bluuebunny/crossref_metadata_2025 huggingface dataset:
Preface
Authors: Asnafi Nader
Published: November 2022

Over the last 4 years, MEIE has been held in various locations, including Hangzhou (2018 & 2019), an online conference due to COVID-19 (2020), and a hybrid event in Kunming (2021), attracted speakers and participants from 12 countries and regions including Australia, Canada, China, Malaysia, Singapore, South Korea, Sweden, the United States...

The Fifth International Conference on Mechanical, Electric and Industrial Engineering (MEIE 2022) was co-organized by China Institute for Quality Research (Shanghai Jiao Tong University) and Ningbo University, which was supposed to be held on May 24-26, 2022 in Sanya, China. Due to the COVID-19 situation and focusing on the health and well-being of the conference participants, the organizing committee decided to hold MEIE 2022 virtually/online on June 24-25, 2022. This event attracted over 80 participants from 6 different countries and regions, and addressed both basic research and the societal/industrial-technological needs within mechanical, electric and industrial engineering.

Conference program was divided into 3 sessions: keynote speeches, oral presentations and poster presentations. We are honored to invite 5 experts to give the impressive keynote speeches. And there were 22 oral presenters and 14 poster presenters. During these sessions, presenters shared their latest research findings. Audiences were actively participated in discussion and voting for the best presentations.

The proceedings of this conference comprise 98 accepted contributions from 234 submissions, all the papers have been through rigorous peer review to meet the requirements of international publication standards. Many thanks to the authors for their valuable contributions and to the attendees for their active participation. We would like to express our gratitude to the reviewers, who provided constructive criticism and stimulating comments and suggestions to the authors. We are grateful to the organizers, technical program committee for their precious time and advice, as well as internationally renowned scientists who acted as keynote speakers at the conference.

Finally, our sincere gratitude goes also to the IOP Publishing editors and managers for their helpful cooperation during the preparation of the conference proceedings.

On behalf of the Organizing Committee of MEIE 2022.

List of Technical Program Committee is available in this Pdf.
Four window functions for simulation of vibration transmission effects in a planetary gear set
Authors: Liu Zongyao , Wang Yadong , Gan Quan , Ban Xinxing , Liu Shihua
Published: November 2022

Analysis of vibration spectrum is one of the main investigation methods in the research filed for condition monitoring on planetary gear sets. However, such a gear set always exhibits complicated spectral structures in the vibration spectrum because of the planet carrier’s rotation, and the path distance from the fixed transducer to the moving meshing point will always be changed, which brings a modulation effect on the vibration signals received by a fixed transducer. Aiming to investigate the vibration transmission effects of planetary gear sets, four different window functions are introduced in this paper to simulate the transmission path changing with time i.e. the path between moving meshing position and a fixed transducer. Comparison results show that the Hamming window function may be a more suitable choice to model the transmission path changing with time in the planetary gear set.
Influence of assembly preload on bearings performance
Authors: Zhang Manyi , Li Runlin , Zhang Chun , Liu Beibei
Published: November 2022

Taking a transmission system under alternating axial load as an example, this paper builds the shafting model in Romax. By using the orthogonal experimental design method, the influence law of different factor level combinations on bearing performance is analyzed. The simulation results show that the axial assembly preload has a great influence on the contact stress load distribution in the inner raceway, the housing hole design tolerance of transition fit has a second influence, and the shaft design tolerance of interference fit has a smaller influence. The preload design parameters under service conditions are optimized: shaft design tolerance (k6), housing hole design tolerance (K6) and axial assembly preload (30 μm).
Research on small muzzle brake design and optimization
Authors: Li Peng , Wu Dalin
Published: November 2022

In order to improve the efficiency of the small muzzle brake used in the anti-material rifle, the calculation model of the efficiency of the muzzle brake is established, and the main structural parameters of the small muzzle brake are optimized by using the MATLAB optimization toolbox. After optimization, the efficiency of the muzzle brake is improved by 38%. The test results show that the improved small muzzle brake can meet the requirements of anti-material rifle.
Validation on the mean friction velocity of an atmospheric boundary layer flow reproduced by large-eddy simulation in terms of kinetic energy conservation
Authors: Suzuki Hiroki , Hasegawa Yutaka
Published: November 2022

This study presents a validation of large-eddy simulation to reproduce normalized mean friction velocity in an atmospheric boundary layer flow in terms of kinetic energy conservation uncertainty. A primary finding of this study is that the normalised mean friction velocity of the atmospheric boundary layer is suggested to be insensitive to kinetic energy conservation errors. The present study approaches the sensitivity of the normalized friction velocity, which is one of the most fundamental statistics in the atmospheric boundary layer, to the uncertainty. The nearly complete conservation of kinetic energy in the present numerical framework is verified in an inviscid homogeneous isotropic fluctuation field. Then, the present analysis is applied to reproducing turbulent channel flows as direct numerical simulation and large-eddy simulation based on the previous studies before the present work analyses the present atmospheric boundary layer. The present analysis is then used to analyze the normalized friction velocity in the atmospheric boundary layer. The values of the friction velocity obtained in the previous study are in good agreement with that of the present study.
Analysis and optimization of abnormal furnace pressure in a CFB boiler
Authors: Duan Caili , Xin Shengwei , Wang Hu , Ma Chi , Yan Pu , Liu Xiaojun , Hao Jie , Liu Yun
Published: November 2022

An induced draft fan frequency converter fault during the operation of a CFB unit, the furnace pressure fluctuates greatly in the process of the fan switching from frequency conversion mode to power frequency mode automatically. By mean of analyzing the reasons of the abnormal event, corresponding improvement measures were put forward and the experience and lessons were also summarized. It provides a reference for preventing the occurrence of such events and dealing with similar events quickly for thermal professionals. Meanwhile, thermal workers could be reminded to pay attention to distributed control system (DCS) configuration management and the test work after configuration.
Design and performance analysis of multi-wheeled lateral and longitudinal rocker arm series-parallel robot
Authors: Wang Fude , Kou Zhihui , Li Teng , Li Wenhao
Published: November 2022

The six-wheeled rocker robot and the eight-wheeled rocker robot have strong obstacle-surmounting and terrain adaptability, which are widely used in lunar and Mars exploration, military operations, and field rescue. However, for the terrain environment with low friction coefficient and more complex unstructured terrain environments such as ice and snow roads, the six-wheeled rocker robot and the eight-wheeled rocker robot are not enough, so the rocker arm robot with stronger ability to overcome obstacles and adapt to the terrain is needed. In order to solve the above technical problems, this paper innovatively designs a multi-wheeled lateral and longitudinal rocker arm series-parallel robot. Firstly, Creo3.0 is used to create a new three-dimensional model of a series-parallel robot with multi-wheeled lateral and longitudinal arms. Then, the 3D model of the robot is imported into Adams2018 to build a virtual prototype simulation model. Finally, through the construction and simulation analysis of various obstacle-surmounting terrain environments such as vertical obstacles, slopes and potholes, the adaptability, obstacle-surmounting, safety and maneuverability of the robot to different terrain environments are studied. The conclusions obtained in this paper can provide a reference for the innovative design of the obstacle-crossing mechanism of the multi-wheeled lateral and longitudinal rocker arm series-parallel robot, and the improvement of the obstacle-crossing performance, adaptability, maneuverability and safety performance on complex terrain.
Multi-objective optimization of shaftless rim-driven thruster based on ISIGHT
Authors: Liu Liangliang , Jiang Wen , Liu Zhiwen , Yu Ruixue , Bian Tao
Published: November 2022

This paper performed the multi-objective optimization of shaftless rim-driven thruster (RDT) based on ISIGHT platform to improve the efficiency and thrust of the shaftless RDT. The diameter, the rotational speed and the number of the investigated blades of RDT were set to known. The multi-objective optimization variables were the blade pitch P/D and the blade area ratio A0/Ae of the investigated blades of RDT. The results show that under the condition that the propulsion efficiency is slightly improved compared with the Original blade, the optimized blade can increase the RDT thrust coefficient by about 15%. The Merit coefficient has increased by about 3%.
Analytical algorithm for time-varying friction force and torque of pitting helical gear
Authors: Wang Zhengbing , Shi Lubing , Liu Zhongming , Pei Bang , Zhao Yukai
Published: November 2022

Friction excitation is an important factor affecting gear vibration and noise. This paper analyzes the variation law of sliding friction during helical gear meshing, and the calculation algorithm of friction force and torque of helical gear is derived. The effects of working parameters on the friction force and torque are analyzed based on the time-varying friction factor model. The calculation method of the friction force and friction torque of pitting helical gear is given by establishing the quadrilateral pitting model on the tooth surface of the helical gear. The influence of pitting parameters on the friction force and torque is analyzed, which can provide the research basis for the dynamic response analysis of pitting gear.
Motor bearing fault diagnosis based on local characteristic-scale decomposition and support vector optimized by sine cosine algorithm
Authors: Yi Zichun , Xiao Chun , Xiao Shiyun , Wan Yu
Published: November 2022

When the motor bearing fails, the nonlinear and unstable characteristics of the vibration signal will lead to a low fault identification accuracy. This paper proposes a fault diagnosis method for motor bearings based on local characteristic-scale decomposition (LCD) and sine-cosine algorithm to optimize support vector machine. In this paper, the LCD algorithm is used to decompose the vibration signal, and screened out the effective intrinsic scale components (ISC) component. Then, Sample Entropy and Permutation Entropy are extracted from the filtered components. For the selection of parameters c and g of SVM, this paper introduces the sine and cosine optimization algorithm (SCA) for position update optimization, and builds an SVM model to obtain a classification model for motor bearing faults after training on the data set. After importing the remaining test data set into the classification model for testing, the fault classification accuracy results of the motor bearing can be obtained. The results of the simulation experiments show that the recognition rate of motor bearing faults based on LCD and SCA-SVM is 98.75%.
Inspection and analysis of a 500kV main transformer excessive acetylene failure
Authors: Zhang Shuai , Yu Bing , Zhao Lin , Song Guoquan , Wei Bo , Lin Haofan , He Jian , Li Lele , Wang Bin , Cui Zhuye , Fang Chengwei , Lu Hongkun , Zou Xiaofeng
Published: November 2022

B phase of the no 2 main transformer of 500 kV XX substation was suddenly stopped on August 20, 2021 due to acetylene and an abnormal sudden increase. Acetylene reached 10.5uL / L, far exceeding the acetylene attention value of 1.0uL / L, and there is a trend of continuous growth. An internal inspection was carried out after the power outage, and no obvious abnormality was found. Then it was sent to factory for de-oiling and drying. Inspection found the following problems: 1. The upper and lower iron yoke clamps of main transformer and their pull straps, the fourth pull strap shielding cover from the left of lower clamp on the high pressure side was found to be abnormal; 2. Check the iron core silicon steel sheet, found that there are about 15mm burrs between the iron yoke (high-voltage side) core stages under the side post position; 3. There is a black mark at the connection part of low-voltage lead and the casing oil, but no signs of discharge or overheating are seen; 4. Check that there is no obvious abnormality in other parts of the body, such as insulation, lead wires, and electrical shielding. Combined with the inspection situation, analyze specific causes of the failure and propose follow-up improvement suggestions.
Study on the characteristics of the potential rise of shell under VFTO in the GIS pumped storage power station
Authors: Kang Chao , Zhang Zongyang , Wang Zhiyuan , Wang Jingqi
Published: November 2022

Compared with the traditional GIS station, complex wiring and operation mode of pumped-storage plant diversity, working condition of frequent transformation, makes the plant to produce very fast transient overvoltage (VFTO) probability increase greatly. VFTO will form a transient coupled to the GIS shell casing transient earth voltage (TEV), and then to station personnel safety and the reliability of the secondary equipment poses a great threat. But at the moment because of the limitation of testing technology such as understanding of the academic study of TEV is lack of system. Based on a typical 500 kV gis pumped-storage power station, this paper established a system equivalent model of GIS, network frame and calculates the amplitude, frequency spectrum characteristic of the TEV and influence on VFTO characteristics, and analyzes the fault location, power supply mode, branch bus, the influence of vertical grounding electrodes on the TEV characteristics, For the characteristics of the TEV rules and parameters. Research on TEV characteristics of GIS of pumped storage power station has important reference value for further perfecting relevant theories.
Research on power electronic transformer with hybrid energy storage system
Authors: Zhu Longji , Jiang Wenzhong
Published: November 2022

Power electronic transformer is a new type of power equipment for building smart grids. However, when the grid voltage drops deeply, it will cause its output voltage to be distorted and affect the stable operation of the load. The hybrid energy storage system composed of lithium battery and super-capacitor through bidirectional half-bridge DC/DC converter and dual active bridge DC/DC converter is proposed to be connected to the low-voltage DC side of power electronic transformer, so as to stabilize the output voltage of the power electronic transformer. The dual active bridge DC/DC converter and the bidirectional half-bridge DC/DC converter use phase-shift control and droop control, respectively. The result of the simulation shows that the addition of the hybrid energy storage system can enable the power electronic transformer to have the ability to compensate for the deep voltage drops, thereby improving the reliability of the system.
Design and simulation of non-uniform electric field using mesh electrodes for electrorheological micro valves
Authors: Zhang Jiahui , Huang Jingyu , Xu Luning , Han Li
Published: November 2022

The refresh rate of two-dimensional tactile information for visual impaired people using electrorheological (ER) technology is directly related to the flow rate of an ER valve. The bigger the flow rate is, the faster the tactile information is refreshed. For a parallel electrodes ER valve configuration, due to the limitation of Braille standard to the width of ER valve, the gap of flow channel which is also the gap of parallel electrodes is the only adjustable parameter to benefit the flow rate and at same time enhance operating voltages which contribute a big part of costs to a two-dimensional tactile information display system. A new mesh electrodes configuration is introduced to decouple the flow rate from the gap of electrodes while the flow cross section is determined by parameters of mesh electrodes. A quantity of effective electric field strength of an ER interaction space unit is used to evaluate the anisotropy electric field governed by mesh electrodes. The influences of geometrical parameters of mesh electrodes and applied voltages on the effective electric field strength were analyzed by using COMSOL Multiphysics. The simulation results show that the effective electric field strength increases with applied voltages and wire diameters, and decreases with electrodes gap and mesh clearances. These results provide fundamental laws for designing an ER micro valve governed by non-uniform electric field to some ER applications.
Analysis of shielding failure of transmission line based on pilot model
Authors: Zou Yu , Xie Zhenjun , Song Yinguan , Wang Deyin , Wang Xiang
Published: November 2022

Since the main way of power transmission in China is overhead line transmission, some overhead lines are in a harsh outdoor environment. Among them, the bypass attack is more serious. Shielding Failure is a severe form of lightning damage. Based on the situation, this article studies the lightning shielding phenomenon of transmission lines. This article uses the pilot development model to simulate the lightning strike process, analyzes the different target objects of the lightning strike, and elaborates and calculates the lightning shielding trip rate. In addition, by changing the protection angle, the height of the tower, the ground inclination of the area where the line is located, and the number of lines, the impact of these four factors on the lightning shielding trip rate is discussed. According to the influencing factors, measures to strengthen the lightning protection performance of the line are proposed.
Research on continuous current characteristics and operating load characteristics of EGLA in UHVDC lines
Authors: Wang Zhiyuan , Kang Chao , Zhang Zongyang , Guo Jie
Published: November 2022

In order to ensure the safe and stable operation of UHVDC transmission system, line arresters with series gap (EGLA) are often installed on UHVDC lines in engineering. When the line is struck by strong lightning, the series gap of EGLA will be broken down and the lightning will flow through the SVU. After lightning flows, EGLA needs to cut off the continuous current in time and reliably to restore the high resistance state. Therefore, the research on the characteristics of continuous current and operating load of EGLA is related to the design and selection of EGLA parameters, which has important engineering significance. However, due to the lack of UHVDC experimental platform, the relevant research is less, resulting in the lack of basis for determining SVU parameters. Based on the ±800 kV UHVDC transmission line from northern Shanxi to Nanjing in Jiangsu Province, this paper uses the method of control variables to simulate and study the characteristics of EGLA under different lightning strike modes, line positions and transmission capacities, and draws the conclusion that compared with back flashover on the tower, the peak value of EGLA under lightning shielding failure is smaller but the absorbed energy is larger, and the influence of transmission capacity is more obvious. When the lightning shielding failure on the middle tower of the line, the absorbed energy of EGLA is the largest and the continuous current is smaller.
Research and analysis on suppression and influence of transformer direct current bias
Authors: Wang Ting , Chen Kun , Zhang Kanjun , Zhang Longen , Hu Xingyang
Published: November 2022

DC bias generates a large DC component in the windings of the transformer in operation, thereby generating harmonics, causing vibration, noise, and overheating. In severe cases, it can cause damage to the transformer, which will affect the safe and stable operation of the AC system. This article takes the DC bias of the main transformer of a 220kV substation as an example, and uses the capacitance isolation method to suppress the DC bias. Due to the addition of capacitor equipment at the neutral point, the zero-sequence impedance of the main transformer and the change of the zero-sequence impedance of the power grid are changed, which has an impact on the zero-sequence (directional) current protection and ground distance protection. Through theoretical analysis and simulation research verification, for general 220kV substations, the capacitor DC isolation method (1.2Ω) can be used to suppress DC bias, which has a small impact on the relay protection and does not need to adjust the related protection settings.
A novel space vector modulation strategy for legs parallel three-level inverters to reduce common-mode voltage
Authors: He Haiyang , Zhang Guorong , Chen Weilun , Wu Zhizhen
Published: November 2022

In order to increase the converter’s rated power, the parallel connection of legs between inverters has been an effective way. The common-mode voltage is one of the main problems of this inverter. Based on the special connection mode of legs parallel inverter, the output voltage can be regarded as the output of a five-level inverter. Therefore, this paper proposes a space vector modulation based on the virtual five-level to suppress common-mode voltage. The traditional SVPWM algorithm contains a lot of trigonometric function calculation, which slows down the response speed of the system. This paper proposes a novel coordinate system division method, which avoids trigonometric function calculation and reduces the amount of calculation. The effectiveness of this method is verified by Matlab / Simulink simulation.
Study of indoor and outdoor 1000kV GIS layout
Authors: Xu Li , Wang Lin , Su Guang , Xiong Zaibao , Geng Xiaohong , Li Yanning
Published: November 2022

As the backbone Grid for STATE GRID Corporation of China, UHV projects require high safety and reliability. 1000kV GIS switchgear is the most important part of UHV AC substation. Deepening the research on its layout and improving the safety and stability can provide strong technical support for the subsequent UHV AC project construction, which is of great significance. The defect and failure rate of indoor GIS is lower than that of outdoor GIS, but the initial cost of indoor GIS is higher than that of outdoor GIS layout scheme. According to the operation related data, this paper carries out the design scheme research, technical scheme comparison and life cycle analysis of indoor and outdoor layout of 1000kV GIS equipment.
Design of universal power supply and distribution ground test system based on modularity
Authors: Zhao Zheng , Li Anqi , Diao Weihe
Published: November 2022

To solve the problems of high functional requirement, complex structure and poor versatility of manned spacecraft power supply and distribution ground test equipment, a modular universal ground power supply system (PSS) is designed. The functions of the system cover the functions of wire instruction opening, parameter measurement and state detection of the interface between the manned spacecraft and the ground equipment, and realize the universal and extensible configuration. This paper provides a general architecture design method for complex manned spacecraft power supply and distribution ground test system.
Design and application of unified control system for laboratory electric energy metering standard device based on RPA
Authors: Zhao Xingwang , Wu Shuang , Ai Zhen , Yu Jian , Wang Yijie
Published: November 2022

In view of the limited integration of laboratory electric energy metering standard device and production management system, and faced with problems such as ineffective production coordination, low detection data collection efficiency, high data dispersion, and low degree of laboratory resource sharing, the research on the integration technology of AI and RPA-based measurement standard equipment and upstream production management system was carried out, and put forward a method to detect the efficient development of production collaboration and the fusion application of experimental data. Using the above technologies, the unified control system for laboratory electric energy metering standard device based on AI and RPA is developed, which realizes the scheduling control of the laboratory metering standard device verification, accurate and efficient collection and application of detection process data. Comprehensive and strong support for the digital transformation of measurement and mass transmission and quality inspection business. Through practical application, it is verified that the unified control system can seamlessly integrate laboratory metering standard device, realize coordinated control and provide expansion ideas and practical guidance for the promotion and application of digital laboratory construction.
Spatial resolution analysis of passive bistatic radar using low-orbit navigation augmented signals
Authors: Wang Jinbo , Fu Hongwei , Wang Binbin , Liu Liguo
Published: November 2022

Aiming at the problem that the traditional monostatic ambiguity function is inconvenient to analyze the spatial resolution of the passive bistatic radar, this paper proposes a method to analyze it in a given airspace by using the spatial distribution of the ambiguity function. This method converts the time-delay Doppler distribution of the traditional ambiguity function into the spatial distribution near the reference target, which makes it more suitable for the intuitive analysis of the spatial resolution capability of the passive bistatic radar. This new method is used to analyze the target resolution capability in the designated airspace when Navigation augmented signals transmitted by the low-orbit communication satellite is used as the illuminator of opportunity. The distribution of the ambiguity function is transformed from a pushpin shape under the monostatic time delay-Doppler shift to a flat “sandwich biscuit” shape in space. The shape is closely related to the geometric relationship of the bistatic radar. Through the spatial distribution of the ambiguity function, the target resolution in a given airspace can be directly observed, which is convenient for analyzing the spatial resolution capability of the signal under different spatial geometric relationships. This also provides convenience for the optimal selection of the location of the illuminator of opportunity and receiving station.
Identification of vulnerable node groups in wind power grids based on K-order structure entropy
Authors: Li Lijuan , Li Yue , Liu Zhiqiang , Zeng Yiwei , Ding Gangwei , Zhang Qingsong
Published: November 2022

Power outage accidents are caused by chain failures caused by the failure of vulnerable components affecting a certain range of components. Identifying the spread impact range of vulnerable nodes can effectively improve the system’s vulnerability. Large-scale wind power grids connection increases the complexity of the power systems and brings new challenges to the identification and simulation of vulnerable nodes. In this paper, a method for identification of vulnerable node groups in wind power grids is proposed. The method identifies the central node of the vulnerable node groups in wind power grids based on interval electrical number, and determines the influence range of the central node through the minimum K-order structure entropy, so as to obtain the vulnerable node groups in wind power grids. An IEEE-39 bus system with wind power is used to verify the rationality of the proposed method, which provides a reference for the prevention and control of interlocking faults of power grids with wind power.
Analysis of imbalanced voltage on 35kV side after single phase replacement of 500kV transformer
Authors: Yang Yong , Zhang Jing , Jin Yongtao , Li Wenbo , Wei Bo
Published: November 2022

After the B-phase of the 500kV transformer was replaced, the three-phase voltage on the 35kV low-voltage side was imbalanced and the neutral point displacement voltage was relatively high during the start-up test. For this problem, firstly, the calculation method of neutral point displacement voltage is given through the method of vector analysis and equivalent circuit, and the reasons for the imbalance of the three-phase voltage are analyzed. According to the measured parameters, the PSCAD/EMTDC power system simulation software is used to establish a model, and the steady-state operating characteristics of the system are simulated and calculated. Theoretical analysis and simulation calculation have determined that the cause of the imbalance of the three-phase voltage is the inconsistency between the ground capacitance of the low-voltage winding and the capacitance between the high-voltage and low-voltage windings of the B-phase transformer than that of the A-phase and C-phase. The impact of the capacitance between the high-voltage and low-voltage windings of the transformer is far greater than the capacitance of the low-voltage windings to ground on the imbalance of three-phase voltage to ground on the low-voltage side of the transformer.
Design and analysis of rocket engine system with electric pump as subsystem
Authors: Zhou Chuang , Yu Nanjia , Wang Jue , Jiao Bowei , Guo Xuesong , An Shan
Published: November 2022

Electric pump feed systems use the high-speed and high-performance motor to replace the traditional turbine as the driving machine of pumps. A new feed system scheme is proposed in which a small-flow electric pump pressurizes hydrogen peroxide to the gas generator. The system keeps the performance of the engine at a high level, while being able to achieve continuous regulation and depth regulation. The balance calculation method and reliability allocation method are used. The results show that, the power of the electric pump for fuel path and oxidizer path is 600.0 W and 1732.6 W, respectively. The total mass of the engine is 69.76 kg, and the mass percentage of the electric pump system is small, less than 3.2% of the overall system mass. The effect of the electric pump system on the engine mass is small, but it improves the engine regulation capability. The reliability of this engine system is calculated to be 0.9802, which is not less than the target value of 0.98 with a certain margin, according to the reliability assigned to each combined part.
Modification of the line-of-sight motion error for squinted SAR after real-time PRF adjustment
Authors: Li Yueli , Li Zesen , Wang Jian , Liu Ke , Zhou Zhimin
Published: November 2022

The motion error of a multi-rotor unmanned aerial vehicle (UAV) leads to severe image blurring for mini synthetic aperture radar (SAR) systems. The along-track displacement error usually is compensated in advance through real-time pulse repetition frequency (PRF) adjustment. And then, only the cross-track displacement error is considered in traditional motion compensation (MOCO) algorithms. However, the instantaneous range expression based on the geometry of a squinted SAR shows that the residual along-track displacement error after PRF adjustment cannot be ignored, especially for mini-SAR systems. Therefore, the line-of-sight (LOS) motion error is modified by introducing the residual along-track displacement error. And then, the first and second-order factors for the LOS MOCO are redefined. The experimental results show that the proposed method can reduce the LOS motion error and significantly improve the imaging performance of the squinted SAR mounted on a multi-rotor UAV.
Research on vibration compensation technology of pressure sensors in shock wave overpressure measurement
Authors: Li Xinying , Duan Zhuoping , Long Renrong
Published: November 2022

In the dynamic pressure test of explosion shock wave, the interference of seismic wave and mechanical shock makes the interpretation of shock wave pressure measurement more difficult. In this paper, a comparative test is designed to peel off the vibration signal, and the source of vibration in shock wave measurement and the cause of acceleration parasitic effect of pressure sensor are analyzed combined with the data; Then, according to the experimental conclusions and the working principle of the sensor, a new pressure sensor with vibration compensation function is designed; Finally, the feasibility of the new sensor structure for vibration compensation is analyzed by finite element simulation. The results show that the vast majority of vibration interference signals are output by the sensor’s sensitive elements, and the new sensor with double sensitive element compensation can effectively suppress or eliminate the parasitic output caused by vibration interference. The design of the new structure sensor provides ideas for the design of vibration compensation structure of other pressure sensors, and has a certain reference value.
Application of memory alloy materials in power system
Authors: Lin Haofan , Yu Bing , Lu Lu
Published: November 2022

The shape memory alloy (SMA) is a new kind of metal intelligent material, which has the characteristics of shape memory effect (SME), pseudo-elasticity (PE) and high damping (HD). Therefore, it is widely used in many industries, such as construction engineering, mechanical engineering, space shuttle, energy engineering, medical engineering and so on. In order to solve the heating defects of fittings, the typical six split fittings joints in the main flow circuit of converter station was selected in this paper. And the memory alloy intelligent gaskets and ordinary steel spring gaskets on both sides of the fitting joints were installed. The experimental research on the influence of current on the temperature rise of fittings with different types of gaskets were carried out. The test results showed that the shape memory alloy gasket could automatically generate the deformation force which increased with the increase of temperature, so as to reduce the contact resistance of the joint and the temperature of the contact during operation.
Research on vibration and aging characteristics of memory alloy
Authors: Lin Haofan , Yu Bing , Lu Lu
Published: November 2022

The shape memory alloy (SMA) is a new type of metal intelligent material, which has been widely used in power system such as hardware connector, circuit breaker, disconnector and relay protection. In order to solve the heating defect of fittings, the typical six split fittings in the main flow of converter station was selected in this paper. The memory alloy smart gasket and ordinary steel spring gasket are installed on both sides of the joint. The effects of vibration and aging on the temperature rise of different types of gaskets and pipe fittings were experimentally studied. The test results showed that after long-term power frequency vibration, the temperature rise of memory alloy smart gasket changed little before and after vibration. At the same time, after several temperature rise tests, the temperature rise before and after the smart gasket fittings joint of memory alloy change little.
A brachial artery-based system for blood pressure pulse wave measurement and its signal filtering technique
Authors: Wang Can , Lin Zhenghao , Zhang Zhongli
Published: November 2022

Human blood pressure (BP) and its pulse wave has always been a popular topic since it’s bound up with the heart related risks. In this paper, we mainly focus on the pulse wave of the brachial artery which is also widely used in the measurement of BP, hence we constructed a brachial artery-based system by using multi-Windkessel model and managed to generate a reliable pulse wave signal with adjustable authentic human parameters. On this basis, the signal filtering technique was also discussed. We mixed noises with different amplitude and frequency into the original signal intentionally, then several filters’ performances were compared. The designed combined filter represented a stable performance, and had little error in BP values, which ensure the stability and reliability of the designed system.
In situ monitoring of beam current in electron beam directed energy deposition based on adsorbed electrons
Authors: Liang Zhiyue , Zhang Haoyu , Li Zixiang , Du Dong , Wang Li
Published: November 2022

Electron beam directed energy deposition (EB-DED) is a promising and efficient additive manufacturing technology, but the vacuum environment challenges the in situ parameters monitoring. In this paper, an in situ beam current monitoring method is developed based on the absorbed electrons. A series of experiments show that there is a linear relationship between the absorbed electron current and the impinging beam current. However, this relationship only holds when the beam power density is relatively low. When the power density is high, the absorbed electron current will be lower than the theoretical value determined by the linear relationship. This is mainly due to the massive generation and ionization of metal vapor. The critical power density depends on the melting point of the material. Nonetheless, the deviation of the absorbed electron current at high power density can roughly determine the relative position between the focal spot and the workpiece surface. In addition, the slope of the linear relationship is material-dependent, so this method can also distinguish different materials.
Small excitation self-powered sensing energy harvester for rail traffic condition monitoring
Authors: Qin Yuanjing , Liu Mengzhou , Fu Hailing
Published: November 2022

A small excitation bistable vibration energy harvester for railway transportation is developed for self-powered condition monitoring utilizing low-frequency vibration of key train components. Analyze operational vibration data collected from trains to determine design requirements. A free sliding magnet is placed in a tube with a top fixed magnet and two limit springs, using gravity, magnetism, and spring force to provide two stable positions for the movable magnet. This structure can enter the bistable operating region under small excitation amplitude and has a wide operating bandwidth. Build and test prototypes using conditions similar to real train operating conditions. A wide operating bandwidth (7 Hz-46 Hz) is obtained due to the bistability. Peak output power is 3.17mW measured into a 900 Ω resistive load at 30 Hz and 1.4g.
Research and application of equipment intelligent operation and maintenance platform
Authors: Liu Ying , Hu Longhao , Ding Mingyue , Yang Zheng , Xi Jialu
Published: November 2022

The intellectualization of equipment operation and maintenance is one of the main development directions under the background of intelligent manufacturing. Based on lean theory and an intelligent algorithm, this paper establishes the equipment hierarchical management model and equipment intelligent operation and maintenance framework, introduces the lean management strategy and equipment operation state prediction algorithm in the operation and maintenance framework in detail, and finally realizes the design and development of equipment intelligent operation and maintenance platform. The platform has been proved in a steel structure manufacturing enterprise that it can effectively realize equipment condition monitoring, fault diagnosis, and performance prediction, and has a significant effect in reducing accidental shutdown loss and improving machine utilization.
The IMU/UWB/odometer fusion positioning algorithm based on EKF
Authors: Li Jinwang , Gao Tongyue , Wang Xiaobing , Bai Daizhuang , Guo Weiping
Published: November 2022

High-precision indoor positioning is the basis of factory intelligent management. However, the positioning accuracy will decrease because of the complex environment. This study proposes a multi-sensor fusion framework to fuse the data of Ultra Wide Band (UWB), inertial measurement unit (IMU), and odometer. First fuse the data from UWB and IMU by using EKF to obtain attitude, velocity, and position. And then fuse the speed and output with the odometer output using complementary filtering to increase accuracy. At the same time, the algorithm can output higher frequency positioning data. We evaluate the performance of the algorithm on mobile robots. Experimental data is from a 6-axis IMU and 5 UWB radio sensor devices. And the result shows that the position RMSE of our algorithm is 3.29 centimeters and our comprehensive localization algorithm can increase localization accuracy in complex environments compared with only UWB algorithm.
An ensemble framework based on diversity enhancement and difference indicator for fault diagnosis of rotating components with unknown modes
Authors: Xu Yuhui , Han Dongyang , Jiang Yimin , Li Rourou , Shu Junqing , Tao Jianfeng , Xia Tangbin
Published: November 2022

Rotating components often run continuously at high speed under heavy load, resulting in variable failure modes. Because a priori not-considered fault may occur during the actual operation, it is significant to develop methods that can identify both pre-known types of faults and unknown types of faults. In this study, an ensemble framework based on partial dense convolutional neural networks with multiple diversity enhancement strategies (MDE PD-CNN ensemble) is proposed. Firstly, PD-CNN is employed to improve the generalization ability of the base model. Variety PD-CNN are constructed under multiple diversity enhancement strategies. Furthermore, differences in the output of samples on different base models are measured to detect unknown faults. Both known and unknown faults can be accurately diagnosed based on the ensemble procedure with the difference indicator. Experiments on bearing and gear datasets are conducted to demonstrate the superiority of the proposed ensemble framework.
Vertex functions and their flow equations from the 2PI effective action
Authors: Millington Peter , Saffin Paul M
Published: November 2022

By exploiting the convexity of the two-particle-irreducible effective action, we describe a procedure for extracting n-point vertex functions. This procedure is developed within the context of a zero-dimensional ‘quantum field theory’ and subsequently extended to higher dimensions. These results extend the practicability and utility of a recent, alternative approach to the functional renormalization group programme (see Alexander et al 2021 Phys. Rev. D 104 069906; Millington and Saffin 2021 J. Phys. A: Math. Theor.
54 465401), and clarify the relationship between the flow equations for coupling parameters and vertices.
Fractional Brownian gyrator
Authors: Squarcini Alessio , Solon Alexandre , Viot Pascal , Oshanin Gleb
Published: November 2022

When a physical system evolves in a thermal bath kept at a constant temperature, it eventually reaches an equilibrium state which properties are independent of the kinetic parameters and of the precise evolution scenario. This is generically not the case for a system driven out of equilibrium which, on the contrary, reaches a steady-state with properties that depend on the full details of the dynamics such as the driving noise and the energy dissipation. How the steady state depends on such parameters is in general a non-trivial question. Here, we approach this broad problem using a minimal model of a two-dimensional nano-machine, the Brownian gyrator, that consists of a trapped particle driven by fractional Gaussian noises—a family of noises with long-ranged correlations in time and characterized by an anomalous diffusion exponent α. When the noise is different in the different spatial directions, our fractional Brownian gyrator persistently rotates. Even if the noise is non-trivial, with long-ranged time correlations, thanks to its Gaussian nature we are able to characterize analytically the resulting nonequilibrium steady state by computing the probability density function, the probability current, its curl and the angular velocity and complement our study by numerical results.
Bäcklund transformation and nonlinear superposition formula for the two-component short pulse equation
Authors: Mao Hui , Miao Yuanyuan
Published: November 2022

By means of the reciprocal transformation and the associated equation, a Bäcklund transformation (BT) containing both independent and dependent variables is worked out and studied for the two-component short pulse (2SP) equation. Based on it, the corresponding nonlinear superposition formula (NSF) is also constructed. Through reducing the BT and NSF of the 2SP equation, the BTs and NSFs for the SP equation, the focusing complex short pulse (cSP) equation and the defocusing cSP equation are obtained respectively. By analyzing the range of parameters in the solution, various solutions including soliton solitons, cuspon solitons, loop solitons, breather solutions are divided and their interaction are considered.
Recent progress of the ECRH system and initial experimental results on the J-TEXT tokamak
Authors: XIA Donghui , CHEN Xixuan , XU Dengfeng , FANG Jiangang , ZHANG Junli , WANG Nengchao , YANG Zhoujun , CHEN Zhongyong , DING Yonghua , ZHENG Wei , MA Shaoxiang , WANG Zhijiang , PAN Yuan
Published: November 2022

In order to broaden the range of the plasma parameters and provide experimental conditions for physical research into high-performance plasma, the development of the electron cyclotron resonance heating (ECRH) system for the J-TEXT tokamak was initiated in 2017. For the first stage, the ECRH system operated successfully with one 105 GHz/500 kW/1 s gyrotron in 2019. More than 400 kW electron cyclotron (EC) wave power has been injected into the plasma successfully, raising the core electron temperature to 1.5 keV. In 2022, another 105 GHz/500 kW/1 s gyrotron completed commissioning tests which signifies that the ECRH system could generate an EC wave power of 1 MW in total. Under the support of the ECRH system, various physical experiments have been carried out on J-TEXT. The electron thermal transport in ECRH plasmas has been investigated. When ECRH is turned on, the electron thermal diffusivity significantly increases. The runaway current is elevated when a disruption occurs during ECRH heating. When the injected EC wave power is 400 kW, the conversion efficiency of runaway current increases from 35% to 75%. Fast electron behavior is observed in electron cyclotron current drive (ECCD) plasma by the fast electron bremsstrahlung diagnostic (FEB). The increase in the FEB intensity implies that ECCD could generate fast electrons. A successful startup with a 200 kW ECW is achieved. With the upgrade of the ECRH system, the J-TEXT operational range could be expanded and further relevant research could be conducted.