bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Development and Application of Support Vector Machine
Authors: Jun Zhao 
Published: January 2021

Abstract
Support Vector Machine(SVM) algorithm has the advantages of complete theory, global optimization, strong adaptability, and good generalization ability because of it on the basis of Statistical Learning Theory’s(SLT). It is a new hot spot in machine learning research. This article first systematically studies some basic concepts of SVM and the optimization of SVM. In addition, this article also discusses the application of SVM in modern machining, protein prediction and face detection. Through these applications, the performance characteristics and advantages of SVM can be reflected. At the end of the article, some shortcomings of SVM are introduced, and the development trend of subsequent SVM is pointed out accordingly.
Operation Mode of DC Traction Power Supply System and its Feeder Protection
Authors: Ma Min 
Published: January 2021

Abstract
At this stage, DC traction power supply systems are widely used in the development of China’s rail transit. In order to ensure the safety of rail transit, we need to strengthen the research work of DC traction power supply system. We can study and explore from the operation mode of the power supply system and feeder protection measures. Among them, we must pay special attention to feeder protection measures, as far as possible to ensure the safe operation of the DC traction power supply system, so as to ensure the stable operation of rail transit.
A Method of Plasma Quenching in the Gun Barrel
Authors: Luo Tian-Fang 
Published: January 2021

Abstract
In order to extend the service life of the barrel and improve its corrosion resistance and wear resistance, plasma quenching technology successfully processed the inner hole material. The treatment effect is obtained by making the analysis of the microstructure, hardness and tribological properties. The results show that the plasma quenching of the barrel material can form a martensitic hardening layer on the surface, when the surface hardness is increased by 725 HV, and the surface abrasion resistance is enhanced by 10 times. This technology provides a new way to extend the life of the barrel.
This paper analyzes the operation mechanism of integrated circuit electrostatic discharge (ESD) protection device
Authors: Xu Qing 
Published: January 2021

Abstract
Electrostatic discharge, as a common natural phenomenon in daily life, seriously threatens the reliability of integrated circuit products. In order to ensure the yield of the chip, the protection circuit on the chip has become an essential and important module in the circuit design. With the continuous development of integrated circuit technology, chips are developing towards the direction of smaller area, faster speed and higher level of integration, while traditional devices such as simple diodes, tubes and SCR on integrated circuit can no longer complete the protection task of chips under advanced technology. Through the research and discussion of this paper, the methods and strategies of electrostatic discharge protection design of integrated circuits and how to choose the best electrostatic discharge protection scheme for different integrated circuits are basically mastered.
Design of Multi-frequency Analog Transmitter of Magnetic Source Based on Selective Harmonic Elimination Technology
Authors: Yutong Zhang , Yi Liu , Shiqing Cai , Shilong Wang 
Published: January 2021

Abstract
Electromagnetic waves of different frequencies penetrate formations at different depths, so the frequency component of the transmitted waveform determines the detection range of electromagnetic exploration. The selective harmonic elimination pulse width modulation technology was originally used for harmonic elimination. In this paper, SHEPWM is used for harmonic enhancement and the control of harmonics. In addition, the current SHEPWM technology mostly uses various heuristic algorithms, which are not ideal for solving higher-order nonlinear equations. This paper uses the third-order convergence arithmetic mean Newton iteration method to solve the nonlinear equations. The number of solving nonlinear equations can reach 41, and the controllable energy ratio can reach 40% to 50%. Finally, the amplitude and phase of each frequency component of the current waveform can be controlled, which provides a reference for the SHEPWM technology to enhance harmonics.
Recoil reduction method of gun with lateral nozzle controlled by electromagnetic valve
Authors: Si Peng , Qiu Ming , Liao Zhenqiang , Song Jie , Ma Longxu 
Published: January 2021

Abstract
A new recoil reduction method of gun was proposed in this work to reduce the recoil without reducing the muzzle velocity and changing the continuous firing mode. Its recoil reduction mechanism was studied based on the two-phase flow theory. First, combining the gas-solid two-phase flow in the barrel, the electromagnetic control in the electromagnetic valve, the fluid-solid coupling in the piston cavity, and the transient gas flow in the exhaust pipe, an eight-stage mathematical model of the gun propulsion process was established. Next, the propagation law of the rarefaction wave in the barrel was discussed. Then, the propulsion difference between the gun proposed here and the traditional gun was presented. The results showed that the proposed method could reduce the recoil impulse by 38.20% without reducing the muzzle velocity under reasonable matching of the structural parameters.
Research on the Temperature Distribution of the Hollow Conductors in the Self-circulating Evaporative Inner Cooling System for High Power Rectifier Equipment
Authors: Yan Jing , Yu Shunzhou , Cao Rui 
Published: January 2021

Abstract
In the evaporative inner cooling system for high power rectifier equipment, the thyristor and quick fuse are both cooled double-sided via hollow conductors. Different from the previous study on the system with single structure, the self-circulating system for high power rectifier equipment has composite structure. Then the system with composite structure may show different heat transfer characteristics. So in this paper, the temperature distribution of the horizontal and vertical hollow conductors in the self-circulating system was studied through theoretical analysis and simulation.
Flowing model of weld pool during vacuum electron beam welding
Authors: Wu H.Y. , Jiang F. , Wang S.L. , Chen Y.H. 
Published: January 2021

Abstract
The flowing behaviors of weld pool during electron beam welding (EBW) were investigated using T2 copper by physical experiments. A flowing model of weld pool is developed basing on the morphologies observation and analysis. The flow of weld pool for fully penetrated weld is composed of upward convection flow around the keyhole, horizontal flow toward fusion line near top surface and bottom surface, and horizontal flow backward alone weld direction. According to the flowing model, the formation of cavity defection and characteristic of weld in cross-section can be understood.
Research on Three-phase Unbalanced Overvoltage Suppression Method Based on Active Inverter
Authors: Li Yibo , Cao Wensi 
Published: January 2021

Abstract
A three-phase unbalanced overvoltage suppression method based on active inverter is proposed for the three-phase unbalanced voltage caused by the imbalance of three relative parameters in the power grid. According to the zero-sequence current generated by the neutral point in the three-phase unbalanced state in the system, the tracking inverter circuit is correspondingly injected with a certain magnitude and phase current to compensate the three-phase unbalanced current without changing the grid-to-ground insulation. Under the condition of parameters, the three-phase unbalanced overvoltage is quickly and accurately suppressed, and the three-phase voltage balance of the grid is forced. Due to the complex and variable structure of the distribution network, the three-phase unbalance phenomenon is particularly prominent. Therefore, the distribution network is very representative. The reliability of the proposed method is verified by simulation analysis.
Pine-like concentrating power generation device
Authors: Shi Ting , Wang Xincheng , Xiong Xinhong 
Published: January 2021

Abstract
Today, when energy problems are increasingly prominent, the development and utilization of solar energy has become the focus of achieving sustainable energy development. However, due to the dispersion of solar radiation energy and atmospheric absorption, the radiation intensity directly reaching the surface of the earth is relatively weak. The existing linear Fresnel concentrators in engineering are huge in size and have low concentration ratios. In order to increase the concentration ratio of the CSP device, the pine-like CSP device combines the advantages of both the CSP device and the tree-like structure. It has the advantages of low cost, high efficiency, and small footprint, which will solve the problem. This will be a useful attempt to solve the problem of urban solar energy utilization and give new ideas to solve the problem.
Analysis on the Influence of Wind Power Participating in Frequency Modulation on Low-frequency Oscillation in Yunnan Power Grid
Authors: Yang Lei , Gao Jingye , Ma Zun , Huang Wei , Zhang Dan , Xing Chao , Xiang Chuan , He Xin 
Published: January 2021

Abstract
Low-frequency oscillation in Yunnan power grid with a high proportion of hydropower units is prominent. With the continuous access of large-scale new energy sources, it poses a serious threat to the frequency stability of the power grid. Based on the simulation model of Yunnan power grid in 2020, this paper studies the effect of wind power participating in frequency modulation on the damping of Yunnan power grid. Several low-frequency oscillation modes in Yunnan power grid are given through the analysis of two typical operation modes of Xia Da and Chun Xiao. This paper also analyzes the effect of the fan on the low-frequency oscillation mode of Yunnan power grid after adding primary frequency modulation and inertial control. The results show that both inertia control of fan and excessive primary FM sag coefficients will reduce the damping of the system. After wind power is involved in frequency modulation, a favorable effect on the damping of the low-frequency oscillation mode of Yunnan power grid can be produced by setting the control parameters appropriately.
Design and experimental study of minitype modularized fluorescence microscopic imaging system and focusing mechanism
Authors: Zhang Yang , Fu Weiwei , Liu Min , Zhu Hailong 
Published: January 2021

Abstract
In the global in vitro diagnostic(IVD) market, point-of-care testing(POCT) features the largest market share, while POCT in China features small market share. With the development of consumption upgrading, urbanization and medical reform of China, this kind of real-time detection without central laboratory features huge market demand and potential. POCT is a testing method, which can obtain test results in just few minutes with portable equipment and supporting reagents. In this paper, a minitype modularized fluorescence microscopic imaging system is proposed, which is used for blood cells detection, microbial observation and pathological section scanning. In order to meet the needs of portable, miniaturized and chip-type, a linear objective lens switching and focusing mechanism (LOLSFM) has been designed and developed, which changed the rotating disk switching mode of existing microscope. Finally, the precision and verticality of the LOLSFM are verified by experiments. The imaging quality of minitype modularized fluorescence microscopic imaging system.
Intelligent Anti-virus Mask Based on Gas Detection Sensor
Authors: Gong Yide , Wang Yiting , Chen Jin 
Published: January 2021

Abstract
This article developed an intelligent anti-virus mask, which is composed of MQ-135 sensor, single-chip microcomputer, valve mechanism and so on. When there is no poisonous gas, the valve of the canister of the mask is opened to breathe normally; when there is poisonous gas, the valve of the canister of the mask is closed and an alarm is issued, and air enters and exits through the canister. Experiments show that the gas mask can accurately detect the concentration of alcohol gas volatilized by alcohol diluents of 30%, 50% and 80% concentration, and trigger the mask to perform alarm and protective actions in a timely and accurate manner. The experiment verifies the safety and versatility of the smart gas mask, indicating that the product has high engineering application value and practical promotion significance.
Numerical Analysis and Experimental Study on High Frequency Piezoelectric Feeding Device of Block Materials
Authors: Li H S , Li S Y 
Published: January 2021

Abstract
According to the needs of ultrasonic vibration feeding, we developed an ultrasonic piezoelectric feeding device. The device with unrestricted length and width and the feeding speed is uniform. we analyzed feeding the boundary conditions and calculated the expression of the average feeding speed. Using ANSYS to analyze the relevant parameters of feeding vibrator, we made the piezoelectric feeding vibrator and carried out a series of experiments to test the feeding effect by using Laser Doppler vibrometry. The results showed that the amplitude of the first order longitudinal vibration is maximum when the excitation frequency is 34.7kHz; When the feeding device is at the excitation frequency and the driving voltage is 130V, the feeding effect of the heavy material with smooth surface is very good (M10×30 bolts, M20 nuts); Materials with rough surface and lighter than 0.5g have almost no feeding capacity (tablets and grains), and the feeding device has certain selectivity for materials; When the mass of material is 72g, the feeding speed can reach 60.45mm/s. The study provides a reference for the research of ultrasonic feeding device.
Automatic analysis model of power grid infrastructure project cost level
Authors: Lin Yubin , Hu Zhenda , Zhang Chengwei , Fu Benzhao , Zhang Shiming , Hua Xiaolu 
Published: January 2021

Abstract
Under the development of large-scale power grid investment, precise investment management has important guiding significance for improving power grid investment control and efficiency. In this paper, combined with the current situation of power grid infrastructure project cost management and pricing, using the ABC prediction method, through the analysis of cost price mode and characteristics, the cost theory and method innovation and application are carried out. This method is innovative and verified by experiments.
Vibration test and structural optimization analysis of axle box bracket
Authors: Wang Hongquan , Yang Jing , Niu Chengliang 
Published: January 2021

Abstract
The bracket cracked and ground cable broken have occur to axle box many times on certain line metro vehicle. In view of this kind of accident, vibration test, vibration analysis, modal analysis as well as structure optimization are carried out for the axle box bracket of the subway. The test results show that the first transverse bending mode of the bracket is excited by the line vibration, so, it breaks due to vibration fatigue in the resonant state. The simulation results show that the modal frequency can be increased by thickening the bracket and optimizing its structure, so that avoiding resonance phenomenon and increasing its fatigue life. Finally, experiments are carried out to further verify the conclusion, and the structure that performs best can be chosen among multiple optimizations.
Finite Element Analysis of Thermal Load Characteristics of Dry Dual Clutch
Authors: Xie Chao , Wu Guiyu , He Shijie , Zhang Yong , Tian Jie 
Published: January 2021

Abstract
The dry dual clutch of a passenger car is taken as the research object, and its three-dimensional model is established by software CATIA. On this basis, the thermal load characteristics of the dry dual clutch under the condition of multiple starting on the ramp are analyzed by software ABAQUS. The analysis results show that the temperature rise and thermal stress of the parts caused by the friction heat are within the normal range, which indicates that the designs of the pressure plate and the intermediate driving plate meet the requirements. This study obtains the distributions of the transient temperature field of the clutch friction pair under the conditions of the multiple starting, which has an important reference value for the design and optimization of the dry dual clutch.
Online Over voltage Monitoring Method Based on Contactless Induction Technique
Authors: Lu Yufeng , Wang Jialin , Su Yi 
Published: January 2021

Abstract
The operation experience and research shows that over voltage is the main factor which caused grid insulation damage in the power system, but also the main reference option of electrical equipment in insulation conditions selection. Research on system broadband transient current sensing technology based on advanced magnetic field sensors for non-contact measurement, research on system broadband over voltage sensing technology based on advanced optical electric field sensors for non-contact measurement, and development of new micro-sensing technology Distributed connection of non-contact sensing terminals, building a sensor network system for transparent sensing of transient information in substations, realizing passive and wireless communication design, realizing transparent sensing of incoming and outgoing transient information in the station, portable and easy to install, which is the transient information of the power grid Obtain analysis to provide solid data support, greatly improve the level of transient information monitoring in the substation, and improve the reliability of power grid operation.
Research and Application of Transient Transparent Sensing Technology in Substations Using Internet of Things to Distributely Connect Non-contact New Broadband Sensor
Authors: Lu Yufeng , Wang Jialin , Su Yi 
Published: January 2021

Abstract
When the equipment in the substation undergoes major disturbances (such as short-circuit failure, system oscillation, frequency collapse, voltage collapse, line lightning intrusion, etc.), electrical quantities (voltage, current, frequency, etc.) will undergo transient changes. This process is to correctly analyze the accident. The basis of cause can be used to evaluate the operating status of equipment, find fault points, and quickly deal with faults. However, the current domestic transient information perception in substations still needs to be developed: 1) The existing system data sources are PT and CT data, which are restricted by the bandwidth of PT and CT, and the high-frequency monitoring accuracy is not high; 2) the construction and maintenance of centralized screens are complicated. Using a large number of secondary cables; 3) the redundancy is small, and it is not easy to increase and upgrade. Therefore, it is urgent to develop a new type of distributed substation transient information sensing technology, to develop a system wide-frequency transient current sensing technology based on advanced magnetic field sensors to achieve non-contact measurement, and to develop a system broadband transient based on advanced optical electric field sensors to achieve non-contact measurement.
Troubleshooting of a 330MW turbo generator unit during commissioning
Authors: Ma Lyuzhou 
Published: January 2021

Abstract
During the commissioning stage of a 330MW turbo generator unit, several serious defects occurred, such as low vacuum of condenser, abnormal vibration of shafting and bearing damage. Through fault analysis and vibration test, the hidden danger in design, manufacture and installation were found out and solved, the unit successfully completed 168 hours full load test run and put into operation.
Study on Control Strategy for Composite Power Supply System of EV
Authors: Tian Liyuan , Liu Xiaofei 
Published: January 2021

Abstract
At present, countries all over the world are vigorously developing new energy vehicles. Many countries and regions have introduced policies to stop the production and sales of traditional energy vehicles. However, the large-scale industrialization of pure electric vehicles has encountered the constraints of power batteries, and its main problems are reflected in the specific power of the power battery is low. This paper analyzes the current situation of electric vehicle composite power supply, points out the problems and solutions of electric vehicle energy storage system, in order to obtain the expected development and test results.
Failure analysis of 15CrMo catalytic settler
Authors: Jiang Chengjun , Zou Xiaohui , Wang Wei , Li Qian 
Published: January 2021

Abstract
The thinning failure of 15CrMo catalytic settler occurred in a heavy oil catalytic unit of a factory after service for 8 years. The thinning failure reason of the catalytic settler shell was analyzed by macroscopic inspection, metallographic examination, microscopic inspection, chemical composition analysis of the coke layers and oxides of iron test in the outer shell coke layer. The results showed that the working temperature exceeds the anti-oxidation temperature of 15CrMo in an oxidation environment, causing severe high-temperature oxidation thinning on the outer shell of the settler.
Theoretical research and application development of self-sensing micro-flow injection device
Authors: Huang Jie , Shi Liping 
Published: January 2021

Abstract
In this study, the main content is based on theory and application of piezoelectric ceramic digital micro-injection, analyzing the first inverse piezoelectric effect and secondary positive piezoelectric effect of piezoelectric ceramics through theory and experiments, and using its principle to design self-sensing digital micro-injection structure. This paper designs a kind of digital micro-injection device which is based on the first inverse and secondary positive piezoelectric effect by according to the theoretical research and experimental verification of piezoelectric ceramic’s piezoelectric effect. Push the syringe plunger under the action of the piezoelectric ceramic’s first reverse piezoelectric effect to achieve a fluid flowing. At the same time, secondary piezoelectric effect can sense the injection volume to achieve self-sensing microinjection. Designing the overall structure of the program and validate the feasibility of the program is reasonable and practicable through feasibility experiments.
Construction of Evaluation Index System for the Adaptability of Narrowband Internet of Things and Power Business
Authors: Wang Yao , Yun Liang , Sun Xiaoyan 
Published: January 2021

Abstract
With the continuous extension of Smart Grid from the grid side to the user side, the expansion of emerging business is deepening day by day. In terms of terminal access quantity demand of provincial companies, from the original substation of 100 kilo level to the 10 kV distribution system of 100 000 class and the user terminal of 1 million or even 100 million level. Therefore, massive terminal communication is an urgent problem to be solved in power communication network. At present, the State Grid Corporation of China is planning to build terminal communication access network, mainly using optical fiber and Narrow Band Internet of Things wireless technology, mainly to solve the 10kV distribution system; and the communication access of tens of millions or even hundreds of millions of user terminals urgently needs a suitable communication technology to solve. At present, NB-IOT technology has the characteristics of enhanced coverage, ultra-low power consumption, mass access, etc., which can meet the above requirements. This paper mainly describes the construction of NB-IOT technology adaptability evaluation index system, introduces the evaluation method of power narrowband Internet of things, and the evaluation results and analysis of adaptability.