bluuebunny/crossref_metadata_2025_split huggingface dataset:
Microstructure characteristic of hot formed 22MnB5 steel and its relationship with delayed hydride cracking property
Authors: Wang Hua , Hao Shiyu , Wang Baolei , Kuang Chunfu 
Published: February 2022

AbstractHydrogen-induced delayed cracking is an important factor leading to the failure of ultra-high strength steels during service, thus in this study, the mechanical properties and hydrogen trapping of hot formed 22MnB5 steel considering different content of V (0, 0.05, 0.09 wt.%) and corresponding microstructure were investigated. Slow strain rate tensile tests (SSRT) were applied to obtain the tensile strength and elongation of samples under different medium conditions (air, HCl immersion and electrolytic hydrogen charging). Besides, microstructure and atomic distribution morphology of the samples were detected and analyzed by transmission electron microscope (TEM) and atomic probe tomography (APT) technique. Results showed that both resistances of hydrogen-induced delayed cracking in MnB-V5 and MnB-V9 samples were obviously better than that in MnB-V0 sample, besides, the delayed cracking resistances of MnB-V9 and MnB-V5 samples did not improve with the increase of V content, but basically remained the same. Lamellar residual austenite was found in all samples, but no hydrogen was grasped in the same area according to APT result. There was intragranular cementite in all samples, and it has grasped H in the same position. The carbides formed by V, Ti and other alloying elements were found in MnB-V5 and MnB-V9 and were considered to be an important factor in improving the anti-hydrogen delayed cracking performance of the steel.
Synthesis and performance study of a highly dispersed HPEG-type polycarboxylate superplasticizer
Authors: Lin Zeyu 
Published: February 2022

Abstract
HPEG has long been widely used as an alternative to TPEG. In this study, a new high-performance HPEG-type polycarboxylate superplasticizer PCE-A was synthesized by using H2O2 and sodium hypophosphite/Vc redox initiation system to provide free radicals under aqueous polymerization conditions with HPEG and acrylic acid as the main raw materials. The results showed that the best performance of the synthetic polycarboxylate superplasticizer was achieved when the acid to ether ratio was 4.50, Vc was 0.25%, H2O2 was 0.80% and sodium hypophosphite was 1.7%, which could effectively reduce the amount of admixture without affecting the working performance of concrete, and the concrete strength was higher.
Preparation Process and Quality Characterization of High Density Fine Grain Osmium Target for Coated Cathode
Authors: Ma Junda , Xia Yang , Xie Yuanfeng , Lv Hong , Zhang Chao 
Published: February 2022

Abstract
High quality osmium targets are the key influence in improving the emission performance, lifetime and reliability of M-type cathodes. In this experiment, oxidative distillation was used to prepare osmium powder with a purity greater than 99.99%. The effect of hydrogen sintering and hot pressing sintering processes on the densities and grain size of the targets was investigated. The results show that the oxidation distillation process can effectively separate Os from Si, Fe, Ni, Zn and other impurity elements, and the purity of osmium powder prepared by multiple oxidation distillation was not less than 99.99%. Both hydrogen sintering and hot pressing sintering processes can be used to obtain osmium targets with a density of not less than 95%. However, the sintering temperature and time used in the hot pressing sintering process under pressure assistance are significantly lower than those of hydrogen sintering, which is more conducive to inhibiting grain growth during the high densification sintering process. By optimizing the parameters of the hot pressing sintering process, the sintering temperature of 1500°C and the holding time of 1.5h resulted in an osmium target with a density of 99.11% and a grain size of ≤12. XPS analysis of the highly dense fine crystalline osmium targets prepared by hot pressing sintering showed that the C and O mass fractions on the surface of the targets were 0.85% and 4.43% respectively, and the C and O contents gradually decreased with increasing etching depth. The above highly dense and fine crystalline osmium targets can be used in the M-type cathode standard coating process to obtain high purity, dense and strong bonded osmium films.
Effect of shear thickening property of polymer on relative permeability
Authors: Zhang Wenlong , Hou Jian , Liu Yongge , Du Qingjun 
Published: February 2022

Abstract
The relative permeability at a high Darcy velocity was estimated by combining a numerical simulation model that considers the rheology of polymer in shear thickening region. After verifying the robustness of the method, the effect of shear thickening property of polymer on relative permeability was studied. The results show that when Darcy velocity exceeds 17.61 m/d, the apparent relative viscosity of polymer solution begins to increase, and the rheology of polymer changes from shear thinning to shear thickening behavior, which reduces water relative permeability. For water relative permeability model, as Darcy velocity increases, water relative permeability at residual oil decreases in a power function and exponent of water relative permeability model increases linearly.
Study on performance stability of Polycarboxylate Superplasticizer prepared at different temperatures
Authors: Zhong Lina , Wang Zhaopeng , Lin Zeyu , Fang Yunhui 
Published: February 2022

Abstract
The effects of initial dropping temperature, amount of ferrous sulfate and dropping time on the performance of Polycarboxylate Superplasticizer were studied, and the measures to maintain the performance stability of Polycarboxylate Superplasticizer from 15 °C to 40 °C were discussed. The results show that the stability of the process is better when the initial dropping temperature is 20°C-30°C. When the temperature is higher than 30 °C, the stability of the process can be achieved by prolonging the dropping time or reducing the amount of FeSO4; When the temperature is lower than 15 C, the performance can be improved by increasing the amount of FeSO4, so as to achieve the stability of the process.
Analysis on Influencing Factors and Control Measures of Metal Materials Heat Treatment Deformation
Authors: Yu Yanli 
Published: February 2022

Abstract
The scientific application of heat treatment technology is aimed at improving the performance of metal materials, which is very important for improving the utilization rate of metal materials. In the process of h meat treatment, metals are easily affected by factors and deform, which leads to theetal materials can’t be used normally. Therefore, it is necessary to deeply analyze the factors affecting heat treatment, and then formulate effective control measures to reduce the probability of metal material deformation and improve the service performance of metal materials. Based on this, this paper explores the influencing factors and control measures of heat treatment deformation of metal materials.
Study on Illumination Measurement Method of Lighting Environment Based on RBF Neural Network
Authors: Zhang Yujie , Li Si 
Published: February 2022

Abstract
In order to better measure the indoor light environment, evaluate the quality of the indoor lighting environment, and improve the requirements of lighting comfort, a camera image measurement illuminance method based on RBF(Radial basis function)neural network is proposed, and the camera sensor imaging theory is derived and analyzed to obtain the environmental illuminance and camera sensor The relationship between the parameters, the establishment of the RBF neural network model, by building an experimental system platform, collecting data sets to train the network model, fitting the neural network model parameters to obtain the illuminance measurement model, and use the image gray level and the reference point illuminance as the neural network Input and ambient illuminance as output. The prediction result shows that the error between the illuminance value predicted by the neural network and the actual measured value of the illuminance meter is within 10lx, and the relative error is less than 8%, which meets the requirements of lighting building design standards. Therefore, this method can achieve rapid measurement of the illuminance in the environment, and has a relatively high High precision.
The Design of Low-concentration Dust Detection System Based on Mie Scattering Theory
Authors: Zhang Zhaopeng 
Published: February 2022

Abstract
According to the requirement of low-concentration dust emission in China, this paper designed a low-cost and high-precision dust detection system based on Mie scattering. Through theoretical analysis, the relationship between the intensity of scattered light and the concentration of soot is obtained. The laser emitting unit, signal receiving unit and STM32 data processing unit are designed. The driving principle of laser modulation and the principle of selective signal amplification of weak signal are analyzed. The host computer program is written with LabVIEW software, and the test data are displayed on the front panel of the host computer. The experimental results show that this system has high sensitivity, fast response, good repeatability, and can be measured online for a long time, which means this system has good practicability.
Research on the Method of Measuring Soil Water Content by Time Domain Reflectometry
Authors: Cui Jiawei , Kong Saibo 
Published: February 2022

Abstract
Time domain reflectometry (TDR) can calculate the water content by testing the dielectric constant of the rock and soil medium, but the TDR measurement results under time domain conditions are susceptible to the influence of soil conductivity. This article introduces the basic theory of TDR measurement, then uses the transmission scattering matrix to describe the transmission equation, analyzes the dielectric constant in the frequency domain, simulates the TDR waveform with matlab based on the Debye model, and fits the simulated waveform to the measured waveform, and then according to the simulated waveform The matching degree proves the feasibility of calibrating the dielectric constant of the soil. Taking clay as the measurement object, finally fitting a simulation waveform with a higher degree of matching with the measurement waveform, which proves the feasibility of the method and has certain reference value for the study of the TDR method of measuring soil dielectric constant and water content.
Analysis on harmonic characteristic of transformer DC bias caused by metro stray current
Authors: Cheng Xinxiang , Ni Yanru , Yu Kun , Zeng Xiangjun , Zhuo Chao , Han Wei 
Published: February 2022

Abstract
With the continuous improvement of the economic level, urban rail transit has been vigorously developed. However, the metro stray current will be generated during the actual operation of urban rail, which will cause transformer DC bias along the metro line. In order to effectively evaluate the influence of the transformer on the DC bias under urban rail operation, the stray current distribution model with single and double-ended power supply mode was established, and the numerical calculation of the stray current was realized. Based on the real-time dynamic change characteristics of the stray current, a synchronous simulation model of the transformer DC bias was established, and the harmonic characteristics of the transformer excitation current were further analyzed. The simulation test shows that when the direct current is injected into the neutral point of the transformer, the excitation current waveform is asymmetrical along the positive and negative semi-axes, and the odd and even harmonics coexist. And the influence of transformer DC bias is weakened when transformer air core reactance is increased. The characteristic quantities such as excitation current amplitude, waveform characteristics, and harmonic content have been quantitatively analyzed in this paper, which has certain guiding significance for evaluating the influence of transformer DC bias.
Research on Ultrasonic Quantitative Evaluation Technology of Complex Defects Based on Neural Network
Authors: Li Xinglong , Liu Shengguo , Cheng Shuo , Lin Jindi , Liu Rongchun , Wang Leyu , Zhou Zhilin 
Published: February 2022

Abstract
As one of the five non-destructive testing methods, ultrasonic testing is widely used because of its accurate positioning, high sensitivity and simple operation, but the method is still difficult to locate and quantify complex shape defects. The large amount of data required for ultrasonic imaging leads to low detection efficiency. Based on this, the article establishes an inversion system for evaluating complex shape defects, which includes ultrasonic A-scan technology, BP neural network, image processing technology and signal processing technology. The system is verified by simulation and experiment. The results of the defect inversion are as follows: the similarity coefficients are all greater than 0.89, the maximum value can reach 0.95; the area error is less than 11%, the minimum value can reach 1.2%; the centroid x error is less than 12%, the minimum value can reach 1.58%; the centroid y error is less than 11%, the minimum value can reach 2.15%. The result of defect inversion further verifies the accuracy and reliability of the complex defect inversion system.
Sharing VSG Operation with Synchronous Generator
Authors: Hasabelrasul Hashim , Cai Zhenjiang , Sun Lei , Suo Xuesong 
Published: February 2022

Abstract
While several synchronous generators (SGs) are substituted through virtual synchronous generators (VSGs), some SGs remain in today’s microgrids. And the majority of the research assumes that VSG mimics SG characteristics, allowing it to function in parallel among SGs. However, few studies have gone to great lengths to study this concept. As a result, the paper’s goal system is a microgrid that runs both VSG and regular SG in parallel. In this article, new parameters for the VSG are designed in parallel with the SG. Then, in an independent microgrid, identical VSG-VSG and scenario SG-VSG configurations are fixed to equate the complex activity. The emotional responses contrasted when the load requirement is shared fairly and proportionally.
An integrated method of system maintainability, testability and supportability design and evaluation
Authors: Zhang Huazhao , Liu Baoding , Yu Jinsong , Liang Guozhu 
Published: February 2022

Abstract
General quality characteristics of equipment system have a guiding role for the design, production and use of equipment and are vital for the evaluation of these characteristics. They are important indicators to measure whether the equipment meets the established standard. Aiming at the problem that the design and evaluation process of equipment general quality characteristics are independent and unrelated, this paper proposes an integrated and continuous maintainability, testability and supportability design and evaluation process based on FMECA and MSFG, and designs corresponding evaluation parameters. An impact-based fault mode rating method is also proposed to better evaluate the general quality characteristics of equipment.
Research on Real-time Simulation of Power Electronic Circuits Based on Simscape
Authors: Xu Baohe , Lu Li , Gong Dawei 
Published: February 2022

Abstract
In order to realize hardware-in-the-loop simulation of commonly used power electronic circuits, a method of joint simulation using Simcape and field programmable gate array (FPGA) is proposed. This article adopts a switch modeling method suitable for high-frequency characteristics, namely the switch function method. It effectively solves the problem of rigidity non-convergence in the modeling of the binary resistance method, as well as the transient error caused by the binary LC method when the system state is switched with the increase of the switching frequency, which reduces the simulation accuracy. Taking the single-phase full-bridge inverter circuit as an example, a Simscape model based on the state-space averaging method was established, and the HDL code was automatically generated using the Simscape HDL Workflow Advisor tool, and the hardware-in-the-loop simulation was completed with FPGA. Finally, the simulation results with Simulink comparison verify the effectiveness and feasibility of the method.
Intelligent control of flexible joint based on cooperative learning theory
Authors: Shi Qun , Jia Xiangjie 
Published: February 2022

Abstract
It is complex and time-consuming for obtaining accurate dynamics of industrial robots. The flexibility of the joint not only increases the adverse effects of nonlinear factors, but also makes the controller design of robot significantly difficult. In order to improve the performance of robots containing joint flexibility, cooperative learning (COL) theory is proposed in this paper. Based on this theory, a model-free intelligent controller is trained and successfully applied to the flexible joints. Compared with the conventional PID controller and RBF controller, the cumulative tracking error produced by the cooperative learning intelligent controller is reduced by 38.25% and 31.08%, respectively, and the robustness is improved in the trajectory tracking experiment and the robustness experiment. The experimental results demonstrate the feasibility and effectiveness of the cooperative learning theory.
Influence of Public Mobile Communication System on the Frequency of S-Band Radars
Authors: Yang Jian , Chang Zengtian , Su Dongchu , Li Chenyong , Luo Siwei , Chang BoWei , Qiang Lu 
Published: February 2022

Abstract
Given the interference between public mobile communication system and S-band radars, an applicable interference analysis model was established, the typical frequency parameters of radar and the key parameters of the base station were sorted out, the radiation parameters of the mobile terminal (MT) were tested practically, and the interferences of the base station and MT to radar were calculated. Further, the Monte Carlo method was taken to simulate the system-level lumped interference of the communication system to radar, and an analysis was made on the influence of the communication system on the frequency of radar. The results revealed that the public mobile communication system had severe lumped interference with radar, which may affect radar frequency. Therefore, it is necessary to take measures to protect radar.
Lightweight IT Operation and Maintenance Integrated Monitoring Method for APP System
Authors: Wang Xuyong , Chen Rui 
Published: February 2022

Abstract
Through the operation and maintenance system, the centralized control of the operation state of enterprise equipment can be realized. In order to solve the problem of unstable monitoring effect of traditional methods, untimely risk early warning and high error rate of early warning information, a lightweight it operation and maintenance integrated monitoring method for APP system is proposed. Analyze the actual needs of the monitoring function of the lightweight IT operation and maintenance system, design a targeted IT operation and maintenance monitoring function module according to the analysis results, and give the lightweight IT operation and maintenance process. A lightweight IT operation and maintenance database is established based on fuzzy theory, and data with similar characteristics is simulated to minimize the dispersion of sample data. Finally, in order to achieve integrated monitoring of lightweight IT operation and maintenance, and to improve monitoring efficiency and monitoring accuracy, it is necessary to reduce the dimensionality of multi-dimensional data, which is mainly achieved through principal component analysis. The experimental results show that compared with the traditional method, the method in this paper can obtain accurate early warning information in time in monitoring, indicating that its monitoring effect is better, and it has a certain positive effect on ensuring the safe operation of the IT operation and maintenance system.
IBM Small-Scale Superconducting Quantum Computer Not Gate Error Test
Authors: He Ming , Liu Xiaonan , Wang Junchao , An Jiale 
Published: February 2022

Abstract
Quantum NOT gates play an important role in the process of quantum information conversion. However, when the X-gate operation is executed on a real quantum computer, there is a large deviation between the actual operation result and the theory, which will lead to inaccurate results when the quantum algorithm containing the X-gate operation is executed. In order to facilitate users to understand the error fluctuations of the X gate in time before executing the quantum algorithm containing the X gate operation on the IBM quantum cloud platform, this paper proposes a method to measure the X gate error. By measuring the X-gate error of four small-scale superconducting quantum computers on the back end of the IBM quantum cloud platform, analyze the degree of fluctuation of the actual measurement value of the quantum device; at the same time, under different execution times shots, the influence of the X-gate test is analyzed. The test results show that the measured value of each qubit of different quantum devices fluctuates to different degrees; the execution times of shots are different, and the test results of X-gate error will be affected to different degrees. This test method helps users select the optimal performance of the qubits before executing quantum algorithms with X gate on IBM's small-scale quantum computers.
Object detection based on Yolov4-Tiny and Improved Bidirectional feature pyramid network
Authors: Liu Qi , Fan Xiaoyu , Xi Zhipeng , Yin Zhijian , Yang Zhen 
Published: February 2022

AbstractIn the field of small object detection, Yolov4-Tiny is inadequate in feature extraction and does not make best of multi-scale features. In this paper, an improved BiFPN framework is proposed based on Yolov4-Tiny to increase object detection precision. Moreover, the Yolov4-Tiny is taken as the backbone network and introduce spatial pyramid pooling (SPP) to connect and merge multi-scale regions. Finally, our method can achieve 79.53% map on Pascal VOC dataset, which is 2.12% higher than the original Yolov4-Tiny model.
Finding Discriminative Regions with More Subtle Granularities for Fine-grained Image Classification
Authors: Liu Qi , Xi Zhipeng , Fan Xiaoyu , Yin Zhijian , Yang Zhen 
Published: February 2022

Abstract
Classifying subcategories of the same category (such as birds, cars, airplanes) is mainly to find discriminative features and accuracy regional positions in the fine-grained visual classification (FGVC). In this article, we propose to use global average pooling slice feature maps to find significant discriminative regions without complicated network designs or training operations and use Drop-Block mechanisms to solve the problem of network overfitting. Specially, we use the feature maps of the multi-branches as inputs, and average-pooling them with different sizes of convolution kernels to obtain feature maps that containing deeper and shallow information for getting more accuracy granularities. Our methods are called as More Accurate Multi-Granular Convolutional Neural Network (MAG-CNN). Compared with other networks with more complex designs, the network only requires common operations such as pooling and convolution to achieve higher accuracy. The MAG-CNN can be trained end-to-end, without any bounding-box, and our method has reached the most advanced performance on three common fine-grained image classification benchmark datasets (CUB-Birds, FGVC-Aircraft, and Stanford-Cars).