set of machine parts by calculation is developed. For processing of statistical data of the hardness measurements used a three-parameter Weibull distribution is offered. The transition from sample data to population data is carried out by the graphical method. According to the algorithm, NDH was found for the minimum hardness value with confidence probabilities p=0.9; 0.92;0.93;0.94.

    Keywords: hardness, machine parts, sampling, aggregate, lower confidence limit, graphic method, calculation method

  • Study of the heat transfer process in a liquid cooling system of a computer based on ferrofluids

    In this research the research problem of the liquid cooling system of supercomputer processors on nanomagnetic liquids by numerical modeling and the pilot study of processes of heat convection in the studied object is set. In article results of numerical modeling and the pilot study of process of the heat transfer are given in the heat exchanger of the liquid cooling system of supercomputer processors on the basis of nanomagnetic liquids, or ferroflyuid at influence of magnetic field impact assessment of magnetic field on the thermal resistance of the system and coefficient of heat convection the wall liquid Is made at different strengths of magnetic field. The numerical model of process of the heat transfer in the system the processor heat exchanger was investigated.

    Keywords: processor, thermal resistance, Laplace equation, liquid computer cooling system, ferrofluid, nanomagnetic liquid, heat transfer, heat transfer coefficient

  • About increasing the availability of the default gateway in corporate networks

    Considered an important component of corporate networks - the default gateway. The main objective of the project is to minimize the time of convergence by ensuring high availability in order to ensure the continuity of the head office connection to remote offices. An analysis is made of the operation of one of the technological solutions, as well as estimates of the probability of failure-free operation for the default gateway with redundancy and without.

    Keywords: HSRP, fault tolerance, high availability, failure, convergence, routing, protocol, load reserve, redundancy, business continuity

  • Emotional attitudes of the students of Grozny: affective component

    The paper presents the results of measuring the overall emotional state of students in Grozny at the beginning of 2016. This characteristic is one of the indicators of social health of the study group, in particular, in relation to the political field. It is based on a pilot survey conducted among 141 students of the Grozny state oil technical University. By gender and national composition, the sample was approximately the same as in the entire educational institution. To measure the affective component of the emotional state, the method of the semantic differential of CH. Osgood was used. The interpretation of the results obtained was based on the Coombs ideal point theory, based on the proximity in the semantic space of the image of a real object from the images of ideal constructs. The distribution functions of the affective level of the emotional state are calculated in a linear approximation, as well as in the framework of the previously developed stochastic nonlinear psychosemantic phenomenological model. It was found that 14 % of respondents are characterized by a neutral emotional state, and 55% - positive. Of these, 33% reported their condition as slightly positive (a level of 0.1 to 0.3 on a scale of -1 to +1), and 22 % reported a steady positive (a level of 0.4 to 1). Negative emotional state was observed in 31 % of the respondents, of which 20 % - slightly negative (level from -0.1 to -0.3), and 11 % - stable negative (level -0.4 and below). The latter are the subgroup of risk in which social and political tensions can develop. The core of this subgroup is formed by 5 % of respondents who showed an extremely negative emotional state, with a level of -1. The results obtained differ slightly from similar data measured among students in Rostov-on-don around the same time period. For students of Grozny, the group of respondents with a positive emotional state is 10% more than for Rostov residents.

    Keywords: social attitudes, affective component, semantic differential, Coombs perception theory, linear approximation, distribution function, nonlinear stochastic model, risk group, social tension

  • Technical science. Building and architecture

  • Research of properties and characteristics of foam glass broken stone application in road constructions

    This article describes the territories of the northern regions of the Russian Federation, the problems of the distribution of permafrost soils (MMG), and discusses the difficulties encountered in the construction of roads in difficult geocryological conditions. The introduction of heat-insulating layers of foam glass rubble into the design of pavement is proposed. The basic physical and technical characteristics have been analyzed, and the key properties of foam glass rubble are determined. The article describes the process of production of foam glass, the advantages that allow the use of this material in various fields of construction. Typical road structures made of soil are considered. A comparison is made of a typical construction of pavement made traditionally from soil (high embankment) with a construction with a heat-insulating layer of foam-glass rubble. The advantages have been listed when using structures using foam glass rubble in road construction.

    Keywords: foam-glass rubble, road construction, automobile road, heat-insulating layer, frost, north, glass, construction, soil, materia

  • Investigation of cylindrical mesh shell with increased stiffness of supporting ribs

    The work of a metal cylindrical mesh shell with support ribs of increased rigidity is investigated. The rational variant of the profile of longitudinal elements is determined and the recommended parameters of the cross-section of the rods in the place of strengthening of the lower faces are proposed. Several approaches to circuit design were tested and cross-sections were calculated for three blocks of design solutions. It is recommended to use the I-beam profile as the optimal option to increase the coefficient of stability of the structure. Due to the increased rigidity of the support ribs, a significant unloading of dangerous areas was obtained and the form of possible deformation of the system was reconstructed. Qualitative regularities of distribution of longitudinal forces and displacements reflecting positive changes of the general state of the grid surface are revealed. The obtained numerical values of the calculated parameters showed the presence of reserves of the bearing capacity of the structure.

    Keywords: cylindrical mesh shell, roof, reinforcement, stiffness of supporting ribs, force factor, deformation parameter

  • Dependence of frost resistance of fine-grained concrete modified by polymers on the ratio of conditionally closed and open capillary porosity

    GOST 10060-2012 as the main criterion of frost resistance for all concretes, including fine-grained, established the ratio of the compressive strength of the main and control samples is not less than 0.9, taking into account the coefficient of variation of strength in the series. There are numerous studies in which the dependence of the frost resistance of concrete on the nature of its porosity is revealed, and the criteria of frost resistance in the form of, for example, the ratio of open and conditionally closed porosity are proposed. The article examines the impact of indicators of porosity on frost resistance of mortar (fine aggregate concrete), the basic criterion GOST 10060-2012, and also for frost resistance of the contact zone according to GOST 31357 - one of the normalized indicators of quality of solutions and fine-grained concrete obtained from dry mixes. The purpose of this study is to identify the dependence of changes in the compression and bending strengths, as well as changes in adhesion to the base of polymer-modified fine-grained concrete on the nature of porosity. The frost resistance of 36 compositions obtained using three different Portland cements and three redispersible polymer powders with a dosage from 0 to 3% by weight of the dry mixture was studied. In addition to polymers, low-modulus inclusions in the form of ash microsphere or entrained air are introduced into a number of compositions. The main samples were tested after 75 freeze-thaw cycles according to GOST 31357.

    Keywords: dry mixes, frost resistance of the contact zone, open porosity, adhesion to the base