bluuebunny/crossref_metadata_2025_split huggingface dataset:
Physical and mathematical modeling of the moving the raw cotton between directing wall and area ginning seeds
Authors: Ahmedov M , Shoraxmedova M , Tuychiev T , Tashpulatov D , Cherunova I 
Published: December 2021

AbstractIn article are brought algorithm and results brought numerically-experimental studies on qualitative and quantitative estimation of the law of the moving the raw cotton from directing walls outgoing between spiked-drum and netlike surface feeder aside worker of the camera ginning machines. It is known that the uniform supply of raw cotton to the ginning process has a direct impact on the efficiency of the ginning process. In the process of ginning, the cotton is cleaned on the surface of the pile drum and net of the supplier, and the crushed gin comes to the working chamber through the gin. As a result of the rotation of the saw cylinder in the working chamber, the cotton fiber is suspended and the rotation is started. As a result of the circular motion of the raw cotton, a raw material roller is formed. In this process, the actual problem is to ensure that the raw cotton consists of small pieces and is uniform in time and width of the equipment. The Comparison got given on calculation shows that increase the corner will bring about increase the growing forming displacement. Increase of this corner will bring the leaflet of the raw cotton about increase of length free moving.
Pose estimation for the case of prolonged under-ice based AUV
Authors: Frolov D , Polovko S 
Published: December 2021

Abstract
The technological operation of AUV docking is considered. An approach to its solution and modeling is proposed. A system for determining the relative position based on cameras and active-light markers is described. Active markers are offered to improve detection in dark deep water. A system of equations for modeling the dynamics of an underwater vehicle is described and a complete mathematical modeling of the whole pipeline of the positioning system is performed: image synthesis based on scene geometry, position determination based on the solution of the PnP problem, generating control based on synthesized measurements and modelling of the corresponding movement of the AUV. The presented model can be used to test various scenarios for the execution of a docking operation.
Improvement of methods of hydrological forecasting using geoinformation technologies
Authors: Zueva A , Shamova V , Pilipenko T 
Published: December 2021

Abstract
This article discusses the possibility of improving hydrological forecasting methods based on a neural network. The hydrological series, its importance and forecasting features are considered. For hydrological forecasting using the MapInfoProfessional geoinformation system, an electronic map has been developed containing information about the rivers of Russia, as well as gauging stations on the Ob River. The electronic map is the basis for creating a module for short-term hydrological forecasting based on an artificial neural network. The features of a neural network, methods of its training and implementation are considered. The developed artificial neural network is a layer of neurons with a linear activation function and a delay line at the input. To predict the levels of hydrological series, real water levels at gauging stations of the Ob River in the Novosibirsk region will be used. The developed module and its capabilities have been tested. The study was carried out on the basis of models of hydrological series, as well as on the basis of levels of real hydrological series. Based on the study, dependence of the root-mean-square error on the number of previous values of series was revealed. The study also shows that it is possible to use a neural network for the current one-step forecasting of levels of hydrological series in conditions of insufficient information about the runoff region and its characteristics.
Assessment of the position of the project water flow in the lower reaches of hydroelectric facilities, using the example of the novosibirsk hydroelectric power station
Authors: Akhmatova N , Mikhaylova T , Pilipenko T 
Published: December 2021

Abstract
Construction of large hydroelectric complexes on the plain rivers of Western Siberia, such as the Ob, as well as other types of anthropogenic impact (infill development, quarrying of nonmetallic building materials, carrying out track works, laying communications, wastewater discharges, etc.) lead to a change in water and channel regimes, hydrological characteristics, channel deformation in the downstream. One of these changes is the landing of water level in the section of the lower pond of the Ob from the Novosibirsk hydroelectric complex to the mouth of the Tom River, which adversely affects navigable conditions of this stretch, operation of water intakes, port and sluice, and also damages the fish industry. The landing of the water level continues to this day, and in order to maintain the design water level, it becomes necessary to increase navigation releases. The design level was changed several times after the commissioning of the Novosibirsk hydroelectric complex due to its low availability, a further change in the availability will lead to a change in the design level mark, or rather its lowering. Therefore, the purpose of the study is to assess the position of the design flow rate at the established design level and make a forecast of changes in water flow depending on the time that has passed since the start of operation of the Novosibirsk hydroelectric complex, taking into account the impact on the channel, carried out dredging works, as well as other types of anthropogenic impacts.
On the parameterization of phytoplankton primary production in water ecosystem models
Authors: Golosov S , Zverev I , Terzhevik A , Palshin N , Zdorovennova G , Efremova T , Bogdanov S , Zdorovennov R 
Published: December 2021

Abstract
Parametrization of the formation of organic matter in ecological models is traditionally carried out by using the dependence of the Michaelis – Menten – Monod type [Monod, 1942], which describes the growth rate of algal biomass depending on the factor limiting their development. One of the biggest drawbacks of these dependences is the presence of empirical parameters in them, which in a complex way depend on environmental factors and are an individual characteristic of various types of algae. These parameters in the models actually become fitting coefficients that provide the best fit between observational data and modeling results, which does not allow for effective diagnostics and forecasting of the state of aquatic ecosystems. In this work, on the basis of dimensional analysis, a parametrization was obtained that describes the photosynthesis of algae depending on the parameters relatively easily measured in natural conditions - total solar radiation, phytoplankton biomass, and water transparency. Parametrization has been verified according to observations on more than 30 different types of lakes located in different regions of the world. The calculated data are in satisfactory agreement with the data of field observations, both qualitatively and quantitatively. Discrepancies in field and calculated data may be due to the fact that the species composition of algae in lakes of different trophic status is not taken into account, which can lead to errors in assessing the efficiency of using solar radiation. Discrepancies may also be related to the total solar radiation, rather than photosynthetic active radiation, which varies in different geographic and atmospheric conditions. The proposed parametrization can be used in the development of mathematical models of lake ecosystems, as well as to determine the trophic status of poorly studied water bodies.
Seasonal change in heat flux at the water-bottom sediment boundary in a small lake
Authors: Zdorovennova G , Terzhevik A , Palshin N , Efremova T , Bogdanov S , Zdorovennov R 
Published: December 2021

AbstractHeat exchange with bottom sediments is the main component of the thermal regime of ice-covered shallow lakes of the temperate zone, which explains the importance of its study and parameterization for inclusion in numerical models. Circulations arising in ice-covered lakes due to heat exchange with bottom sediments, and existing for several months, can make a significant contribution to the transport of dissolved and suspended particles along the water column. The aim of this work was to study the seasonal variability of the heat flux at the waterbottom boundary in a shallow lake during the under-ice period, including the period of spring under-ice convection. Based on the analysis of data from high-frequency (minute) long-term measurements of water temperature in the bottom area of a small lake in the temperate zone, a wide range of variability of the heat flux across the water-bottom boundary during the winter from minute to daily fluctuations was established. The role of the spring under-ice heating in the change in the heat flow at the water-bottom boundary is shown. It is shown that shallow areas of the lake bottom, falling into the zone of influence of spring subglacial convection, can accumulate heat already at the end of the ice period. The comparison of temperature fluctuations in the deep-water part of the lake and tin he area with depths close to the average is carried out. It is shown that the spectrum of temperature fluctuations has similar periods, however, in time, sharp temperature jumps in different areas of the lake do not coincide.
Investigation of the effects of main geometric parameters and flow characteristics on secondary flow losses in a turbine cascade
Authors: Mesbah M , Gribin V G , Souri K 
Published: December 2021

Abstract
This paper presents numerical simulation results of a three-dimensional (3D) transitional flow in a stator cascade of an axial turbine. The influences of the main geometric parameters and flow characteristics including, the blade aspect ratio, pitch-to-chord ratio, inlet flow angle, and exit Mach number, on secondary flows development and end-wall losses, were studied. The numerical results were validated by the results of experiments conducted in the laboratory of the steam and gas turbine faculty of the Moscow Power Engineering Institute. The maximum difference between computed and experimental results was 2.4 %. The total energy losses decrease by 20 % when the exit Mach number changes from 0.38 to 0.8. Numerical results indicated that the blade aspect ratio had the most effect on secondary flow losses. The total energy losses increase by 46.6 % when the aspect ratio decreases from 1 to 0.25. The total loss of energy by 13.2 % decreases by increasing the inlet flow angle from 60 degrees to 90 degrees. Then by increasing the inlet flow angle from 90 to 110 degrees, the total loss rises by 3.6%. As the pitch-to-chord ratio increases from 0.7 to 0.75, the total energy losses are reduced by 12.2 %. Then by increasing the pitch-to-chord ratio from 0.75 to 0.8, the total energy losses increase by 6 %. As with experimental data, the numerical results showed that the optimal inlet flow angle and relative pitch for the cascade are 90 degrees and 0.75, respectively.
Solving the problem of classification of material properties using a neural network
Authors: Babushkina N E , Lyapin A A 
Published: December 2021

Abstract
The article sets the task of classifying various materials and determining their belonging to a specified group using a recurrent neural network. The practical significance of the article is to obtain the results of the neural network, confirming the possibility of classifying materials by the hardness parameter using a neural network. As part of the study, a number of experimental measurements were carried out. The structure of the neural network and its main components are described. The statistical parameters of the experimental data are estimated.
Methods for solving the nonlinear equilibrium equation of a compressed elastic rod
Authors: Peshkhoev Isa M , Kanygin Georgy I , Fatkhi Denis V 
Published: December 2021

Abstract
A nonlinear boundary value problem on the equilibrium of a compressed elastic rod on nonlinear foundation is considered for cases of free pinching or pivotally supported of the ends. The problem is written as a nonlinear operator equation. Numerical and analytical methods for solving nonlinear boundary value problems are discussed: The Newton-Kantorovich method and the Lyapunov-Schmidt method. We also consider a problem linearized on a trivial solution (the eigenvalue problem), which has an exact solution (Euler) in the case of a hinge support, and for the case of pinching the ends of the rod, the solution formulas are obtained in the works of A. A. Esipov and V. I. Yudovich. The eigenvalue problem is also solved by numerical method. To determine the equilibria of a nonlinear boundary value problem for a given value of the compressive force, it is proposed to apply the Newton-Kantorovich method in combination with the numerical methods, using as initial approximations the asymptotic formulas of new solutions found using the Lyapunov-Schmidt method in the vicinity of the critical value closest to the current value of the compressive load. Numerical calculations are performed and conclusions are drawn about the effectiveness of the methods used.
Mathematical modeling of stress-strain state of the nodal joint of wooden beams
Authors: Sergeev M S , Lukin M V , Strekalkin A A , Roshchina S I 
Published: December 2021

Abstract
The article presents a study of the joint of wooden beams on a new type of aluminum composite connector. For the numerical experiment, beams with a cross-section of 150x220(h) mm made of solid wood were selected. The beams were connected at the same level in a perpendicular direction to each other. The connecting connectors were made of two types of alloys: 7075 T6 and 6061 T6. The experiment was carried out until the joint was completely destroyed under static load. The elastic operation of the node for different types of connectors under study was maintained until the load of 50… 70 kN, after which there was a sharp increase in the deformations of the beams. Conducting a numerical study of the elements of wooden structures made it possible to predict their behavior most accurately in real operating conditions.
Mathematical modeling of mechanical properties of vibro-centrifuged fiber-reinforced concrete of variatropic structure
Authors: Shcherban’ E , Beskopylny A , Mailyan L , Stel’makh S , El’shaeva D 
Published: December 2021

Abstract
Today, one of the most relevant areas in the construction industry, linked to the requirements and provisions of the Strategy of Scientific and Technological Development, and in accordance with the priority areas of science and technology development, is the development and improvement of low-material, low-energy and low - resource-intensive technologies for the manufacture of concrete and reinforced concrete products and structures. In this regard, the technology of vibrocentrifugation, which allows to obtain concrete with an improved variatropic structure, is quite promising. In this work, the influence of the design parameters of the technological equipment and the parameters of the centrifugation modes on the integral strength characteristics of vibrocentrifugated fiber concrete was evaluated. In total, 13 samples of the annular section were manufactured and tested. Calculations of the integral strength characteristics of vibrocentrifugated fiber concrete depending on the height of the technological protrusions of the clamps and the angular rotation speed were performed by the method of orthogonal composite planning of the 2nd order using the MathCAD program. The mathematical method of planning the experiment is aimed at creating mathematical empirical models that determine the influence of the incoming variable factors on the strength characteristics. Thus, according to the results of experimental studies, the optimal height of the technological protrusions and the angular speed of rotation were determined. Thus, further regulation of technological factors in the manufacture of vibrocentrifugated products and structures will allow us to obtain the most effective ring-section structures with enhanced variatropy.
Simulating Nonlinear Dynamics of a 3D Crystal Lattice of Metals
Authors: Semenov A S , Semenova M N , Bebikhov Yu V , Zakharov P V , Korznikova E A 
Published: December 2021

Abstract
Oscillations of crystal lattices determine important material properties such as thermal conductivity, heat capacity, thermal expansion, and many others; therefore, their study is an urgent and important problem. Along with experimental studies of the nonlinear dynamics of a crystal lattice, effective computer simulation techniques such as ab initio simulation and the molecular dynamics method are widely used. Mathematical simulation is less commonly used since the calculation error there can reach 10 %. Herewith, it is the least computationally intensive. This paper describes the process and results of mathematical simulation of the nonlinear dynamics of a 3D crystal lattice of metals using the Lennard-Jones potential in the MatLab software package, which is well-proven for solving technical computing problems. The following main results have been obtained: 3D distribution of atoms over the computational cell has been plotted, proving the possibility of displacement to up to five interatomic distances; the frequency response has been evaluated using the Welch method with a relative RMS error not exceeding 30 %; a graphical dependence between the model and the reference cohesive energy data for a metal HCP cell has been obtained with an error of slightly more than 3 %; an optimal model for piecewise-linear approximation has been calculated, and its 3D interpolation built. All studies performed show good applicability of mathematical simulation to the problems of studying dynamic processes in crystal physics.
Numerical analysis of shear interaction of an underground structure with soil
Authors: Rikhsieva B B , Khusanov B E 
Published: December 2021

AbstractA soil layer behaviour under the shear interaction of an underground structure with soil is studied. Structural failure is considered under conditions of strained soil, and complete cohesion is assumed at the underground structure-soil contact boundary. The Finite Difference Method is used to numerically investigate the process of the structure-soil shear interaction under consideration. The main attention is paid to the adequacy of the conditions of soil-structure interaction, and to the strain state of the near-contact soil layer around the underground structure. The results are plotted and analysed. From the results obtained, the existence of a near-contact soil layer is shown; the use of the condition of complete cohesion is justified considering the structural failure of soil under conditions of complex interaction; the possibility to determine the thickness of the near-contact soil layer and of the layers with the respective degrees of structural failure is shown.
Main rotor blade modeling approaches comparison. Finite element and Craig-Bampton methods
Authors: Borisenko V , Leoro J , Didenko A 
Published: December 2021

Abstract
The paper focuses on the helicopter main rotor blade FE model. And the main goal is to prove the feasibility of the helicopter main rotor MBD model in calculations of blade deformation as a result of applied aerodynamic forces. FE model is used as a basis for two different computational methods. A mathematical approach in the MBD based on the Craig-Bampton method on the one hand. And finite element model on the other hand. The results of high-frequency blade rotations are obtained. Calculations of these models are compared in order to determine the best method for modeling a linear-elastic blade. By the results, it is necessary to consider the preloaded state of the blade when using the Craig-Bampton method approach. The comparison of blade nodes displacements at various external conditions for both models are given. The influence of rotor MBS model damping parameters on the amplitude of blade oscillations under sinusoidal action is considered.
Mathematical modeling of production process using cluster analysis methods
Authors: Dolaeva A R , Medvedeva T A 
Published: December 2021

Abstract
Manufacturing process management is a complex problem characterized by decision-making throughout the entire production process and is reduced to finding the best set of possible (alternative) in terms of some criterion or criteria for the use of available resources. The goal of the production process optimization is to analyze a set of alternative production options in complex systems and to determine the most rational possible state depending on the selected management strategies. The system contains many connections between elements and is influenced by random factors. It is not possible to create a real model for the system that is described analytically, but it can be investigated by using simulation modeling. In the mathematical modeling of the production process cluster analysis methods are used which allow to process a large amount of data from all possible states of the system and divide them into similar aggregates according to several characteristics. The analysis of the formed groups is carried out and the regularities that have the most significant impact on the occurrence of states into clusters are revealed.
Digital transformation of machining workshop’s manufacturing system
Authors: Reshetnikova E , Bochkarev P , Gumarov G 
Published: December 2021

Abstract
The article proposes the method of intellectualization workshop’s manufacturing system. The digital technology is widely developed today so intellectualization of manufacturing system is relevant today. The use of AMT-supported manufacturing process in manufacturing system contributes to obtaining advantages in material and financial terms and reducing the cost of time resources.The use of automation technology in workshop process assumes cutbacks to its funding and ensures its digitalization. The digitalization is aimed at eliminating production errors and shortcomings already at the design stage of the production process. In consequence of this technological defects of products are reduced and the technological process is well organized. The use of an innovative approach to the development of the technological process of manufacturing products allows reducing time resources and increasing technical efficiency. Actualization of the suggested approach provided with system of computer-aided planning multiproduct technologic process. This system is developed by the authors and aimed at planning the intelligent product campaign. The presented algorithmic and software support for the formation of a rational set of control-and-measuring tools provides the development of a rational technological process for manufacturing a product and automation of the production’s technological preparation.
Choice of cargo delivery option in multimodal connection based on reinforcement learning
Authors: Badetskii A P , Medved O A 
Published: December 2021

Abstract
The article discusses the issues of choosing a route and an option of cargo flows in multimodal connection in modern conditions. Taking into account active development of artificial intelligence and digital technologies in all types of production activities, it is proposed to use reinforcement learning algorithms to solve the problem. An analysis of the existing algorithms has been carried out, on the basis of which it was found that when choosing a route option for cargo in a multimodal connection, it would be useful to have a qualitative assessment of terminal states. To obtain such an estimate, the Q-learning algorithm was applied in the article, which showed sufficient convergence and efficiency.