bluuebunny/crossref_metadata_2025_split huggingface dataset:
On the boundary regularity of solutions of linear elliptic partial differential equations
Authors: Yu Xuemei 
Published: December 2022

Abstract
Regularity refers to the properties of the solution, including the smoothness, symmetry, and asymptotic of the solution. It is an important part of the theoretical study of partial differential equations. It plays a key role in the existence, uniqueness, stability, and smoothness of the theoretical solutions of partial differential equations. It is an important basis for understanding the nature of partial differential equations and their corresponding physical reality. This paper studies the boundary regularity of elliptic partial differential equations, including the problem of the oblique boundary of completely nonlinear equations. It is well known that the regularity of the solution at the region boundary depends not only on the equation, but also on the geometric properties of the region boundary. This is why boundary regularity is complicated. This paper is to obtain the regularity of the solution at the region boundary under different boundary conditions.
Prediction of Aging Population in Guangdong Province Based on Metabolic GM (1,1) Model
Authors: Zhao Zhiqin , Wang Qiang 
Published: December 2022

Abstract
With the deepening of reform and opening up, Guangdong’s economic vitality continues to be maintained. People’s living standards and medical conditions have further improved, the population’s life expectancy has gradually increased, and the aging of the population has intensified. With the data of the elderly population aged 65 and above in Guangdong Province from 2011 to 2020, a metabolic GM (1,1) model is established based on the grey system theory, and the predictive value of the established model is tested. The results show: Q= 0.005189 ≤ 0.01; the mean square deviation ratio c= 0.064 ≤ 0.35; the test accuracy of the model is class I. The metabolic GM (1,1) model predicts that the population aged 65 and over in Guangdong Province will continue to increase in the next five years, and the problem of population aging is still severe. Therefore, it is necessary to change the situation. In the past, solutions to population aging only focused on the aspects of changing the population policy and the pension system. Now, we should fully consider the interrelationship of population aging on economic growth, savings and consumption, macroeconomic balance, and other indicators. We should actively respond to the urgent reality of the population aging in Guangdong with a systematic strategy.
An Exploration of Brannan’s Coefficient Conjecture
Authors: Cai Wenben 
Published: December 2022

Abstract
Complex analysis of a single variable is a type of mathematical analysis that observe properties for holomorphic functions. Over decades of development, complex analysis nowadays has played a more and more important role in algebraic geometry, fluid dynamics, quantum mechanics, and so on. This paper is to elaborate the Brannan’s coefficient conjecture, which was first proposed by D.A Brannan, J.G. Clunie, and W.E Kirwam in their paper on the coefficient problem for functions of bounded boundary rotation in 1973. The purpose of this paper is to give a detailed review and exploration of complicated but elegant proofs by D. Aharonov and S. Friedland. This paper mainly focuses on proving the inequality

(
1
+
α
x
)

n

(
1
−
x
)

p

≤

(
1
+
x
)

n

(
1
−
x
)

p

for p > 0 |α| = 1 within condition n ≥ 1, which was derived from Brannan’s coefficient conjecture. The proof of the inequality is done by dividing the techniques of complex numbers, trigonometric functions, binomial expansions, and other mathematical formulas into three different cases.
Neural Network for Solving Nonlinear Parabolic Differential Equations
Authors: Zhang Hong , Huang Hongying 
Published: December 2022

Abstract
We develop a cell-average-based neural network (CANN) method to compute nonlinear differential equations. Using feedforward networks, we can train average solutions from t0
+ Δt with initial values. In order to find the optimal parameters for the network, in combination with supervised training, we use a BP algorithm. By the trained network, we may compute the approximate solutions at the time t

n+1 with the ones at time tn
. Numerical results show CANN method permits a very large time step size for solution evolution.
Security Control for Time-Varying Delay Systems Based on Random Switching Moving Defense Method in Cyber-Physical Environment
Authors: Zhong Fuli 
Published: December 2022

Abstract
With the high digitization, informatization, and networking of practical complex systems, the security and reliability issue of systems control in the cyber-physical environment is becoming more and more critical, especially under the background of rampant network attacks nowadays. The security control for time-varying delay systems based on random switching moving defense method in a cyber-physical environment is studied in this paper. First, the security control model of one class of time-varying delay dynamic systems considering the actuator and controller attack problem is presented; second, controller design based on switching strategy for moving defense is studied; and then the security control scheme for time-varying delay systems based on random switching moving defense is presented for dealing with cyber attacks from malicious adversaries. Finally, multiple simulation results are presented to show the effectiveness of the proposed scheme.
Uncertainty Analysis of Accident Vehicle Speed Based on Tire Marks
Authors: Zhu Ke 
Published: December 2022

Abstract
Accidents without video information often cannot obtain trace information accurately, and it is difficult to accurately select parameters when using the tire marks formula, resulting in inaccurate results calculated during research and analysis. To obtain more authentic and reliable analysis results and improve the reliability and authority of accident identification and treatment, it is necessary to reflect the measurement error into the conclusion of calculation and analysis more completely and reliably, to ensure that the true value of the calculation result is within the calculation range of theoretical error. Therefore, through the Monte Carlo method and Subinterval method, the uncertainty analysis of the accident speed is carried out, and the accident vehicle speed is restored more accurately, which is conducive to the accident handling personnel to judge and analyze the accident speed.
Internal Ballistic Modeling and Simulation Analysis of High-low Pressure Low-overload Launch of Unmanned Aircraft
Authors: Hu Yuantao , Yang Guolai 
Published: December 2022

Abstract
The low-overload launch is an important research direction in weapon launch. In this paper, a new low-overload launch method is designed by using the piston-type high-low pressure launch principle combined with the secondary launch principle. Based on the classical internal ballistic equations and multi-body dynamics equations, the internal ballistic model of this low overload launch system is established. A joint simulation model based on MATLAB and RecurDyn is constructed to simulate the internal ballistic state during the launch process. The sensitivity of each parameter change of the high-low pressure system to the launch overload is also studied. The results show that the maximum low-pressure chamber pressure of the low overload launcher in this paper is reduced by 62% compared to the conventional internal ballistic pressure, the saturation of the pressure curve is also improved, and the muzzle velocity is accelerated; the maximum overload is reduced by 65%, which can meet the requirements of muzzle initial velocity and low overload when launching unmanned aircraft.
Network Data Encryption Transmission Method Based on the Noekeon Algorithm
Authors: Tian Jiong , Hu Changwu , Wang Xian , Fan Zesen 
Published: December 2022

Abstract
Given the problem of a high bit error rate in the current network data transmission process, to improve the security and confidentiality of data transmission, the Noekeon algorithm is introduced to carry out the design and research of network data encryption transmission methods. Combined with the multi-node communication technology, a multi-node network data transmission model and a topological structure model are established. Based on the Noekeon algorithm, the Gamma module and diffusion layer are used to encrypt the network data. Through the network data encryption transmission and the multi-node frequency synchronization compensation, the encrypted network data are transmitted by VPN networking. The comparative experiments show that the new transmission method can control the bit error rate below 10% in practical applications, which is significantly better than the previous transmission methods. The new transmission method can promote the security of network data transmission and protect users’ privacy.
Investigation of Displacement and Fracture Characteristics of Surrounding Rock under Strong Unloading Action
Authors: Lin Qindong , Feng Chun , Gan Yundan , Zhang Yulei , Yuan Jianfei , Jiang Haiyan , Han Lu 
Published: December 2022

Abstract
The rock burst causes a significant threat to the construction of the deep-buried tunnel, and the displacement and fracture evolution characteristics of surrounding rock are investigated during the rock burst. First, the full-time numerical simulation of the rock burst is conducted. Then, the displacement evolution characteristic of the rock is analyzed. Finally, the fracture evolution characteristic of the rock is analyzed. The results indicate that more and more surrounding rock near the left straight-wall segment undergoes fracture and movement with the increase of time, and the rock that heaps up in the tunnel mainly comes from the middle-upper part. With the increase of time, the volume V
r of rock moving into the tunnel and the fracture ratio α keep increasing, while the growth trends of V
r and α decay. The fracture degree of rock near the left straight-wall segment is the most severe, and the fracture area gradually expands with the increase of time.
The Retrospect and Prospect of GaN-Based Schottky Diode
Authors: Su Xinran 
Published: December 2022

Abstract
In the 21st century, with the continuous progress of human society and the continuous upgrading of the integrated circuit industry in recent years, the rapid development of modern science and technology makes us have higher and higher requirements for semiconductor products in our life and production. Compared with the first generation and the second generation of semiconductors, the third generation of semiconductors represented by GaN relies on its high electron mobility, bandgap width, electron saturation speed, high-temperature resistance, radiation resistance, and other suitable material properties. It has more and more extensive application prospects in the research field of microwave high-power devices. Today, the introduction of semiconductors in electronics improves the energy efficiency of equipments and modules. Gallium nitride (GaN) - based schottky diodes have broad application prospects in the next generation of schottky diodes due to their excellent performance. However, because of some technical concerns, these materials have not been fully developed. This work briefly summarized some science and technology related to GaN-Based Schottky Diode. A special focus will be put on the advantages and disadvantages of GaN-Based Schottky Diode, discussing some modern improved designs. Finally, possible breakthroughs of GaN-Based Schottky Diode will be summarized.
Transverse Momentum Dependence on Fourier Elliptic and Triangular Flow Harmonics in Mid-Central Pbpb Collisions at

SNN=2.76TeV
Authors: Zhang Shi , Wang Zimo , Li Xinwei , Shen Ruolin , Ouyang Chengxuan 
Published: December 2022

Abstract
We have collected particle collision data from the experiment using CMS apparatus, where we studied charged ions in the nucleus-to-nucleus collision’s PbPb branch in Pb at the 2.76 TeV energy scale. So far for the present work, we report the anisotropy of the thermal observational flux in lead-lead nucleon collisions at sqrt = 2.76 TeV. We observed that the collisions produced a large ion azimuth angle ranging from −π to π radian and a pseudo-conductance ranging from -2.6 to 2.6. In this work, we report the correlation function of transverse momentum, Pt
, Δη, and ΔΦ over a wide range of centroids. When the transverse momentum is about 1-2 GeV/c and Δη is in range -1 to 1, we observe a jet peak in the η and Φ correlation plot as the centrality increases. In the case of ν
2, which is an elliptic current signal, we measured it with a 4-part correlation method in the 40-50% centrality class. Asymptotic angular correlations in the far range have been studied by Fourier decomposition on the product of anisotropies when the cross-correlation is equal to 3-3.5 GeV/c. The obtained Fourier coefficients are factorized into the singular product of -ion Φ anisotropies. The assumptions of the hydrodynamic model with the shear viscosity correlation increase accordingly.
Research on Dynamic Nonlinearity of Materials Based on Tensile Test
Authors: Liang Enqiang , Kong Jiali , Zheng Minghui , Li Shengtao 
Published: December 2022

Abstract
The collision impact process of a structure is a complex nonlinear dynamic response process, and the key factor to ensure the accuracy of the calculation results when calculating the simulation collision problem is the definition of the dynamic nonlinear parameters of the material during the simulation analysis, and there is no uniform treatment for the collision impact problem. Based on Q235 steel, quasi-static tensile and high-speed tensile tests were carried out, and the material parameters were calibrated to meet the requirements of the collision simulation calculation based on the test data, considering the material strain rate sensitivity and material hardening properties. The research results can be used as a reference for the simulation of large structure impact problems.
Research on wear and high cycle fatigue performance of ceramic coatings produced on Ti-6Al-4V alloy by micro-arc oxidation
Authors: Fu Yuzhu 
Published: December 2022

Abstract
Ceramic coatings were produced on the surface of Ti-6Al-4V titanium alloy by Micro-Arc Oxidation (MAO) technique. The morphology and phases of coatings were investigated by scanning electron microscopy (SEM), and X-ray diffraction (XRD) technologies. The friction and high cycle fatigue properties were tested in coated and uncoated specimens. The results show that the MAO coatings were mainly composed of the anatase TiO2 phase, which grows in-suit on the surface of the substrate material. There was no transition layer between the coatings and the substrate, and a high bonding strength was obtained. The anti-abrasion properties of the coated specimens were improved because of the high hardness of ceramic coatings. MAO generates many micro-pores. During fatigue loading, the micropores act as notches to cause stress concentration, which can decrease the fatigue life of substrate material.
Analysis of loose roll mark of hot-rolled pickling alloyed galvanized automobile sheet
Authors: Zuo Rong , Xiong Taotao , Chen Ming , Zhu Bixue , Li Liejun 
Published: December 2022

Abstract
The loose coil mark of hot-rolled pickling alloyed galvanized automobile plate is one of the main defects affecting the quality of steel plates. In this paper, the composition of the loose coil mark and the coiling process parameters of the hot-rolled pickling galvanized sheet was analyzed. The results showed that the main reasons for the loose coil marks were insufficient friction between the coiler mandrel and the strip, and the coiling tension of the lead head was unstable. By increasing the lead rate of head coiling speed to 15 mpm and increasing the crimp tension limit, the loose coil marks of hot-rolled pickling alloyed galvanized automobile plate were significantly reduced, and the quality of the steel plate was significantly improved. The unqualified steel plate caused by the defect of plate loose coil marks was downgraded from 100 t/month to 15 t/month.
Effect of deep cooling times on the architecture and performance of DLC coating system
Authors: Bi Jun , Tian XianLiang , Gao Yuan , Li Liejun 
Published: December 2022

Abstract
At present, the research on deep cooling times mainly focuses on the influence of a certain material. The research on the deep cooling treatment process of the coating composite system focuses on the insulation time, deep cooling temperature, and cooling rate, and there are few studies on the influence of deep cooling times on the coating composite system. This paper preliminarily explored the influence of the cryogenic treatment process changing cryogenic times on the structure and properties of the diamond-like carbon film (DLC) coating on an M35 high-speed steel surface under the condition of a certain total holding time. When two cryogenic treatments were carried out at -140°C and -196°C, the content of the SP3 hybrid bond decreased. The bonding force of DLC coating is improved after several cryogenic treatments, but the wear resistance of DLC coating decreases with the further increase of cryogenic times. This process has certain reference significance for improving the bonding force and wear resistance of DLC coating.
Analysis of the thermodynamic characteristics of particle reinforced multifarious compositions
Authors: Xiang Yu 
Published: December 2022

Abstract
The mechanical characteristics of particle-reinforced multifarious compositions are virtually hinged on the characteristics of matrix materials, particles, and the characteristics of the interface between particles. The composite material can be used to improve the disadvantages of a single raw material and expand the scope of application. Multifarious compositions have the advantages, such as high specific strength, high fatigue resistance, and high specific stiffness. For this reason, it is widely and specifically used in aviation manufacturing, aerospace technology, and transportation. Composite materials, titanium alloy, aluminum alloy, and alloy steel have become the main structural materials for aircraft body manufacturing, which is conducive to the improvement of fuel efficiency, simplifying system installation, and shortening assembly time. This research introduces a three-phase theoretical model to analyze the thermodynamic characteristics of particle-reinforced multifarious compositions. The effects of particle volume fraction, particle shape, and interface layer thickness on particle thermodynamic characteristics are analyzed and described.
Study on the hot deformation behavior of SAE8620RH gear steel
Authors: Chen Songjun , Li Liejun , Li Jiao , Xie Dongsheng , Zhu Chenghui 
Published: December 2022

Abstract
The rapid development of new energy vehicles has put forward higher requirements for the performance and precision of high-end gears. Reasonable thermal deformation parameters play a major role in controlling mechanical properties of gear steel. The stress-strain curves of the SAE8620RH gear steel were obtained by a single-pass compression test combined with the Gleeble-3800 simulator, and the effect of thermal deformation parameters on dynamic softening behaviour was analyzed. Results showed that with deformation temperatures increasing, dynamic softening mechanism changed from dynamic recovery to dynamic recrystallization. Increasing the strain rate inhibited dynamic recrystallization. However, under the condition that full dynamic recrystallization could have occurred; Higher strain rates can produce finer recrystallized grains. In addition, dynamic recrystallization grains were unevenly distributed and appeared to have abnormal grain growth at low strain rate and high temperatures.
Effects of solution treatment on microstructures and properties of Mg-Nd-Zn-Y-Zr alloy
Authors: Su Zaijun , Zhang Longguang , Zou Liming , Chen Huilie , Li Haiquan , Li Rongrun 
Published: December 2022

Abstract
The effects of solution treatment on microstructures and properties of Mg-2.4Nd-0.2Zn-6.0Y-0.5Zr alloy were studied. The research conclusions show that the cast alloy is comprised of α-Mg, Mg12Nd, Mg24Y5, MgYx, α-Zr phases. After solution treatment, the Mg12Nd and Mg24Y5 phases gradually dissolve into the matrix, while there are also MgYx and α-Zr phases near the grain boundary. The weakening of the second phases strengthening and fine grain strengthening offset the solid solution strengthening, resulting in a slight improvement of the tensile strength and yield strength. However, the elongation of alloy increases by 125%, which attributes to the elimination of the crack sources. The best solution treatment for the alloy is 500°C × 8 h.
Numerical simulation and flat tensile strength optimization of metal zipper
Authors: Zeng Wenhao , Mao Luyao , Huang Dong , Chen Qiyu , Zhang Huawei 
Published: December 2022

Abstract
Metal zippers are widely used in various engineering fields because of their compact structure, simple principle, and convenience. The flat pull strength is one of the most important indexes to judge the performance of a zipper. The methods used to optimize and improve the flat pull strength of a zipper are important for obtaining higher reliability. In this paper, the method of finite element analysis is used to establish the numerical model of the flat tensile strength for a 5# metal zipper. Relevant numerical results were comparatively discussed with experimental results. Based on the constructed finite element model, the design of the zipper pull strength was optimized. The influences of the chain tooth characteristic parameters such as the thickness of the chain tooth, the height of the chain tooth, the width of the chain tooth, and the spacing between the chain teeth on the pull strength were analyzed. The results show a good agreement between numerical simulation results and testing results. The optimization of characteristic parameters for the 5# metal zipper teeth was subsequently performed. The optimized structure indeed increases the frictional contact force between the teeth and enables the meshing between the teeth more consistent which eventually improves the flat pull strength.
Analysis of material selection trend of the automobile control arm
Authors: Song Tao , Xu Shujie , He Shaoqing 
Published: December 2022

Abstract
The material selection of the automobile control arm is related to the overall safety of the chassis system. With the advancement of material technology, the material of the automobile control arm has been changing. This article analyzes the trend of material selection for automobile control arms and finds the future direction of control arm material selection through the specific application data of the vehicle model, which can provide a reference for the selected research of automobile control arms
Optimization of stretch film former of fresh food packaging machine
Authors: Zhang Chao , Xu Na , Zheng Zhaoqi 
Published: December 2022

Abstract
Current research on fresh food packaging machines focuses on vertical and horizontal sealing. Compared with the conventional pillow packaging machine, the fresh food packaging machine still presents deficiencies regarding the feeding and forming ability of stretch film. This paper presents a step former for the stretch film to integrate the existing forming mechanism. First, by analyzing the movement diagram of the stretch film on the support plate, the optimal inclination angle of the stretch film during the process of feeding on the upper part of the support plate, and the center position of the second directional wheel on the upper part of the support plate was found, it can ensure that the stretch film in the process of feeding and forming has the minimum tension and not be broken. In addition, based on the above-mentioned, the support plate and the directional wheel were simulated in software. The 2 mm 304 stainless steel support plate and different plastic combinations of directional wheels were the optimal choices.