bluuebunny/crossref_metadata_2025_split huggingface dataset:
Numerical Investigation of Centrifugal Compressor Radial Inlet
Authors: Gileva L , Kozhukhov Y , Gilev K , Fateeva E , Nhan N H 
Published: December 2020

Abstract
Efficient compressors designs reduce the overall energy consumption of industrial buildings. The inlet chambers for turbocompressors have a significant influence on the whole stage operation. An uneven flow in the inlet of an impeller can turn up to be the cause of stage efficiency drop, and also it is able to narrow down the range of its operational stability which in turn is an essential negative factor. Currently, there is no clear methodology of the design of the inlet radial chambers which makes it difficult to design the compressor. The purpose of this work is to develop recommendations for the designing problem formulation of the centrifugal compressor radial inlet chamber and also modify the existing design method for inlet chambers. During the previous research, the most acceptable model of the inlet chamber was obtained with the help of real and numerical experiment. In this paper, different geometric parameters of the inlet chamber are changed and then calculated by means of numerical experiment. Their influence on the inlet chamber loss coefficient, relative velocity distribution and static pressure coefficient is investigated.
Numerical study of the equivalent roughness effect on the low-flow centrifugal compressor impeller characteristics
Authors: Yablokov A , Kozhukhov Y , Sadovskiy N , Danilishin A , Nguyen M H 
Published: December 2020

Abstract
The article presents the results of a numerical study of the effect of equivalent sandgrain roughness on the characteristics of a low-flow centrifugal compressor stage. Low-flow stages are widely used in high-pressure compressors as the last stages. These compressors are used for natural gas booster compressor stations, as well as in technological processes for the production of methanol, ammonia, high - pressure polyethylene, etc. The efficiency of the low-flow stages is lower than that of medium-and high-flow centrifugal compressors stages. Stages operate at high pressure and have low gas volume flow rates. For this reason they have narrow channels of the flow part, significant friction and leakage losses. The study was conducted in the Ansys CFX 19.2 software package. In the first part of the study, the low-flow stage numerical model is validated with the test results. Full-scale tests of the stage were carried out at the LPI-SPbPU earlie. In the second part of the study, impeller equivalent sand-grain roughness numerical study carried out. As a result, the characteristics of the stage were obtained at four different values of equivalent sand-grain roughness ks. The impeller losses were estimated. It is established that when the ks values increase, the polytropic head and efficiency values do not decrease equally over the entire characteristic. Characteristics are significantly reduced in areas of high expenditure and change slightly with minimal expenditure. The internal head coefficient varies slightly depending on ks.
To the problem of efficiency of reliability assessment of agricultural units
Authors: Klimenko N P , Ustinova N P 
Published: December 2020

Abstract
The theoretical analysis of the processes occurring in operation, which determine the reliability of the elements of agricultural units and machines, made it possible to develop a universal approach to the construction of mathematical models of reliability. Practical use of the proposed reliability models is advisable both for accelerated assessment and for predicting reliability at the resource design stage. This article proposes a method for assessing and predicting the reliability of a complex system, if there is information about the reliability level of a sample of its elements.
The concept of hacking growth and technological breakthrough of Russian agricultural machinery industry with the use of engineering marketing approach
Authors: Lyubanova T , Lisitsin V , Oleynikova Y , Shcherba L 
Published: December 2020

Abstract
The article is dedicated to the consideration of hacking growth theory in the context of technological breakthrough of Russian agricultural machinery industry with the use of engineering marketing approach. Taking into account the results of analysis of Russian agricultural machinery dynamics in recent years, the prospects and opportunities for overcoming current problems (in particular, insufficient competitiveness and technological gap) are discussed on the basis of investigation of existing approaches to technology business development. The solution is suggested which consists in creating interdisciplinary growth teams capable of developing and implementing relevant innovative solutions, as well as providing rapid spread of changes. The issues of internal transformation necessary for the adjustment of Russian enterprises to the changing external environment in the context of knowledge-based economy development are considered in the paper.
Improvement of the methodology for the design of technological transport of timber industry enterprises
Authors: Ivannikov V A , Bukhtoyarov V N , Kvitko K S , Shvyrev A N 
Published: December 2020

Abstract
The article deals with the formation and optimization of the technological transport system of a timber enterprise. Problems were identified in the formation of cargo flows of forest material. These include poor development of methods for designing transport systems in the timber industry and disunited transport links in the operation of the enterprise. Computer simulation allows the operator to change the parameters of the designed system to optimize it. A multi-level algorithm for designing the transport system of the LPC is also proposed, including: determining the initial parameters for the design; calculating the number of vehicles; developing a simulation model of the production process in the LPC; calculating the technical characteristics of the transport system; developing an algorithm for managing the transport system; selection of the transport system option. An analytical calculation of the use of different quantities of trucks when loading vehicles is made in order to find an economically profitable number of them. As a result, calculations were made to compare the performance of the transport system with different quantities of loading equipment. When we received them, we saw that changing the number of loaders affects the capacity of the entire transport system.
Wind power plants functioning model in the power supply system
Authors: Kapov S , Alekseenko V , Sidelnikov D , Orlyanskaya I , Likhanos V 
Published: December 2020

Abstract
The system of complex energy supply of various objects is considered, existing problems in the field of wind power engineering are identified, those that leave complex energy supply using renewable energy sources are analyzed, and the quality of supplied energy is assessed by the efficiency factor. The structural model of wind power plant (HPU) functioning as a subsystem in the autonomous power supply system was considered separately. Methodological bases of designing in the form of structural scheme of methodology of development and creation of rotor HPU have been developed. All stages of designing and development of a wind power plant are analyzed.
Computer-digital technique for evaluating the geometry of the interface of the weld with the base metal
Authors: Assaulenko S S , Lyudmirsky Y G , Kharchenko V Y , Chernogorov A L 
Published: December 2020

Abstract
On the basis of the coordinate measuring machine CMM, there is a computer-digital technique for measuring the transition radius and the angle of conjugation of the metal with the base metal φ. It allows in automatic mode, with high accuracy and reliability, to determine the above parameters of welds, which are used in calculating stress factors and in assessing the fatigue strength of welded structures.
Controlling 3-d model of two exoskeleton links with variable length
Authors: Borisov A , Borisova V , Konchina L , Maslova K 
Published: December 2020

Abstract
3-D models of one-link and two-link exoskeletons with variable-length links are considered. The construction of a multi-link model is done from a simple one to a complex one. The 3-D analysis of the one-link model with one fixed point is done at first. After that, the two-link model with variable-length links is considered. It has been found that increasing the number of links leads to difficulties in composing the system of differential equations of motion relating to a longer time required for building it, even if the modern systems of computer mathematics are used. The proposed link model can be used for designing the working exoskeleton or anthropomorphic robot. The exoskeleton link consists of two absolutely rigid weighty sections at the link ends and of a weightless section between them. The analytically synthesised trajectories of the exoskeleton motion are given. The problem of finding controlling torques and forces is solved numerically and the solution results are presented graphically. The application of the proposed variable-length link model to an exoskeleton will reduce the load on the User’s joints, increase the User’s comfort and the force applied by the exoskeleton operator, as well as the period of its uninterrupted operation.
Algorithms Of Using Statistical Methods in The New Software Module
Authors: Golubeva O , Mirnyy V , Pogorelova A 
Published: December 2020

Abstract
The article is devoted to the developed software module for statistical control of production quality allowing to use the following quality tools: Pareto chart, Shewhart control charts (map of mean values and range chart), scatter chart, control charts of the proportions P and the number of nonconforming units nP, control charts of the number of nonconformities C and the number of discrepancies per unit U, Ishikawa diagram. The article can be useful for specialists involved in statistical quality control and looking for an alternative to other software that can be introduced into the production process.
Simulation of the hydraulic system of a device with self-adaptation by power and kinematic parameters on the working body
Authors: Khinikadze T , Pershin V , Karagodskaya Y 
Published: December 2020

Abstract
At present, Russia has adopted a course towards the creation of intelligent machines and equipment. This also applies to mobile technological machines for road construction and municipal purposes, the difficult operating conditions of which and the complexity of the proposed technical solutions hinder the implementation of this project in practice. Therefore, the design and creation of executive devices with a self-adaptation function for this class of technology is an urgent task. Materials and methods. A device with a hydraulic drive function with self-adaptation to load and coordination of kinematic and power parameters of the main movement and feed movement of the working body of a rock drilling rig is presented. For research and design of the device based on the methods of mathematical modeling of the hydraulic drive and adaptive systems, its mathematical model is proposed. Discussion and conclusion. The mathematical model presented in the article shows the fundamental possibility of the proposed device for implementing the principle of self-adaptation in terms of load under external and internal disturbing influences during its operation.
Modification and optimization of miller – rabin simplicity test algorithm implemented by parallel computation
Authors: Cherckesova L , Safaryan O , Trubchik I , Chumakov V , Yukhnov V , Yengibaryan I 
Published: December 2020

Abstract
The project of modification and optimization Miller–Rabin’s simplicity test algorithm implemented by parallel computation in the programming language C# is presented, which works faster on comparison with standard iterative algorithm by 50%, which makes it easier to create the keys for such well–known encryption algorithms as RSA, DSA, etc. These methods are similar on their functionality, but have a different estimation of structural complexity that has been shown various tests. Proceeding from it, modified by authors Miller–Rabin’s algorithm realized through parallel calculations is more reliably and faster, than the standard algorithm, that is experimentally confirmed in practice.
Simulation of bending and torsion tests of non-welded and welded direct-formed rectangular hollow sections
Authors: Kukhar V , Sahirov Y , Hornostai V , Markov O , Nahnibeda M 
Published: December 2020

Abstract
The paper implements a method for analyzing the stress-strain state of rectangular hollow sections (RHS) by finite-element modeling (FEM) of tests for three-point bending and torsion. Design schemes, 3-D solid-state and deformable models have been developed using the automated analysis and CAD/CAE system software, made it possible to obtain equivalent stress distributions and displacements in models. A simulation of tests for RHS with a cross section of 40 mm × 50 mm, manufactured in two ways, was carried out: (a) by direct-forming of galvanized steel strips on roll-forming mill in a semi-closed section with a longitudinal gap of 0.5 mm between the edges formed on a 40 mm web (DF-RHS); (b) similar direct-forming to the closed section and next welding the edges to a longitudinal weld along the web middle of 50 mm (DFW-RHS). RHS with various wall thicknesses (t = 1.93 mm, 1.84 mm and 0.7 mm) was investigated, given the design features that depend on the manufacturing processes of structural sections. It was found DFW-RHS is stiffer by at least 50% compared to DF-RHS, which allows to savings the metal by reducing the RHS wall thickness by 62% while maintaining the same stiffness and ensuring high strength of structural section.
Stress modelling in natural foundation
Authors: Agakhanov E K , Agakhanov M K , Agakhanova R E 
Published: December 2020

Abstract
Modeling methods are widely used in solving problems of deformable solid mechanics. Modeling of problems in the mechanics of a deformable solid is carried out using similarity criteria. Based on the similarity criteria, the model is made, the loading conditions are determined, and the transition from the values on the model to the values of the full-scale design is performed. The similarity criteria may be obtained either from the similarity theory or with the use of the dimensional analysis. The authors use the system of equations for a mixed problem in the elasticity and plasticity theory as well as the scale method and determine the similarity criteria for modelling the stresses in the foundations of structures. They note the restrictions on the choice of similarity factors for loose soils and the possibilities of the use of centrifugal modelling for the aforesaid scale method. They also note the special features of modelling the coherent soils.
Justification and development of an adaptive algorithm for stochastic optimization of a multi-criteria process
Authors: Kulikov Vladimir 
Published: December 2020

Abstract
The paper considers aspects of the development of algorithms for optimizing complex systems, and also develops an algorithm for solving problems of convex stochastic programming with a non-smooth goal function. The principles of constructing adaptive procedures for adjusting the parameters of variable gradient optimization algorithms are proposed. Note that in almost any iterative algorithm, as a rule, there are parameters that require their adjustment. To control and adjust parameters, - criteria are formed that determine the quality of adjustments. At the same time, the problem of determining the best value of the adjustment parameters belongs to the same class as the original optimization problem. Usually, iterative algorithms that work in the same class of optimization problems are used to adjust the available parameters. Thus, it turns out that two algorithms work simultaneously, in the source space and in the parameter space. Since algorithms are adapted by parameters during operation, this type of algorithm is called adaptive. The current stage of development of computer technology and mathematical support requires the development of algorithms that must function successfully without the User’s participation, both in the process of solving the problem and in the process of finding a solution to the problem. The paper provides recommendations for software implementation of adaptive stochastic algorithms and construction of computational procedures for stochastic computational experiments based on them.
Estimation of the losses coefficient of the vibrational energy of the woodworking technological system
Authors: Chukarina N , Meskhi B , Beskopylny A 
Published: December 2020

Abstract
Domestic machine tool equipment is not worse than foreign analogues in terms of product processing accuracy, productivity and reliability. However, almost all machines (including woodworking ones) create sound pressure levels at the operator’s workplaces that significantly exceed the maximum permissible values. Compliance of vibroacoustic characteristics of technological equipment with sanitary standards is not only one of the most important ergonomic criteria, but also largely determines the competitiveness of domestic equipment. The article developed methods of acoustic calculation of metal-cutting equipment, which take into account the coefficient of losses of the vibrational energy of the source, which is a frequency-dependent parameter. Experimental results and regression relationships were obtained for steel plates of various thicknesses, rolled products of multiple configurations, for transport machines and for glazing elements. For woodworking equipment, this data is obtained only for multilayer materials. For various types of wood, at present, such studies have not been carried out, which in fact determines the relevance of the materials in this article.
Determination of the density of concrete by ultrasonic velocity
Authors: Korolkov D , Mordvinov A , Trebukhin A 
Published: December 2020

Abstract
This article discusses the issue of determining the density of concrete using the ultrasonic method of testing concrete structures. The article discusses traditional methods for determining the density of concrete from selected samples and using radioisotopes. The advantages and disadvantages of these methods are highlighted. The authors proposed the use of an ultrasonic method for determining the density of concrete. From the equations of the propagation velocity of ultrasonic waves in solid media, the density of the material is expressed for the case of transverse and longitudinal waves. The authors proposed to use the derived equations to determine the density of concrete during ultrasonic testing of concrete and reinforced concrete structures. The authors provide explanations for determining the parameters of concrete included in the equations. The factors that influence the determination of the ultrasound velocity are given. Using the proposed formulas, you can calculate the density of concrete structures.
Atmospheric air pollution monitoring using flying robotics
Authors: Polyakov R , Fedyanin V 
Published: December 2020

Abstract
This article discusses a method for detecting a source of atmospheric air pollution (for example, carbon monoxide) using flying robotic equipment. The relevance of this study is the autonomy of methods for detecting a source of pollution with a given accuracy. To achieve this goal, the scheme of a mobile instrument platform in the form of an electromechanical system and the problem of finding a source of pollution were considered. By calculation and experiment, the radius of the circle and the speed at which the maximum and minimum CO concentration will be measured were obtained, an algorithm for the method for determining the coordinates of the CO concentration source based on a mobile instrument platform was proposed.
Specific environmental risks of the Lena-Tunguska oil and gas province
Authors: Gorlenko N V , Murzin M A 
Published: December 2020

Abstract
Oil and natural gas make up a significant part of the global economy, and the extraction of these natural resources is an essential industry. Recently, the rate of extraction of natural resources has increased significantly, the accumulated growth in exploration and discoveries of new and previously mothballed deposits, of course, entail the huge costs for restoring the natural environment. Currently, most of the deposits are located in the northern territories, where there are additional risks to the natural environment. In addition to unfavorable climatic factors that complicate the process of extraction and restoration of land, soils of natural areas are also represented by permafrost, which complicates both the extraction process itself and the process of subsequent land restoration. The impact on the atmospheric air has its negative consequences, at present most of the negative emissions and flaring have been significantly reduced. Nevertheless, there are undoubtedly risks for workers and the living environment in mining areas. In this article, we have tried to present and calculate the environmental risks for the deposits of the Leno-Tunguska oil and gas province. The paper presents the main indicators of the impact on the environment: atmospheric air, soil (waste drilling mud and industrial waste), and the impact of harmful factors on the health of workers. Currently, this impact makes the main negative contribution. The damage is given in a specific equivalent, which gives us an equivalent impact, due to the fact that the total cost of the negative impact is divided by the volume of extracted raw materials.
Hydrotechnical structures
Authors: Abdrazakov F , Pankova T , Orlova S , Mikheeva O , Mirkina E , Mizyurova E 
Published: December 2020

Abstract
When using modern methods of analyzing information about accidents at hydrotechnical structures, one can make forecasts of the probability accidents and calculate the possible consequences. Estimation of qualitative and quantitative characteristics of the accident at HTS barrage regulatory structure on the river Bolshoy Uzen near the village Alexandrov Gai of Alexandrov-Gai district Saratov region, the emergency situations and their consequences was carried out in accordance with the decree of the Government of the Russian Federation dated 21.05.07 N° 304 “On the classification of emergency situations of natural and technogenic character” (with amendments and additions of May 17, 2011). According to the decree of the Government dated 21.05.07 N° 304 “On the classification of emergency situations of natural and technogenic character” the accident at HTS barrage regulatory structure of Alexandrov-Gai district refers to the emergency situation of municipal character, as in the breakout barrage regulatory structure the emergency zone does not extend beyond the territory of the municipality; in the case of hydrodynamic accident the life of people, property of individuals and legal persons, the environment will not damage, and the total amount of detriment caused by damage to the health of 1 person and water supply disruption (the most difficult situation), will not exceed 5 million rubles. The object is not potentially dangerous.