bluuebunny/crossref_metadata_2025_split huggingface dataset:
Calculation of profiled flooring using the mid-surface equation of the orthotropic plate
Authors: Makeev S A , Komlev A A , Makarov S E , Makarova I D 
Published: May 2021

Abstract
Steel profiled flooring is a structurally orthotropic material, since its orthotropy is not due to the material properties, but to the cross-sectional shape obtained at the production stage. Taking into account the orthotropic properties of the profiled flooring during the calculation is extremely rare, since it is a laborious process. A method is proposed for calculating profiled flooring taking into account its orthotropic properties, which is implemented in various computational software systems. The results of calculations in the Matlab package and the PC Lira-CAD are presented.
Imitation modeling of passenger traffic delivery activities
Authors: Muhamediyeva D K , Mirzaraxmedov S Sh 
Published: May 2021

Abstract
In this paper, the concept of building a new route network is investigated. The guiding idea of the concept is the functioning of transport as a coherent system. Under the given conditions, it is impossible to organize the stable operation of the passenger transport complex without eliminating the existing contradictions. In order to establish a balance of interests of all cooperating parties, a mechanism for regulating the route network is proposed in the work, the calculation of which makes it possible to select the type of vehicle on the route, as well as calculate the number of flights, based on the condition of achieving a break-even transport process for carriers of various forms of ownership.
Generic complexity of solving of equations in finite groups, semigroups and fields
Authors: Rybalov Alexander , Shevlyakov Artem 
Published: May 2021

Abstract
The paper is devoted by investigation of generic complexity of the algorithmic problem of solving of systems of equations in finite groups, finite semigroups and finite fields. We show that if this problem is intractable in the worst case and P = BPP, then there is no polynomial strongly generic algorithm, which solves it. The first author is supported by Russian Science Foundation, grant 19-11-00209. The second author is supported by Russian Science Foundation, grant 18-71-10028.
Domains identification by the parameter values in multidimensional space
Authors: Zykin S V , Zykin V S 
Published: May 2021

Abstract
As a result of cluster and discriminant data analysis, the objects are distributed among different classes represented in the multidimensional space of parameter values. At the next stage, it is relevant to use the results obtained in various applications. The most frequently solved task is the diagnostics of a newly received object when the class of the object is determined through parameter values. In terms of a data view model, the problem can be reduced to determining a domain in parameter space, the new object belonging to this domain. The solution to this problem depends on the way the data analysis results are described and presented. Previously the graphic data model was considered to describe the domains separated by surfaces in the multidimensional space. Moreover, a constructive approach was proposed to describe an error in the representation of the boundaries, making it possible to take into account the experimental data errors. The mathematical model proposed in the given article is used to develop a domain identification algorithm by the parameter values in the multidimensional space. The proof of correctness and the estimation of computational complexity are provided for the algorithm. The results obtained make it possible to use the algorithm to calculate various characteristics of objects: state, intervals of existence, etc.
Features of practical application of electric power system’s stability estimation methods
Authors: Bubnov A V , Barskov V V , Kirichenko A N , Schekochikhin A V , Malgin G V 
Published: May 2021

Abstract
Timeliness of the topic is conditioned by the need to keep up ample of static and transient stability margins in modern electrical power systems. Object of an article is to give a determination of present methods of evaluating damping of systems with synchronous machines, in the context of their effectiveness. And also to estimate the effectiveness of these methods in the performance of the task concerned with selecting of best settings of automatic excitation regulators of synchronous generators. This analysis led us to the conclusions, in particular, about possibility to apply the root locus methods in estimating stability of electrical power systems, and also about genericity of the matrix method with the use of QR-algorithm, which is widely used in practice of calculating stability.
Forecasting electric power consumption of technocenosis objects on the basis of values from transformed vector rank distribution
Authors: Kivchun O R 
Published: May 2021

Abstract
The article examines a technique for predicting the electric power consumption of technocenosis objects on the basis of the values of the transformed vector rank distribution. This technique includes the following stages: preparing data on electric power consumption, calculating an additional resource for technocenosis objects, forming transformed rank distribution and forecasting its values. The theoretical basis of the methodology was formed by the tenets of the theory of vector rank analysis, the methodology of functional rank analysis and the theory of mathematical statistics, as well as the concepts “technocenosis”, “MS-cenosis” and “bifurcation”. Its distinctive feature is the possibility to take into account the external control effect of a higher power system-MC-cenosis by adding or deducting an additional resource calculated using the system of transformed vector rank distributions. The additional resource is the difference between the values of the technocenosis located on the vector rank distribution of the higher MC-cenosis and the lower permissible value of the lower boundary of permissible values. The presented technique can be implemented in software and hardware complexes and situational centers for electric power consumption control in the area, energy system, transport network complex, large infrastructures and enterprises. The results will significantly supplement the methods of resource management for large infrastructure and energy facilities and form a resource consumption plan individually for each object.
Investigation of transients in a submersible electric motor with a downhole compensator
Authors: Markova A A , Kopyrin V A , Deneko M V , Khamitov R N , Logunov A V 
Published: May 2021

Abstract
Currently, the energy efficiency improving into the oil production is an important task. The main electricity consumer in the electrical complex structure of the electric centrifugal pumps’ installation is a submersible asynchronous electric motor. The power factor of these electric motors varies from 0.75 to 0.85. It leads to the losses’ increasing in the conductive elements of the complex. The use of downhole reactive power compensators is the most potential way to increase the power factor into the submersible asynchronous electric motors. In the course of pilot tests there are some cases of the protection devices for downhole compensators’ false triggering. It is recorded when the control station is switched off. It leads to the energy efficiency decreasing into the oil production. The purpose of this study is to research the transients in a submerged asynchronous electric motor equipped by the downhole compensator when the power supply is switched off. The task of the study is to determine the transient process’ parameters, in order to prevent false triggering of the downhole compensator protection devices. Simulation modeling of a submerged electric motor with a downhole compensator is performed in the Matlab Simulink. A simulation model of a submerged electric motor with a downhole compensator is developed to study transients when the power supply is switched off. The characteristics for the transient process of the voltage and current into the downhole compensator are obtained during the simulation modeling. The current surge for the capacitors’ discharge of the downhole compensator is 260.7% relative to the rated current at the time of the power supply disconnection. Prevention measures off false triggering for automatic shutdown devices of the downhole compensator are proposed.
Improvement of the methodology for assessing the quality of the traction motor collector repair
Authors: Shkodun P K 
Published: May 2021

Abstract
The data of the traction motors collector profiles were obtained experimentally. A traction motors profile control device was used to measure the traction motors profile. The spatial spectra of the collector profile harmonics are calculated. The spatial spectrum of the traction motors profile is divided into three ranges: the first range characterizes the macroroughness of the collector, the second range determines the roughness of the traction motors profile of average values, the third range characterizes the microroughness of the traction motors profile. The amplitude of the harmonics of the first and second frequency ranges significantly decreases after the repair of the traction motor collector. Linear correlations have been established between the range of the reconstructed profile with a limited number of harmonics and the root mean square value. It is proposed to use the values of the amplitude of the reconstructed signal of the collector profile with a limited number of harmonics (three ranges). The proposed diagnostic parameters of the recovered signal swing for three ranges make it possible to assess the quality of the repair performed. The parameters allow to refine the methodology for diagnosing the technical condition of the traction motors profile using objective monitoring tools.
Development of mathematical models for the short-term forecasting of daily consumption schedules of active power by Moscow
Authors: Vyalkova S A , Kornykova O , Nadtoka I 
Published: May 2021

Abstract
The present article presents the results of research into solving the problem of increasing the accuracy of forecasting power consumption. The purpose of these studies is to develop mathematical models for short-term forecasting of daily schedules of active power consumption in Moscow, taking into account meteorological factors. Research has been carried out on four predictive models based on singular spectral analysis (SSA), least-squares method, trigonometric interpolation, neural and neural fuzzy networks (NFN). It is shown that the NFN and hybrid model based on MSSA and NFN has the smallest error.
The basics of choosing the composition of complex modifiers
Authors: Eremin E N 
Published: May 2021

Abstract
Based on the analysis of the thermodynamic conditions of stability of the process of heterogeneous nucleation of phases in the melt, it is shown that the growth of the solid phase on the substrate is determined by the properties of the transition layer, which should provide the maximum increment in the chemical potential that changes the dielectric constant and density of the component.
On the basis of the analysis, the criteria for the selection of complex modifiers, consisting of exogenous refractory particles-inoculators and activating additives – inoculators and activating additives-protectors. To intensify heterogeneous nucleation in the melt, inoculators should be selected based on the conditions of resistance to dissolution and the highest electrical conductivity, while catalytic activating additives – from the condition of their affinity for particles of inoculators, contributing to the completion of their crystal lattices and the ability to ensure the formation of a transition layer of a stable hardly soluble or weakly dissociating chemical compound having a density close to that of the melt, which reduces the density differences between the particle and the melt at their interface.
The effect of barium titanate on the dielectric constant of a composite based on an epoxy press material
Authors: Eremin E N , Kukushina K G 
Published: May 2021

Abstract
The paper considers the effect of the introduction of barium titanate (BaTiO3) on the dielectric properties of a composite material based on an epoxy press material. The technology for preparing a composite material with a high dielectric constant is presented. The physicomechanical and dielectric properties of the composite are presented. The possibility of increasing the dielectric constant of the material is shown, as well as the technology of manufacturing the housing elements of spiral antennas. It was found that filling with 30 % of the BaTiO3 mass increases the dielectric constant by 1.5 times.
X-ray spectral analysis of surface structures formed on copper alloys during film fasting
Authors: Kubich V I , Cherneta O G , Yurov V M , Oleshko V S 
Published: May 2021

Abstract
The paper establishes the nature of the redistribution of chemical elements and their concentration in secondary surface structures for the material systems “steel 45XN2MFA-grease-BrOTsS4-4-2.5”, “steel 45XN2MFA-grease-BrOTsS4-4-4”, “steel 45XN2MFA-grease-L-63 ”, tested under the conditions of simulating film starvation when lubricated with 15W40 Lukoil-Super SAE SG/CD engine oil. Since the formula obtained by us includes the Gibbs energy, the self-organization of the structure under consideration naturally also enters. General laws of self-organization are observed when a number of conditions are met: irreversibility, openness (nonequilibrium), nonlinearity, instability (coherence), dissipativity. All these elements were observed and described by us in this work. It is due to self-organization that the distribution of chemical elements carbon and oxygen occurred on the surfaces L63 and BrOF4-4-4. To this effect must be added a decrease in the surface tension of the lubricant.
Analysis of the stress state of cylindrical workpieces during pipe end crimping with wall thinning
Authors: Larin S N , Larina M V , Nuzhdin G A 
Published: May 2021

Abstract
Workpices with different cross sections in the orthogonal direction along the height can be produced by crimping of hollow cylindrical blanks. This operation is highly productive and makes it possible to obtain various types of connectors. This article discusses simultaneous crimping and thinning of the workpiece wall at the exit from the deformation zone. During crimping, the thickness of the workpiece grows in the deformable part. In view of this, significant stresses may arise in the deformation zone. Therefore, selection of process parameters that provide the best stress state of the products is relevant. This article presents a study of the stress state in the combined process of crimping with wall thinning.
A study of dynamics of the operational performance of a single-bucket excavator, taking into account the operating time during construction of transport infrastructure of oil and gas facilities
Authors: Salikhov R F , Permyakov V B , Filippov Yu O , Grusnev M G 
Published: May 2021

Abstract
The paper presents the results of studies of the impact of operating time of single-bucket excavators on their operational performance. The results of production experiments made it possible to establish the dependence of the pressure change in the hydraulic system of the excavator during the process of cutting soil on the operating time. This parameter characterizes the variation value of the cutting resistance of soil at the cutting edge of a bucket, the duration of operation cycle and its operational productive capacity. Based on the results of the study, a technique has been developed that permits to determine economically feasible periods of effective operation of excavators, as well as to establish the optimal technological parameters for cutting soil: the thickness of the soil shavings and speed of its cutting by an excavator.
Angular displacement sensor based on oscillistor effect
Authors: Cheredov A I , Shchelkanov A V 
Published: May 2021

Abstract
The development of angular displacement sensors with a frequency output signal based on the oscillistor effect in electronic germanium is considered. The experimental results of the dependence the oscillistor oscillation frequency on angular displacement are described in the paper. Angular displacement sensors sensitivity is 1.0 kHz/deg at temperature of 295 K. With decreasing temperature the sensitivity increases and reaches 40 kHz/deg at 77 K. The design of the oscillistor-based sensor is presented.
Variable formation plasticity matrices of a three-dimensional body when implementing a step loading procedure
Authors: Klochkov Yu V , Nikolaev A P , Vakhnina O V , Sobolevskaya T A , Klochkov M Yu 
Published: May 2021

Abstract
Nowadays, the task of creating and improving computational algorithms for determining the stress-strain state (SSS) of technosphere objects and systems, taking into account the physically non-linear stage of operation of the material of structures and their elements, is quite relevant. A variational approach to the formation of a plasticity matrix at the loading step for a three-dimensional body is presented on the deformation theory of plasticity. A variant of obtaining the plasticity matrix using the operations of differentiating the covariant components of the stress tensor with respect to the covariant components of the strain tensor is considered. As an alternative to it, an option has been developed for the formation of a plasticity matrix at the loading step, based on the hypothesis of proportionality of the components of the deviator of stress increments to the components of the deviator of strain increments for three-dimensional bodies. The use of such option of forming a plasticity matrix at the loading step in software systems can significantly simplify the programming process and make it more understandable to potential users of computing systems in the design and reconstruction of technosphere objects and systems.
Study of the antivibration suspended seat oscillations with quasi-zero stiffness effect under sinusoidal excitation
Authors: Korytov M S , Shcherbakov V S , Titenko V V , Pochekueva I E 
Published: May 2021

Abstract
The relevant task of reducing the vibrations transmitted to a human operator of a construction or road vehicle during operating process is accomplished, among other things, by conducting the research on mathematical models. Oscillations simulation of the human operator’s seat antivibration suspension by means of the numerical solution of the ordinary differential equations system remains one of the main methods of the study, used in particular for the discrete mathematical models verification. Therefore, the problem of determining the rational value of the maximum integration step by using the numerical method in solving the systems of the ordinary differential equations describing the operator’s anti-vibration suspended seat oscillations is relevant. A discrete mathematical model of a human operator’s seat performing the forced vertical oscillations during kinematic excitation of base movements was developed through the use of the differential equation of the translational oscillations of mass on a movable base. The prescribed displacements of the seat base are described by the harmonic oscillation equation. The numerical solution of the ordinary differential equations system is carried out via the built-in ode45 function of the MATLAB mathematical modeling system. Moreover, the parameters of the developed mathematical model are described, the calculation scheme and an example of a static force characteristic including the quasi-zero stiffness region in the middle section of the characteristic are given. The determination accuracy of the maximum acceleration of the seat in the steady-state oscillation mode is shown to decrease when the value of the maximum allowable integration step increases. It is recommended to limit the value of the maximum allowable integration step to one hundredth of a second. Besides, the effect of the values duality of the maximum acceleration and maximum internal movement of the seat relative to its own base with small changes in the base displacement amplitude, which must be taken into account in modeling, is also revealed.
Stability investigation of a nonlinear hydraulic actuator in terms of wave processes
Authors: Syrkin V V , Galuza Y F , Kvasov I N , Abramova I A 
Published: May 2021

Abstract
In technological machines for various purposes, hydraulic actuators are widely used, which are constantly being improved in terms of the characteristics of power, speed and accuracy. These parameters must be stable, which requires making certain changes in the design of these actuators that allow them to withstand the operating modes of technological machines in the limits search. The authors consider results of the stability investigation of a nonlinear hydraulic actuator under the action of wave processes in its lines. They propose mathematical models of the wave process, which to some extent reflect its influence on the movement of the hydraulic motor in the form of a damping effect. For a nonlinear hydraulic actuator under the action of wave processes, a mathematical model and the results of the study of this hydraulic actuator are presented in the form of conditions, under which the stability of its operation is ensured.
Experimental study on seismic behavior of gangue concrete frame middle joints with different gangue aggregate replacement rates
Authors: Bai Guoliang , Gu Yu , Liu Hanqin 
Published: May 2021

Abstract
The low-cycled repeated loading experiment was carried out for gangue aggregate concrete middle joints with coal gangue aggregate replacement rates 0, 30%, 50%, 70%, 100%. The experiment was designed to investigate the joint failure modes, hysteretic characteristics, joint deformation and energy dissipation behavior of coal gangue aggregate concrete joints with different gangue aggregate replacement rates. Results show that the mechanical and failure process of coal gangue aggregate concrete frame joints, which is the same as that of normal concrete joint, may be composed of four stages: the initial cracking, the thorough cracking, the ultimate stage and the failure stage. It is found that the gangue concrete joints, with the increase of coal gangue aggregate replacement rate, are inferior to the normal concrete joint in the terms of hysteretic characteristics, joint deformation and energy dissipation behavior.
Optimal control of boiler system based on IoT and energy consumption simulation
Authors: Xianru Wang , Xinmin Zhang , Han Zhu , Xuyun Yu 
Published: May 2021

Abstract
The energy consumption of building heating in China is enormous and reducing heating energy consumption is of great significance to promote energy saving and emission reduction in China. A reasonable boiler heating strategy can effectively reduce heating energy consumption. This paper presents an optimal control method based on the IoT system and an interface that makes Energy Plus in the cloud server work together with the IoT system. The boiler can make corresponding adjustments to the outlet temperature according to weather conditions and other factors to achieve energy-saving. The results show that the intelligent control method proposed in this paper can reduce the boiler outlet temperature by 2-8 °C and can reduce energy consumption by about 15%.