bluuebunny/crossref_metadata_2025 huggingface dataset:
Modern Electromagnetic Field Theory and Its Application in Future Wireless Communication
Authors: Cui Wuwei
Published: December 2022

With the advent of the 5G era, more and more technologies in life are applied to the technological development and theory of antennas. Waveform constraints. These basic applications are obtained due to the natural seismic source and the continuous arrangement and combination of arrays. In this article, we first discuss the spherically symmetric electric field distribution of antenna elements in space, and then discuss the influence of a circular array on the electromagnetic intensity of the space radiated field. At the same time, the basic characteristics of waveform restraint, array radar and array telescope are discussed. Afterwards, from a theoretical point of view, the physical properties and radiation characteristics of the near-field induction field and radiation field of the factory around the vibrator were analyzed quantitatively and qualitatively. Later, I discussed the relationship between an annular array and the eddy current. Through theoretical derivation and excitation factors, we used the original radiation equation to derive the Bessel function, and used a computer to make a simulation to explore the factors that can affect the array radiation.
Process Optimization of Single-Step Photolithography
Authors: Zhang Junyang
Published: December 2022

Due to the precision and sizing requirements of popular semiconductor devices nowadays, thickness control and uniformity optimization of the photoresist during the photolithography process are thought to be critical issues for process engineers to consider. In this paper, the parameters affecting photoresist thickness are thoroughly analyzed and an economic and novel approach improving uniformity during spin coating is presented. In the Integrated Nanosystems Research Facility at the California Institute for Telecommunications and Information Technology (Calit2), 8 silicon wafers were coated with a positive photoresist named Shipley 1827 for this purpose. At the end of this paper, the author concludes several essential but easily ignored factors that can affect the uniformity and thickness of the photoresist. By following the given rules, high quality single-layer silicon wafer can be coated at ease.
Introduction to Mirror Symmetry in Aspects of Topological String Theory
Authors: Chen Shu
Published: December 2022

Under the compactification by the Calabi-Yau threefold, the string theory shows there is duality called mirror symmetry, which implies there is an isomorphism between two string theories under the compactifications of two topologically different internal manifolds. By twisting the topological string theory in two methods, the twisted theories named A-model and B-model have an isomorphism to each other under the mirror symmetry.
Mechanical Design and Analysis of a 3D-printed Planar Compliant-Rigid Hybrid Robot Prototype
Authors: Wang Yuxuan
Published: December 2022

In our daily life, rigid-body robots have been widely encountered in many applications, such as industrial robots working in the assembling stream and medical robots for healthcare of patients. Rigid-body robots nowadays achieved great success in load carrying and motion compensation. However, rigid-body robots have strong stiffness during interaction with objects and may not suitable for human utilization. Compliant robotics, on the other hand, is flexible and can modulate stiffness and deformation, resulting comfortable interaction for human bodies. Motivated by taking advantage of both rigid-body robots and compliant robots, in this paper, the design of a planar robot prototype with a hybrid compliant-rigid structure is presented. Forward and inverse kinematics are analyzed for such a compliant-rigid robot. Simulation presents the feasibility of trajectory tracking on such robot for path planning tasks. The designed robot prototype is further manufactured by 3D-printing technique.
A Optimization Study on the Upper Limb Exoskeleton based on Beetle Antennae Search
Authors: Jiang Yingnan
Published: December 2022

Paralyzed exoskeleton robots of upper limb can be used to help patients with paralysis or stroke to carry out rehabilitation training, and it has attracted extensive attention because of its standard and effective help to rehabilitation. However, the exoskeleton robots are coupled highly-nonlinear systems, which is difficult to solve it through the traditional analytical method. The most common method is to obtain the analytic joint angles from joint velocity spaces by using the pseudo-inverse-based calculation method, which may lead to more calculation cost and lower system accuracy. In this paper, a motion planning method based on beetle antenna search algorithm(BAS) was improved. The proposed method greatly enhance the control accuracy of the system, and also improves the efficiency of the original algorithm. The simulation results show the effectiveness of the improved motion planning method.
The Review of Types of Radiation Resistance Materials and Proposed Experiments
Authors: Su Yuexin , Ye Yuting
Published: December 2022

In the last decade, the development of irradiation materials has greatly promoted the progress of nuclear technology. Therefore, the application of radiation resistance materials and the understanding of its principle are very important. This paper summarized several irradiation resistance materials to reflect the type, principle, calculation and its application in nuclear reactors. For example, the atoms of the alloy interfere with each other to form a material more resistant to radiation than pure nickel under temperature changes. And the organic radiation resistance material glass fiber reinforced plastics (GFRPs) can resist the gamma rays generated in nuclear reactors. The radiation resistance principle of magnesium aluminate defect clusters will also be discussed. In addition, we have designed an experiment to measure the energy-loss of neutron irradiation to test the material’s neutron resistance ability.
A high precision phase extraction method in heterodyne interferometer based on FPGA
Authors: Deng Wen , Peng Xifeng
Published: December 2022

The high-precision phase extraction method directly determines the final measurement performance of the heterodyne laser interferometer. This paper proposes a digital quadrature phase-locked (DQPL) method with sub-nanometer precision based on FPGA hardware and compiled on the LABVIEW FPGA platform. DQPL method can accurately extract the phase difference of the two optical signals in the heterodyne laser interferometer. The validity and stability of the method have been verified by simulations and experiments. The experimentally obtained measurement resolution is 0.074 nm, and the measurement standard deviation obtained by the Monte Carlo method is 0.22 nm.
Improved performance of nafion membranes by blending ultra-high molecular weight polyvinylidene fluoride
Authors: Feng Chao , He Weidong
Published: December 2022

Proton exchange membrane (PEM) is developing towards thin thickness and high mechanical strength for extraordinary performance proton exchange membrane fuel cells (PEMFCs). However, the commercial membrane such as Nafion can hardly satisfy the practical application of PEMFCs because of high gas crossover and low mechanical strength when the thickness is less than 20 μm. Here, a reinforced composite membrane (denoted as P110-PFSA) was synthesized by blending poly(vinylidene fluoride)(PVDF) featured with high molecular weight of Mw= 1100000 g mol-1 into perfluorosulfonic acid resin (PFSA). The P110-PFSA with the thickness of 15 μm exhibits tensile strength of over 33 MPa because the PVDF with high molecular weight forms a higher density of hydrogen bonds with PFSA, resulting in a reinforcement of the bonding strength between PVDF and PFSA. H2/O2 fuel cell performance with the P110-PFSA shows more than 1170 mW cm-2 fed with H2 at 70 °C and 100% RH much better than that with Nafion 211. Direct methanol fuel cell power densities of the blent PEM are 92, 61, 50, 28 and 15 mW cm-2 fed with 2, 6, 10,16 and 20 M methanol solution respectively at the anode.
Research on PID control of electric traction DC motor speed based on MATLAB
Authors: Wang Huarong , Yan Qiyan
Published: December 2022

With the development of science and technology, digital control systems are more widely used, which is more conducive to the development of intelligent power locomotives. In the speed control process of electric traction DC motor, considering the stability, rapidity, accuracy and other requirements of speed control, digital position type PID control strategy is adopted.This study first models the power traction DC motor and analyzes the performance of the system. In order to improve the performance index of the system, a digital PID control strategy is adopted.MATLAB simulation results show that the controller has good speed and stability for the speed control of electric traction DC motor.
Investigation of the surface recombination rate in polycrystalline films from the A6B6 compound by the MW-PC method
Authors: Alimov N E , Vaitkus J V , Otajonov S M , Botirov K
Published: December 2022

In this article, the surface recombination rates in polycrystalline CdTe films obtained on oxidized substrates are studied. The results of the corona discharge effect on the CdTe-SiO2–Si-Al structure are presented. In this case, in the static mode, a shift of the short-circuit current spectra to the short-wave region was observed. To analyze the shift of the short-circuit current spectra, the method of microwave probe photoconductivity (MW-PC) was used and non-contact registration of decay transients for excess carriers was carried out. Considering that for CdTe in the wavelength range of about 800–1000 nm, the absorption coefficient increases sharply with the excitation photon energy at the absorption edge. It was found that the surface recombination rate was estimated at 19 ns. It has been determined that the filling of surface traps in CdTe leads to a decrease in the effect of surface recombination.
Method of manufacturing working surfaces of ironing tables for wet-heat works of garments from composite materials
Authors: Nutfullaeva L N , Nutfullaeva Sh N , Tashpulatov S Sh , Muminova M S , Sayfullaeva L M
Published: December 2022

The article studied the components, types and properties, as well as the classification of composite materials. The direction of use and methods for obtaining new structural materials are considered. The developed new technology for the production of composite materials is described, which is used for the manufacture of parts for ironing equipment of sewing enterprises. The method of forming the working surface of ironing tables from a new composite material is substantiated.
Graphene nanotechnologies: experience in using the mechanical and electrical properties of graphene
Authors: Andreev D V
Published: December 2022

This article is about the unique properties of graphene, which can make a breakthrough in various fields. Graphene is the material of the future for creating various technologies. The article analyzes the advantages and disadvantages of this component. In addition, the latest achievements of Yakutia in the field of graphene-based materials research are described, mainly using the mechanical and electrical properties of graphene.
Mathematical model of the process of vertical drying of raw cotton in the hot airflow
Authors: Safarov Nazirjon , Mukhammadjanova Iroda , Kabulov Mukhammadali
Published: December 2022

The article covers theoretical studies that have been carried out on the development of the mathematical model of the process of drying raw cotton, considering the laws of aerodynamics in a vertical cylindrical drying device using a hot airflow obtained using alternative energy sources.
Control algorithm for decision making in multi-criteria optimization problems
Authors: Grishko A K
Published: December 2022

The main feature of the multi-criteria optimization of the design processes of complex electronic devices is that they are all interconnected, heterogeneous in nature and, as a rule, non-linear. That is, by changing some of them by varying the corresponding parameters, we inevitably change other parameters of the system, and not always in the right direction. The purpose of the work is to propose a way to organize the procedure for finding the optimal solution to multicriteria design problems. When developing and creating new schemes, structures and systems, the task of determining the optimal values of the parameters of the designed technical device or system is reduced to the task of finding the extremum of a certain function, called the quality function. Usually, it is a non-linear function of many independent variables, which, as a rule, cannot be investigated by analytical methods. In this situation, it is advisable to search for a solution to the problem using special algorithms. At the early stages of designing complex radio electronic devices, an algorithm for finding the optimal solution based on the application of search optimization theory methods is proposed. The paper describes the procedure for finding the optimal solution, the distinctive feature of which is that during the search for a solution, information is accumulated and a search direction vector is constructed. This vector offers options for changing weights for subsequent search procedures. The algorithm developed on its basis is used in the information system for the complex analysis of the designs of radio-electronic facilities. The use of random search provides the algorithm with global properties, reduces the number of objective function calculations by one step, which is especially noticeable with a large number of optimized parameters. Allows you to quite simply include any restrictions on the set of valid values of the vector of optimized parameters, which is not always possible when using regular search methods. The proposed algorithm is simply tuned to search for a global extremum by selecting the appropriate parameters. For each specific case, there are some optimal ratios of the values of these algorithm parameters, which, when searching for a solution, reduce the number of working steps. The developed algorithm is less critical to the optimal values of its own parameters, which makes it much easier to tune it when solving practical problems of optimizing design processes.
Single channel queuing system utilization factor model
Authors: Zyulkov Alexander , Kutoyants Yury , Perelevskiy Svyatoslav , Korableva Larisa
Published: December 2022

Under the assumption of a low intensity of the flow of incoming requests and a high speed of their service, the M|M|1 system utilization factor model is considered. It is estimated for a small part of the observation time. Approximate relations are obtained for the system utilization factor. Its simple probabilistic model in the form of a probabilistic mixture is proposed. A comparison with the results of simulation is carried out.
Modified discrete phase numerical model for calculating ultrasonic coagulation in Eckart flows
Authors: Shalunov A V , Golykh R N , Khmelev V N , Nesterov V A
Published: December 2022

One of the most effective methods for trapping aerosol particles is the preliminary combination of particles into agglomerates under the action of high-intensity sinusoidal ultrasonic (US) oscillations (ultrasonic agglomeration) for further trapping of coarse particles by traditional methods (inertial or gravitational settling, filtration through a porous material, etc.). To date, the effectiveness of ultrasonic agglomeration has been repeatedly proven for particles larger than 2.5 μm. However, ultrasonic agglomeration, based on the known mechanisms of particle interaction, is not very effective when exposed to particles smaller than 2.5 μm and especially less than 1 μm. At the same time, the possibilities of a linear acoustic field are well studied today and it has been established that exposure to a linear acoustic field does not provide effective coagulation of PM2.5 particles. And with an increase in the sound pressure level of a linear acoustic field, coagulated particles (especially when it comes to solid particles) begin to break down. Therefore, the authors proposed to use nonlinear effects, which consist in the formation of vortex acoustic (Eckart) flows that can cause a local increase in the concentration of particles and, consequently, an increase in the efficiency of coagulation. It has been established that the formation of vortex acoustic sweats in the resonant gap can additionally increase the efficiency of ultrasonic coagulation by at least 1.5 times.
Investigation of the possibilities of surface hardening of heavily loaded metal elements made of carbon steels for various purposes
Authors: Moldahmetova A E , Sarsembaeva T E , Vasil’ev I M , Zagidullin R R , Sabitov L S , Nurullin A F , Novikov S V
Published: December 2022

The interaction of the wheel and the rail, being the physical basis for the movement of trains, determines not only such important technical and economic indicators of railway transport as the weight of trains and their speed, the reliability and operational life of wheel sets, but also the basis of the foundations of railway operation - the safety of train traffic. Therefore, studies of the problems of interaction of the wheel-rail friction pair are relevant and in demand not only within the framework of a particular wagon or locomotive depot, but also in the country’s railway transport as a whole. In this regard, it is important to note that one of the main and most loaded elements of the undercarriage of locomotives and wagons that directly interact with the rails are railway wheels. An important factor in the development and implementation of new surface hardening technologies is: firstly, rising prices and corresponding costs for the production of metal products for wheels with high energy consumption, secondly, increasing costs for spare parts, maintenance and overhaul of wheel sets; thirdly, the rise in prices for energy carriers and transportation costs for their delivery; traditional heat treatment is almost impossible to achieve.
Investigation of mechanical processing during milling
Authors: Khamroev Khamza , Savriev Yuldosh , Buronov Sunatullo , Turaeva Umida
Published: December 2022

The development of the engineering industry is determined by the efficiency of the technological processes used in it. In a market economy, improving the quality of products and reducing their costs increase commodity competitiveness and lead to further development of production. The quality and cost of the product produced, the simplicity of its design, labor productivity. On the basis of vibration diagnostics, it was found that the average signal amplitude decreased with increasing force and rigidity as the center of the workpiece was approached, as well as a decrease in the vibration frequency, which had a positive effect on the quality of processing and reduced tool wear.
Metallographic properties evaluation of the specimens obtained by the vibratory method (cast iron ISO 400-12)
Authors: Ojeda Pardo F R , Sánchez Figueredo R P , Belette Fuentes O , Quiroz Cabascango V E , Mosquera Urbano A P
Published: December 2022

The objective of this research is to evaluate the metallographic properties to obtain cast iron with nodular spherical graphite ISO 400-12 by “In mold” modification using the vibratory method. To carry out the experiments, a model was prepared to reproduce the specimens used, according to the ASTM A0536-84R04 standard for the certification of the quality of cast iron with spherical nodular graphite. The pouring temperature levels were adapted to the wall thickness of the specimens. Vibration frequency (65 Hz, 70 Hz, 75 Hz), pouring temperature (1450°C and 1425°C) and mass of nodulizing alloy FeSiMg (NODULAN II) (189.98 g; 170.99 g; 151.99 g), calculated by the traditional method, were set as independent variables. The applied vibratory method caused changes in the morphology of the metal, as high spheroidization was obtained for all levels of modified alloy mass and smaller nodules (from 40 μm to 60 μm in diameter) were achieved. The tensile strength and relative elongation of the specimens obtained by the vibratory method were similar to the international standards for this type of casting and higher than the castings with nodular spherical graphite obtained under static conditions. Finally, the standard specimens (static method) and the specimens obtained by the vibratory method were obtained, and the metallographic and mechanical properties tests established by the international standards were carried out.
Thermal insulation of engineering structures with mineral wool based on basalt fiber
Authors: Koroli M A , Ivanisova A R
Published: December 2022

The most vulnerable link of central heating systems are heat pipelines. Steam and condensate pipelines devoid of thermal insulation are a constant source of heat loss, which can be easily eliminated. In most cases, the thermal insulation of all heated surfaces does not present significant difficulties. There may be situations when the insulation was removed during maintenance or repair and not restored at the end of the work. Removable thermal insulation elements of valves and other devices may also be missing. To ensure the economic efficiency and reliability of heat supply, it is necessary to intensively modernize heating networks. The most effective way to increase the energy efficiency of engineering structures is the use of modern structural solutions using thermal insulation materials. In addition, it allows you to reduce operating costs, that is, to achieve significant savings in fuel resources. The economical efficiency of district heating systems at the current scale of heat consumption largely depends on the thermal insulation of equipment and pipelines. The struggle to reduce transport heat losses in pipelines is the most important means of saving fuel resources. The paper considers the possibility of improving the energy efficiency of engineering structures through the use of modern structural solutions using thermal insulation materials based on basalt fiber.
Technological equipment for foundry production, efficiency and safety
Authors: Kinev E S , Tyapin A A , Panteleev V I , Pervukhin M V , Bezrukikh A I
Published: December 2022

The article discusses the results of the development and research of controlled electrical preheating of casting troughs and intermediate tanks in the system of transport trays for pouring aluminum melt. Electric heating contributes to high-quality and safe pouring of the melt in the cold shop. The heating of the casting track links eliminates the possibility of an explosion when the melt contacts water or ice, and also maintains the fluidity of the metal and limits the temperature gradient in the melt. Evaluation of the efficiency of the heater system was carried out on the basis of mathematical modeling of thermohydrodynamic processes in the melt. Acceptable characteristics of the section of the trays were determined to improve the distribution of metal by the melting and casting complex. To ensure the electrical safety of the equipment, it is proposed to power the heaters at a reduced voltage. Changing the intensity of heating is implemented by switching the windings of a group of power transformers from a delta connection to a star connection. Preheating controls are built in the form of a relay-contactor subsystem integrated into the microcontroller control system of the foundry complex.
Monitoring of the residual life of galvanic batteries
Authors: Emets S V , Krasnov A N , Yu V Kalashnik , Prakhova M Yu
Published: December 2022

The development of distributed automation systems built on the use of wireless communication channels has led to an increase in the role of autonomous power systems. These systems use so-called CCS - chemical current sources, both rechargeable (accumulators) and non-rechargeable (batteries, or galvanic batteries). Depending on the purpose and operating conditions, the battery life of the same type may be different, and for some automation systems, knowing its current value is critical. An example of such a system is an automated telemetry system for drilling oil and gas wells, in which its constituent modules are powered from an autonomous source based on lithium-thionyl chloride cells. A feature of the system is the presence of several modes of operation, which differ significantly from each other in duration and energy consumption. The article proposes an algorithm for monitoring the residual resource of galvanic batteries, which provides a correct account of the consumed resource for modes of any duration. A feature of the algorithm is the accounting of the consumed resource through the formation and calculation of conditional single portions, the so-called basic electric charge. For this, a double integration of the voltage proportional to the consumed current is used. Checking the proposed algorithm for monitoring the residual life of the CCS in the program for modeling electrical circuits Electronics Workbench confirmed its feasibility.
Effect of laser treatment on zinced steel surface wettability and corrosion resistance
Authors: Dasaev M R , Kalakuckaya O V , Trushin E S , Grigoriev S V , Ryzhenkov O V
Published: December 2022

The paper presents the results of experimental studies to determine the effect of surface treatment of galvanized steel using laser equipment on wettability properties and corrosion resistance. It is shown that laser texturing of the roughness on the zinc layer contributes to the achievement of the hydrophobic state. It is noted that during ablation and discontinuity of the zinc layer on the steel surface, the hydrophobic state is achieved only due to the formation of molecular layers of the surfactant. An increase in the corrosion resistance of galvanized steel was achieved by activating the zinc layer due to laser texturing of the surface at a radiation density of 20 and 35 J/cm2. With ablation and discontinuity of the zinc layer on the steel surface, the corrosion resistance is significantly reduced.
Improving the quality of bog oak boards using microwave drying chambers
Authors: Shamaev V A , Medvedev I N , Parinov D A , Russu A V , Garkusha O S
Published: December 2022

The stocks of bog oak taken from the bottom of reservoirs are increasingly used to preserve growing valuable species of wood, primarily oak. English oak (Quercus pedunculata Ehrh.) is a hard-drying species. Drying modes of oak boards have been well developed for both convection and microwave drying. The interest in bog oak, rose out from water bodies, sharply increased, but it turned out to be impossible to dry it using known methods other than microwave drying. Cracking defects are 70% at a thickness of 30 mm and 100% at a cross section of 60 mm. The article analyzes the results of bog oak drying in laboratory-type microwave chambers. The distance between magnetrons was 0.5 m, and a length of boards was 1.2 m. A semicommercial plant with a loading volume of 2 m3 and total power of 30 kW was used. Total drying time for boards with a total loading volume of 0.2 m3 was from 3 to 5 days. Cracking defects reduced to 20% for a thickness of 30 mm and to 32% for a thickness of 60 mm (with additional treatment by 40% carbamide solution). Board warping was not noticed.
A comprehensive study of shells with corrugated inner surface
Authors: Yakovlev S S , Karkach L V , Galitsina K A
Published: December 2022

This paper presents the results of a comprehensive assessment of the manufacture of pipes with corrugated inner surface. It examines the technological force, the stressed and deformed states, the probability of defects during corrugation of the pipe at different depths with the help of a rotating working mandrel and the plastic deformation caused by it. The analysis was performed using special QForm software. The study provides the graphs of force, distribution of stress and strain intensity and the probability of defects occurring in the part during corrugation.
Computational study of gas flow characteristics when using intra-nozzle interceptors for thrust vector control
Authors: Brykov N A , Tischenko K A
Published: December 2022

This article proposes the use of cylindrical nozzle interceptors (probes) as an alternative method of rocket engine thrust vector control, which can replace traditional thrust vector control systems. The objective of this paper was to perform a three-dimensional CFD simulation of the gas flow in a rocket engine nozzle with a rod interceptor taken out of the wall without secondary injection, analyzing the calculated flow data and estimating the lateral force. The simulations will be performed in steady-state mode. In the CFD simulations, velocity distribution contours were obtained on the symmetry plane for all positions and values of the interceptor height.
Modelling vortex ring formation, discrete phase intake and transport via formed structure
Authors: Emelyanov V N , Kapranov I E
Published: December 2022

Vortex ring formation using cylindrical tube with open section considered in present research work. Injection of discrete phase in form of solid particles into formation area leads to its involving and further transportation via vortex ring. Numerical simulation in presented work used as main tool. Fluid considered as viscous, incompressible and described by Navier-Stokes equations. Drag law for sphere particles is used. Vortex ring generation factors including geometry and operating parameters as well as location and size of injection area are subjected to analysis.
Focusing of a compression waves in a toroidal bubble cluster
Authors: Gimaltdinov I K , Nasyrov A A , Gimaltdinova A A , Gizzatullina A A , Galimzyanov M N , Yu Kochanova E
Published: December 2022

The dynamics of waves in a cylindrical channel containing a toroidal bubble cluster is studied. It is shown that the existence of a cluster cause of focusing of waves in the channel. The dependence of the maximum amplitude of the compression wave formed in the domain on the parameters of the domain, as well as on the amplitude of the initial pulse, is analyzed.
Soil decompaction of pavement base observed in space and time
Authors: Borovik Vitaly S , Borovik Vitaly V , Borovik Anastasiy V , Lepekhina Daria M
Published: December 2022

It was found that at the time of completion of soil compaction it has content moisture of ∼ 4-8% and, therefore, the osmosis coefficient in the initial period of road use is minimal. The osmosis is mutually eliminated by antiosmosis, which determines the duration of the osmotic period. It was established that the magnitude of the osmosis coefficient is influenced by factors that also affect the parameters of the electric double layer: coefficient of soil compaction, mineral composition, type of exchangeable cations and the concentration of pore solution. The increased density of soil improves the capillary properties of soils and enhances the process of heat and moisture transfer, which makes it possible to make an assumption about the further development of osmotic processes with their subsequent stabilization, provided there are no additional sources of moisture.
Smart device for capturing and transferring honeycomb core for a safe technological cell for cutting honeycomb blocks
Authors: Pikalov Ya Yu , Shtabel N V , Talai E P , Saramud M V
Published: December 2022

The article contains a description of the developed design for the capture and transfer of workpieces from cellular fillers. The capture consists of 3 parts: a vision camera, the image from which is affected in order to determine the optimal points for attaching elements; device for inserting/removing fasteners, detection of electromagnetic and spring-loaded pressing plate; a device for carrying workpieces by assembling fasteners in them. This one was built and tested using the KUKA KR6 R900 robotic arm.
Improving the efficiency of foundation construction in permafrost conditions on the example of the use of geopolymer materials
Authors: Subbotin A S , Kravchenko A A , Dmitrienko A A
Published: December 2022

The development of the natural resources of the North and territories with permafrost is an urgent task for countries located in the northern regions, the solution of which is complicated by extreme climatic conditions. Competent arrangement of the base under any structure is an extremely important task, which is solved only by experienced and qualified specialists. This article describes models with the presented optimal methods and technologies for strengthening and strengthening soils and foundations during the construction and reconstruction of construction projects in the Far North using modern material - cryogel.
Research of the effect of the properties of water-oil emulsions on the work of centrifugal electric pumps
Authors: Sattorov Mirvokhid , Adizov Bobirjon
Published: December 2022

In this article, the formation of highly mineralized water-oil emulsions in Uzbekistan, the complexity of their composition, and the effect of their physical and chemical properties on the operation of centrifugal electric pumps used for the extraction and transfer of this type of oil are described. As the period of use of wells increases, the degree of hydration of the well product also increases, which, in turn, complicates the work of centrifugal electric pumps.
Automation of production mechanisms using energy-efficient asynchronous electric drives based on intelligent converter technology
Authors: Pulatov A A , Shaimiev M F , Mirsaidov U M
Published: December 2022

The article presents a comparative analysis of modern energy-efficient asynchronous electric drives. The differences and similarities of both electric drives are given. The algorithm of operation of an energy-efficient asynchronous electric drive of a pumping station is given.
Study of the issues of determining the parameters of the flexural rigidity of saw working bodies
Authors: Muradov Rustam , Abduvakhidov Mubashirkhon , Abduvakhidov Mutakhhirkhon
Published: December 2022

The article investigates the issue of determining the flexural rigidity of a gin saw cylinder formed by tying onto a shaft a package of disks having the same thickness at different diameters and compressed by a longitudinal compressive force. The stated problem is solved on the basis of the general rules of theoretical mechanics and force analysis. Due to the lightening of the elements of the saw cylinders, its design is improved, the general functions of the bending rigidity of the saw cylinder, the thickness of the elements, the magnitude of the friction force between them are obtained. A method and device for assembling saw cylinders has been developed, which makes it possible to increase in the consumption of saws and gaskets by a value limited by the strength only to the impact of the shaft and by regulating to increase in dynamics with a high probability.
Entropy determination in the problem of the analysing an electrical network state under the condition of independence of functioning of its elements
Authors: Dulesov A S , Dulesova N V , Karandeev D Y , Bazhenov R I , Karandeeva I Y
Published: December 2022

The possibility of applying the measure of information uncertainty (entropy) in structural reliability analysis of electricity distribution networks is assessed. The essential factors influencing the process of reliability analysis and related to the presence of information uncertainty are highlighted. The peculiarities of reliability analysis in network designing and operation, when it is required to estimate the state of elements and choose the efficient structure of a network are considered. The opportunities and limitations in the application of existing methods of structural reliability analysis are evaluated; it proves the importance of information uncertainty measurement. The conceptual apparatus of entropy includes the mathematical procedure of its calculation. Fail-safe operation probability and probability of network element failure are taken as reliability index. The mathematical expressions proposed for calculating entropy are applicable when there are two independently functioning network elements, each of which will be able to be in one of two states with a fraction of probability: operable and non-operable. The obtained results allowed identifying the more reliable elements/objects. The application of the proposed mathematical procedure allows to compare network elements with each other through the value of entropy and to choose the most reliable ones. Thus, the proposed solution is a preliminary step in the uncertainty removal task.
Application of plasma technologies for increasing catalysts activity in the chemical industry
Authors: Pavlov Vladimir B.
Published: December 2022

The article discusses the results of processing some catalysts used in the chemical industry using plasma technologies. The catalysts already used in production were treated in vacuum with a beam of argon ions with the addition of oxygen. The experiments were carried out with different values of the ion beam current and the energy of its ions. As a result of the experiments, it turned out that the characteristics of plasma-treated catalysts already used turned out to be close to those of fresh catalysts.
Influence of water filtration rate on the functionality of the mining tailings dam
Authors: Kalashnik N A
Published: December 2022

By the example of one of the mining tailings dams on the Kola Peninsula the functionality of its guarding dam was investigated. For this purpose, a hydrogeomechanical 3D model was created, reflecting geometrical dimensions, geomechanical and hydraulic conditions of the dam operation. Using Plaxis 3D, calculations were made for 16 variants of increase of the coefficient of transverse filtration of water through the dam body. The dependences of soil displacements and volumes of filtered water on the degree of decrease of filtration stability of the dam were determined. The obtained results make it possible to determine graphically or arithmetically the predicted values of displacements and volumes of filtered water on the basis of the filtration coefficient measured in full-scale conditions. The applied methodical approach provides a scientific and technical basis for predicting the mechanical and filtration stability of the mine tailings dam for its specific geomechanical and hydraulic conditions.
Transformation of hydrostatic state in watercourse formation and scouring of tailings dam
Authors: Kalashnik A I
Published: December 2022

Model studies of the conditions of transition of the hydrogeomechanical state of the tailings dam into the filtration instability of the enclosing dam have been carried out in this work. Modelling of deformation and filtration processes in the hydrogeomechanical 3D model, built on the example of one of the mining enterprises of the Kola Peninsula, was applied. Model peculiarities of reconsolidation of the tailings pond soil, the guarding dam and the underlying geological basis were revealed. The values of stability coefficient of the guarding dam at given rates of water filtration through its body are determined. The model laws of transformation of the hydrogeomechanical state of the tailings dam of the mining enterprise are established. The obtained results provide scientific and technical basis for providing industrial and ecological safety of tailings dams, both of operating mining enterprises and mothballed facilities for storing of reclamated mining wastes.
The use of heat pipes in drying plants in the processing of fruits and vegetables
Authors: Kholikov Alijon , Khikmatov Doniyor
Published: December 2022

The article describes the use of heat pipes in drying plants in the processing of fruits and vegetables, selected coolant and material for heat pipes that are used in the drying process. A method is proposed for creating a vacuum for heat pipes, which will reduce the boiling point of the coolant inside the heat pipes. With experimental data, a laboratory experimental drying plant was developed and the temperature characteristics of the installation were determined.
Basic calculations of the movement of gas-liquid flows in dust collectors
Authors: Barakaev N R , Jalilov R S
Published: December 2022

Based on mathematical calculations of the movement of gas-liquid flows in the channels of a dust collector with an arbitrary generator, the equation of the lateral surface was found, which allows increasing the dust extraction coefficient.
Impacts of first- and second-order optimization in deep learning of turbulent fluctuations from gas puff imaging
Authors: Mathews Abhilash
Published: December 2022

Following the results of [1], which demonstrates a novel method to translate 2-dimensional measurements of HeI line radiation on turbulent scale into local plasma fluctuations via an integrated deep learning framework, this manuscript investigates the results when applying two separate techniques for optimization: Adam and L-BFGS. Fundamentally, the two approaches apply the same set of constraints and loss functions that combine neutral transport physics and collisional radiative theory for the 33D − 23P (587.6 nm line) transition in atomic helium whilst training the networks. The impact of these first- and second-order optimization techniques are investigated to examine their influence on numerical convergence and stability when seeking to analyze turbulent dynamics via gas puff imaging in experimental plasmas.
Non-linear free boundary simulations of the plasma response to resonant magnetic perturbations in ASDEX Upgrade plasmas
Authors: Mitterauer V , Hoelzl M , Willensdorfer M , Dunne M , Schwarz N , Artola J , Team JOREK , Team ASDEX Upgrade
Published: December 2022

A promising method for the control of Edge Localized Modes (ELMs) in H-Mode tokamak plasmas is the application of Resonant Magnetic Perturbations (RMPs), where small helical field perturbations are introduced into the plasma via a set of external coils. While RMPs are used for suppression of ELMs in many present-day tokamaks, the mechanisms that lead to RMP-ELM control are still subject of debate.

Here, we use the non-linear MHD code JOREK to investigate the penetration of the magnetic perturbation fields into ASDEX Upgrade (AUG) plasmas. We present an extension of the coupled JOREK-STARWALL code, that replaces the commonly used fixed boundary treatment with a free boundary treatment. Instead of prescribing the magnetic field at the boundary according to the vacuum field using Dirichlet boundary conditions, natural boundary conditions are applied, so that the magnetic field and plasma current density are evolving freely at the boundary. This allows a fully self-consistent development of the plasma response and the magnetic perturbation in the whole computational domain. The direct comparison of both approaches demonstrates that the artificial suppression of the plasma response with the fixed boundary treatment reduces the excitation of marginally stable modes. An overall larger perturbation is observed using the free boundary approach.

The presented simulations are performed in realistic geometry with fully realistic plasma parameters and plasma flows based on reconstructions of experimental AUG equilibria. While the use of realistic plasma parameters makes the simulations particularly challenging, it also allows for quantitative comparisons to the experiment. When the RMP induced corrugation of the boundary is compared to electron density measurements from the lithium beam emission spectroscopy, only the free boundary approach shows excellent agreement with the experiment.
Account of non-standard orbits in computations of neoclassical toroidal viscous torque in the resonant plateau regime of a tokamak
Authors: Buchholz R , Kasilov S V , Kernbichler W , Grabenwarter L , Savchenko A A , Albert C G
Published: December 2022

This article extends theoretical details based on a short paper originally submitted to the 2022 EPS conference in plasma physics [1]. The quasilinear theory of resonant transport regimes in a tokamak is developed for the general case of orbits forming various classes separated in phase space by homoclinic orbits with infinite bounce time. Beyond standard orbits (banana and passing orbits) also all types of non-standard orbits (e.g. “potato” orbits) are taken into account. In case of a weak radial electric field, such orbits are usually present only near the magnetic axis. If the radial electric field cannot be treated as weak, there can be arbitrary many classes, located elsewhere. The present approach covers all such cases and is demonstrated on a specific example of a radial electric field profile. The resulting quasilinear kinetic equation is applicable to compute neoclassical toroidal viscous (NTV) torque in a tokamak with non-axisymmetric magnetic field perturbations. A fully non-local approach to NTV computation has been realized in the upgraded version of the code NEO-RT. Based on a generalization of magnetic flux surfaces to drift surfaces, the notion of a local thermodynamic equilibrium is extended for our purpose. We obtain an expression for the integral toroidal torque within a chosen flux surface and dicuss means to compute such integrals taking singularities in bounce and precession frequencies into account.
Linear stability of the JET H-mode pedestal
Authors: Hamed M. , Pueschel M.J. , Citrin J. , Muraglia M. , Garbet X. , Camenen Y.
Published: December 2022

The stability of microtearing (MT) in the JET H-mode pedestal is investigated by means of both linear gyrokinetic simulations using the GENE code and a theoretical calculation. In order to determined the role played by MT in tokamak pedestal and to evaluate the role played by physical parameters, on MT destabilization a reduced linear model has been presented and compared with gyrokinetic simulations. The analytical model allows a good prediction of the impact of the different physical parameters, like the collisionality in the pedestal.
Iterative approach to linear ideal MHD modeling of plasma response to 3D magnetic perturbations in tokamaks
Authors: Lainer P , Kasilov S V , Kernbichler W , Reichelt M , Albert C G
Published: December 2022

The class of plasma instabilities known as edge-localized modes (ELMs) is of special concern in tokamaks operating in high-confinement mode, such as ASDEX Upgrade and ITER. One strategy for ELM mitigation is the application of resonant magnetic perturbations (RMPs) via external coils. Kinetic modeling accurately describes the plasma response to these RMPs ab initio, particularly the parallel shielding currents at resonant surfaces. Away from resonant surfaces, ideal magnetohydrodynamics (iMHD) is expected to yield sufficiently accurate results, providing a computationally less expensive option that could complement kinetic modeling.

The code MEPHIT has been developed to solve the linearized iMHD equations in a way that is compatible with iterative kinetic modeling approaches. We consider an axisymmetric iMHD equilibrium in realistic tokamak geometry under the influence of a quasi-static non-axisymmetric external perturbation from ELM mitigation coils. The plasma responds to this external magnetic perturbation with a current perturbation, which in turn produces a magnetic field perturbation. The resulting fixed-point equation can be solved in a self-consistent manner by preconditioned iterations in which Ampère’s equation and the magnetic differential equations for pressure and current are solved in alternation until convergence is reached. After expansion in toroidal Fourier harmonics, these equations are solved on a triangular mesh in the poloidal plane using finite elements. These results are then benchmarked against established codes.