bluuebunny/crossref_metadata_2025 huggingface dataset:
A Simple Proof of Bieberbach Conjecture
Authors: Yao Wenqing
Published: December 2022

The famous Riemann mapping theorem, which was established in 1851, states that every proper subdomain of the complex plane that is simply connected (without “holes”) is the image of the unit disk under a univalent analytic mapping f(z). This is the most significant characteristic of univalent analytic functions. The domain D, the image point f(0) in D, and the restriction that f’(0) be a positive real integer each independently define the mapping function f(z). One naturally asks how geometric aspects of the image domain f(D) represent analytic properties of f when considering univalent analytic functions as “Riemann mappings”. This is the perspective of geometric function theory, whose primary issue was solved by de Branges’ proof. The Bieberbach conjecture (hereinafter referred to as “BC”) is essentially a claim on the extreme nature of the Koebe function. Therefore, a key subject in this article is to make an explanation of the Koebe function and intepret why it is the best contender to be “largest” in the sense of the conjecture. Also, a detailed but easy understanding noval proof is given for this conjecture.
Analysis on Infection Wave and Decay of Transmission Risk Based on Spatial SIR Model - Taking COVID Epidemic as an Example
Authors: Wang Yunda
Published: December 2022

Starting with the spatial SIR model, this paper gives the strict boundary conditions, and obtains two theorems in the process of infectious disease transmission through theoretical analysis. After that, the partial differential equations are transformed into ordinary differential equations by the method of traveling wave solution, and the solutions of infectious wave velocity and hypergeometric function are further derived. Beside local diffusion operator model, the paper also developed global transmission risk functions as convolution kernels and discovered their properties. The solution of the spatial infectious disease model is visualized by programming, and the influence of parameter changes on the solution is discussed. Finally, some variants of the model in special cases are given. This paper proves that under generalized assumption the three population densities of the spatial SIR model results at the origin cannot take extreme values at the same time, and when the infected density takes extreme values at the origin, the higher-order derivative of the infected density to the space is zero. The hypergeometric function method verifies the solution at infinity of the equations, and the above solution can be used to approximate when the distance from the infection source radius is large. In this paper, the discussion on the impact of the changes of several infectious disease parameters can inspire the methods of epidemic prevention and control.
Feature Selection Based on Stock Prediction Model
Authors: Li Deyang
Published: December 2022

Stocks as an important part of financial investment are becoming more and more popular, and they have higher rates of both returns and risks. Making a prediction for the stock can reduce its risk and help people gain returns. So far, the traditional machine learning model is still unable to achieve ideal accuracy. The paper is devoted to analyzing the input features to improve the performance of stock forecasting models. Aiming at the problem that the traditional stock prediction algorithms produce different accuracy for the models constructed by different input features, the paper, through a method of establishing a long-term memory (LSTM) model, predicts the stock. The Shixia Technology Stock’s history data includes 5 features as the dataset and chooses the different feature as the input. In the experiment in this paper, different results are produced by subtracting one different input feature at a time. Finally, the model’s predictions were compared with each other by the R_square and RMSE, and the analysis revealed which feature could have a greater impact on the stock prediction. The paper finds that the different input features have different influences on the model fitting effect and the prediction accuracy on stock forecasting based on the same neural network model.
Optimal Values Selection of Q-learning Parameters in Stochastic Mazes
Authors: Zhou Xiaolin
Published: December 2022

The model-free characteristic of the Q-learning algorithm, without obtaining information about the environment and being available for agents to learn by themselves, enables Q-learning to be widely applied to path planning fields. Nonetheless, the selection of parameter values will have a crucial impact on the results. In this paper, how to determine an appropriate value of learning rate and discount factor and these parameters’ effect on the overall results will be presented. The agents with different learning rate or discount factor values will perform in randomly generated mazes, the results of which will be aggregated and compared. When the learning rate equals 0.9, under the condition of setting the learning rate as variable and discount factor as invariant, the aggregated data of 0.9 can reach convergence way more quickly than in other settings (0.6, 0.3, 0.1); when the discount factor equals 0.9 and the experiment follows the unique variable principle, the aggregated data of 0.9 searches for shorter path length and faster than other groups (0.6, 0.3, 0.1); when both the learning rate and discount factor are set to 0.9 – other groups are 1.0, 0.1, and 0 – the group of 0.9 is more stable than the group of 0.1 and shows convergence, which does not appear in the group of 1.0 and 0, within 80 iterations.
Variant Modern Solutions to Central Processing Units’ Overheating Problem and Evaluations on Applications
Authors: Zhang Xuan
Published: December 2022

As the society is technologically advancing, there is an increasing demand for advancements in computers. Therefore, computers will be replacing more human jobs in the future which force computers to work more frequently. This foreshadows that computers may encounter more problems such as overheating problem in the future as they are operating. Overheating problem is indeed a problem to be researched because it may cause serious damages to the computer overall, such as shortening its lifespan or reducing its memory. In this article, we aim to demonstrate different existing modern solutions that may prevent Central Processing Units in computers from overheating. Furthermore, this article will be evaluating on the solutions that are presented.
Active Noise Cancellation and Its Applications
Authors: Song Yu
Published: December 2022

The goal of this review is to introduce the concept of Active Noise Cancellation (ANC) technique and explain the core algorithms supporting this technology. Through showing the implementations and major features of those algorithms, we were able to gain a better understanding of what’re the dominating algorithms used by the ANC technology and both the traditional and non-traditional applications of ANC in today’s market. Finally, the review also reveals the potential problem with the ANC technique and the opportunities for improvements.
Optoelectronic Techniques Boost the Investigation on Hysteresis and Ion Migration in Perovskite Photovoltaics
Authors: Chen Ke Liang
Published: December 2022

Perovskite solar cells (PSCs) have drawn much attention in the photovoltaic field. At present, the energy conversion efficiency has achieved 25.5%. However, the hysteresis effect in the characterization of PSCs seriously affects the accuracy of PSCs technology. Therefore, hysteresis effect has become the object of attention in order to improve PSCs. In this paper, various photoelectric characterization techniques are mentioned for the study of hysteresis phenomena. Photoelectric characterization methods, space charge limited current, electrochemical impedance spectroscopy, transient photocurrent/photovoltage are introduced. In the end, hysteresis is a shift in the representation of carrier dynamics due to ion migration. Hysteresis shows a characteristic of sweep speed dependence, indicating that ion migration is a slow and low frequency behavior. By increasing the bias voltage, ion migration can be more intense and the hysteresis will be more obvious.
Impacts of Laser Power and Scan Speed on Temperature Field and Molten Pool of ZL104 Aluminum Alloy Selective Laser Melting
Authors: Shi Yuxuan
Published: December 2022

Selective laser melting (SLM), a significant branch of laser additive manufacturing (LAM) technology, has become a popular topic of research in engineering, materials and many other disciplines. SLM can transform metallic powders directly into 3D components, which allows SLM to offer the unique flexibility of manufacturing parts with complex structures. The quality of the product is closely related to the characteristics of the temperature field, as well as that of the molten pool. Because of the high localized temperatures and the rapid cycles of melting and solidification during SLM, it’s difficult to monitor the temperature field in real time. Hence, numerical simulation is often used to study the SLM process. In this work, the SLM process of ZL104 aluminum alloy was simulated using the CFD method, and the influences of processing parameters, including laser power and scan speed, on the temperature field and the characteristics of the molten pool have been investigated. Results showed that when the laser power increased, the peak temperature of the molten pool also mounted, however, the maximum temperature of the molten pool fell as the scan speed rose. The dimensions of heat affected zone (HAZ), including the width and depth, increased with growing laser power, but decreased with the increase of scan speed.
Daylighting Performance of Sunlight Transmission and Concentration via Plastic Optical Fibers
Authors: Chen Zeyao
Published: December 2022

The energy-saving technology of this thing is thriving. One of promising technology is the daylighting system via optical plastic fibers. It has many advantages, and its characteristics need further research. This paper analyses the transmission characteristics, attenuation rate, and incident angle of the optical fiber. The test data shows that the spectrum, color rendering index are good, and the energy efficiency is high. This shows that plastic optical fibres have excellent development prospects for daylighting.
A Sensor Array-based Control System Design for the Interior Environment of Driverless Cars
Authors: Li Xinran
Published: December 2022

Highly intelligent driverless cars require intelligent, user-friendly and high-safety interior environment control systems to match. In this paper, through the use of vision sensors, sound sensors and a variety of environmental sensors to form a sensor array, and through the embedded microprocessor for centralized control, the design completed with face recognition door opening, cry detection window opening, vibration detection alarm, haze detection defrost, automatic thermostat control, automatic light brightness control, internal environment remote monitoring and other functions in one of the driverless car intelligent internal environment control system. The test results show that the system designed in this paper is a good solution to the problem. The test results show that the system designed in this paper is functionally rich and scalable, highly intelligent and suitable for the needs of the general public, and helps to improve the ride comfort and safety of driverless cars.
The Application of Computer Aided Optimization Design
Authors: Bao Longfei
Published: December 2022

The Computer Aided Optimization Design (CAOD) is one of the most significant piece of software in the world especially for companies involved in manufacturing and designing. The software can be used for different objectives when paired with other software in the company. This paper mainly introduces the application and benefits of CAOD in five different fields. First, the CAOD is critical for design engineers involved in designing automotive and airplane body shapes to achieve various objectives such as high capacity, fuel efficiency, and high performance. Second, it can be applied to turbines for wind mills to ensure they are long enough and can operate optimally even at slow wind speeds. Third, it can benefit the manufacturing process to redesign the factory floor and setting up machines in various sections on the factory floor. Moreover, CAOD has also diversified into other areas such as healthcare where it is used in robotic surgery system and repair of intense fractures and damages. Last but not least, the greatest application of CAOD may lie in the computer animation industry.
Design and Optimization of Automotive Air Conditioning Duct Based on CFD Algorithm
Authors: He Jiahao
Published: December 2022

Nowadays, the air conditioner (AC), as an important guarantee for driving comfort and endurance, has attracted more and more attention. The pipe connecting the air conditioner refrigerator and the air outlet of the cockpit instrument panel is known as the air duct. Its structural characteristics and fluid flow characteristics are related to the refrigeration efficiency of the whole air conditioning system. The air supply performance of the air duct directly affects the uniformity of the temperature field and speed field in the car, thus affecting the comfort performance of the car [2]. Limited by the layout space, the design of air conditioning duct is the most difficult part of the design of automobile air conditioning system [1]. Therefore, how to optimize the air duct of automotive air-conditioning to meet the size design of the car while being more energy-efficient is an important research direction. This paper focuses on the simulation design and further optimization of the model of the air duct of automotive air conditioning through CFD algorithm. The author uses the Soildworks software for preliminary modeling, meshes the established model with Meshing, and applies the Fluent software to simulate the fluid flow characteristics in the pipe. By inputting a given flow to the inlets, the air volume of each outlet can be simulated. Based on the initial air-conditioning duct model of a vehicle model, the pipe turbulence problem and the uneven distribution of air volume at each outlet in the simulation process are improved under the condition of ensuring the existing size, and finally the rationality of the improvement is verified.
Research on transformer condition evaluation based on oil chromatography differentiation threshold
Authors: Yang Pei , Qiao Junfeng , Wang Gang
Published: December 2022

As one of the important power transmission and transformation equipment, the reliability of transformer is directly related to the safe operation of power system. At present, the on-line monitoring technology based on dissolved gas analysis in oil is widely valued by researchers all over the world because it can continuously monitor the operation status of transformers and timely and effectively find the early faults of transformers. In this paper, the on-site oil chromatography data are differentiated and classified according to the voltage level of the transformer. The curve fitting method is used for statistical analysis and to build a distribution model. The cumulative probability is associated with the defect rate and failure rate of the equipment, and the corresponding threshold value is obtained by using the inverse cumulative distribution function as the attention value and warning value. By using this method, the attention values of the volume fraction of dissolved gas in oil and the gas production rate of dissolved gas in the existing national standards are improved, and the corresponding warning values are calculated to make the warning mechanism more flexible and reliable.
Partial discharge location method in GIS coaxial bus structure based on multi-normal photoelectric array
Authors: Li Chen , Ren Ming , Wang Yue , Guan Haobin , Xia Changjie , Yu Jiahe , Zhang Tao , Miao Jin
Published: December 2022

Partial discharge is an important reason for the failure of GIS equipment, and its detection can determine the type and position of the defect in GIS. In the discharge inspection, accurate positioning of defects can provide an important reference for maintenance. In response to this, this paper proposes a discharge optical location method based on multi-normal photoelectric array. Based on the SiPM sensor, a multi-normal array is designed and built into the coaxial structure of GIS equipment. Measuring the responses of each unit in the array to get the response ratio of each element and calculate the direction of the discharge light in space. This paper firstly introduces the array structure, and proposes a solution algorithm in space, which uses the proportional relationship of multi-normal elements to solve the discharge direction. Secondly, the feasibility and error source of this method are verified in the simulation software. Finally, the application effect of this method in actual power equipment is verified by actual measurement, and the results show that this method can accurately locate the partial discharge in GIS.
Prediction of Ultra-Short-Term power system based on LSTM-Random forest combination model
Authors: Fang Ziqiang , Yang Ziteng , Peng Haiyang , Chen Guoqing
Published: December 2022

The ultra-short-term forecast of the power load system plays an important role in the operation of the power market and economic dispatch. An excellent ultra-short-term power load prediction model can not only greatly reduce the loss of power operation, but also make a reasonable power generation plan accordingly to reduce the waste of power. In this paper, a model applicable to forecasting the ultra-short-term power system is proposed by combining LSTM and Random Forest using the reciprocal error method, based on the power load data of the 10th Teddy Cup Data Mining Competition. The illustrating example shows that the mean absolute percentage error (MAPE) of the combined prediction model of LSTM-Random Forest is 1.40%, the error of the combined model is significantly lower than the uncombined model, implying that the prediction accuracy of the combined prediction model is significantly higher than that of the LSTM model and Random Forest model.
Preparation and electrochemical properties of vanadium-based anode materials for zinc ion battery
Authors: Ren Jiaxin , Yang Chun , Zhou Beibei
Published: December 2022

Although water zinc ion battery (ZIBs) has certain advantages in production and application period, but the speed performance and service time is not strong, always hinders the reusability and rapid charging technology. In order to solve this problem, researchers proposed to improve the reaction kinetics on the basis of stable electrode structure. So this article research using solvent and adding thiourea to design a hybrid structure, the structure is made from manganese doped V6O13 nanobelts and navier-stokes modified porous carbon structure, consisting of one dimensional porous nanometer structure can form diffusion channels, and can provide relatively abundant energy storage sites, and zinc ions doped into V6O13 electronic structure can be further adjustment. In order to effectively control the huge volume expansion and optimize the electrical conductivity, n-S modified carbon structure with electrical conductivity can be used to protect the nanoribbons and effectively improve the electron transport rate in the electrochemical reaction. This electrode structure can not only accelerate the diffusion rate and reaction kinetics of zinc ions, but also show cyclic stability and high rate performance. This study mainly analyzed the application effect of reduced graphene oxide coated with sea urchin-like VO2 as anode material of water zinc ion battery, so as to provide effective basis for material preparation and electrochemical performance research.
Overview of the IV International Conference on Applied Physics, Information Technologies and Engineering – APITECH-IV 2022
Authors: Barakaev N R , Sharipov M Z , Abrorov A S , Rakhmonov Kh K
Published: December 2022

The overview describes the main directions and results of the IV International Conference APITECH-IV 2022 held in Bukhara, Uzbekistan on 6-9 October 2022. It gives the details about the participants and the proceedings. The purpose of the Conference is to share the experience of leading experts in the application of modern methods of applied physics and information technology in high-tech production, in the fields of aerospace, energy, chemical and oil and gas engineering.
Varizonicity and surface levels in ionic crystals
Authors: Karimov Z I , Mukimov K , Oksengendler B L , Suleymanov S X , Iskandarova F A
Published: December 2022

The problem of the formation of varizonicity in ionic crystals is investigated. It is shown that in this case the electronic structure of the surface states becomes special – a near-surface potential well appears, as a result of which the local states radically differ from the Tammov states. A similar effect, in principle, should take place in cases of varizonicity of covalent crystals, which is due to special alloying in them. A consideration is made about the special situation in HTS materials: a combination of external and internal varizonality.
Computer simulation of ice film sputtering from Au(111) surface
Authors: Kutliev Uchkun , Otabaeva Kamola , Karimov Mukhtorjon , Woiciechowski Igor
Published: December 2022

Mass spectrometry of secondary ions represents a combination of analytical methods, which allows you to study the molecular characteristics of the solid state. On the basis of this method, the use of charged charging frequencies is directed at the power, usually in the range of tens of thousands of electron volts. Based on the molecular dynamics method, we simulated sputtering process in the form of water molecules and clusters of water films covering Au(111) on the surface at normal incidence. It is shown that the obtained mass spectra of sputtered particles contain peaks related to several water molecules. The analysis of the obtained results showed that peaks were formed on the mass spectrum of sputtered particles, which belong to water molecules, water clusters, and Au atoms. The results played a huge role in studying the surface of thin films and molecular spectroscopy. The obtained calculation results showed that the number of incident particles directly affects the sputtering process, that is, the greater the number of incident particles, the more intense the process of sputtering of the atoms of the upper layers of the substrate. This is due to the fact that the incident ions, destroying the structure of the crystal, namely, violating the periodicity of the upper atomic layers, remain in the substrate of the crystal.
Modeling of nonequilibrium cross-diffusion systems
Authors: Mamatov A U , Nurumova A Yu
Published: December 2022

In this research, we investigate the modeling of cross-diffusion systems that are not in equilibrium. For a particular equation, it is shown that the parameter values exist and have a numerical solution. A source describes the system of equations considered in this study as being based on the majority of physical processes, such as the cross-diffusion process in this system, thermal conductivity, and polytrophic filtration of gas and liquid in nonlinear media. Numerous partial solutions exist for these equations. The development of an integral self-similar solution is one of the most important approaches to analyzing the problem at hand. Initial construction of a system of self-similar equations using a nonlinear subtraction technique. The front for the equation of nonlinear heat generation with doubled energy was estimated, the localization process was observed, new effects were observed, an algorithm was constructed based on the obtained self-similar solution, a program code was developed in the programming language, and the process modeling was visualized.
Mathematical modelling of motion control system in the MLC mode
Authors: Smirnov Mikhail N , Smirnova Maria A , Smirnov Nikolay V , Smirnova Tatiana E
Published: December 2022

Performing different manoeuvres in vertical and horizontal planes is one of the most important tasks that rise during the control of any object. In the paper the problem of implementing movement in the mode of moving along a linear coordinate (depth) for an unmanned underwater vehicle is considered. The algorithm for construction the control law that satisfy the specified conditions, e.g. the specified equilibrium position in vertical plane, astaticism, is presented. The control law with filter is constructed. This algorithm was implemented in MATLAB with the subsystem Simulink. MATLAB one of the most powerful systems for computer modelling and analysis of dynamic systems, so this algorithm and its realization with small changes can be easily used for any object.
A mathematical model of an inductively coupled radio-frequency discharge at low pressure as nonlinear partial eigenproblem
Authors: Yu Shemakhin A , Zheltukhin V S , Yu Shemakhin E , Samsonova E S , Terentev T N
Published: December 2022

A new approach for modeling steady state inductively coupled radio frequency discharges at low pressure is described. A simple one-dimensional model is considered, which includes Maxwell’s equations and the electron balance equation with boundary conditions of the third kind. It is shown that the system of boundary value problems is a two-parameter partial eigenvalue problem. The smallest eigenvalue of the problem is the boundary value of the magnetic field strength. The second parameter of the problem is the concentration of electrons at the center of the plasma bunch. The developed approach makes it possible to calculate the inductor current required to maintain a steady state of the discharge. The results of calculations of the dependence of the inductor current, electron density, electric and magnetic fields on pressure are presented.
Photoelectric properties of solar cells based on pCdTe-nCdS and pCdTe-nCdSe heterostructures
Authors: Otajonov S M , Ergashev R N , Axmedov T , Usmonov Ya , Karimov B
Published: December 2022

In this paper, we study the photoelectric properties of pCdTe-nCdS and pCdTe-nCdSe-based film heterostructures. It is shown that the high value of the electron diffusion length in pCdTe slick (pellicle) is due to the presence of a built-in field in it. The shift in the photosensitivity maximum is explained by changes in the band gap of cadmium telluride. As shown, the accumulation coefficient increases with raising thickness of the wide-gap layer. It has been established that the short-wavelength edge of the photosensitivity of the pCdTe-nCdS structure begins to increase sharply at a photon energy of hv ≤ 2,3 eV, while the photosensitivity of the pCdTe-nCdSe structure already at a photon energy has a significant value ∼ 100 μA/mV.
Technologies for the development of high-viscosity oil fields
Authors: Varisova Raushanya R
Published: December 2022

With the depletion of light oil reserves, the share of current reserves of viscous and high-viscosity oil will increase, therefore, the search for effective methods for the development of deposits of high-viscosity oil is a natural direction for the development of the oil industry. Currently, thermal methods of exposure are widely used in the development of deposits of high-viscosity oil. Despite the fairly good efficiency of this method, thermal exposure technologies are characterized by high energy intensity, which in some cases can significantly reduce the economic attractiveness of the method. This issue is particularly acute in the context of a decline in world oil prices.
The algorithm for the detection of information signals
Authors: Chernoyarov Oleg , Dachian Serguei , Glushkov Alexey , San Kaung Myat , Litvinenko Vladimir
Published: December 2022

The problem of detecting signals in the presence of interference arises in various areas of radio engineering and is solved by using the selected indicators of the signal presence that are compared with a specified threshold. In this paper, an algorithm for detecting a discrete signal is proposed, with the decision threshold that determines the false alarm probability and does not depend on the noise level, while the missing probability depends only on the signal-to-noise ratio. The decision is made according to the number of exceedings of the threshold level by the modulus of the logarithm of the ratio of the amplitudes of the received and previous symbols in a sampling of a given size. For the false alarm and missing probabilities, the theoretical expressions are obtained. Statistical simulation of the detector for the case of a phase shift keyed signal is carried out. It is proven that the number of false alarms is not influenced by the noise parameters while the introduced detector provides high noise immunity and efficiency.
Modeling of laser reflow of a powder heat-protective coating on a carbon composite
Authors: Alisin V V , Roshchin M N
Published: December 2022

The article discusses the issues of creating a heat-shielding coating to protect carbon composites from oxidation and ablation in high-temperature gas flows. The prospects of creating a framework structure containing a refractory zirconium dioxide powder in a metal matrix are substantiated. Particular attention is paid to the distribution of heat fluxes in the process of laser melting of the coating. The temperature in the coating is calculated as the melt front propagates, which opens up the possibility of optimizing the parameters of the coating laser processing technology. The developed technology is promising for the protection of carbon composites in the conditions of their use in the flow path of turbine engines.
OES diagnostics of NF3/Xe plasma for deep structures in LiNbO3
Authors: Osipov Artem A , Gagaeva Alina E , Speshilova Anastasiya B , Osipov Armenak A , Alexandrov Sergey E
Published: December 2022

In this work, in situ non-perturbing method of optical emission spectroscopy is used to examine the features of the emission spectra of NF3/Xe plasma, which can be used for the process of continuous plasma-chemical etching of lithium niobate. To understand the physicochemical processes occurring in plasma, the influence of high-frequency power, pressure in the chamber, bias voltage and substrate temperature on the emission intensities of the F, N, Xe lines was studied. It was determined that increasing the bias voltage from -300 to -50 V and the temperature from 50 to 300°C doesn’t change the relative intensities of the analysed spectral lines, while increasing the high-frequency power from 500 to 750W and decreasing the pressure from 1.95 to 0.95Pa increase the intensities of the F, N, Xe lines.
Study of a linter machine with steel gaskets in production
Authors: Mukhammadiev D M , Ibragimov F Kh , Abzoirov O Kh
Published: December 2022

The article presents the results of the study of a linter machine with steel gaskets in an industrial environment. An analysis of the structures of aluminum saw gaskets was conducted, and their main shortcomings were established. To eliminate the shortcomings of aluminum gaskets, technical solutions were proposed. For this purpose, a new design of saw gaskets with steel pads for cotton gins was proposed. Steel gaskets for linter machines were made. The dimensions of the saw cylinder with steel gaskets after assembly are determined. The main energy indices of the saw cylinder electric motor were determined. The current in the electric motor of the saw cylinder was 41.6 A. In addition, an increase in the productivity of the linter machine with steel gaskets by 50 kg/h was established due to the precise assembly of the saw cylinder. The results of studying a linter machine with steel gaskets in production showed the possibility of using a steel saw gasket when assembling the saw cylinders of a linter machine.
Intelligent technologies in the development of cyber-physical production systems
Authors: Vershinina L P
Published: December 2022

The tasks, the solution of which plays the most significant role in the development of cyber-physical production systems, are identified. The influence of the features of the production of high-tech products on the choice of ways to solve these problems is shown. An approach to solving problems of monitoring, measurement, modeling and technological process control based on one of the directions of artificial intelligence - the theory of fuzzy sets and fuzzy logic is considered. Intelligent technologies for measuring and modeling technological process parameters are described. The model allows to predict the quality of the manufactured product based on the current state of the process, to solve questions about the expediency of adjusting operations, to choose adequate management. As a result, the efficiency of the cyber-physical production system is provided in changing conditions.
Application of radiophotonics methods and devices in multifrequency microwave remote sensing radiometric systems
Authors: Rostokin I N , Fedoseeva E V , Rostokina E A , Shchukin G G
Published: December 2022

The article considers the possibility of using methods and devices of radio-photonics in the composition of microwave radiometric systems for remote sensing of the atmosphere in order to significantly improve the basic tactical and technical characteristics of microwave radio-measuring equipment. The analysis of possible options for the use of radio photonics devices as part of multi-frequency microwave radiometric systems is carried out. The results of the structural study of a promising microwave radiometric system for remote sensing of the atmosphere are presented.
Analysis of heat and mass transfer process while cooling particle boards produced on low-toxic resins
Authors: Ischenko T L , Efimova T V
Published: December 2022

Particle board production technology is a complex process including a number of important operations, and the quality indicators of the finished product largely depend on it. One of such operations is cooling of hot plates after pressing. Increasingly, low-toxic resins are used in particle board production. However, the modes of post-press exposure of particle board on resins with low formaldehyde content should differ from the well-known ones. Therefore, the purpose of this work was to develop a mathematical model (a system of equations), that will theoretically calculate the duration of plate cooling, as well as display the temperature on its surface and over the cross section for any time interval. As a result of the work carried out, a mathematical model has been proposed that enables theoretical calculation of cooling duration of particle board produced on low-toxic resins and to display the temperature on its surface and over the cross section at any time interval.
Vacuum-arc technology and equipment for cleaning and surface treatment of metal products operating under load
Authors: Moldahmetova A E , Vasil’ev I M , Kochetkov A N , Sabitov L S , Zagidullin R R , Kiyamov I K
Published: December 2022

The material of the product should be considered as an integral concept that combines the substance, the technology of its production, design, technology of its manufacture and processing. The durability of products depends not only on the properties of the material, determined by the manufacturing technology and volumetric hardening, but also to a large extent on the properties of the surface. Its role in ensuring the performance properties of products is constantly increasing, which, along with the widespread use of traditional methods of chemical-thermal treatment, has contributed to the emergence and development of a new direction - surface engineering by methods of energy and physico-chemical effects. The high rate of high-frequency heating (hundreds of degrees per second) causes a shift in phase transformations to higher temperatures. Therefore, the high-frequency quenching temperature should be higher than the quenching temperature of ordinary furnace heating, and the higher the higher the heating rate. The current density across the section of the part is uneven, on the surface it is much higher than in the core. The main amount of heat is released in a thin surface layer. The depth of current penetration into the metal depends on the properties of the heated metal and is inversely proportional to the square root of the current frequency. The higher the current frequency, the thinner the resulting hardened layer. A reliable method of hardening the surface layer can give comparable results only if the quality of the surface is stable, including its cleaning. The surface condition of the part (tool) depends not only on the structure of the base material and all the conditions for its manufacture, but especially on the last operation of its production or processing. Research is being conducted, among other things, within the framework of the AP14869891 project “Increasing the operational life of heavy-loaded railway transport parts using innovative plasma technology”.
The problem of electromagnetic wave transmission in a circular waveguide
Authors: Alexandrova I L , Osipov E A
Published: December 2022

The article deals with the problem of transmission in a circular waveguide, in the cross section of which there is a thin metal screen. The waveguide is bounded by a perfectly conducting surface. The transmission problem is an auxiliary problem that arose when solving inverse diffraction problems. In the transmission problem, it is required to find the electromagnetic field in the waveguide on one side of the screen by a given field on the other side of the screen: both by given waves incident on the screen and by given waves leaving the screen to infinity. It is shown how the transmission problem can be reduced to an infinite system of linear algebraic equations. To solve the resulting system, it is proposed to use the truncation method. We study under what conditions the numerical solution of the transmission problem will be stable to small perturbations of the input data.
Measurement technique for increasing the allowable dimensions of antennas tested in a collimator installation
Authors: Choni Yu I , Abuhadma L K T
Published: December 2022

Large collimator setups are often in use for antenna radiation pattern measurements. Their quiet zone size limiting the allowable dimensions of the antenna under test, as a rule, do not exceed a half of the collimator’s profile. Retrieving ARP from measurements in a non-ideal environment can be a means to expand the working area. The subject of the article is such a technique based on of the representation of a real field by a converging cluster of plane waves. It turned out that at the stage of studying the field of the collimator, despite the requirements of the uniqueness theorem, measurements may be carry out on a certain limited area of the boundary surface. Acceptable results are obtained when the working area is up to 90% of the collimator cross section.
Effect of temperature on the current-voltage characteristics of PdFe/Cu and NiCo/Cu bimetallic catalysts in alkaline alcohol electrolytes
Authors: Tarantseva Klara , Korosteleva Anna , Tarantsev Konstantin , Krasnaya Elena
Published: December 2022

The temperature rise effect on the electrochemical activity of catalysts on a copper substrate in alkaline alcohol solutions has been studied. The object of research was bimetallic PdFe/Cu and NiCo/Cu catalysts obtained by galvanic deposition on a copper substrate. The studies were carried out in immiscible liquids EtOH + K2HPO4 + H2O. The upper phase in this system of liquids is aqueous solutions of ethanol (“alcohol layer”), the lower phase is aqueous solutions of dipotassium phosphate K2HPO4 (“salt layer”). It was found that elevate temperature from 20°C to 60°C improve the activity of all catalysts. It was found that the Ni80Co20/Cu catalyst is highly active in the oxidation and reduction of oxygen. The peak of the oxidation current increases 4 times with elevate the temperature up to 40 C, and 14 times with elevate temperature up to 60 C, compared with currents at a temperature of 20 C. The Pd90Fe10/Cu catalyst is active in relation to the oxidation of ethanol. Elevate the electrolyte temperature from 20°C to 40°C increase in the oxidation current by a factor of 1.4, and from 20°C to 60°C by a factor of 3.3. The maximum cathode current at the peak of recovery exceeds the maximum anode current at the peak of oxidation at 40°C by 1.83 times, and at 60°C by 1.15. This indicates a good regeneration of the electrode surface and the absence of oxide films and ethanol oxidation products on its surface. It was concluded that, despite the ambiguous effect of temperature on the processes occurring in the system, the improvement in the characteristics of the studied catalysts can be explained by the improvement in the processes of ethanol oxidation and improved mass transfer of the reagents.
Outflow of a supersonic gas jet into a liquid
Authors: Yakovchuk M S , Volkov K N , Emelyanov V N
Published: December 2022

Numerical modeling of the underwater outflow of a supersonic gas jet in a three-dimensional non-stationary formulation is carried out using an eddy-resolving approach based on a combination of RANS-LES turbulence modeling methods. The calculation of the interaction of a gaseous medium with a liquid is carried out using the VOF multi-phase model, the forces of surface tension and the compressibility of the liquid are taken into account. As a result of calculations, an unsteady pattern of the formation of a supersonic jet and a gas cavity in a liquid is obtained, the shock-wave structure of the flow is visualized, and pressure fluctuations in the liquid are estimated. The results of calculations are compared with the data of experimental high-speed photography.
Experimental research of the low-temperature drying process of tomato
Authors: Rasulov Shukhrat , Djuraev Khayrullo , Abidov Kamildjan , Usmanov Akhtam , Fayziev Amirulla
Published: December 2022

The scientific research presents the results of studies aimed at studying the patterns of tomato drying, the change in moisture released per unit time over the entire surface of the raw material and the change in temperature in the product layers, as well as the dependence of the mass of the product per unit surface on the drying speed. Wavelength ranges with a high level of liquid absorption during tomato drying were experimentally determined. It has been established that the acceleration of the movement of liquid drops in a capillary-porous structure in the direction from the inner layer to the surface is carried out by creating the appropriate temperature and pressure in the inner layer of the product. The isotherms of desorption and sorption of tomato raw materials during the drying process are given.
Study of heating kinetics and temperature fields of melon fruits under IR irradiation
Authors: Khaitov R.A.
Published: December 2022

This article is devoted to the study of heating kinetics, temperature fields, as well as determining the laws of non-stationary heat transfer processes during treatment of melon fruits with IR rays. These studies, in turn, make it possible to determine the heating time to the desired temperature under different radiation conditions, which is a necessary condition for achieving a positive effect of heat treatment in infrared radiation. At the same time, the study of temperature fields and heating kinetics is carried out in order to reach the optimal regime obtained in the treatment of melon fruits with IR rays as a result of planning the experiment. The optimization of the process shows that the most appropriate mode of heat treatment of melon fruits during drying is IR irradiation at an incident flux density of 23-24 kW/m2 in a pulsed mode: τ=95 (-40)+60 (-30)+60 sec. The analysis of heating kinetics and temperature field confirms the correct selection of the optimal modes obtained in controlling the process of treatment of melon fruits with IR rays and allows to establish the laws of heat-mass transfer.
Using the Monte Carlo method to determine the volume of excavation work
Authors: Tsvetkov V Ya , Oznamets V V
Published: December 2022

The article describes a method for calculating the volume of spatial models when performing earthworks. It is based on the Monte Carlo method. The solution of the problem is based on the use of photogrammetric survey and the construction on this basis of a digital model of the surface and a three-dimensional digital model of the result of excavation work. Additionally, a reference three-dimensional object is introduced, covering the volume of excavation work. The dimensions and volume of the reference object are known. A random number sensor with a uniform distribution is used. The method is based on comparing relations of discrete sets and continuous sets. The concept of discrete volume is introduced. Based on comparative estimates of discrete volumes and continuous volumes, the volume of a three-dimensional object is calculated using the known volume of the standard. The method excludes geometric volume calculations for complex configurations of walls and the bottom of a three-dimensional object. The article contains an assessment of the applicability of the method and an estimate of calculation errors.
Study of the efficiency of gas purification systems for metallurgical productions
Authors: Zolkin A L , Kolesnikov A S , Bityutskiy A S , Saradzheva O V , Stepina I V
Published: December 2022

One of the main tools used to study the technological processes of waste gases purification from metallurgical production is physical simulation. The problems of large-scale transitions that arise in the course of such a study can be circumvented by conducting experiments on industrial and (or) semi-industrial units. The article presents possible options for reduction of emissions of chlorine-containing components, taking into account the chemistry of the reactions occurring throughout the entire operational cycle of neutralization.
Determination of wear of the rotary-disk mixer according to the emulsion analysis data
Authors: Laponov S V , Erushonkov A N
Published: December 2022

There is in the presented paper shown a classification of rotary-disc mixers by various constructive and technological features. Also it is shown that mixers with fixed additional elements on discs are mostly widespread. A wear of additional work elements leads to decrease of efficiency of mixing and quality of the final product. The use of the photometric method of analysis of an emulsion allows to determine main parameters of the emulsion quickly and with sufficient accuracy. Having compared get results with the base results we can determine a degree of wear of working elements of the device.
Semiclassical theory of electronic states in multilayer semiconductors. Part 2
Authors: Rasulov V R , Rasulov R Ya , Mamatova M A , Qosimov F
Published: December 2022

The electronic states in multilayer semiconductors are studied theoretically in the semiclassical approximation. In this case, the Schrödenger equation is solved, where the potential is expanded into a series along the coordinate and is limited by the first four terms. It is shown that, in this case, the energy spectrum takes on discrete values, and the bending of the energy spectrum increases as the size quantization order increases.
Application of polycrotonaldehyde, obtained from recycling the waste “yellow oil”, in production of lubricants
Authors: Tilloev L , Dustov Kh , Turakhujaev S
Published: December 2022

The impact of polycrotonaldehyde, extracted from the waste “Yellow oil” produced during the alkaline treatment of pyrogas at Shortan gas chemical complex, on its properties lubricants as a dispersed medium and a dispersed phase after it is added to them have been studied in this paper. It has been established that polycrotonaldehyde can be used as a dispersed phase in the production of lubricants. Based on the research results, it has been proven that the addition of 2.5% to 7.5% of polycrotonaldehyde in the production of lubricants gives a positive result. The lubricant prepared by adding 5% of polycrotonaldehyde as a dispersed phase had a penetration number of 271 and a dropping temperature of 119 °C.