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SSRN 2024年

作者： Bai, Ru Xue Guo, Hong Xia Zhang, Hong Zhang, Feng Qi Ma, Wu Ying Ouyang, Xiao Ping Zhong, Xiang Li The School of Materials Science and Engineering Xiangtan University Xiangtan411105 China Northwest Institute of Nuclear Technology Xi’an710024 China The Science and Technology on Reliability Physics and Application of Electronic Component Laboratory CEPREI Guangzhou510610 China Zhejiang University China

The microphysical mechanism of proton-induced single-event burnout (SEB) effect in P-GaN power devices was investigated by experiments and simulations. The experiment results show that when the proton energy is 100 MeV, the proton flence reaches 1.38×1011 p·cm-2, and the bias voltage is 600 V, the device will burnout. The transport and deposition processes of particles in the failure event were simulated by Monte Carlo and TACD methods. The simulation results show that the nuclear reaction of protons with the material of the device leads to the generation of many electron-hole pairs. Under the action of the electric field, electrons are rapidly collected at the drain electrode, and holes accumulate under the gate. The accumulation of charge under the gate lowers the potential barrier, producing the bipolar effect and the back-channel effect. These two effects drive more electrons toward the drain, which leads to a large current breakdown in the drain. Notably, the additional electric field significantly impacts the SEB generation. © 2024, The Authors. All rights reserved.

关键词： Monte Carlo methods

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Enhanced Inverter Hybrid Fault Diagnosis Through RAM and CNN Integration

Enhanced Inverter Hybrid Fault Diagnosis Through RAM and CNN...

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International Conference on reliability, Maintainability and Safety,ICRMS

作者： Linghui Meng Lin Li Yuanyuan Jiang Science and Technology on Reliability Physics and Application of Electronic Component Laboratory China Electronic Product Reliability and Environmental Testing Research Institute Guangzhou Guangdong China Anhui University of Science and Technology School of Institute of Artificial Intelligence Huainan Anhui China Anhui University of Science and Technology School of electrical and Information Engineering Huainan Anhui China

ISBN: (数字)9798350329988

ISBN: (纸本)9798350329995

Deep learning has been widely used in inverter open-circuit fault diagnosis; however, traditional neural networks only extract signal features of inverter faults without distinguishing between significant and minor features. To address this limitation, this paper proposes a diagnostic method for inverter hybrid faults that combine reverse attention mechanism (RAM) and convolutional neural networks. The proposed method highlights important features by utilizing RAM to reverse the attention and prune the minor features. In addition, long short-term memory is used to learn temporal information between the features. Finally, fault classification is performed using fully connected layers. Simulation experiments indicate that the proposed diagnostic method significantly improves fault diagnosis accuracy. Compared to traditional neural network fault diagnosis methods, our proposed method achieves up to 8.07% higher diagnosis accuracy, thereby validating its effectiveness.

关键词： Fault diagnosis Deep learning Accuracy Neural networks Random access memory Feature extraction Inverters Safety Convolutional neural networks Long short term memory

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Structural reliability Analysis Method Based on Regular Vine Copula Model with the Asymmetric Tail Correlation

SSRN

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SSRN 2023年

作者： Liu, Xin Lai, Hao Liu, Kai Wu, Shaowei Li, Qiqi Wang, Fang Zhou, Zhenhua The State Key Laboratory of Mechanical Transmissions Chongqing University 400044 China Hunan Province Key Laboratory of Safety Design and Reliability Technology for Engineering Vehicle Changsha University of Science and Technology Changsha410114 China

Considering the asymmetric tail correlations between variables in reliability analysis, a new structural reliability analysis method based on regular vine copula models is proposed. Firstly, a product of multiple pair-copula functions and marginal density functions based on regular vine copula models are used to construct the joint probability density function. Meanwhile, the asymmetric copula functions are introduced into the candidate construction sets of pair-copula functions for the asymmetric tail correlations between variables. Secondly, the Kendall rank correlation coefficient and the Akaike Information Criterion (AIC) are adopted to select the optimal pair-copula functions. Based on the theory of AIC, the optimal pair-copulas can be selected when the minimum AIC value is obtained. Thirdly, taking the difference of multi-dimensional correlations into account, six different regular vine copula models are used to construct the multivariate joint probability density function and the corresponding reliability analysis based on six types regular vine copula models with the asymmetric tail correlation are proposed. Finally, three numerical examples and an engineering example are investigated to verify the validity of the proposed method. © 2023, The Authors. All rights reserved.

关键词： reliability analysis

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A calculation method of gear tooth surface wear considering the center distance error

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Wear 2025年 570卷

作者： Wang, Hongbing Feng, Shicheng Yin, Lairong Hu, Bo Su, Jie Liu, Huihua Zhou, Changjiang Hunan Provincial Key Laboratory of Safety Design and Reliability Technology for Engineering Vehicle Changsha University of Science and Technology Changsha410114 China Xuchang Tobacco Machinery Co. Ltd. Xuchang461000 China Beijing Engineering Research Center of Precision Measurement Technology and Instruments Beijing University of Technology Beijing100124 China State Key Laboratory of Advanced Design and Manufacturing Technology for Vehicle Hunan University Changsha410082 China

In gear transmission, manufacturing/installation error and bearing radial clearance led to the variation of the center distance, changing the contact characteristic and subsequently affecting the wear behavior and the fatigue life of the tooth surfaces. In this work, a center distance error model of the gears with the manufacturing/installation error and the bearing radial clearance was derived, and a nonlinear dynamic model of the gear pair considering the variation of the center distance was established. The contact pressure distribution on the tooth surfaces under the dynamic load was obtained by combining the gear meshing principle and the Hertzian contact theory. A general calculation model of the sliding distance between the contact points in the meshing process of the gear pair was derived based on the single point observation method, and the wear depths of the tooth surfaces under the quasi-static and the dynamic load considering the center distance error were determined based on the Archard's adhesive wear model. The presented work found that the wear depth of the tooth surface under the dynamic load fluctuates around the wear depth distribution under the quasi-static load. When considering the center distance error caused by the manufacturing/installation error and the bearing radial clearance, the maximum wear depth at the tooth tip of the driving gear increases as the actual center distance increases, while the maximum wear depth at the tooth root decreases. As for the driven gear, the maximum wear depth at the tooth tip decreases as the actual center distance increases, while the maximum wear depth at the tooth root increases with the actual center distance. The conclusions in this research work can provide a basis for the strength enhancement design of the gears which performance is affected by the center distance error such small-modulus gear pair. © 2025 Elsevier B.V.

关键词： Gear teeth

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Machine Learning for Complex Systems with Abnormal Pattern by Exception Maximization Outlier Detection Method

arXiv

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arXiv 2024年

作者： Zhang, Zhikun Duan, Yiting Wang, Xiangjun Zhang, Mingyuan School of Mathematics and Statistics Huazhong University of Science and Technology Wuhan430074 China School of Reliability and Systems Engineering Beihang University Beijing100091 China National Key Laboratory of Science and Technology on Vessel Integrated Power System Wuhan430033 China

This paper proposes a novel fast online methodology for outlier detection called the exception maximization outlier detection method(EMODM), which employs probabilistic models and statistical algorithms to detect abnormal patterns from the outputs of complex systems. The EMODM is based on a two-state Gaussian mixture model and demonstrates strong performance in probability anomaly detection working on real-time raw data rather than using special prior distribution information. We confirm this using the synthetic data from two numerical cases. For the real-world data, we have detected the short circuit pattern of the circuit system using EMODM by the current and voltage output of a three-phase inverter. The EMODM also found an abnormal period due to COVID-19 in the insured unemployment data of 53 regions in the United States from 2000 to 2024. The application of EMODM to these two real-life datasets demonstrated the effectiveness and accuracy of our algorithm. © 2024, CC BY.

关键词： Anomaly detection

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Research on linear/nonlinear viscous damping and hysteretic damping in nonlinear vibration isolation systems

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Applied Mathematics and Mechanics(English Edition) 2020年第7期41卷 983-998页

作者： Zhong ZHANG Muqing NIU Kai YUAN Yewei ZHANG Science and Technology on Reliability and Environment Engineering Laboratory Beijing Institute of Structure and Environment EngineeringBeijing 100076China School of Science Harbin Institute of TechnologyShenzhen 518055China College of Aerospace Engineering Shenyang Aerospace UniversityShenyang 110136China

A nonlinear vibration isolation system is promising to provide a high-efficient broadband isolation *** this paper,a generalized vibration isolation system is established with nonlinear stiffness,nonlinear viscous damping,and Bouc-Wen(BW)hysteretic *** approximate analytical analysis is performed based on a harmonic balance method(HBM)and an alternating frequency/time(AFT)domain *** evaluate the damping effect,a generalized equivalent damping ratio is defined with the stiffness-varying characteristics.A comprehensive comparison of different kinds of damping is made through numerical *** is found that the damping ratio of the linear damping is related to the stiffness-varying characteristics while the damping ratios of two kinds of nonlinear damping are related to the responding *** linear damping,hysteretic damping,and nonlinear viscous damping are suitable for the small-amplitude,medium-amplitude,and large-amplitude conditions,*** hysteretic damping has an extra advantage of broadband isolation.

关键词： vibration isolation nonlinear damping Bouc-Wen(BW)model harmonic balance method(HBM)

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Simulation and Experiment of Windage Power Loss of A Shrouded Spiral Bevel Gears under Oil Injection Lubrication

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Chinese Journal of Mechanical engineering 2025年第2期 413-432页

作者： Bo Li Kai Rong Xuyang Zhang Sanmin Wang U-Xuan Tan Xuanyuan Su Laifa Tao School of Mechanical Engineering Northwestern Polytechnical University Department of Engineering Product Development Singapore University of Technology and Design Hangzhou International Innovation Institute Beihang University National Key Laboratory of Science and Technology on Reliability and Environmental Engineering School of Reliability and Systems Engineering Beihang University

During high-speed rotation, the surface of aeronautic spiral bevel gears will generate significant pressure and viscous forces, which will cause a certain amount of windage power loss and reduce the efficiency of the transmission system. Based on the computational fluid dynamics, this paper analyzes the windage power loss of a single spiral bevel gear and a spiral bevel gear pair under oil injection lubrication. In addition, the shroud is used to suppress gear windage loss, and the clearance size and opening angle of the designed shroud are optimized. Finally, by comparing and analyzing the experimental results, the following conclusions were obtained:(1) For a single gear, the speed is the most important factor affecting windage loss, followed by the hand of spiral, and rotation direction;(2) For gear pairs, under oil injection lubrication, the input speed has the greatest impact on windage power loss, followed by the influence of oil injection port speed, temperature and oil injection port pressure;(3) Installing a shroud is an effective method to reduce windage power loss;(4) In the pure air phase, the smaller the clearance between the shroud and the gear surface, and the smaller the radial direction between the shroud and the shaft, the better the effect of reducing windage;(5) In the two-phase flow of oil and gas, it is necessary to design oil drainage holes on the shroud to ensure the smooth discharge of lubricating oil and improve the drag reduction effect.

关键词：

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MEMS Sensitive Structure Sand and Dust Pollution Test and Its Degradation Characteristics

MEMS Sensitive Structure Sand and Dust Pollution Test and It...

引用

International Conference on reliability, Maintainability and Safety,ICRMS

作者： Bin Ruan Chunlong Zhu Tingting Liu Chunhua He Ruiwen Liu Qinwen Huang School of Information Engineering Southwest University of Science and Technology Mianyang China Science and Technology on Reliability Physics and Application Technology of Electronic Component Laboratory China Electronic Product Reliability and Environmental Testing Research Institute Guangzhou China School of Computer Guangdong University of Technology Guangzhou China Institute of Microelectronics Chinese Academy of Science Beijing China

ISBN: (数字)9798350329988

ISBN: (纸本)9798350329995

The sensitive structures of certain devices containing micro-electromechanical system (MEMS) must be directly exposed to the working environment, making them vulnerable to contamination by dust and other pollutants in that environment. Consequently, this contamination degrades the performance of the device, impacting both its working life and stability. Existing test methods, such as GB/T 4208–2017 and GB/T 2423.37-2006, are not entirely suitable for evaluating the sand and dust contamination test of these MEMS devices. To address these issues, a thermistor-based test structure was designed and processed to develop an evaluation method suitable for testing the sand and dust contamination sensitive MEMS structures. The test results indicate that, unlike other hermetically sealed electronic devices, the imposition of electrical stress and cycling of the operating voltage “on-off” during the test does not increase dust accumulation. Furthermore, due to sand and dust contamination, the thermistor value of the device drifts during operation. This drift primarily arises from increased thermal resistance between the heating element of the device and the surrounding environment, resulting from the accumulation of sand and dust, which results in the increase of temperature of the heating element and ultimately results in an elevated thermistor value. This study can provide support for the structural design and package design of MEMS sensitive structures, and provide a basis for the identification and inspection of related products and the development of detailed specifications.

关键词： Micromechanical devices Temperature sensors Thermal resistance Thermistors Voltage Contamination Thermal stability Stress Resistance heating Testing

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Mechanism Analysis of Drivers’ Risk Response Difficulties for Intelligent Driving Safety Design and Development: Results from In-Depth Vehicle-to-Powered Two-Wheeler Crash Data in China

SSRN

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SSRN 2024年

作者： Wang, Xinghua Hu, Lin Wang, Fang Peng, Yong Wu, Xianhui Xiang, Guoliang School of Automotive and Mechanical Engineering Changsha University of Science and Technology Changsha410114 China Hunan Province Key Laboratory of Safety Design and Reliability Technology for Engineering Vehicle Changsha University of Science and Technology Changsha410114 China The State Key Laboratory of Heavy-duty and Express High-power Electric Locomotive Central South University Changsha41007 China

The intelligent vehicles are considered to be potential in avoiding traffic crashes caused by human errors. Reliable intelligent driving in China requires thorough understanding of complex drivers’ risk response difficulties in Chinese background traffic. Based on actual crashes between a vehicle and a powered two-wheeler (PTW) in China, this study analyzed the mechanism of drivers’ risk response difficulties to theoretically support the intelligent driving safety design and development. 113 crashes recorded in six typical vehicle-to-PTW risk scenarios were selected from the China In-depth mobility Safety Study - Traffic Accident (CIMSS-TA) database. The psychological failures and behavioral errors of participants in each risk scenario were analyzed through descriptive statistics. The dominant factors contributory to drivers’ risk response difficulties and their interdependence were explored through 4-item association rule mining (ARM). Furthermore, the characteristics of pre-crash kinematics and the shortcomings of a current approach in identifying potential vehicle-to-PTW crash risks were also discussed based on actual motion data in global and vehicle coordinate systems. The results showed that there was significant heterogeneity in the difficulties encountered by drivers when dealing with various traffic risks. For instance, the information reception failures of drivers (IRF-D) accompanied by the information processing failures of riders (IPF-R) was the most important joint psychological failure pattern in risk scenario 1 and 3, and these crashes were mainly attributed to drivers who failed to yield to straight-going traffic. A typical phenomenon that both participants suffered from information access failures was common in risk scenario 4 and 5, and the crash responsibilities were mainly blamed on these riders running red lights/violating the priority to the right and travelling against the traffic, respectively. Each risk scenario varied dramatically in pre-cr

关键词： Errors

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Spin-polarized sextuple excitations in ferromagnetic materials

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Physical Review B 2022年第24期105卷 245141-245141页

作者： Lei Jin Ying Liu Wei-Wang Yu Xiaoming Zhang Guodong Liu Xuefang Dai State Key Laboratory of Reliability and Intelligence of Electrical Equipment Hebei University of Technology Tianjin 300130 China School of Materials Science and Engineering Hebei University of Technology Tianjin 300130 China

The most fundamental symmetry in condensed matter physics is the crystallographic symmetry, such that solids could exhibit unconventional excitations beyond Dirac and Weyl fermions. Among the unconventional fermions, the sextuple excitation has been predicted in many nonmagnetic materials. However, the study of magnetic sextuple excitations has fallen behind because of the complicated magnetic structures of materials. Here we perform a systematic search for ferromagnetic (FM) sextuple points (SPs) in the absence of spin-orbit coupling. Based on 230 space groups (SGs), we find there are 5 SGs that could host SPs at high-symmetry points. Regarding the stability of the sextuple excitation, we reveal that the minimum little point group at where the SP locates is Td. To support this result, we construct the effective model based on the k·p method, from which the linear dispersion can be read off. Via first-principles calculations, we also identify 67 FM material candidates, which realize the SPs with completely/incompletely spin polarized. To support our theory, we pick one of the FM materials, Rb4O6, as an example in which there is a fully spin-polarized SP. Finally, our work paves the way to study the spin-polarized SPs and provides a platform to realize the spintronic associated with sextuple excitations.

关键词： Ferromagnetism First-principles calculations Spin polarization Topological materials

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