bluuebunny/crossref_metadata_2025_split huggingface dataset:
Self-gravity Simulation Method Based on Distance-controlled Mesh Encryption
Authors: Lin Zhiyong , Qiang Li’e , Zhao Shuhong 
Published: March 2023

Abstract
In the space-borne gravitational wave (GW) detection mission, the self-gravity noise caused by the deformation and residual jitter of the satellite platform is an important source of the total acceleration noise. In order to estimate the magnitude of the noise, the gravity acceleration and gravity gradient at the TM need to be carefully evaluated, which requires high accuracy of the self-gravity simulation. After the satellite component is divided into several mass cells by using the grid generation technology, if the number of cells is too small, the total gravity and gravity gradient obtained by superimposing the gravity between each cell and the TM will deviate greatly from the true value. On the other hand, directly densifying all single cells will produce a large number of new cells, reducing the simulation efficiency. Aiming at these problems, we present here the self-gravity simulation method based on distance-controlled grid refinement, analysis of subdivision unit size, unit and the distance between the test quality and the relationship between the simulation error, select the appropriate scaling factor to encrypt the initial mesh. It is expected to reduce the number of units on the premise of meeting the precision requirements of self-gravity simulation and then improve the simulation efficiency. The model test shows that when the grid cells are hexahedral, compared with simulation results using uniformly mesh encryption, the accuracy of the self-gravity simulation results based on distance-controlled is an order of magnitude higher, and the total number of grid cells used is less.
Model Predictive Control of Aerodynamic Heat Simulation Heating System with Discrete-time Linear Extended State Observer
Authors: Bai Zhiqing , Zhang Guangming , Wang Gang , Deng Ke , Lv Xiaodong 
Published: March 2023

Abstract
In this paper, a novel Model Predictive Control (MPC) scheme based on discrete-time Linear Extended State Observer (LESO) is proposed for the Aerodynamic Heat Simulation Heating System (AHSHV). First of all, the mathematical model and the predictive model of AHSHV are established, while the unknown terms of the predictive model can be observed by discrete-time LESO. Next, the cost function is constructed for rolling optimization control, and the rolling optimization replaces global optimization with local optimization. Each local optimal control is a feedback correction, and the combination of rolling optimization and feedback correction ensures the performance of the control system. Finally, the simulations and comparison results verify that the MPC scheme proposed in this paper performs better than the traditional PID control scheme in terms of static characteristics, dynamic characteristics, and robustness.
FPGA-Based Time-to-Digital Converter for Pulsed Laser Ranging
Authors: Wu Qishen , Zhang Yan 
Published: March 2023

Abstract
This paper implements a Time-to-digital Converter (TDC) in a field-programmable gate array (FPGA), which is made for a single-photon-counting-based pulsed laser ranging system. The fine time is measured by the Tapped Delay Line (TDL) constructed in an internal dedicated carry chain of the FPGA. The length of the TDC is longer than one clock period, and the whole CARRY4 is utilized as a delay unit. The proposed TDC is made up of the fine time measurement module, encoder, coarse time counter, and data transport module, which are achieved in a resource-tensed FPGA Xilinx-ZYNQ. As this paper is done in a shared FPGA, the presented TDC can replace the ASIC-TDC GP22 as the TOF measurement module. By measuring the same time interval and modifying the fixed error in TDC, the results show that the time resolution can reach 53 ps. Compared with the ASIC-TDC GP22, both linearity and measurement range are improved in the proposed TDC, which makes the pulsed laser ranging system more flexible and integrated.
Influence of Characteristic Parameter on Extrusion Stress with Working Surface of the Zigzag-shroud Blade
Authors: Li Shifeng , Zhang Jianqiang , Chen Suling 
Published: March 2023

Abstract
Taking a high aspect ratio and low-pressure turbine blade as an example, the research on the influence of zigzag-shroud characteristic parameters on the circumferential tightness and extrusion stress of the working surface, the comprehensive influence law of the zigzag-shroud key parameters on blades strength can be obtained to reduce the zigzag-shroud stress level to the allowable range. It is found that the engagement angle (β) and pre-torsion angle (△β) are the two key parameters to determine the tightness of the contact surface. When the engagement angle is 40.9°, the extrusion strength of the zigzag-shroud working surface is the highest. At the same time, it is found that the pre-torsion angle and circumferential degree (△S) are proportional to the extrusion stress of the working surface, and there is an “optimal window” for both circumferential degree and pre-torsion angle. The best circumferential degree is 0.22 mm, and the optimal pre-torsion angle range is from 30’ to 1° by the calculation model.
Multi-airport System Route Network Optimization Based on Differentiated Positioning
Authors: Wang Xueyao , Guo Xin 
Published: March 2023

Abstract
Air routes in China’s existing multi-airport system are unreasonable and homogeneous, leading to a significant gap in utilization between different airports and a waste of airport resources. One differentiated positioning model is proposed to optimize the air route network to solve the above problems. Balanced development of airports and passenger costs are considered in the model. Finally, the model is validated using the 2019 route network dataset in the Beijing-Tianjin-Hebei multi-airport system (BTH MAS). The optimization results for the multi-airport system show an average increase of 15% in airports utilization, an average increase of 6% in the differentiated realization rate, an 8% reduction in the average cost of passenger travel fees, and a 17% reduction in route repetition with no reduction in the number of connections to destination airports.
Research Progress in Numerical Simulation of Aircraft Wing Flow Field
Authors: Ma Zongren , Tang Zhengyang , Wang Ruixuan , Yu Zhuoyuan 
Published: March 2023

Abstract
Computational fluid dynamics has important application value and theoretical significance in engineering. Fluid mechanics has emerged as a way out of many engineering design problems. In recent years, applying fluid mechanics in the aircraft field has brought a breakthrough to problems that could not be solved previously. This paper mainly introduces the development history of the application of computational fluid dynamics in the direction of the wing and the specific application of this technology in the numerical simulation of the wing flow field. The aerodynamic characteristics of aircraft wings are related to the flight performance of the aircraft. The influence of wing aerodynamic characteristics, wing lift drag coefficient, and wing noise is a hot research issue. The influence of flow field research methods (such as numerical simulation) on the optimization and improvement process of the wing is analyzed, and the numerical results and simulation results of the flow field are found. The future development trend of the wing is proposed. Finally, it is believed that changes in airfoils will have a significant impact on aircraft performance.
Spatial and Temporal Distribution of Near-Surface Methane Concentration in Northwest China Based on GOSAT Satellite Data
Authors: Lian Haotian , Shi Xiaoqi , Shen Yufei , Wang Chuyu 
Published: March 2023

Abstract
Methane (CH4) is a common greenhouse gas that plays an important role in global warming and affects people’s production and life. In order to study the temporal and spatial distribution situation of methane concentration in northwest China (Shaanxi, Gansu, Ningxia, Xinjiang, Qinghai), this article used L4B level data products monitored by GOSAT satellite from 2009 to 2019 to study the temporal and spatial distribution characteristics of near-surface methane concentration in northwest China. The results of the analysis were as follows. Firstly, the annual average concentration of near-surface methane in northwest China was in a rising state, and the maximum annual average concentration increment was in 2016. Secondly, seasonal variation of methane concentration: Autumn>Summer>Spring>Winter. Finally, spatial variation of the annual average methane concentration: Shaanxi, Ningxia, and southern Gansu>northwest Xinjiang>other northwest China regions. The methane concentration decreased from the bottom to the top gradually.
Ultra Short-term Load Optimal Dispatching Method for Micro Grid Considering Demand Side Response
Authors: Zhu Tao , Yang Kang , Li Lanqing , Cui Zhanfei , Lu Qiuyun 
Published: March 2023

Abstract
With the development of the economy, the electricity demand is also increasing. However, the traditional micropower supply bears the problems of excessive load growth and unstable voltage. Therefore, this paper takes power generation as the research object. First, the principle of output optimization based on schedulability, reserve capacity, and intermittent operation frequency of units is analyzed. Then, the relationship between the optimal solution and the minimum power consumption time is calculated by establishing a mathematical model to solve the algorithm, and the difference between the two results is compared. Finally, the power system is simulated on Matlab software, and the method and effect are verified by numerical simulation. The simulation results show that with the same microgrid power configuration, there is a 3.5% load transfer at time-sharing prices and a 6.4% load transfer at real-time prices through price-based demand response. The optimization objective of demand response, namely the cumulative sum of the difference between new energy power generation and load, is 15312 kW · h per year when the fixed price is implemented, 54134 kW · h is for the time of use price, and 451645 kW · h is for real-time price. The response effect of real-time price is optimal.
Vibro-acoustics time domain FEM-BEM analysis of a Titian Stradivari violin: the role of the bridge
Authors: Kaselouris Evaggelos , Dimitriou Vasilis 
Published: March 2023

Abstract
The acoustic behaviour of the violin is defined during manufacturing since the vibrational acoustic properties of the instrument are related to the top plate’s vibrational modes in a direct way. An important component of the violin assembly is the bridge. The bridge transfers the excitation forces from the strings to the soundboard via the bridge feet and acts as a sound filter. In this study the Titian Stradivari violin CAD geometry of the soundboard, including the f-holes and bass bar, and the bridge is modelled, and time domain coupled finite element method-boundary element method, vibro-acoustic, simulations are performed to analyse the interference of the instrument’s sound with its structural components. A comparison of the vibroacoustic behaviour for the soundboard with and without the bridge enlightens the crucial role of the bridge. This initial computational approach will be extended, with similar studies on the role of every structural component of the violin individually, aiming to decode the full violin soundbox vibroacoustic behaviour and provide key insights for violinmakers on how structural changes affect the quality of the emitted sound.
Technologies and Applications of Pipeline-type Oil-gas-water Separation
Authors: Zhang Jun , Su Lide , Han Jipu , Sa Qier , Wang Juntao , Chai Weichen , Li Bingyu , Zhong Xingfu 
Published: March 2023

Abstract
The separation of oil, gas, and water mixture is an important process in the production of crude oil. Traditional separation tanks are large, heavy, long in separation time, and high cost to manufacture. This paper introduces a separation technology with the main characteristics of the pipeline structure. This technology uses the principles of centrifugation, expansion, air flotation, and gravity separation. Pipes and other equipment are the core equipment, which has the advantages of flexible process composition, small footprint, and high separation efficiency. This technology can be used for rapid oil, gas, and water separation, solving the problems of expansion, upgrading old oilfield stations, realizing the purpose of re-injection of water in-situ, energy saving, and reducing emissions.
Analysis of Aircraft Parking Stability Based on Atmosphere Boundary Theory
Authors: Liu J , Ge J L , Yang H , Chen W S , Wu J H , Qu Q L 
Published: March 2023

Abstract
Based on numerical simulation technology, the aerodynamic load research of civil aircraft parked on the ground is conducted. The CRM model parked on the ground is established by CFD software. Based on the atmospheric boundary layer theory, the seven incoming flow conditions for numerical calculation are designed. And the aerodynamic loads’ change of the aircraft model is calculated when the -90° sideslip angle. The result shows that the mooring load on the nose landing gear mainly comes from the longitudinal load caused by the upwards pitching moment on the flat tail and the lateral load caused by the yaw moment; since the rolling moment coefficient is less than the pitching moment coefficient by two orders of magnitude, which hardly affects the mooring load. The study provides a reference for reducing the mooring load of civil aircraft under heavy wind conditions.
Structure design of a radar display console muffler
Authors: Kang Ji , Zhang Liang Juan , Liu Sheng Sheng , Lv Zhao Hui 
Published: March 2023

Abstract
Radar display console is an equipment which is closely associated with people as a medium of human-computer interaction. However, for the sake of heat dissipation, draught fans in display console make continuous noise when radar is on operation, the noise dose harm to human health. In order to reduce the noise, an impedance compound muffler is designed in this paper, and then the acoustic characteristics of muffler is studied by simulation method. In the end, the simulation results are verified by means of noise spectrum analyser, as a result, the muffler obtains good silencing effect and the maximum sound level of the radar display console is reduced by 3dB.
Underwater source localization based on a matrix distance measurement
Authors: Guo Yuyan , Gong Xianyi 
Published: March 2023

Abstract
In this paper, a matrix distance measurement is introduced to underwater source localization. Matched field processing (MFP) and beamforming(BF) are widely used methods that both make the correlation between data and copy vectors. We proposed statistical matched field processing (SMFP) and statistical beamforming (SBF) in this paper that measure the distance between data and copy cross-spectral density matrices (CSDMs) in place of the correlation of the two vectors. As CSDM is Hermitian and positive semidefinite, Riemann distance is suitable. Matrix-matrix comparison increases the dimension of the system compared with vector-vector correlation, so as to include environmental uncertainty. SMFP and SBF are compared with conventional matched field processing (CMFP) and conventional beamforming (CBF) respectively in simulations. The results show that SMFP and SBF achieve satisfactory localization performances.
Numerical investigation of submerged impinging jet based on different turbulent models
Authors: Ge Jie , Wang Chuan , Yao Yulong , Chen Xinxin 
Published: March 2023

Abstract
In today’s world, the loss of effective storage capacity caused by reservoir siltation has reached 50 billion cubic meters per year. As a high impact and simple water jet technology, submerged jet impact can have a powerful washout effect on submerged sediment. On this article, the submerged impinging jet is numerically computed with importing the Wray–Agarwal (W-A) turbulence models in FLUENT. Then, the streaming field analysis of the jet under different conditions is carried out and compared to the PIV test outcomes. To validate the effectiveness of the W-A turbulence models for predicting the streaming field of submerged impinging jet. The results show that, relative to other turbulence models, the calculated findings of the Wray–Agarwal turbulence model are in much closer accordance with the test data.
Study on the relationship between intercalation rate of melt-blown nonwovens and process parameters based on correlatio n analysis
Authors: Guo Hongze , Gao Ke , Liu Yingchang , Yu Yue 
Published: March 2023

Abstract
The melt-blown nonwoven material is an important raw material for mask production, which has attracted much attention. There are many technological parameters for the preparation of intercalated melt-blown nonwovens, and there are interactive effects among the parameters, which are more complicated after intercalation airflow. In order to better study the regulation mechanism of product performance, our team established a mathematical model of process parameters with structural variables and a mathematical model of structural variables with product performance based on 25 groups of control experiments and experimental data of fixed intercalation rate. Also, we tried to solve different problems with the models. Based on correlation analysis and partial correlation analysis, the preparation process parameters of intercalated melt-blown nonwovens are explored to some extent, and the influence of intercalation rate is analyzed, which provides a relatively reliable theoretical basis for industrial production.
Design of TaCu alloy coating for orthopaedic materials and study on dissolution behavior of copper ions
Authors: Yu Xiaoming , Guo Zhaoxin , Yi Haowei 
Published: March 2023

Abstract
In this study, tantalum copper (TaCu) alloy coating was designed and fabricated by the chemical vapor deposition (CVD) method, while the process was explored through COMSOL Multiphysics software. The influence of deposition temperature on coating quality was studied in combination with our previous work. In addition, the galvanic corrosion behavior of TaCu coating in Hank’s solution was simulated through this software. The COMSOL Multiphysical software can be used to simulate the process that TaCu coated on the surface of titanium(Ti) alloy substrate by chemical vapor deposition. The deposition quality was affected by the direction of the deposition airflow. Cu ion dissolution makes the coating thickness decrease uniformly, Cu ion dissolution accelerates due to galvanic corrosion, and the antibacterial ability of the coating can be improved due to Cu ion dissolution.
Adsorption and diffusion of sodium on boron-doped carbon nanotube
Authors: Fan Kaimin , Ni Jiangfeng , Tang Jing , Ding Ruiqiang , Zhu Hongwei 
Published: March 2023

Abstract
The first principles have been performed to investigated the performance of the boron-doped (B-doped) carbon nanotube for sodium-ion batteries. The Na adsorption energies at H1 and B1 sites are -2.821 eV and -2.523 eV, which have decreased by 0.985 and 0.846 eV as compared with pure CNT, respectively. The results indicate that B-doped CNT is beneficial for Na adsorption. The Na diffusing between two hollow sites across the TC1 and B1 sites shows low barriers of 0.309 eV. Additionally, the projected density of states (PDOS) shows that B-doped CNT exhibits metallicity and non-magnetic properties with Na adsorption, which is beneficial for electron transfer. The PDOS move towards higher energy levels, which is beneficial to enhance conductivity. These results suggest that B-doped CNT shows high performance as anode for sodium-ion batteries.
The Novel Nanoscale Compound and its Suppressing Lattice Thermal Conductivity in Cu-Ni-Sn-S systems
Authors: Liu Shuqiang , Zhang Yingjie , Li Enliang , Li Chao 
Published: March 2023

Abstract
The microstructure research of eco-friendly thermoelectric material is key to optimizing thermoelectrical properties. The microstructures of Cu2Ni0.1Sn0.9S3 ceramic with low thermal conductivity were studied using X-Ray diffraction, transmission electron microscopy and X-ray energy dispersive spectroscopy. The cubic metastable Cu26-x
Ni4+x
Sn4S32 nanoprecipitates embedded in the matrix were observed. This metastable nanoprecipitate shows certain orientation relationships with the matrixs and unclear interface area. Finally, the occupation semiorder of Cu atoms in Cu26-x
Ni4+x
Sn4S32 nanoprecipitates, coherent heterointerfaces between Cu26-x
Ni4+x
Sn4S32 and matrix can scattered phonon of similar wavelength to suppress lattice thermal conductivity.
Liquid Concentration Measurement Based on Liquid Contact Angle
Authors: Wang Xiahui , Ye Wenjie , Chen Xiye , Chen Qinghua , Xu Guowang , Liu Yukuai 
Published: March 2023

Abstract
Different concentrations of the same liquid or liquids with different solutes have different surface tensions. The macroscopic phenomenon is that they have different wetting effects on the same solid surface. The liquid contact angle can describe the wetting effect. Therefore, this paper proposes a method for measuring the liquid concentration using the liquid contact angle. A glass plate with a hydrophobic layer and an angle-measuring device forms the detection part. The glass plate is placed horizontally, and the solution to be tested is dropped on the surface of the glass plate. Solutions with different concentrations have different liquid-solid interfacial tension and liquid-gas interfacial tension, resulting in different liquid contact angles, which can achieve rapid and accurate measurement of solution concentration. Experiments show that the liquid contact angle of ethanol solution decreases with the increase of liquid concentration. Different volumes of ethanol solutions with the same concentration have substantially the same liquid contact angle. This experimental method has the advantages of being simple and easy to operate, having a wide range of applications, not easily limited by the type of detection solution, having a large concentration measurement range, having less sample usage, free from electromagnetic interference, and having real-time online detection.
Simulations of Magnetic Field Variations Around Rectangular Defects of Ferromagnetic Materials
Authors: Jorge Montes de Oca‑Mora Natanael , María Woo‑Garcia Rosa , Elizabeth Vázquez-Valdes Suany , Leobardo Herrera‑May Agustín , Sánchez Adrián , Arturo Cerón‑Álvarez Carlos , Restrepo Johans , Algredo‑Badillo Ignacio , Lopez‑Huerta Francisco 
Published: March 2023

Abstract
The ferromagnetic structures require techniques of defects inspection for their structural monitoring. The early detection of these defects can prevent structural failures that cause economic losses and environment damages. Herein, we present a model for numerical simulations of the magnetic field variations around rectangular defects in ferromagnetic materials by Python programming language. These simulations can predict the behavior of the magnetic field variation caused by rectangular defects considering the study of the magnetic domains of the ferromagnetic material. The numerical simulations of magnetic field around three rectangular defects with different depths (1, 3, and 5 mm) and the same width of 3 mm are studied. The results of the numerical simulations agree well with the behavior of cracks. The proposed model can be used to estimate potential structural failures in ferromagnetic structures.