bluuebunny/crossref_metadata_2025 huggingface dataset:
Research on the effect of alignment form of strip welding on strip breaking in tandem cold rolling
Authors: Wu Zedong , Wang Xiaochen , Yang Quan , Xu Dong , Zhao Jianwei
Published: December 2022

The tandem cold rolling process is continuous production, and it is desired to achieve a stable operation process, the incoming materials need to be welded in the length direction before cold rolling. Usually the head and tail of the incoming material have a thickness dimension positive deviation, and there are two alignments in the thickness direction of the front and rear strip, so that different weld zone profiles can be formed. In this research, we built an FEA (finite element analysis) model of strip rolling with weld zone and relevant simulation conditions are designed to reveal the effect of alignment on the rolling process of the strip with weld zone. The risk of strip breaking between two alignment forms of the weld zone during the rolling process is further discussed and compared. It provides a reference for the setting of the alignment method of the laser welding machine in welding the strip in order to reduce the probability of weld zone breaking during the cold rolling process.
Game Theory Survey: Voting Methods of Preferential Ballot
Authors: Wang Yujie
Published: December 2022

This paper is a survey focuses on seven basic Voting Methods for Preferential Ballots. The purpose is to give a pellucid illustration of these Methods in consideration of Game Theory, and understand their intrinsic and associative properties. In order to understand these Methods and their efficacy, multiple techniques, such as Mathematical Modeling and Computer Programming, are used for evaluation and comparison. The ultimate goal is to find a Voting Methods which elect the most democratic winner.
Cauchy Integral Theorem and its Applications
Authors: Du Jun , Lu Sicen , Yang Tianyi
Published: December 2022

Italian mathematicians Girolamo Cardano and Raphael Bombelli made the initial dis covery of complex numbers somewhere in the 16th century while attempting to solve a algebra icquestion. The relevance of complex analysis in mathematics, physics, and engineering is incre asing now after hundreds of years of growth, particularly in the areas of algebraic geometry, flu id dynamics, quantum mechanics, and other relatedtopics. This paper discusses three aspects of integration of complex functions, properties and valuation of complex line integral, and Cauchy’s Theorem and its applications. It mainly gives a detailed definition of complex integrals, clarifies the properties of operations such as indefinite integrals and integral paths, and briefly lists several applications of Cauchy’s theorem and proves them. Several theorems are proved from Cauchy’s theorem, Local existence of primitives and Cauchy’s theorem in a disc, and Cauchy’s integral formulas.
A Genelization of Subgroups
Authors: Li Ruichi
Published: December 2022

Group theory is an important branch of mathematics. It has important applications in many disciplines, such as in physics, chemistry and quantum mechanics. The aim of this document is to provide readers with a greater understanding of the basic knowledge of group theory. Specifically, firstly, the concepts and properties of different types of groups, subgroups and the definition of coset are introduced, which will be used in the next section. Besides, several examples including groups, finite groups, infinite groups, subgroups and abelian groups are listed. Then, a discussion of the two simple theorems and some lemmas will be showed so that readers can be familiar with the properties of groups. This discussion will deepen the understanding of maximal subgroups. This paper investigates the basic definitions and theorems of group theory. In the future, more researchers can pay attention to group theory and the application of group theory in more areas.
Modeling of a Planetary Relay Station in Improving Deep-Space Probe Telecommunication Performance
Authors: Liu Zhuoyuan
Published: December 2022

For a deep-space probe(DSP), such as the Voyager, over an extremely far distance to transmit data back to Earth more efficiently, a model that adds one planet-based repeater(PBR) in the transmission path is developed. Firstly, a general model of the direct transmission link of any DSP is analyzed. Secondly, a general model of the relayed link is evaluated, with special cases considered. Then the simulation is conducted based on available technologies and statistics, and the results of the performance optimize the model and validate that the relayed link is effective. The conclusion is reached that, under certain constraints, a PBR located on Mars could provide the highest performance advantage over the direct link.
Review of ANC Algorithm
Authors: Diao Zhuo , Jin Conghao
Published: December 2022

In the contemporary society, the ANC (active noise cancellation) technology has become more and more popular. It has grown from its originally military and industry fields into commercial fields, and it is still being implemented into more and more areas and fields. In this paper, we briefly introduce some principal of ANC algorithms and contrast their results with the traditional ones and focus on challenges for future applications.
Research on Optimizing Transmission Efficiency and Illumination Distribution of Tubular Daylighting System
Authors: Huang Erdong
Published: December 2022

Although building lighting is paid more and more attention now, due to the limited areas illuminated by typical lighting, such as windows and skylights, especially the lack of sunlight irradiance and uneven distribution of sunlight often occur deep inside the room. The light pipe can effectively solve this kind of problem and transmit sunlight directly to the room. The light pipe with the inner diameter of 250mm was fixed, and the working efficiency of light pipes with different shapes and sizes was simulated by computer with illumination angles of 15, 45 and 90. Through simulation, it is found that the illumination angles of light pipes with different shapes and sizes are different at the maximum efficiency. It can match the suitable regional environment according to shape and size characteristics, meet daily office needs, and reduce the assistance of artificial lighting during the day, thus reducing the use of artificial lighting in buildings during the day and reducing the daily power consumption.
Measuring Particle Production Using Tracklets
Authors: Zhang Yuetong , Wang Chenrui , Li Yekun , Liang Xinwen
Published: December 2022

The purpose of the study was to access the particle production. Tracklets was adopted to measure the relationship between centrality ranged from outermost (70–80%) to central (0–5%) collisions and the primary charged-particle density

d
N

c
h

d

η

at

S

N
N

= 2. 76 TeV. It reveals that the dependence of centrality and that measured at lower collision energies (

S

N
N

< 2.76 TeV) are similar.
Analysis of the Charged-particle Multiplicity Density in Centrality from Track Lets
Authors: Shi Xuanyu , Zhang Hanwen , Wang Chengchenyu , Mu Yuanyuan
Published: December 2022

This paper shows the relationship between charged hadron diversity and centrality in hadron Pb-Pb collisions at a certain collision energy(2.76 TeV) per nucleon pair. It is found that the centrality from 70–80% to 0–5%, each normalized charged particle density of participating nucleon pair increases by about twice. The collision of particles in the experiment was simulated by ALICE, a detector dedicating heavy-ion physics at the Large Hadron Collider. This work compares the data sample with models based on different mechanisms for particle production in nuclear collisions. And the error analysis of data in the end of this passage ensures the correctness of the experiment.
Circuit Design for a 4-Channel EEG Pre-processing System with Programmable Output Control Capability
Authors: Hu Yinshi
Published: December 2022

The design of a 4-channel Electro-encephalography (EEG) pre-processing circuit using 0.6m CMOS technology is proposed in this paper. The circuit is divided into two parts. To amplify and differentiate the Alpha, Beta, Delta, and Theta waves from the original EEG signal, a mixed-mode EEG pre-processing system with high gain, low power, and low input noise amplifier and four Gm-C band-pass filters driven by a 1V single power supply are designed. The 4-channel pre-processing system is implemented by connecting four of them in parallel. Second, a digital control circuit consisting of a Serial Input Parallel Output (SIPO) Shift Register and SRAM array is constructed and used to control the output of the pre-processing system, which is powered by a 3.8V power supply.
The Principle and State-of-Art Facilities for PET
Authors: Guo Zhiyuan
Published: December 2022

Since the late 20th century, Positron Emission Tomography (PET) scanners and their hybrid scanners (PET/CT and PET/MRI) offer a path to detect cancer. In this research, the PET scan will be introduced and discussed in multiple dimensions, mainly to explain the principle of PET scan, the state-of-art of PET scans, and the future of PET scans. According to the analysis, from the time that the PET scanner is invented, it not only had a better image quality but also had more functions. It is believed that an intelligent non-radioactive scanner will be achieved in the future due to the development of MRI and artificial intelligence. The main reason for conducting this research is to understand the mechanisms of PET as well as investigate the way to improve the technology itself to avoid the limitations it poses. Overall, these results shed light on guiding further exploration of the next generation of PET scans (e.g., Hybrid PET machines and machine learning).
Parity Violation in Electron Scattering in the E158 experiment at SLAC
Authors: Wang Ronghe
Published: December 2022

This paper explores strategies for correcting measurements for systematic variations and presents the measurements of the parity violation in electron scattering processed by Jupyter Notebook. The analysis used data from the E158 experiment at SLAC and explored strategies for correcting measurements of systematic variations. It also find the measured correlations that translate between a raw asymmetry and corrected asymmetry using Pearson’s correlation method and Multivariate Regression. Factors from weak neutral current interactions, mediated by the Z-boson, that possibly affect the result of the examination of the electroweak theory and the exploration for new dynamics at high-energy scales, are anticipated. The confidence intervals for measured quantities are determined as well.
Origin of the Positron Excess with Pulsar Wind Nebulae
Authors: Xia Hongbo
Published: December 2022

AMS-02 has been measured with unprecedented precision data for the positron flux. These data show that there is an excess of cosmic positrons detected for energies above 10 GeV with respect to the well known secondary production which is due to the collision of cosmic rays with the atoms of the interstellar medium. In this paper we have investigated the possibility that the positron excess is due to the acceleration of positrons and electrons from pulsar wind nebulae. We have first made the assumption that only one pulsar, Geminga, dominates the production of positrons detected at Earth. We find that a spectral index for the injection spectrum of e
+ is needed to fit the data but an efficiency for the conversion of pulsar energy into positron of about 100% is required. This is unphysical since also electrons should be accelerated with the same amount. We have done the more realistic case where all the pulsars reported in the ATNF catalogue produce positrons. We have demonstrated that this case fits well the data with efficiency values of the order of 10-20%. These results imply that pulsar wind nebulae in the Galaxy are likely the main contributors to the positron excess.
The Application of Gravitational Lensing on Observation of Dark Matter Candidates
Authors: Fu Zhenkai , Gao Sirui
Published: December 2022

Basic properties of gravitational lensing could help scientists in detecting the structure of the universe. For instance, the non-luminous dark matter, cannot detected by normal astronomical telescope. The large population low-mass halo which is the cosmological mode of cold dark matter, CDM, locating along the line-of-sight will perturb the strong lensing. In that way, alternation of dark matter from CDM to WDM will be detected by analysis the halo perturbed image. The main proposes of this review is to introduce the history of gravitational lensing, describe the principle of gravitational lensing and state the application of gravitational lensing in modern astrophysics.
Comparison of Joinery Methods on the Strength of Joining Aluminum Alloy and Steel Parts in a Vehicle
Authors: Ding Yichen , Cai Mingxin , Yu Xiaoxuan
Published: December 2022

The modern society greatly utilizes automobiles to fulfill the requirements of transport, and it is logically necessary to research the most efficient joinery method arrangements to construct automobiles. In the contemporary stage of joinery technology, the three mainstream methods are bolting, riveting and welding, and among these joinery methods, bolting could be used for cylinder head and cylinder block, riveting might be the most suitable means for aluminum alloy and steel in vehicle., and welding would be most appropriate for doors, bottom plates and body assemblies. These different methods have various advantages and disadvantages in their applications, as their theories and principles are all but the same. This paper also discussed the methods of joinery that should be used in parts of the automobile body and the future expectation of more novel connection methods that would appear to replace traditional ones.
Film-Cooling Effectiveness Downstream of a Single Row of Holes With Numberical Modeling in ANSYS-Fluent
Authors: Hu Xupei
Published: December 2022

With the increasing thrust of aero-engine, the temperature of turbine leading edge gradually exceeded the limit that materials can bear. Therefore, it is a common way to cool the turbine blades with a reasonable structure of film cooling. In this paper, the single exhaust film hole is taken as the main research object, and the effects of jet mass flow ratio, different temperature of mainstream and jet flow on the cooling effect are studied. The main research method is numerical modeling, and the modeling results are compared with the existing experimental results. The results show that the results have some error in jet’s flow situation and fluctuation in cooling efficiency, but there are still some errors in the calculation of heat transfer efficiency, which may be related to boundary layer separation phenomenon and the accuracy of the corresponding turbulence model.
Filtering method of airborne gravity gradiometer signal based on EMD
Authors: Qian Xuewu , Zhao Liye
Published: December 2022

Gravity gradiometer sensor performance, platform instability and electronic circuit noise can cause serious influence on the weak gravity gradiometry signal, and the noise level is usually one or several times of gravity gradient signal. This paper put forward a method to resolve this problem according to the characteristics of the signal. First of all, filtrate the gravity gradient signal with a band-passing filter. Then, demodulate the output signal of the band-passing filter, at last, remove the gravity gradiometry noise with the empirical mode decomposition (EMD) method. Then the gravity gradiometer signal was tested on the hardware-in-the-loop simulation platform. The experiment results verify that the various harmonic noise can be removed with the method proposed above, and the gravity gradient signal accuracy and gravity gradient space resolution is further improved, the good properties of the method is of high practice and maneuverability.
BSOT: Bandwidth-saving oblivious transfer protocol with confidential computing
Authors: Yang Penglin , Geng Huizheng , Su Li , Lu Li , Yang Tingting
Published: December 2022

Oblivious transfer is a private preserving algorithm for querying sensitive information without known by data owner. The disadvantage of this scheme is that the data owner needs to send amount of redundant data to puzzle the intended information, which will cause the waste of bandwidth. This paper introduces BSOT, a bandwidth-saving oblivious transfer protocol which uses query agent in confidential computing environment in the data source side to reduce bandwidth consumption. In this paper BSOT protocol is defined in CBOR format. Compared to the traditional OT method, this approach could push all the redundant data flow inside the data source instead of transferring by network, and could also restrict the private data from unnecessary leakage.
Multi-user detection for CPM spread system with turbo in VDES
Authors: Wu Feiyu , Zhang Qianwu , Xiang Qian , Yin Huihui , Zhang Xiyan
Published: December 2022

The multi-user detection technology uses the spread sequence, delay, amplitude and phase information of each user to jointly detect users, which can effectively suppress multiple access interference, It is one of the key technologies in satellite communication system to make full use of uplink spectrum resources and improve system performance and capacity. Continuous phase modulation spread signal can adapt to multi-user communication due to the random variation of spread sequence, which is gradually applied to satellite communication. QPSK-CPM spread modulation scheme is adopted in the random access channel of VHF data exchange system. Aiming at the multi-user detection problem of QPSK-CPM spread system, proposing a multi-user detection algorithm based on interference elimination joint Turbo iterative detection based on the characteristics of CPM spread sequence. Compared with the traditional serial interference cancellation algorithm, the algorithm can effectively eliminate the multiple access interference problem caused by user aliasing by using the characteristics of Turbo codes. The theoretical simulation shows that the algorithm has a good detection effect on multi-user aliased signals.
Optical arrangement method of lighting units in switchgear based on partial discharge luminosity distribution characteristics
Authors: Miao Jin , Wu Junfeng , Liu Wei , Huang Fen , Wu Yufeng
Published: December 2022

Partial discharge optical measurement has the characteristics of high sensitivity and strong anti-interference, but its detection effect is greatly affected by the deployment position of the sensor. Therefore, based on the radiation characteristics and transmission characteristics of optical signals, the deployment position of sensors in equipment is optimized. In this paper, an optimal layout scheme of switch cabinet lighting unit based on the distribution characteristics of partial discharge photometric is proposed. Firstly, the optical simulation model of switchgear cable room is designed, and the discharge light source is set at the typical fault location. According to the optical simulation results, the position sensor with high response intensity is selected for different discharge light sources. In order to prove the effectiveness of the layout scheme, the discharge optical detection experiment of switch cabinet was carried out. The results show that the sensor can detect discharge effectively in the selected installation position.
Primary frequency modulation of microgrid based on consistent droop control method
Authors: Hu Linlin , Fu Long
Published: December 2022

The rapid development of new energy sources gradually challenges the frequency stability of power systems. This article focuses on how to realize the frequency modulation control of the power grid under the fluctuation of the power grid. In order to improve the frequency stability of the microgrid system, based on the traditional droop control and consensus algorithm research, this paper proposes a microgrid primary frequency modulation based on the consistency droop control method. This control strategy improves the consistency of the progressive correction term to realize the control of the output of the energy storage unit, and improves the traditional droop controller to quickly restore the stability of the primary frequency. The root locus method verifies the effectiveness and feasibility of the control strategy. The simulation experiment verifies the frequency modulation ability of the proposed control strategy, which not only has a faster adjustment speed and response ability, but also has a strong anti-interference ability.
Design of broadband electromagnetic metamaterials absorption in double-layer resistance film
Authors: Zhu Guanfang , Kang Yifan , Jiang Yanru , Wang Aixia
Published: December 2022

This paper designs a lossy double-layer resistance film absorption structure, which consists of two layers of resistance film and PFA medium alternately superimposed, the bottom of the Cu conductive film is used as the reflection bottom plate, and the metamaterials absorber thickness is 4.267mm. Simulation results show that an absorption rate greater than 90% is achieved in the 6.4-21.1GHz frequency interval, with a maximum absorption peak of 98.5%, a bandwidth reaching 14.6GHz, and a relative bandwidth of up to 106.2%. The wave absorption structure presents polarized insensitive absorption and has good wide-angle incident absorption characteristics. The single-layer resistance film realized periodic and multi-resonant peak narrow-band absorption, with a maximum absorption rate of 99.9%. Based on the software simulation results, the current density field distribution map and impedance characteristics, and the absorption mechanism were analysed.
Adopting integration of multispectral time resolved analysis and graph-based deep learning method in partial discharge type identification
Authors: Xia Changjie , Ren Ming , Wang Kai , Zhang Hongyuan , Guan Haobin , Dong Ming , Zhang Tao , Miao Jin
Published: December 2022

Partial discharge (PD) is treated as one of the major threats for gas insulated switchgear (GIS). By using the new generation multispectral detection sensor named as SiPM-based multispectral discharge sensor (SMDS), the time resolved partial discharge with multispectral information (named as MTRPD) for creeping discharge, suspension discharge and tip discharge, respectively. It indicates that the MTRPD for the specific discharge defect perform unique spectral fingerprints in discharge mode. Based on the graph characteristics of MTRPD, we introduced the convolution neural network (CNN) to implement PD type identification whose overall accuracy of Δqi-Δqi+1 and Δti-Δti+1 were 99.7% and 98.9%, respectively. This paper provides a new technique tool for fine diagnosis of PD independent of phase analysis.
Judgment of Low-voltage leakage fault type and fault point finding method in power distribution platform area
Authors: Hong Gang , Zhu Song , Huang Hengying , Wei Xiangxiang
Published: December 2022

In the development of modern social economy and technological innovation, the technical application of the power industry is more and more demanding, and researchers have gradually strengthened the judgment and search technology research of low-voltage leakage fault type in distribution platform area. From the perspective of practical application, when the leakage fault occurs in the low-voltage line, it is necessary to find the area as soon as possible and put forward an effective solution, so as to avoid further expansion of the fault problem. In this paper, on the basis of understanding the causes of low-voltage leakage faults in distribution platform area, according to the various judgment schemes proposed by scholars at home and abroad, an intelligent fault identification and positioning system is deeply discussed, so as to clarify the types of faults and find methods. Finally, the practical results show that the causes of leakage faults are different, and the practical judgment and search methods should be targeted and diversified.
Monitoring and prediction of thermal failure of high-voltage switchgear insulation materials by studying the thermodynamic properties of FR-4 epoxy resin and the characteristic gas of thermal decomposition
Authors: Hu Mengzhu , Tang Bin , Liang Qinqin , Luo Zongchang , Luo Chuansheng , Wang Jialin , Zhang Longfei , Zhu Liping
Published: December 2022

FR-4 epoxy resin is a common material used as internal parts in high voltage switchgear. In this paper, we adopted the accelerated thermal aging method to explore the thermal aging behavior of FR-4 epoxy resin, simulating the practical application of this material in high voltage switch. The effects of thermal aging on the thermodynamic properties and thermal decomposition characteristic gases of FR-4 epoxy resin were characterized by FT-IR, DSC, TG and GC-MS analyses. The experiment results showed that thermal aging could destroy the internal crystal structure of FR-4 epoxy resin, which could lead to this material easier to be decomposed after heating. We also detected that the thermal decomposition rate of FR-4 epoxy resin aging was greatly accelerated compared with the materials that had not been aged. In addition, unaged FR-4 epoxy resin could release 9 main volatile gases under 120°C, and irreversible defects or structural damages occurred in the materials along with the volatilization of small organic molecules. Furthermore, after continuous thermal aging at 120 °C for 672 h, the molecules of FR-4 epoxy resin were more cracked and volatilized, we observed a more obvious phenomenon of thermal decomposition in this materials. In total, we compared the types of thermal decomposition gases and the decomposion mechanism of aged and unaged FR-4 epoxy resin. In application, our results can provide reference for condition monitoring and fault prediction for this material in high voltage switchgear in the future.
Power transformers fault diagnosis using graph neural networks based on dissolved gas data
Authors: Mao Weiyun , Wei Bengang , Xu Xiangyi , Chen Lu , Wu Tianyi , Peng Zhengrui , Ren Chen
Published: December 2022

The Dissolved Gas Analysis (DGA) is an important way and is now extensively used to detect incipient faults in oil-immersed transformers. Some conventional methods for DGA, such as the Three-Ratio Method, usually misunderstood the gas data and failed to accurately detect multiple fault combinations. Recently, most researchers investigating DGA have utilized machine learning algorithms to improve the accuracy of fault diagnosis. The dissolved gas data are usually treated as tabular data by using machine learning algorithms to achieve better results compared to conventional methods. However, those machine learning methods ignore the internal connection of the dissolved gas data in the time dimension. Therefore, this paper adopted a new DGA method for transformer fault diagnosis based on Graph Neural Network (GNN) and Multivariate Time Series (MTS) model. The results finally showed that the model outperforms the existing machine learning baseline methods and conventional methods on the dataset.
Molecular dynamics simulation of inhomogeneous density distribution mechanism of Ultra-Thin perfluoro sulfonic acid ionomer films on Triple-phase interface of PEM fuel cells
Authors: Wan Yue , Qiu Diankai , Yi Peiyun , Peng Linfa , Lai Xinmin
Published: December 2022

The proton exchange membrane (PEM) fuel cell is a clean power generation component with high energy conversion rate and high energy density. The triple-phase interfaces of catalytic layer are where the electrochemical reaction occurs in proton exchange membrane (PEM) fuel cell, and its distribution directly affect the reactivity. The triple-phase interface is a nano-thick perfluorosul-fonic acid ionomer (PFSA) film that covers the catalyst particles. When the density of the ultra-thin PFSA film is not uniform, the gas transport resistance increases significantly, which is not conducive to the progress of reaction. However, ultra-thin PFSA film will have inhomogeneous density distribution due to the influence of forming process. Therefore, how to design the process to improve density distribution of ultra-thin films is an urgent problem. Molecular dynamics simulation model is built to study the influence of manufacturing process on inhomogeneous distribution of ultra-thin PFSA film, and the microscopic mechanism is revealed.
A Two-level clustering chain energy heterogeneous routing protocol for WSN
Authors: Hu Mei , Wang Yongxi
Published: December 2022

In view of the disadvantages of high energy consumption, short life cycle, low throughput and no application correlation in heterogeneous WSN, a two-level clustering chain routing protocol is proposed under the heterogeneous WSN of intelligent water-saving irrigation system of ecological agriculture in Hexi Gobi. The irrigation subnets are divides into clusters according to the actual layout in the wireless network and the nodes in the cluster form the chain on the basis of the minimum distance. The two-level cluster headers in reserve are selected by rate of the remaining energy of terminal nodes in cluster vs. average energy in local region. Eventually the level clusters heads and the two-level cluster headers are chosen according to the largest ratio of the remaining energy to the distance between the terminal nodes and the base station. Results in simulation show that the proposed algorithm is superior to PEGASIS and SEP in energy consumption, life cycle and throughput.
Implementation of CCSDS lossless compression algorithm for geomagnetic data
Authors: Zhang Yue , Li Li , Huang Chengbin , Wang Jinhua
Published: December 2022

Long-term geomagnetic data monitoring will generate a huge amount of data, and compression algorithms will be required to reduce the amount of data to save data storage and transmission expenses. To adapt to the application with limited resources, the CCSDS lossless compression algorithm is applied to geomagnetic data measurement in our work. This compression algorithm is made up of two parts: a preprocessor and an adaptive entropy coder. In this study, the unit-delay predictor is chosen as the preprocessor based on the properties of the geomagnetic signal, and the adaptive entropy coder chooses a suitable compression algorithm for geomagnetic data. A 14-hour continuous measurement was performed. The results reveal that when the block size is set to 64, the algorithm can obtain a compression ratio in the geomagnetic field of 0.269 to 0.318. Furthermore, the number of chosen encoding options for three-axis magnetic data was counted.
Hazard assessment of copper(I) oxide nanoparticles obtained by reduction in the presence of polymer protector
Authors: Morenko I V , Yu Isaeva I , Eliseeva E A , Yu Ostaeva G
Published: December 2022

The article presents the results of a study of the danger of copper (I) oxide nanoparticles for the health of living organisms and ecological systems. A sol containing Cu2O nanoparticles was obtained by reducing metal ions in the presence of a polymer protector. The sol was then further processed to purify and separate it into its components. The products of synthesis and processing were examined using transmission electron microscopy, scanning electron microscopy, and X-ray diffraction. It has been established that as a result of processing Cu2O nanoparticles of spherical shape and a diameter of 34-149 nm (average diameter = 62 nm) were obtained. Factors affecting the hazard of this nanomaterial were identified. Using mathematical modeling methods, it was determined that the obtained nanoparticles have a hazard coefficient D= 1.773 in the case of laboratory production (medium level of potential hazard), D= 1.874 in the industrial production case (high level of potential hazard).
Reflection of the individual multipoles fields from a flat substrate in the angular spectrum approach
Authors: Kislov D
Published: December 2022

In this report, we give the derivation of the electromagnetic field of multipoles over a substrate, using the angular spectrum representation. The multipole series up to the electric quadrupole is considered. If necessary, this approach can easily be extended to multipoles of any order. As a result, analytical expressions for the scattered and reflected multipole fields as an infinite sum of plane waves of different polarizations are obtained.
Positional strategies in fractional order differential games
Authors: Mamatov Mashrabjon , Alimov Khakim , Esonov Egamberdi
Published: December 2022

Problems of the branch of mathematics called differential games, which today find their versatile applications in physics and engineering, are devoted to the construction of chase control when the states of the object are known only at given times in advance. Sufficient conditions for the possibility of completing the pursuit in the sense of hitting a small neighborhood of the terminal set are obtained. A method is indicated for constructing a positional strategy of the pursuer that infers a trajectory to a given neighborhood of the terminal set by the time determined by the first direct method of the theory differential pursuit games. In this case, the chasing party cannot use the fleeing player’s control to build its control; therefore, according to the condition of the problem, the chaser builds its control if it knows the state of the object at the given times in advance.
Database development to automate statistical analysis and build regression models of electric capacitance for magnetic nanofluid microlayers
Authors: Demin M S , Morozova T F , Bondarchuk A Yu
Published: December 2022

The authors review the mathematical modeling methods for complex systems. To optimize the modeling, the authors developed a database on the electric capacitance of a cell with a magnetic nanofluid microlayer. The statistical analysis resulted in the justified acceptance of the IBM SPSS Statistics software for the statistical processing of the data and the construction of the regression models for the changes in the electric capacity of magnetic nanofluid microlayers
The incremental learning algorithm for compartmental spiking neuron model
Authors: Eremenko E A , Korsakov A M , Bakhshiev A V
Published: December 2022

Within the framework of the neuromorphic approach, a compartmental spiking neuron model was developed. The compartmental spiking neuron model was used to solve the classification problem using a small training set. However, despite the biological inspiration of the model, the used compartmental spiking neuron model was unable to learn new instances online. The structural learning algorithm used limited the model to use only in offline scenarios, while there are a large number of tasks where the ability to adapt to new data coming in during model operation and the ability to work with data distributions that change over time are necessary. Based on this, the task of online restructuring of the model is relevant. In this paper, we propose a new algorithm for training a compartmental spiking neuron model, which allows the model to be used in incremental learning scenarios.
Ensuring the uniformity of oscillations of a flat membrane by sources of ultrasonic impact
Authors: Khmelev V N , Golykh R N , Tsyganok S N , Barsukov A R
Published: December 2022

The article presents the results of studies aimed at ensuring the uniformity of vibrations of a flat membrane by sources of ultrasonic exposure. The relevance of the conducted research lies in the fact that for the effective implementation of physical and physicochemical processes in thin liquid films, it is necessary to ensure the maximum uniformity of the effect over the entire surface area of the spreading film. The main problem is that today there are no ultrasound emitters that are able to form a uniform distribution of vibrations over the entire impact plane and thereby ensure the uniformity of the technological process. The vibration concentrators and reciprocating working tools that currently exist are distinguished by a limited radiation surface. This is due to the fact that attempts to increase the area of the radiating surface lead to the need to use multipackage piezoelectric transducers. However, in this case, it is not possible to ensure the in-phase oscillations of each packet (due to wave processes inside the emitter material) and, therefore, for large surface areas, the oscillations turn out to be inhomogeneous or have a small amplitude. The authors propose a mathematical model that will allow optimizing the location of the emitters to ensure maximum uniformity of oscillations of a flat surface. The proposed model makes it possible to identify the optimal configurations of radiators, which provide the smallest dispersion of the oscillation amplitude of the free surface (on which there are no fixed radiators).
Implementation of processor cores of a fault-tolerant control system on FPGA under external control
Authors: Saramud M V , Karaseva M V , Kovalev I V , Losev V V
Published: December 2022

The paper describes the choice of a technical solution for the implementation of a fault-tolerant real-time control system under external control. The main idea of the method is to introduce an external control block of the main control system that includes a watchdog and a backup decision-making algorithm. This block was supposed to be executed on an external FPGA-based block. The main system was supposed to be executed on the CPU. The paper proposes a variant of creating the entire system on a single FPGA. It implements both the processor cores for the operation of the main control system and control block. Various variants of cores for implementation on FPGA are considered. The paper studies suitable projects of processor cores for implementation on FPGA. It is concluded that the LEON series cores are suitable for the problem of building a fault-tolerant control system, since they already have technical solutions to improve fault tolerance. It is concluded that the proposed approach to building a fault-tolerant control system with external control can be fully implemented on a single FPGA. It has some advantages over implementation on separate blocks.
Principals of digital system design debugging decomposition
Authors: Ivannikov Alexander
Published: December 2022

Up-to-date digital integrated circuits become more and more complicated. The amount of its elements increases enormously, sizes of the elements become very small. That is why the task of digital system design debugging becomes more and more complicated. So, digital system design debugging decomposition is required. In the paper design debugging decomposition by simulation is considered. The classification of debugging decomposition methods and its algebraic models are presented. The following decomposition methods are described: vertical and horizontal structure decomposition, functional decomposition, decomposition based on error types.
Ways of deactivation of the electron excitation energy of arylethylenes and arylpolyenes in solutions
Authors: Astanov Salih
Published: December 2022

Experimentally and quantum chemical calculations have established that the main ways of deactivation of the electron excitation energy for 4,4′-substituted AE with electronic acceptor derivatives are, along with trans–sic and isomerization, the transition of an electron from a singlet excited state to the ground state with fluorescent radiation. For molecules with electrodonor substituents, an intercombination S-T electron transition occurs with the observation of phosphorescent radiation. It was found that an increase in the number of ethylene bonds in the structure of aryl-polyene processes without radiative internal conversion deactivation of energy.
Application of data correlation analysis in the problem of emulation of spacecraft sensors
Authors: Shishkin O G , Khachumov V M , Emelyanova Yu G
Published: December 2022

The article deals with the issues of building an emulator of a failed sensor, which is necessary to maintain the life cycle of a small spacecraft. Such an emulator is proposed to be built on the basis of a stable correlation of its data with data from other spacecraft sensors. On the basis of the performed studies, estimates of the root-mean-square deviation of the restored telemetry data from the reference values were obtained. It is shown that the proposed approach provides real-time data recovery with acceptable accuracy.
Systems monitoring based on robust estimation of stochastic time series models
Authors: Tyrsin A N , Golovanov O A
Published: December 2022

The problem of system monitoring under conditions of stochastic data heterogeneity based on time series models is considered. The stability of monitoring is proposed to be ensured through the use of convex-concave loss functions. An algorithm for estimating the variance of the main error distribution is proposed. This allows using robust procedures for estimating the parameters of stochastic time series models without a priori information about the variance value of the main error distribution. Using the Monte Carlo statistical test method, the estimates of the proposed robust methods are compared with the known methods of least squares, least modules, and Huber. It is shown that the introduced robust estimates of the parameters of stochastic models of time series win in accuracy and allow increasing the reliability of monitoring the state of systems.
Predictive state analytics of gas pumping units
Authors: Krasnov A N , Prakhova M Yu
Published: December 2022

Diagnostics of the technical condition of equipment is an important factor in the efficiency of any production. This fully applies to the oil and gas industry with its huge fleet of pumping and compressor equipment, the downtime and repair of which, as a result of any accidents, causes significant damage to enterprises. The development of digital technologies, such as Big Data, IIoT, and machine learning makes it possible to move on to the so-called predictive or predictive analytics, which makes it possible, based on the analysis of trends in a large number of variables, in real time to predict the possible onset of an emergency. The article considers the possibility of building a local system of predictive analytics for a gas compressor unit based on the analysis of its behavior before the accident, during the accident and after it. The predictive analytics system (PSA) was built based on the real data of the unit, on which surge occurred due to fatigue failure of the high-pressure compressor elements. The evaluation of the resulting model showed its high accuracy even under conditions of a limited set of initial data. The use of such systems makes it possible to avoid accidents that occur as a result of a change in the technical condition of the equipment and are absent, in connection with this, in emergency protection scenarios.
Correlation analysis of the results of remote sensing of the atmosphere by a three-band microwave radiometric system
Authors: Fedoseeva E V , Rostokin I N , Shchukin G G , Kholodov I Yu
Published: December 2022

The results of the correlation analysis of the data of measurements of radio-thermal radiation of heterogeneous atmosphere with precipitation by the three-band microwave radiometric system with reception along one direction to the common aperture of the mirror antenna at three frequencies 7.5 GHz, 10 GHz, 22 GHz are presented. Correlation coefficients of output signals of all receiving channels of the system with the results of measurements of meteorological parameters - temperature, intensity of precipitation, humidity of the surface layer of the atmosphere, obtained from the meteorological stations of five cities, nearest to the location of the measuring microwave radiometric complex are calculated. The dependence of measurement results with and without compensation for the influence of external influences at different frequencies on the degree of homogeneity of meteorological parameters of the atmosphere and on the presence of local inhomogeneities in the atmosphere and their remoteness from the location of the measuring microwave radiometric complex is shown.
Mathematical model of a valve converter based on a parallel current inverter with an adjustable output voltage of an improved form
Authors: Umarov Shukhrat , Sapaev Khushnud
Published: December 2022

The results of development of mathematical model and structural diagram of transient processes calculation algorithm of the valve converter based on single-phase current inverter, operating both in continuous and intermittent mode of input current are given in the article. Mathematical model of DC-AC valve converter with adjustable output voltage on the basis of parallel autonomous current inverter with inductive-thyristor compensating device is made on the basis of the operator method. Instead of traditional approach related to making operator substitution diagram for each possible state of power circuit proposed to use universal substitution diagrams equivalent to several states of the power circuit involved in the development of electromagnetic processes. Analysis of possible power circuit structures, which can participate in development of transient processes has shown that six power circuit structures participate in formation of process, which can be brought to two universal operator substitution diagrams. Application of universal replacement schemes, preserving advantages of the operator method, makes it possible to reduce the size of the model, reduce the required volume and time of calculations, allows to perform necessary calculations of circuit parameters in a wide range, taking into account the excitation and regulation method and to carry out the appropriate selection of elements as a result. The proposed structural diagram of algorithm of calculation of transient process is made on the basis of performance of boundary conditions of stages of development of process and revealing of sequence of change of types of equivalent circuits on intervals of clocking. The algorithm allows making calculation of transients at change of an input voltage of the inverter, at change of loading, and also at simultaneous change of an input voltage and loading. The developed mathematical model and algorithm provide the procedure of parametric synthesis of inverter elements with high accuracy.
Simulation of dynamic processes when a soil-throwing drum meets an obstacle
Authors: Gnusov Maksim A , Drapaluk Michael V , Druchinin Denis Yu , Lysych Michael N , Pozdnyakov Evgeniy V , Petkov Alexander F
Published: December 2022

The problem of combating forest fires is very relevant to this day. The development of machines designed to extinguish and prevent uncontrolled forest fires, especially in waterless areas, is the most important area of scientific research. The article presents scientific research on simulation modeling of the interaction of a soil-marking drum with obstacles of two types: stones and logging residues. For the study, a simulation method was used in the 3D-CAD environment of the SolidWorks Simulation system, which made it possible to conduct a virtual experiment of a solid model and determine the behavior under static and dynamic loads that occur in emergency situations. The purpose of the work was to develop a 3D model of a soil-throwing drum machine for extinguishing and preventing forest fires to conduct simulation studies on a virtual stand to determine the dynamic loads in contact with obstacles of the soil-throwing drum blades based on the created solid model. For the process of studying the soil-marking drum when encountering obstacles in the form of logging residues and stony inclusions, an imitation virtual stand was created. The paper presents the results of the analysis of data obtained on the basis of simulation modeling.