bluuebunny/crossref_metadata_2025 huggingface dataset:
Development of a technological processes registration system based on CCD cameras for tasks of industrial laser beam machining of materials
Authors: Chkalova D G
Published: November 2020

The use of CCD cameras for construction of systems for automated control of laser beam machining technological processes is an urgent task due to low cost of the equipment used and high information content of the resulting graphic data. The main goal of the study is to achieve the maximum information content of the working area image of the tool by ensuring its highest contrast by selecting the optimal relative position of the system components. As a result of the experiments, it was found that the most effective configuration of video recording system is lateral position of camera and illumination, opposed the movement direction of laser head. The methodology for comparing the contrast of obtained images from CCD cameras for various configurations in order to mathematically evaluate their applicability for automated processing tasks is proposed.
Modeling heat transfer processes in heating systems for surface of highways
Authors: Kamenchukov A V , Tyan V D , Voinash SA , Ariko S Ye , Teterina I A , Sokolova V A , Rzhavtsev A A
Published: November 2020

At present, icing of the road surface has a significant impact on traffic safety, which reduces the coefficient of adhesion of tires by 5–10 times. In order to reduce this negative effect in winter, frictional, chemical, physical-chemical and combined methods of struggle are used. In this case, one of the most promising ways to combat icing is to use a hydraulic system for snow melting. This is due to the possibility of laying not only individual systems of snow melting under the road surface, but also urban heat communications on road sections subject to frequent ice formation. In this regard, the modeling of heat transfer processes in heating systems for road surfaces is relevant. The proposed mathematical description, as well as its implementation in the Abaqus software package based on finite element calculations, makes it possible to determine the temperature on the surface of the highways taking into account the coolant supply, the location of pipes, their diameter and depth, air convection temperature and a number of other parameters. In this regard, the developed simulation model of the hydraulic system for heating the surface of highways will be widely used in the reconstruction of road surfaces, as well as for the optimization of heating network laying systems.
Power distribution mechanism for the transmission of forest tracked and wheeled vehicles
Authors: Dobretsov R Y , Voinash S A , Sokolova V A , Krivonogova A S , Pushkov Yu L , Andronov A V
Published: November 2020

The article schematically considers a proposal for development and application of a controlled power distribution mechanism for machines involved in timber industry and agriculture. Use of the mechanism will increase energy efficiency of skidder and forwarder on tractor chassis, improve steering quality of tracked vehicles and improve controllability of wheeled vehicles. For articulated vehicles, use of a controlled power distribution mechanism is expected to reduce stresses on swing mechanism. The article presents analysis results of literary sources on problem of using controlled power distribution mechanisms in transmissions of tracked and wheeled vehicles. Advantages of using such mechanisms in transmissions of tractors and forest vehicles on their chassis are shown. References are given to publications containing descriptions of mechanisms that are similar in characteristics to the developed one and known methods for determining main parameters of power distribution mechanisms, approaches to kinematic, force analysis and energy balance construction of such mechanisms. Kinematic diagram of a new controlled mechanism of power distribution is considered, main parameters, control technologies, and areas of its application are determined. Links between the project and currently developed capabilities of Russian production are outlined. Development prospects of technology for controlling distribution of power in transmissions of tracked and wheeled vehicles in the field of transport engineering are indicated. A reference is given to the research complex created and used at the Peter the Great St. Petersburg Polytechnic University, as allowing to conduct comprehensive tests of experimental models of transmissions of transport and traction vehicles.
The effect of microwave heating of fruit and vegetable raw materials on the water-soluble antioxidants content
Authors: Perfilova Olga V , Babushkin Vadim A , Bryksina Kristina V
Published: November 2020

In the food industry, when processing fruits and vegetables, heat treatment is used. Most often, the pretreatment processing of plant materials is carried out with steam or water, as a result of which there is a loss of nutrients valuable for the human body, including antioxidants. The article proves the advantage of using microwave heating as a preliminary heat treatment of apple and beet refuse in order to increase nutritional value by increasing the content of water-soluble antioxidants in them. Thus, the content of vitamin C increases by 1.32 - 1.57 times, flavonoids by 1.77 - 2.01 times.
Modeling of friction engagement in a joint with carbon-carbon composite bushings in the atmosphere of Venus
Authors: Alisin V V , Roshchin M N , Markachev N A , Bogachev V A
Published: November 2020

The issues of the friction engagement of a carbon-carbon composite with steel under conditions of temperature and composition of the atmosphere of the planet Venus are studied in the article. The statement on the admissibility of using a carbon-carbon composite in friction units in an open atmosphere is substantiated. Antifriction properties of a carbon-carbon composite are investigated for friction against steel in the speed range 0.05 - 0.25 m / s and a contact pressure of 1 MPa. Tribological tests were carried out in sliding conditions according to the pin-on-disk scheme on a high-temperature test bench with a temperature range of 300-600 ° C. It has been shown experimentally that for given parameters of friction, there is no seizure of surfaces. Based on the study, it was found that the average value of the friction coefficient is 0.25, and the experimental data spread is less than 20%.
Assessment of the stress-strain state of a cable with parallel-laid conductive cores under bending deformations
Authors: Ismailov G M , Nizhegorodov A I , Lomovskaya S A , Sarkisov Yu S , Gorlenko N P
Published: November 2020

The paper considers the stress-strain state of a cable with parallel-laid conductive cores, taking into account the operating conditions. With the help of the Ansys program, the tribological interaction of parallel laid cable elements is modeled, the contact stresses between the elements are determined. Assessment of the stress-strain state of a cable with parallel-laid conductive cores will make it possible to assess the strength of the cable construction materials. These results can be used for twisted cables in design to improve their reliability.
Estimation of gas exchange parameters in the engine by numerical simulation
Authors: Zholobov L A , Medvedev A V , Pasin A V , Novozhilov A I
Published: November 2020

The article is devoted to mathematical modeling of gas exchange processes. The features of modeling gas exchange processes based on gas dynamics equations are shown. The parameters of the gas flow are calculated by three conservation laws obtained by applying the general laws of physics to the elementary mass released in the flow, followed by a transition to the limit when the volume occupied by this mass tends to zero: momentum, mass, and energy. A mathematical model of the working process in the engine cylinder is created by the necessary conditions for calculating the entire gas exchange. Using a computer allows for a more accurate and complete description of all the main features. In the foreground is not the complexity and volume of calculations, but the accuracy of approximating the processes of fresh charge entering the engine cylinders, the air flow in the intake tract, the possibility of a comprehensive study of the effect on the filling process of each of the parameters of the intake tract design and gas distribution, and the features of the engine operation mode under study. Filling dynamic phenomena in the intake system has the main goal of optimizing engine design parameters.
Mathematical models and solution of problems of the transfer theory in technical systems based on the problem of filtration of the Poisson process
Authors: Firsov A N , Sorokina N V
Published: November 2020

In this paper the problem of the filtration of a Poisson random process is solved. The theory of filtration has a rich history, but in recent decades it has taken an important place in the framework of cybernetics and engineering. The requirements of modern production and the implementation of complex control and communication systems determine the development of filtration theory methods. Much attention is paid to the formal mathematical aspects of the problem. An analytical solution of the filtration problem is constructed by the authors of the paper, the suggested approach helps to reduce the solution of the problem to the solution of a system of ordinary differential equations of the first order, and the solutions of differential equations give the desired quantities. Thus, the method for solving the problem of filtration is simplified. The proposed approach can be used in the complex engineering systems’ management, for example, when proceeding data from different sensors.
Stress-deformed state of the apparatus taking into account the influence of the location of mechanical damage in the zone of corrosive wear
Authors: Rubtsov A V , Kulakov P A , Arkhipova K S , Zakirnichny E G
Published: November 2020

Technological apparatuses of oil and gas refinery and petrochemical industries are the most responsible operational units, since they are used to carry out various technological processes in a continuous mode under the influence of high pressures, temperatures and aggressive working mediums. Due to the design features of the devices, corrosive wear can be both uniform and uneven, as well as concentrate in the areas most prone to corrosion damage. Various scenarios of corrosion damage and different zones of corrosion of constructional elements of the apparatus during operation can radically change the stress-deformed state, worsening the forecast and bringing the apparatus closer to the limiting state. Also, possible negative consequences on the device can be caused by mechanical damage - “risks” that are formed during mounting, repair or during transportation to the installation site. The mutual influence of the most unfavorable zones of corrosion damage to the apparatus and the presence of “marks” in these zones under the influence of operating loads can contribute to the development of the most negative variant of the development of an emergency situation. Currently, work on modeling the stress-deformed state of devices with different levels of accumulated damage, identifying the most loaded areas and the most unfavorable possible outcomes is relevant. This paper investigates the interconnection between the impact on the stress-deformed state of an apparatus with a “shirt” of operational loads, corrosion damage and the presence in this zone of a mechanical defect of the “risk” type with its various locations.
Modeling frequency integrating unfolding converter operation taking into account technological variation in parameters
Authors: Volkov Vadim S , Konkina Maria S
Published: November 2020

The article considers issues for taking into account technological variation in parameters for a bridge circuit of a frequency integrating unfolding converter containing semiconductor strain gauges at high temperature, using the Mathcad software as simulation environment. An analysis of the influence of technological variation in parameters has revealed the emergence of the initial imbalance of the bridge circuit, which is equivalent to the presence of a non-zero input signal, i.e. the pulse repetition frequency error, which is present at the output of frequency integrating unfolding converter at high temperature. A mathematical model for taking into account technological variation in parameters of a frequency integrating unfolding converter based on a semiconductor strain gauge bridge is proposed, which allows calculating the corresponding error. As a result, the above mentioned can be used in the development of additional methods and means for temperature compensation, taking into account features of semiconductor strain gauges, and to increase objectivity in the analysis of calculation results applied to converters of mechanical values into frequency.
Wear resistance of blade and disc working bodies of tillage tilling machines hardened by electrodes T-series
Authors: Rogovskii I L , Borak K V , Maksimovich E Yu , Smelik V A , Voinash S A , Maksimovich K Yu , Sokolova V A
Published: November 2020

Based on a systematic analysis of methods to increase the durability and wear resistance of the working bodies of tillage machines, it is established that their increase in 90% of cases is achieved by technological methods. In turn, this requires the use of expensive reinforcing materials, which leads to an increase in the cost of the final product. The solution of such a complex problem cannot be based on the use of one group of methods, but requires an integrated approach using a range of available groups of methods. Accordingly, the purpose of the work is to determine experimentally possible methods to increase the durability and wear resistance of the working bodies of tillage machines, taking into account the soil and climatic conditions of their operation. In the work, on the basis of soil-climatic conditions of operation of working bodies of tillage machines, operational, constructive and technological methods of increase of wear resistance of ploughshare and disk working bodies are experimentally established. Wear of the working bodies of tillage machines is complex. The problem of increasing the wear resistance and durability of working bodies that interact with the soil environment cannot be solved by using only technological methods to increase wear resistance and durability.
Ore particles segmentation using deep learning methods
Authors: Suprunenko V V
Published: November 2020

The feed size distribution of AG/SAG mills has a big impact on the efficiency of the whole beneficiation process. In this situation is very useful instrument could be a system for estimate size distribution of ore. In this paper method for ore segmentation was developed based on deep learning algorithm and digital image processing. First U-net network was trained on manually labelled images. Then trained network used for extracting particles area and watershed used for obtain final segmentation.
Machine for carrying out work on deep soiling with the simultaneous application of liquid organic fertilizers
Authors: Martynova N B , Bondareva G I , Toygambaev S K , Telovov N K
Published: November 2020

The necessity of carrying out work on deep loosening in lands newly introduced into agricultural circulation in soils of heavy mechanical composition, as well as destruction of the subsoil on old arable lands have been analyzed. Requirements for the work on deep loosening of the soil are grounded. The existing designs of reclamation rippers are considered and a passive two-row subsoiler with front shanks of a volumetric structure and rear curved shanks with additional plowshares is selected. The possibility of combining work on deep loosening and application of organic fertilizers to increase soil fertility, water and air permeability, and create the most favorable soil conditions for plant growth and development has been investigated. The existing rates of fertilization have been analyzed and the possibility of delivering an organic liquid to the enlarged pore space formed after soil loosening has been investigated. The influence of the ongoing agro-reclamation measures on increasing soil fertility, creating an optimal water and air balance for the growth and development of agricultural crops and the expected increase in yield are analyzed.
Analysis of the process of shaping the blanks of the GTE turbine working blades
Authors: Vdovin R A
Published: November 2020

The article provides a detailed analysis of the existing technological process of shaping the rotor blades of gas turbine engines. The main technological operations of the control of the airfoil airfoil are considered, possible reasons for the occurrence of the deviation of the theoretical airfoil of the blade from its real position are given. On the basis of the studies carried out, it was found that for “conditionally defective” blanks of GTE turbine rotor blades, which have insufficient allowance for the polishing operation, by reorienting the blank in space due to the refinement of technological bases, it is possible to achieve a relatively uniform distribution of the allowance and, as a consequence, to transfer them in the category of suitable ones.
Research of adhesive dosing possibility of glued laminated lumber technology
Authors: Razinkov E
Published: November 2020

Since the glue is not an ideal liquid for which the laws of its expiration are generally known, the purpose of our work was to determine the duration and speed of the resin outflow from the container, depending on 2 factors - the height of the container with the resin above the surface on which the resin is applied, and the conditional viscosity of the resin within its working value. As a result of the conducted research, it was found that it is possible to dose the glue in the glued beam technology, when using low-viscosity resins, by lifting the container with the resin (glue) above the level of the surface on which it is applied. Moreover, for low viscosity fluids with a viscosity up to 80 °C (on the examples of water and resin low viscosity) observed increase in flow rate from the container increasing the height of the rise of liquids over the surface to which it is applied. As the resin viscosity increases from 80 to 131s the absolute value of the resin flow rate from the container decreases.
Carbon-based materials in friction units at high temperatures
Authors: Roshchin M N , Krivosheev A Yu , Mishanova V G
Published: November 2020

The issues of the friction engagement of a carbon-carbon composites with steel at high temperatures are studied in the article. The statement on the admissibility of using a carbon composite in friction units at high temperatures is substantiated. Antifriction properties of carbon composite are investigated for friction against steel in the speed range 0.05 - 0.25 m / s and contact pressure 0.3…1 MPa. It has been shown experimentally that the “Hardcarb-T” material has better antifriction properties than the “Argalon-2D” material in the temperature range of + 300 … + 700 ° C and a velocity of 0.16 m / s. The coefficient of friction of the “Hardcarb-T” material in the temperature range 300 … 700 ° C varies from 0.28 to 0.38. With a load of 1.0 MPa and a sliding speed of 0.16 m / s, the friction coefficient of the “Argalon-2D” material is 38% higher than that of the “Hardcarb-T” material.
Ways of improving performance of mobile bricklaying robotic systems
Authors: Malakhov A V , Shutin D V , Marfin K V
Published: November 2020

To integrate innovations into practice, their effectiveness is of critical importance, especially when compared to previous generation technologies. The article discusses the two main aspects of the effectiveness of mobile bricklaying robots, as a technical system on one hand, and as a technology for organizing construction production on another. Efficiency of operation of automated building systems should be considered on the basis of synergistic analysis of these two factors. Study of feasibility of using such systems in organization of construction production is carried out taking into account the construction technology and the principles of construction organization. The efficiency of a robot as a technical system is assessed based on the efficiency of its use of energy and working time. The use of digital drives and optimization of design and algorithmic solutions are considered as means of increasing the energy efficiency of mobile bricklaying robots. A more complete use of working time is also proposed to be achieved through a combination of design and algorithmic solutions and the organization of the movement of material assets at a construction site.
Computer aided engineering design in the development of agricultural implements: a case study for a DPFA
Authors: Patuk Iaroslav , Borowski Piotr F
Published: November 2020

Nowadays, available engineering technologies allow the engineering industry to utilize software with numerical methods to generate optimal designs and solve complex issues in a wide range of tasks. Thus, this method plays a specific purpose for researchers, especially in agriculture, to improve designs which use materials excessively, and develop the geometry of implements optimally. This study focused on optimizing a deep placement fertilizer applicator by way of computer aided engineering. The finite element method simulation was also used to obtain optimum geometric parameters of the deep placement fertilizer applicator by topology optimization. The topology optimization generated a structural shape on the deep placement fertilizer applicator framework body to reduce excessive mass (weight), and propose a new shape for this type of implement. The simulation also reported the total material mass used under static load distribution in the deep placement fertilizer applicator framework. According to the study results, the total mass of the current deep placement fertilizer applicator design could be reduced by approximately 40% under present boundary conditions. The study results provide technical support in the development of agricultural implementation with the proposed design for further practical testability.
Smoothing of the airfoil section having curvature graph oscillations
Authors: Yerokhin A P
Published: November 2020

The article is devoted to the smoothing of the tabulated curves describing the aerodynamic profiles. In the course of the iterative process of changing the geometric characteristics of the airfoil when designing the wing surface, its smoothness may be disturbed. This necessitates smoothing the profile by deviating from some preset points. The paper deals with the issues of ensuring the convexity of the section of the profile, on which the graph of its curvature has oscillations. A smoothing procedure is described based on smoothness criteria obtained from the necessary and sufficient conditions for the existence of a polynomial of the eighth degree. The results of profile smoothing are presented, which confirm the effectiveness of the developed procedure for ensuring the convexity of the smooth curve.
Approaches review and tools analysis for thermal processes modeling in electron beam welding
Authors: Milov A V , Tynchenko V S , Kurashkin S O , Petrenko V E
Published: November 2020

The article is devoted to a review of approaches used to simulate thermal processes occurring during electron beam welding of thin-walled products. The analysis of more than fifty sources is carried out on the basis of which ideas about the current state of the problem considered in the article are formed. To implement the simulation, it is possible to use modern software systems such as: ANSYS, Comsol Multiphysics, Abaqus and NX Nastran, each of which has its own set of advantages and disadvantages. By using the method of expert evaluation on the basis of the formulated criteria, the most effective software was selected. The results of the study of mathematical models implemented in the selected software system will allow not only to get an idea of the thermal process occurring during electron beam welding of thin-walled products, as such, but also to form a mathematical justification for making technological and control decisions.
Local and centralized conditioning systems
Authors: Alhatem Ali
Published: November 2020

This article discusses two main types of air conditioning systems in office buildings: local and centralized systems. Since equipment developers, customers and users have different requirements for the design, installation and operation of air conditioning systems in office buildings, depending on the workload of buildings, location, external conditions, as well as space-planning solutions, air conditioning systems currently come in different types and configurations. Reliable knowledge of classification and the ability to distinguish one system from another is key when choosing the right air conditioning system for the customer. To form a proper understanding of the systems discussed, it is necessary to understand some of the basic terminology and principles of air conditioning systems. These include methods for system design criteria, load calculations (tangible and latent thermal loads, penetration loads, equipment and appliance loads, and air conditioning system requirements).
Improving the wear resistance of cast aluminum alloys by the melt thermal-rate treatment
Authors: Deev V B , Prusov E S , Ri E H , Smetanyuk S V , Feoktistov A V
Published: November 2020

The method of the melt thermal-rate treatment has been successfully tested to increase the macrohardness and abrasive wear resistance of a low-alloy cast aluminum alloy of the Al-Mg-Si system. It was found that an increase in the melt superheating temperature to 900 °C with subsequent isothermal holding and fast cooling to the pouring temperature leads to a decrease in weight loss from 0.359 to 0.324 in comparison with the initial state, which corresponds to an increase in the coefficient of relative wear resistance to 1.11. A good correlation has been found between wear resistance and macrohardness of treated alloys. Application of the proposed approach will increase the service life of aluminum parts exposed to various abrasive effects, however, to further increase the wear resistance, it is recommended to obtain a reinforced composite structure in the Al-Mg-Si system using the melt thermal-rate treatment.
The influence of ovality of the shell-type construction to stress-deformed state
Authors: Kulakov P A , Rubtsov A V , Malyshev V Yu
Published: November 2020

There are many standards that tell us in which ranges the geometry of equipment, piping systems or individual elements of the facility can change. The authors of the article set the task to assess the change in the state of one equipment with possible permissible geometric deviations. As part of the study of the experimental sample, a combination of different variants of ovality was modeled at different pressures up to the yield point. It is shown that there are situations that can reach the yield point at significantly lower loads on the apparatus, as a result of the occurrence of zones of local stress concentrations. Recommendations are given on the real maximum stress-deformed state in the investigated apparatus depending on geometric deviations.
Methods and algorithms for investigating noise and errors in the intelligent measuring channel of control systems
Authors: Jumaev O A , Sayfulin R R , Ismoilov M T , Mahmudov G B
Published: November 2020

The main requirements for an intelligent measuring channel are considered in the article when designing automated control and control systems. The methods for estimating errors are classified and the constituent groups are classified, and some methods for calculating the errors of measuring means and measuring modules of automatic control systems are given.
Combining of orthogonal coding and quadrature amplitude modulation
Authors: Rabin A V
Published: November 2020

Noise immunity is one of the most important characteristics of modern information transmission systems. There is a contradiction between the requirements for the noise immunity of radio engineering systems, due to the capabilities of countermeasures, and the lack of methods for increasing the noise immunity at high spectral efficiency and coding rate. The research of ways to increase noise immunity at a fixed transmission rate through the development of special mathematical methods is an actual task.
Mathematical methods application in the risk assessment technologies implementation at oil and gas facilities
Authors: Filipova N S , Volokhina A T , Glebova E V
Published: November 2020

One of the promising studies in the field of risk analysis technologies is the introduction of mathematical models that make it possible to predict the possible number of industrial accidents victims, depending on the influence of various factors. This article presents the results of data statistical analysis of more than 1270 accidents that occurred at the enterprises of the gas transportation system of the Russian Federation in the period from 2006 to 2018. On the basis of the correlation analysis, the dependence of the influence of such a factor as “type of incident” on the number of victims in accidents was established. With the help of regression analysis and graphical interpretation of the data obtained, it was possible to derive a one-factor mathematical function that reflects the relationship between the total number of victims and the number of victims for a certain factor “type of incident – fall”.
Experimental studies of differences in the distribution parameters of multidimensional spatial-subband object vectors on video images during subband information processing
Authors: Kartsan I N , Zhukov A O , Goloshchapova B A , Zalivin A N , Oleynik I I , Orishchuk S G
Published: November 2020

The variant of representation of various objects on video images in the form of samples of space-subband vectors is resulted. The technique of estimation of differences of parameters of distribution of multidimensional space-subband vectors of objects image is given. As indicators of closeness of two regions of localization of space-subband vectors of different objects, the vector of modules of difference of eigenvalues of corresponding spectral matrices of different objects, received from corresponding subband covariance matrices of objects, is used. Experimental estimations of differences in localization regions of different objects of Copter type using their video images are given. It is shown that when there is an obvious external similarity of objects, the areas of their localization differ significantly in size and orientation. It is shown that the localization region parameters of object vectors are practically invariant to object rotations on the image. The possibility of using spatially sub-band vectors and their estimates to build the decisive rules for the recognition of different objects on video images is shown.
On the issue of reducing the sound level emitted by the intake system of an internal combustion engine
Authors: Deryabin I
Published: November 2020

There is currently a problem of acoustic contamination of environment caused by a large number of vehicles. One of the most intense sources of vehicle noise is its power plant - an internal combustion engine, including the exhaust system and the intake of the fuel-air mixture into the working cylinders. When studying the sound field emitted by the intake system of the engine, two components are distinguished: the gas-dynamic sound arising at the cut of the air intake pipe and the structural (body) sound resulting from sound reradiation by the vibrating walls of the body elements. The study of a technique for improving the acoustic characteristics of the engine intake system by making the sidewalls of the packaged component of the intake system in the form of a three-layer structure (mesh bobbin element - porous sound-absorbing layer - acoustically transparent gastight and watertight film) is examined in the article.
Aerodynamic tests of small sized devices of recycled water-cooling
Authors: Bondar K E , Ivanov S P , Laponov S V , Ibragimov I G
Published: November 2020

There is given a method of aerodynamic resistance coefficient determination of small-sized devices sprinklers of recycled water-cooling (mini cooling towers) in this article. Mini cooling towers are widely used at systems of recycled water supply in enterprises, because it are mobile, services a specific technological units or apparatuses, have a less energy intensity, more effective and safety unlike of oversized. There was compared two types of mini cooling towers in this labor: small-sized cooling tower with twisted air flow and with counter current flow. Also was developed and made the experimental unit for carry out of aerodynamic tests. The experiments on determination of aerodynamic resistance coefficient carried out depending on air flow rate in the interval from 0.5 to 3 m/s and irrigation density from 0 to 12 m3/(m2h). It shown that the sprinkler OB-65 (for mini cooling towers with twisted air flow, with diameter mesh casings 65mm) have more high aerodynamic resistance coefficient than the sprinkler OGGT-65 (for mini cooling towers with counter current flow with diameter mesh casings 65 mm) at the equal parameters of the experiment. Obtained coefficients of aerodynamic resistance of sprinklers in the mini cooling towers with the twisted air flow and with counter current flow approximated by the method of least squares and are presented as linear dependences in logarithmic coordinates of aerodynamic resistance and Reynolds number. It known that the coefficient of aerodynamic resistance is determine by common relation A/ReK.
Design of compact coupler in marine communication systems with uneven power split
Authors: Khiem N K , Hung L Q
Published: November 2020

The work provides for a theoretical study of the coupler in marine communication systems - design and its main characteristics, computer simulation of a compact coupler. The coupler geometry has been redesigned to provide 1 GHz operating frequency and compact size. Artificial transmission lines were installed. Optimization yielded the most similar characteristics of a compact device with the characteristics of a standard device. The area of the device has been reduced by 76.25%.
On the problem of predicting meantime between failures on the basis of data from automated testing of on-board software components
Authors: Kovalev I V , Saramud M V , Losev V V , Testoyedov N A , Karaseva M V
Published: November 2020

The article considers the problem of reducing costs for the development and maintenance of software components. The possibilities of reusing software components and as the result the need for their testing are considered. A method of the repeated testing is proposed. It allows achieving the required level of testability of software components that reduces time costs. This method is a more detailed investigation of the neighborhood of the identified failures and the elimination of already verified areas. The software implementation of the repeated testing method in the framework of the Integrated Development Environment developed by the authors is considered. The presented tool allows designers to automate the re-testing procedure partially. It is possible to predict the time of occurrence of the next error based on the data on the detected errors while testing. It is essentially the time between failures. A de-eutrophication model for predicting the mean time between failures and a software tool that implements the given model are proposed. The results obtained by testing on the known data set are presented. The models and approaches described in the article help to solve the problem that is confirmed by the results obtained using the developed software tools.
A measuring setup with a differential generator photoionization detector for determining biomarkers in exhaled gas
Authors: Ivanova Natalya I , Sidorov Konstantin V
Published: November 2020

The paper presents the results of the development of a differential generator photoionization detector that is capable of determining the concentration of biomarkers in the exhaled gas of a person. There is a description of the differential generator photoionization detector design, its principle of operation. The authors consider the possibility of using a differential generator photoionization detector in a measuring setup designed to determine the concentration of biomarkers during respiration to detect gastrointestinal diseases. The paper presents a setup diagram and describes its operation and elements. The possibility of using the setup for determining the ammonia concentration in the range of 10–200 ppm and measuring the hexane concentration in the range of 0.5–1 ppb to a precision of ±10% has been experimentally confirmed.
Three-dimensional thermal calculation of the radiant chamber of a box-type tubular oven
Authors: Sadykov A V
Published: November 2020

The paper discusses three-dimensional stationary task of radiation-convective heat exchange under conditions of combustion of gaseous fuel. To solve the problem, a differential method is used. A set of programs implementing a differential method is used for numerical studies of the spatial distribution of temperature, averaged values of the turbulent flow rates of flue gases in the radiant chamber of a tubular furnace of the box type. The diagram of the furnace with injection burners located on the roof of the radiation chamber, differential equations describing the physical processes in the furnace are given. Discrete analogues of storage equations are obtained by the control volume method. Difference grid of “chess” type is used. To solve the radiation transfer equation, the discrete ordinate method is used. The obtained distributions of surface densities of heat flows to the heating surface are shown. The average velocity of combustion products is plotted.
The calculation of the wavelengths of natural electromagnetic oscillations of a cell
Authors: Kharlanov Aleksandr V
Published: November 2020

The equations for calculations of wavelengths of natural electromagnetic oscillations of a spherical cell were obtained. The cell is considered as a spherical resonator filled with an isotropic dielectric. New way to solve Helmholtz equation was obtained. The results of calculations of resonant wavelengths of a cell depending on their size and dielectric permittivity are presented. The calculation shows that the value of the maximum critical wavelengths lie within the submillimeter range.
Methods of comparative analysis
Authors: Bolbakov R G , Sinitsyn A V , Tsvetkov V Ya
Published: November 2020

The article researches methods of comparison: object comparison and property comparison. It reveals the content of qualitative and quantitative comparison methods; shows the difference between the qualitative and quantitative comparison estimate; introduces analytical concept of “comparison operator” (the example of a comparison operator shows the Trinitarian essence of comparative operations); shows that comparison is carried out in all four measurement scales; reveals the content and features of one-parameter and multi-parameter comparison methods. The one-parameter comparison allows for obtaining stable general qualitative and quantitative comparison estimates. The multi-parameter comparison allows for obtaining general qualitative estimates and partial quantitative comparison estimates. Both comparison methods are based on the Trinitarian model. This article describes the application of nomothetic and ideographic approaches for multi-parameter comparison, and explains that the nomothetic and ideographic methods of cognition complement each other. The article proves the necessity of using Trinitarian models as a basis for comparison to replace dyadic models.
The influence of aggressive environmental factors on the corrosion-mechanical wear and the risk of depressurization of oil field pipelines
Authors: Elagina O Yu , Nakonechaya K V , Prygaev A K
Published: November 2020

The work is devoted to assessing the risk of depressurization of field pipelines operating under the conditions of the combined action of a corrosive environment and mechanical impurities. For a comparative assessment of the contribution of the corrosion factor to the fracture process, studies have been carried out on the development of corrosion processes on 20A and 09G2S steels in field media of different aggressiveness. The rate of destruction of the pipe metal under the influence of mechanical impurities was studied using the adapted ASTM G65 methodology, which makes it possible to evaluate the complex effect of corrosion and mechanical factors. Based on the data obtained during the study, equations were derived that characterize changes in the corrosion rate depending on the value of the hydrogen index (pH), degree of mineralization, CO2 content and temperature of the production medium and the content of solids. Using the obtained dependences, a methodology was developed for predicting the risk of depressurization of field pipelines depending on the composition of the transported medium and the dynamics of its change during field development. Application of the developed methodology will allow assessing the risks of depressurization under the influence of corrosion-mechanical factors in the design of oil field pipelines.
Snowbreak fence modelling
Authors: Tsvetkov V Ya , Kudzh S A
Published: November 2020

The purpose of this work is to study a snowbreak fence model based on standing wave effects. The article offers a new snow protection model based on aerodynamic effects, using the principle of a standing air wave. According to the laws of physics, a standing wave can occur either at the end of a closed pipe or at the end of an open pipe. The standing wave in an open pipe can be calculated by gas dynamics formulae. A similar effect occurs in arranging the snow protection with apertured shields. The results of a model experiment are presented to justify the retention of snow masses before the apertured shield. Two options of shields were considered, namely, standard and modified. The modified option was found more effective.
Methodology for assessing external losses of repair enterprises of the agro-industrial complex when implementing a quality management system
Authors: Leonov O A , Temasova G N , Malykha E F
Published: November 2020

The problem of assessing the cost of quality when creating a quality management system at technical service enterprises in the agro-industrial complex is very relevant. To date, there is no generally accepted methodology for assessing these costs. The problem of assessing external losses is especially relevant, since external losses are associated with inconsistencies discovered by the consumer, and the consequence of this will be economic losses and a decrease in demand due to the poor quality of a product or service. We have developed a methodology for assessing external losses for repair enterprises of the agro-industrial complex. The method for assessing external losses is based on a process approach, that is, losses are estimated separately for each process. This allows you to identify process inconsistencies and take action to reduce the risk of their occurrence in the future. We also tested the methodology and estimated external losses during the repair of YaMZ engines.
Measurement risk management method at machine-building enterprises
Authors: Leonov O A , Shkaruba N Zh , Kataev Yu V
Published: November 2020

Issues related to ensuring the quality of measurements in mechanical engineering has been discussed. The purpose of work on metrological support of measurements at machine-building enterprises have been defined. As an effective tool for improving the quality and effectiveness of measurement processes within the metrological support system, it has been proposed to develop and implement a risk management process. The theoretical foundations of the risk management process have been analyzed and the five main stages of this process. The risks of the system of metrological support of measurements has been formulated and possible consequences of risks have been determined. Taking into account the peculiarities of measurement processes, a special method for managing measurement risks has been developed. The methodology includes: selecting an object for risk management of measurement processes, calculating economic losses from errors caused by the influence of measurement errors (errors of the 1st and 2nd kind), ranking measurement processes depending on the magnitude of possible economic losses and the probability of their occurrence, and developing measures to reduce risk.
Environmental safety of livestock facilities
Authors: Simbirskikh E S
Published: November 2020

The relevance of the problem of environmental protection in agriculture is increasing in modern conditions due to the processes of pollution of natural resources used in agricultural production, industrial, construction and other non-agricultural enterprises. These pollutants lead to a decrease in soil fertility and productivity, deterioration of the quality of water and the atmosphere, and damage crop and livestock production, which leads to a loss of agricultural products and deterioration of their quality. And the very activity of livestock facilities is accompanied by the release of various pollutants (including greenhouse gases) into the air, the consumption of large volumes of drinking water and the discharge of pollutants into water bodies as part of wastewater, the formation and placement of a large amount of organic waste. The article offers a list of measures to reduce the polluting influence of livestock complexes on the surrounding area.
Impact of compression shock loads on buried pipelines
Authors: Egorov Anton V
Published: November 2020

Topical issues of interaction of metal pipes with subsoil in the structures of hidden (underground) main pipelines serving for transporting oil or gas are considered. The shock loading of pipes from the subsoil side, caused by seismic earth movements, was investigated. The loading consists of the total compacting pressure and the force local pressure. The calculations were carried out in order to establish a possibility of local buckling of the pipe (pipe wall buckling). The problem was solved in real time, taking into account the bulk of the pipe– subsoil structure and technological deviations. A 3D finite element model of the structure with unilateral constraint along the surface of the pipe-and-subsoil contact has been developed, which is presented in the form of a thick-walled cylinder. The pipe is considered as an elastoplastic body; the subsoil is considered as linearly elastic. The calculations were performed using the LS-DYNA software package in a nonlinear dynamic formulation. Numerical analysis of the stress-strain state of the steel pipe – subsoil structure showed that there were critical loads at which the pipe wall buckles. It is concluded that it is necessary to carry out dynamic calculations of buried pipelines located in seismically active regions.