bluuebunny/crossref_metadata_2025_split huggingface dataset:
Increasing coverage of mono-layer graphene grown on hexagonal boron nitride
Authors: Jiang Chengxin , Chen Lingxiu , Wang Huishan , Chen Chen , Wang Xiujun , Kong Ziqiang , Wang Yibo , Wang Haomin , Xie Xiaoming 
Published: January 2023

Abstract
Graphene sitting on hexagonal boron nitride (h-BN) always exhibits excellent electrical properties. And the properties of graphene on h-BN are often dominated by its domain size and boundaries. Chemical vapor deposition (CVD) is a promising approach to achieve large size graphene crystal. However, the CVD growth of graphene on h-BN still faces challenges in increasing coverage of monolayer graphene because of a weak control on nucleation and vertical growth. Here, an auxiliary source strategy is adapted to increase the nucleation density of graphene on h-BN and synthesis continuous graphene films. It is found that both silicon carbide and organic polymer e.g. methyl methacrylate can assist the nucleation of graphene, and then increases the coverage of graphene on h-BN. By optimizing the growth temperature, vertical accumulation of graphitic materials can be greatly suppressed. This work provides an effective approach for preparing continuous graphene film on h-BN, and may bring a new sight for the growth of high quality graphene.
Transcranial ultrasound stimulation modulates the interhemispheric balance of excitability in human motor cortex
Authors: Ren Liyuan , Zhai Zhaolin , Xiang Qiong , Zhuo Kaiming , Zhang Suzhen , Zhang Yi , Jiao Xiong , Tong Shanbao , Liu Dengtang , Sun Junfeng 
Published: January 2023

Abstract

Background. Low-intensity transcranial ultrasound stimulation (TUS) could induce both immediate and long-lasting neuromodulatory effects in human brains. Interhemispheric imbalance at prefrontal or motor cortices generally associates with various cognitive decline in aging and mental disorders. However, whether TUS could modulate the interhemispheric balance of excitability in human brain remains unknown. Objective. This study aims to explore whether repetitive TUS (rTUS) intervention can modulate the interhemispheric balance of excitability between bilateral motor cortex (M1) in healthy subjects. Approach. Motor evoked potentials (MEPs) at bilateral M1 were measured at 15 min and 0 min before a 15 min active or sham rTUS intervention on left M1 and at 0 min, 15 min and 30 min after the intervention, and the Chinese version of brief neurocognitive test battery (C-BCT) was conducted before and after the intervention respectively. Cortical excitability was quantified by MEPs, and the long-lasting changes of MEP amplitude was used as an index of plasticity. Results. In the active rTUS group (n = 20), the ipsilateral MEP amplitude increased significantly compared with baselines and lasted for up to 30 min after intervention, while the contralateral MEP amplitude decreased lasting for 15 min, yielding increased laterality between bilateral MEPs. Furthermore, rTUS intervention induced changes in some C-BCT scores, and the changes of scores correlated with the changes of MEP amplitudes induced by rTUS intervention. The sham rTUS group (n = 20) showed no significant changes in MEPs and C-BCT scores. In addition, no participants reported any adverse effects during and after the rTUS intervention, and no obvious temperature increase appeared in skull or brain tissues in simulation. Significance. rTUS intervention modulated the plasticity of ipsilateral M1 and the interhemispheric balance of M1 excitability in human brain, and improved cognitive performance, suggesting a considerable potential of rTUS in clinical interventions.
Research on Direct Measurement to Spray Resistance Test of Prismatic Planing Hull
Authors: Shi Sheng-zhe , Jiang Ting , Wang Fan , Zheng Xiao-long 
Published: January 2023

Abstract
To obtain spray resistance directly, a prismatic planing hull test was conducted in a towing tank in static water. The characteristic angles of the standing line and leading edge line of the spray zone were obtained through the fixed flight test of the whole prismatic planing hull. The prismatic planing hull was divided into front and rear parts along the standing line, and then the fixed flight state test of the split planing hull was carried out, and the spray resistance was directly measured by the front planing hull. The results show that the percentage of splash resistance in the total resistance is from 15.83 % to 30.10 % under the condition of high-speed planing; Split planing hull model test is an effective method for direct measurement of spray resistance.
Finite element analysis of complete structure of tower cranes
Authors: Cheng Baozhong , Yang Bo , Wang Dianxi , Duan Mingyu 
Published: January 2023

Abstract
In order to ensure the safety and stability of the tower crane in operation, the static and dynamic characteristics of the QTZ100 tower crane in typical working conditions are analyzed by the finite element method, so as to verify the safety of its use and put forward targeted suggestions for the optimization of cranes. The results show that the equivalent stress is less than the ultimate design stress of the tower crane, and there is stress concentration in the plate connected between the upper turntable and the lifting arm. The frequency of the fully loaded motor is far from the normal operating frequency of the tower. The horizontal root displacement of the lifting arm corresponding to the peak displacement response is relatively large. The buckling factor of the tower crane is higher than the empirical value. Therefore, to meet the strength and stability requirements of the tower crane, the connection between the upper turntable and the lifting arm should be strengthened. The motor will not resonate with the tower crane when it is fully loaded, and the dynamic rigidity is poor when it works at the frequency corresponding to the peak value. The buckling factor is higher, so the stability is better.
Microstructure Evolution and Interfacial Reaction of Cu/SAC305/Cu and Co-P/SAC305/Cu Solder Joints under High Current Density
Authors: Long Ting , Chen Yuqian , Fan Tao , Rong Jing , Chen Tao , Yang Donghua 
Published: January 2023

Abstract
The size of solder joints in electronic packaging is gradually decreasing, which directly leads to a sharp increase in the current density experienced by the solder joints. Therefore, it is of great significance to study the effect of electromigration on the interface of the lead-free solder. In this paper, the effect of electromigration on the microstructure of Cu UBM and Co-P UBM solder joints was compared. By comparing the morphological changes of CoSn3 and Cu6Sn5 at the interface, combined with the calculation of the thickness of the intermetallic compound, it was found that the consumption rate of Co-P UBM in the solder joint was much lower than that of the Cu substrate. Moreover, when the Co-P UBM is completely consumed, the consumption rate of the Cu substrate is also significantly reduced.
Analysis of Point Contact Isothermal Elastohydrodynamic Lubrication Characteristics of a New Type of Trigeminal Universal Coupling for Automobile
Authors: Xu Yutian , Yao Chuanqing , Yang Yan. 
Published: January 2023

Abstract
This thesis designed a new type of trigeminal universal coupling structure that changes the original surface contact sliding friction into point contact rolling friction. We analyzed the characteristics of isothermal elastohydrodynamic lubrication to ensure new construction on the drive shaft stability, reliability, and durability. First, we established a contact model of the improved new structure and analyzed the isothermal elastohydrodynamic characteristics of the point contact. Then we studied the input shaft frequency, load, deflection angle, and lubrication characteristics. Research indicated that the other being equal, the faster the input shaft frequency could lead to a thicker oil film, a higher oil film pressure, and a higher secondary pressure peak. The higher load could cause the thinner oil film thickness, the lower oil film pressure, the later position where the pressure begins to increase, and the less obvious second pressure peak. The greater deflection angle could bring about the thicker oil film thickness, the higher oil film pressure, the earlier position where the pressure began to increase, and the earlier position at which the secondary pressure peak was located. This phenomenon was more pronounced in the contact center area.
Comparison of the Measurement Results of PIV with Different Tracer
Authors: Mao Yuhong , Yang Lufeng , Chen Chao , Wang Yue 
Published: January 2023

Abstract
Particle Image Velocimetry (PIV) was used to measure the solenoidal vector field of the Taylor-Couette flow with different tracers. It can be seen that both of them, the polyamide and flocs can be a suitable performance tracer particles for PIV in flow field measurement. The results indicated that the instantaneous velocity vector maps obtained with different tracer particles which could denote the characteristics of the flow structure, the size and the vortex centers of the vortex. At the meantime, the experimental results demonstrated that the velocity vector obtained by the flocs generated in real-time as tracer particles was similar with suitable performance to those obtained by polyamide.
Research on the influence of cutter roll optimization of rotary tiller on its Operation performance
Authors: Wu Tiebin , Cai Wangfei , Song XinBin , Tan Yawen 
Published: January 2023

Abstract
Rotary tillers often have shallow plowing depth and serious leakage problems in the specific working process, resulting in a decrease in the rate of soil breaking and stubble breaking, causing damage to mechanical devices. In this paper, we conducted a field test on the popular self-propelled rotary tiller to obtain the changes in the operating Indexes of various types of knife roller operation with time under three types of tillage environments; we conducted a force analysis and finite element analysis on the IT245 rotary tiller to obtain the stress effect and deformation of the rotary tiller during the operation of the cutter roll; we aimed to study the operating performance and working mechanism of the rotary tiller through test and simulation to explore the path of optimizing the cutter roll.
Study on X-ray testing of buried polyethylene pipeline thermal fusion welding
Authors: Li Qiang , Li Weihan , Li Yanfeng , Yang Jie 
Published: January 2023

Abstract
Thermal fusion welding is a common method for high-density polyethylene (HDPE) pipelines. However, defects are easy to occur at the joints in the welding process, causing hidden danger. In this study, HDPE pipes with thermal fusion welding defects were made and the X-ray technology was used for detection. The results show that the testing effects of different defects are quite different. The X-ray cannot detect cold-welding defects. The weld seam of the over-welding in the negative is narrowed. Besides, the unfilled holes collapse during welding, resulting in poor detection results. The filled holes can be detected.
Gate Ringing Analysis and Driving Circuit Design of GaN HEMT
Authors: Fu Beinan , Xu Mochen , Dong Baolei , Liu Tao 
Published: January 2023

Abstract
GaN HEMT can operate at a high switching frequency because of its characteristics, but there are also related problems. This paper analyzes the negative effects of switching oscillations of GaN HEMT, introduces the design criteria of its driving circuit, and analyzes the causes of the Miller effect and gate ringing under the influence of high-frequency parasitic parameters. Then, the corresponding suppression strategies for the above two phenomena are given, and the design of the driving circuit is introduced. Finally, the validity and rationality of the designed driving circuit are verified by experiments.
Research on Dynamic Characteristics Analysis Method of Spindle-Flywheel Rotor System of Inertia Friction Welding Machine
Authors: Jin Quan , Sun Baoyu , Zhang Gang , Guan Yingjun 
Published: January 2023

Abstract
A rotor is a special vibration system whose mechanical characteristics change with rotating speed. Taking the spindle-flywheel rotor system of inertia friction welding machine as the research object, in order to explore the variation law of critical speed and the unbalanced response of rotor system at different node positions, according to the special form of the spindle-flywheel rotor system, the combined flywheel set is simplified as a node of a lumped mass model, and the Riccati transfer matrix method and finite element method are used to calculate respectively. The error of the Riccati transfer matrix method is less than 4% compared with the finite element method, which proves the rationality of an equivalent flywheel node. Compared with the finite element method, the Riccati transfer matrix method, which simplifies the flywheel model, not only ensures accuracy but also shortens the calculation time. This method is obviously more suitable for calculating the spindle-flywheel rotor system model of an inertial friction welding machine. In addition, this method can also calculate the unbalanced response. When the unbalanced mass distribution is closer to the head end of the spindle, the unbalanced response vibrates more strongly at the second-order natural frequency, and the rotor response during vibration can be predicted.
Effect of vacuum sealing on corrosion resistance of high-velocity arc sprayed coating
Authors: Deng Chunyin , Lu Zhuang , Lu Haifeng , Liu Chenwei , Wu Shuhui , Qin Enwei 
Published: January 2023

Abstract
Thermal spray coatings commonly have pores and micro cracks in their structure. Corrosive medium will pass through pores and micro cracks in corrosive conditions and damage the substrate, leading to coating failure and reduced service life. In this study, vacuum impregnation sealing (VIS) and conventional impregnation sealing (CIS) were used to seal high-velocity arc-sprayed NiCr-based coatings. The cross-sectional microstructure of the coating and its porosity are observed by optical microscopy. Energy spectrometry and scanning electron microscopy were used to measure the sealant’s penetration depth. corrosion behavior was studied by neutral salt spray testing and electrochemical methods. The results showed that the average depth of sealant penetration by VIS is 275 m, almost three times greater than that of CIS. Better corrosion resistance was indicated in the coating sealed by VIS, which had a smaller corrosion current density and a more noticeable passivation zone than the coating sealed by CIS. The coating sealed by VIS showed no rust stains after 432 hours in the salt spray corrosion environment, but the coating sealed by CIS showed corrosion rust spots after 96 hours. The coating sealed by VIS appeared to have greater corrosion resistance, providing experimental support for its use in engineering.
Effect of different top electrodes on dielectric properties of Pb0.3Sr0.7TiO3thin film
Authors: Hou Shuang , Li Xiuneng , Gu Zhehan , Xu Liang , Liu Kai , Mao Xueyin , Jian Hongwei , Yuan Qiaoqiao 
Published: January 2023

Abstract
The PST thin films with different top electrodes were prepared by magnetron sputtering and Sol-gel, respectively. The effects of different top electrodes on Dielectric and Tunable Properties of the films were studied. It is found that the comprehensive properties of the PST films can be improved by using suitable top electrodes. When the dielectric tuning amount of PST thin films using Au/Cr dielectric tuning value is 71.4%, the dielectric loss is 0.02004, and the figure of merit (FOM) is 35.7, which has optimal dielectric properties. At the same time, the purpose of replacing precious metals (Au) with cheap metals (Cu) is realized.
Method for Detecting Electrical Interface in Sea Area Based on Active Electric Field
Authors: Chen Cong , Wu Xu , Yang Jingxuan , Sun Jiaqing 
Published: January 2023

Abstract
To obtain the direction and distance of the electrical interface in the sea, the active electric field of the electric dipole and two three-component electric field intensity sensors are used to detect them. First, the structure design of the active electric field detection device is given, and then a method for active electric field detection of the electrical interface in the sea area is proposed, that is, the effect of the electrical interface on the active electric field is equivalent to the effect of the mirror electric dipole, locating the position of the mirror dipole can be done by measuring the change of the field strength, and then the interface parameters can be determined according to the symmetrical relationship between the position of the mirror dipole and the source dipole. Both simulation analysis and laboratory test results show that the interface detection method is feasible. The related research provides new ideas for target detection in the sea.
Study on the influence of layout angle on static stiffness and longitudinal grip of tread blocks
Authors: Zhou Shenghao , Wang Shuogui 
Published: January 2023

Abstract
The static stiffness and longitudinal grip of the tread block are important parameters of the tire, affecting the performance of the tire, such as braking, steering, noise, and side slip properties. In order to study the influence of the layout angle of the tread block on the static stiffness and longitudinal grip of the tread block, a theoretical model of the change of the static stiffness of the tread block with the layout angle is introduced, which is considered the effect of the compression on the deformation under sliding conditions. A finite element model of the static stiffness of the tread block changing with the layout angle is established in ABAQUS, and the conclusions obtained are in good agreement with the theoretical model. On this basis, the changes in the longitudinal grip of the tread block under different layout angles are explored, and the longitudinal grip of the tread block is increased and then decreased with the increase of the layout angle, and the increase rate before reaching the peak is less than the decrease rate after reaching the peak. Comparing and analyzing the shear stress nephogram of the load-bearing slip tread block under different layout angles, it is found that when the layout angle changes, the shear stress of the tread block will be redistributed according to certain characteristics, thus affecting the longitudinal grip of the tread block.
Loose bolt detection method based on wavelet packet decomposition with CNN
Authors: Xing Yuhua , Geng Huan 
Published: January 2023

Abstract
Loose bolts in PV mounts can affect the smooth operation of the system. If the loose bolts are not detected in time, the PV modules may fall off and cause the mounts to collapse in serious cases. The ultrasonic wavelet packet decomposition (WPD) combined with convolutional neural network (CNN) is proposed as a detection method to address the problem that the ultrasonic signal collected when the bolt is loose indistinctively. First, the ultrasonic signal with bolt loosening information is decomposed into four layers of wavelet packets to extract the energy composition of the feature vectors of each sub-band signal; second, the CNN model is designed and the network is trained with the feature vectors as samples; finally, the discrimination of bolt loosening conditions is achieved. The feasibility of the method is verified through experiments, and the experimental results show that the accuracy of the model is improved from 95.64% to 99.92% compared with the original data training model, and from 86.96% to 99.92% compared with the support vector machine (SVM).
Design of a battery early warning system based on the single-chip microcomputer
Authors: Yan Chengen 
Published: January 2023

Abstract
There is countless news of disasters caused by battery damages, such as explosions, electricity leaks, and thermal runaways each year, resulting in millions of dollars of losses, which highlights the scarcity of an effective damage detection system. However, early-stage damages cannot be detected by current detection methods accurately. This design uses the LTC6811-1 chip to monitor the current and voltage data of the cell and then transmits the data to the ATMEGA328-AU single chip, where the data are processed before being displayed on a PC screen. The principle of detecting damages is to compare the fluctuations in detected data with the pre-set data, i.e., the voltage and current data of discharges of a standard normal cell. If the fluctuation is significantly different in a short time, the cell is considered to be damaged. This offers a new alternative for battery monitoring with earlier warning messages sent and improved details about the damage.
Compressed Sensing: Theory and Applications
Authors: Wang Hanbo 
Published: January 2023

Abstract
Compressed sensing is a new technique for solving underdetermined linear systems. Because of its good performance, it has been widely used in academia. It is applied in electrical engineering to recover sparse signals, especially in signal processing. This technique exploits the signal’s sparse nature, allowing the original signals to recover from fewer samples. This paper discusses the fundamentals of compressed sensing theory, the research progress in compressed sensing signal processing, and the applications of compressed sensing theory in nuclear magnetic resonance imaging and seismic exploration acquisition. Compressed sensing allows for the digitization of analogue data with inexpensive sensors and lowers the associated costs of processing, storage, and transmission. Behind its sophisticated mathematical expression, compressed sensing theory contains a subtle idea. Compressed sensing is a novel theory that is an ideal complement and improvement to conventional signal processing. It is a theory with a high vitality level, and its research outcomes may substantially influence signal processing and other fields.
Effect of different parameters on processing efficiency in electrochemical machining
Authors: Zhou Guanlin , Adayi Xieeryazidan , Shang Zhongsheng 
Published: January 2023

Abstract
To explore the influence of different processing parameters on the efficiency of electrochemical machining and the surface morphology, the influence of different processing parameters on the removal of spikes was simulated by COMSOL Multiphysics simulation software. And combined with experiments, the influence of different processing parameters on electrochemical machining micro-surface was analyzed and compared. The results showed that the removal amount increased with the increase of machining voltage, machining time, and electrolyte concentration, and decreased with the increase in the machining gap. The appropriate processing parameters not only reduce the surface roughness from 2.56μm to 0.57μm, but also change the difference between the surface micro high point and the micro low point from 280μm to 170μm, and the finishing effect is greatly improved.