bluuebunny/crossref_metadata_2025_split huggingface dataset:
Capacity assessment of railway axle journal bearing addressing a localized rolling contact fatigue failure mechanism
Authors: Xin Min , Bian Zhi-Hong , Zhao Yong-Xiang 
Published: July 2024

Abstract
A framework for assessing the capacity of railway axle journal bearings is presented after elaborating on the locale rolling contact fatigue (RCF) failure mechanism. Three phases are conducted, including the determination of bearing service loads, finite element analysis (FEA) on the localized RCF stresses of bearing components, and the life-related capacity assessment on the bearings and bearing components. Results prove that wheel-track (WT) contact forces inspected by an instrumented wheel set can be transferred into bearing service loads. Two-step FEA from the global wheel set to the local bearings is used to obtain localized RCF stresses at dangerous locations around the bearing contact regions. After determining the locations, a life-related capacity assessment is performed by evaluating equivalent RCF stresses and lives at the locations to determine the weakest bearing component. Typical practice is given in agreement with FEA. This method deals with the FEA of bearing structures, material cyclic stress-strain curves, and probabilistic RCF life curves. Therefore, this work greatly enhances the development of rail-bearing materials, innovative structures, and capacity assessment.
Study on primary frequency modulation control strategy based on wind-fire cooperation
Authors: Li Kai 
Published: July 2024

Abstract
Due to the increasing proportion of wind power in the power system, the wind turbine should have the ability of primary frequency modulation when integrated into the power system. At the wind turbine level, different methods are adopted according to different wind speeds, which can get the wind turbine fully joined in the system. Secondly, this paper gives full consideration to the characteristics of thermal and wind power units and proposes a joint primary frequency modulation method between the thermal and wind farms. The output of wind and thermal power is determined by adding a frequency divider. The system stability and reaction speed are effectively enhanced.
Design and Simulation Analysis of Antenna Structure for Active Phased Array Radar
Authors: Cai Sen , Yang Zhen , Li Jingxiao , Lu Dongdong , Shi Tongwu 
Published: July 2024

Abstract
This article adopts a modular design concept to design an active phased array radar antenna system structure and elaborates on its structural layout design and thermal design content. A finite element model of the antenna structure framework was established, and the rationality of its structural and thermal design was verified through static and thermal simulation analysis.
Simulation and Experimental Correction of Thermal Errors in Electric Spindles
Authors: Zhang Yu , Zhang Qiangang 
Published: July 2024

Abstract
The heat generated by the spindle leads to thermal deformation, which can seriously affect machining accuracy. ANSYS software is used to establish the heat-fluid-solid coupling simulation model of the electric spindle. Temperature rise and thermal error experiments of the electric spindle are carried out. We modified the theoretical and empirical values used in the simulation according to the experimental data. Experimentally, it is demonstrated that the precision of the simulation increased by 27% after modification.
Identification Method of Transmission Line Parameters Considering Impact of Electro Thermal Coupling Effect
Authors: Wu Yifan , Dong Xiaoming , Yu Shunxiang , Fan Jingdong 
Published: July 2024

Abstract
Studies for high voltage power networks generally ignore line resistance with the assumption of being far less than line reactance. However, this treatment could cause certain errors in analysing low-voltage distributed networks, causing the assumption to no longer be applicable. Such errors could be significant considering the impact of load carrying and ambient conditions, such as online resistance or temperature due to electro-thermal coupling (ETC). Then, it becomes an open question to accurately capture the system state of distribution networks due to changed line parameters. Integrating new style energy sources, such as renewable power generation, energy storage applications, and adjustable power load, will promote the deployment of measurement devices at distribution networks. With the assumption of sufficient accumulated data offered by online monitoring terminals, this study proposes a nonlinear regression method—Levenberg-Marquardt—to identify the parameters of the line. However, since it is difficult to access practical data, this study employs the electro-thermal coupling power flow (ETCPF) to simulate line operation and take the results as monitoring data for case studies. The identification results under various data volumes and error levels demonstrate the reliability and accuracy of the proposed approach.
Adaptability Analysis of Differential Protection for Output Transformers in Wind Power Plants
Authors: Yang Xuemei , Li Hanjiang , Ni Yingqian , Deng Bowen , Ren Tingting 
Published: July 2024

Abstract
After large-scale integration of wind farms into the power grid, according to the requirements of the State Grid’s wind power grid connection operation guidelines, wind farms should have low-voltage ride-through capability. The short-circuit current of wind farms will have a significant impact on the identification of excitation inrush currents in the transformers sent out by the wind farms, and the saturation of current transformers will also have an impact on differential protection. Analysis shows that after the wind power is connected, the harmonic components contained in the fault current output by the wind farm will cause the second harmonic braking component to malfunction, and there is a risk of transformer differential protection rejecting operation. At the same time, it will make the current transformer more susceptible to saturation, and the saturation of TA will increase the differential current of the transformer, which may cause misoperation of the transformer differential protection.
Multi-Objective Optimization Design of 40 MW High-Temperature Superconducting Motor
Authors: Jia Shiqi , Zhang Dong , Wang Lei , Zhang Jiancheng , Zhang Guomin 
Published: July 2024

Abstract
To reduce the length of the superconducting wire of the superconducting motor, the no-load back EMF E and the magnetic field component perpendicular to the wire B⊥ were selected as the optimization goals. Therefore, a multi-objective optimization method based on the Response Surface Method (RSM) and Genetic Algorithm (GA) was proposed by taking a high-temperature superconducting motor (HTSM) with a rated power of 40 MW as the research object. Firstly, the overall structure, mathematical model, and output characteristics of HTSM were introduced. Secondly, the sample points required for constructing the RSM equation were obtained by Finite Element Analysis (FEA), and the multi-objective optimization of the RSM equations was performed by applying GA to obtain the Pareto optimal frontier. Finally, the calculated optimal design was simulated and verified. Compared with the initial design, the E of the optimized HTSM was increased by 4.47%, and the B⊥ was reduced by 4.83%. Based on the motor parameters obtained by multi-objective optimization, the final optimized design of HTSM was obtained. The length of the superconducting wire used in the motor has been reduced by 10.2%, which greatly reduces the cost.
Model-free three-vector predictive current control of permanent magnet synchronous motor based on improved sliding mode observer
Authors: Huang Nan , Zhang Yufeng , Tian Beibei 
Published: July 2024

Abstract
To address the complexity of vector selection in the conventional predictive current control strategy and the reduction of control system robustness when the motor parameters change, this paper proposes a finite-set model-free three-vector predictive current control method for permanent magnet synchronous motor based on the improved sliding-mode perturbation observer. According to the mathematical model of a permanent magnet synchronous motor under perturbation, a new hyperlocal model is established, and the conventional vector traversal optimization method is optimized to obtain the necessary basic voltage vector by analyzing the function with one judgment. Meanwhile, the sliding mode perturbation observer is designed using the fast exponential convergence law to observe the unknown part. Finally, by experimentally contrasting the proposed technique with the conventional three-vector model predictive current control, the method suggested in this paper can successfully reduce the current pulsation and inhibit the system perturbation caused by the parameter change, ensuring the steady state performance of the motor, as demonstrated by the experimental comparison with the conventional three-vector model predictive current control method.
Influence Law of Electromagnetic Induction Heating Parameters on the Leveling Effect in Thin Plates
Authors: Wang Yefan , Li Shengrong , He Zixi 
Published: July 2024

Abstract
In order to analyze the influence of electromagnetic induction heating parameters on the leveling effect of thin plates after welding, and summarize their influence rules, this paper first introduces the principle of induction heating, further reveals the mechanism of electromagnetic induction heating to control the deformation of thin plates, and discusses the parameters that affect the process of electromagnetic induction heating. Based on this, the electromagnetic induction heating under different gap distances, current intensity, and heating frequency is simulated by finite element simulation software. The experimental verification is carried out, which lays the foundation for selecting the appropriate electromagnetic induction heating-related parameters.
Analysis and Modeling Study on the Effect of Working Parameters of Portable Neutron Tubes on Target Current
Authors: Li Zhuoxi , Guo Wei , Chen Yiting , Xu Pengcheng , Liu Guocai 
Published: July 2024

Abstract
As an important parameter index of sealed neutron tubes, their high-pressure side target current directly affects neutron yield. The working parameters of a neutron tube affect the target current. Using self-developed neutron tubes, the influence of operating parameters of neutron tubes on target current was studied. The effect curves of gas pressure, anode high pressure, and target high pressure on neutron yield were obtained, and the secondary electron suppression characteristics of the target current were obtained. Further, we analyze and fit a multi-parameter coupling model for the target current, to provide a theoretical basis for establishing the working state and improving the performance of sealed neutron tubes.
Direct Writing Highly Conductive Silver Pattern on Flexible Substrate Based on Particle-Free and Ionic Liquid-Assisted Ink
Authors: Xie Xiaosheng , Wu Zijian , Pan Daocheng , Shi Xinan 
Published: July 2024

Abstract
Particle-free silver inks have the advantage of low sintering temperature, high stability, and easy synthesis over traditional nanoparticle-based silver inks, which have been widely applied in the printing electronic industry. In this paper, we develop a novel particle-free and ionic liquid-assisted silver ink consisting of silver acetate and formic acid/iso-propanolamine liquid that can be used to print highly conductive silver patterns at low sintering temperatures. A variety of continuous and consistent silver circuits with a resistivity of 7.7 µΩ·cm can be printed by a dispenser machine, which is only 4.8 times bulk silver. Furthermore, the low-resistivity silver patterns can be also printed on the flexible polyimide foil, which maintains the stability of resistivity and mechanical properties after bending multiple times, demonstrating that our ionic liquid-assisted silver ink can be applied in flexible electronic devices. Besides, our particle-free silver ink can be utilized to write electric circuits directly with a ball-point pen.
2 μm Low-noise Narrow-linewidth Single-frequency Fiber Laser Based on Self-injection Locking Technique
Authors: Gao Ruixiang , Fang Qiang , Xu Yang , Gao Song , Jiang Peiheng , Fu Shijie , Sheng Quan , Shi Wei 
Published: July 2024

Abstract
Based on the self-injection locking technique, we demonstrate a low-noise and narrow linewidth of 2 μm single-frequency distributed Bragg reflection fiber laser with an optical self-injection feedback loop (OSIFL). The OSIFL consists of a piece of delay fiber and two polarization-maintaining optical couplers, which can effectively narrow down the linewidth and suppress the relative intensity noise (RIN) of the laser. It was observed that the laser linewidth was narrowed down from the initial 6.5 kHz to 1.6 kHz while the laser relaxation oscillation peak was reduced from -100.3 dB/Hz to -113.5 dB/Hz. Experimental results demonstrate that by extending the photon lifetime we can effectively narrow down the linewidth and significantly reduce the RIN of the laser. This research is of great significance for promoting the development and application of 2 μm single-frequency lasers.
Ground Fault Routing Method for Flexible Grounding System Based on Transient Zero Sequence Current Comparison
Authors: Liu Cuicui , Wang Xiaoshuai , Xue Yongduan 
Published: July 2024

Abstract
As a new development direction of the domestic medium voltage distribution network, the flexible grounding method has a rapid expansion trend, and accordingly, the ground fault protection scheme needs to follow up quickly. This paper calculates and analyzes the distribution characteristics of transient electric quantities in the system under different fault conditions by establishing the transient equivalent model of shunt small resistor casting and cutting in the flexible grounding system. It is found that if transition resistance is small, the application of parallel small resistors will cause the transient zero sequence current amplitude of the faulty line to be maximum and have opposite polarity to the healthy line. When transition resistance is high, distribution characteristics of the transient zero sequence current projection component are also the same. Based on the above features, a flexible grounding system ground fault routing method is proposed, which can cope with a variety of ground fault situations in engineering practice with high reliability, and the correctness of the method is verified through simulation.
Analysis of Influence of Different Running Speeds on Lubrication Performance of Plain Bearings
Authors: Zhang Guangming , Shen Jifei , Zhu Hongxiu , Xiao Run 
Published: July 2024

Abstract
Given the influence of the running speed of rotating machinery on the lubrication performance of sliding bearings, based on the hydrodynamic lubrication theory, a numerical analysis model of hydrodynamic lubrication of rolling bearings is established and solved by the finite difference method. The lubrication characteristics of rolling bearings, such as oil film pressure, oil film temperature, oil film thickness, and temperature rise at different running speeds (10 r/min, 30 r/min, 120 r/min, 160 r/min), are obtained. The results show that the sliding bearing shows different trends at different rotational speeds, the maximum oil film temperature is 70.49℃, the film thickness ratio corresponding to the minimum oil film thickness is much more than 3, and the maximum oil film pressure and temperature rise meet the allowable requirements.
Simulation and Experimental Study of Mooring Function Composite Fragile Cover
Authors: Mao Yafei , Yu Jingui , Zhang Qiaoxin 
Published: July 2024

Abstract
Under the requirement that the fragile cover does not eject debris during missile launches, and to meet the demands of rapid combat, there is an urgent need for a lightweight missile launching system. Enhancing the effective utilization area of the fragile cover is an effective way to realize the lightweight of the missile launching system. This paper utilizes the properties of carbon fiber composite materials to design a novel frangible cover with mooring functionality and establishes numerical models for the cover’s pressure and bursting dynamics. In the pressure finite element model, the Tasi-Wu failure criterion is employed for damage assessment. In the bursting dynamics finite element model, a cohesive element is used to simulate the elastic behavior and damage evolution of the weak area, while a membrane element is employed to simulate the mooring function. Comparative analysis of numerical results with experimental data reveals minor discrepancies, with errors of 5.44% for maximum deformation under pressure and 8.1% for bursting force, respectively, validating the model’s rationality and effectiveness. Results from both experimental tests and finite element analyses demonstrate the successful implementation of mooring functionality in the segmented body. The effective utilization area of the cover was increased by 71.13%. This research provides a feasible direction for subsequent studies on non-ejecting frangible covers.
Evaluation Method of Generatrix Straightness Coefficient and Application in AZ31 Magnesium Alloy Panel
Authors: Li Yanjuan , Wang Zhongtang , Liu Quan 
Published: July 2024

Abstract
An evaluation method of the generatrix straightness coefficient for magnesium alloy panel is proposed. The generatrix straightness coefficient and characterization parameter are defined. The reasonable process parameters for equal curvature grid panels were determined, and various specifications of magnesium alloy grid panels were processed. For the magnesium alloy grid panel, with an increase in the curvature radius of the panel, the deviation of generatrix straightness and generatrix straightness coefficient of each point is reduced. The deviation of generatrix straightness at the junction of the transverse is the smallest. The deviation of generatrix straightness at the center of the grid is the maximum. The deviation of generatrix straightness at the junction of transverse and longitudinal ribs was minimal. The maximum deviation of generatrix straightness is 0.097 mm, and the maximum generatrix straightness coefficient is 0.277%.
Comprehensive Evaluation Study of Innovative Measurement Techniques in Surface Roughness within Manufacturing Processes
Authors: Guo Zizhou , Li Shuncai , Wang Xin 
Published: July 2024

Abstract
With the advancement of modern technology, numerous advanced methods for measuring surface roughness have emerged. These are categorized into contact and non-contact methods, such as optical, ultrasonic, and machine vision measurements. By researching and integrating various characteristics, including cutting parameters, vibration, and force signals, with workpiece texture images, a comprehensive model for predicting surface roughness is formed. These novel multidimensional feature prediction equations significantly enhance practicality and accuracy in assessing the surface quality of machined workpieces, marking a clear advancement over traditional measurement techniques.
Analysis of Novel Materials for Active Homogeneous Fields in High-field Nuclear Magnetic Resonance
Authors: Yan Ming , Wang Yaohui , Wang Heyang , Wu Pengfei 
Published: July 2024

Abstract
Nuclear magnetic resonance (NMR) spectroscopy, based on its extremely high backfield, can be used for the imaging and analysis of matter, which has given mankind a clearer perception of the composition of matter. The homogeneity of the magnet is the key to imaging. This paper analyzes the characteristics of various novel materials with active homogeneous fields regarding critical temperature, critical magnetic field, critical current and stress structure. The results show that YBCO and Bi-2223 strip structures cannot be wound when making coils, and with the change of rotation angle, the stronger the electromagnetic force on the strip, the greater the strain, which makes it difficult to fabricate uniform-field coils with high precision. In contrast, the feasibility of Bi-2212 in superconducting uniform-field coils is basically satisfied, and it has better performance.
An exactly solvable asymmetric K-exclusion process
Authors: Ayyer Arvind , Misra Samarth 
Published: July 2024

Abstract
We study an interacting particle process on a finite ring with L sites with at most K particles per site, in which particles hop to nearest neighbors with rates given in terms of t-deformed integers and asymmetry parameter q, where t > 0 and

q
⩾
0

are parameters. This model, which we call the (q, t) asymmetric simple K-exclusion process (ASEP), reduces to the usual ASEP on the ring when K = 1 and to a model studied by Schütz and Sandow (Phys. Rev. E, 1994) when

t
=
q
=
1

. This is a special case of the misanthrope process and as a consequence, the steady state does not depend on q and is of product form, generalizing the same phenomena for the ASEP. What is interesting here is the steady state weights are given by explicit formulas involving t-binomial coefficients, and are palindromic polynomials in t. Interestingly, although the (q, t) K-ASEP does not satisfy particle-hole symmetry, its steady state does. We analyze the density and calculate the most probable number of particles at a site in the steady state in various regimes of t. Lastly, we construct a two-dimensional exclusion process on a discrete cylinder with height K and circumference L which projects to the (q, t) K-ASEP and whose steady state distribution is also of product form. We believe this model will serve as an illustrative example in constructing two-dimensional analogues of misanthrope processes.
Simulations are attached as ancillary files.
Root patterns and exact surface energy of the spin-1 Heisenberg model with generic open boundaries
Authors: Dong Jiasheng , Lu Pengcheng , Cao Junpeng , Yang Wen-Li , Marquette Ian , Zhang Yao-Zhong 
Published: July 2024

Abstract
We investigate the thermodynamic limit and exact surface energy of the isotropic spin-1 Heisenberg chain with integrable generic open boundary conditions by a novel Bethe ansatz method. We obtain the homogeneous (or two-term) Bethe ansatz like equations for the zero roots of the transfer matrix. Based on the patterns of the zero roots, we analytical calculate the densities of zero roots and the surface energies of the model in all regimes of the boundary parameters.