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Development of Wind Wake-effect Minimizing Model Based on Combination of Dung Beetle Optimization, Extreme Learning Machine, and Genetic Algorithms

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Sensors and Materials 2024年第3期36卷 1047-1064页

作者： Qu, Li-Nan Li, Hao-Peng Lin, Hsiung-Cheng Li, Ling-Ling State Key Laboratory of Reliability and Intelligence of Electrical Equipment Hebei University of Technology Tianjin300401 China China Electrical Equipment Research Institute of Science and Technology Co. Ltd. Shanghai200436 China School of Electronic and Information Engineering Hebei University of Technology Tianjin300401 China Department of Electronic Engineering National Chin-Yi University of Technology Taichung41170 Taiwan

The wake effect caused by a wind turbine can reduce the wind speed and add turbulence to the wind, thus impacting the power generation efficiency. To effectively enhance the generated power in wind farms, we propose an optimal layout model that is combined with artificial intelligence optimizing algorithms. First, the adaptive genetic algorithm (AGA) is used to optimize the collected wind speed and direction distribution data as the optimization basis. Second, the extreme learning machine (ELM) based on Monte Carlo simulation is used to establish a guidance for determining the turbine relocation from the optimization basis. Simultaneously, the dung beetle optimization (DBO) algorithm is developed to improve the performance of ELM for achieving the optimal solution. The proposed model was tested at six different wind farms and under three different wind condition distribution settings. The simulation results verify that the model is superior to existing algorithms in reducing the wakeeffect impact as well as optimizing the wind farm layout. © 2024 M Y U Scientific Publishing Division. All rights reserved.

关键词： Genetic algorithms

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Topological charge-2 triply degenerate point: Theory and high-throughput material screening

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Physical Review B 2024年第3期110卷 035152-035152页

作者： Zining Hu Lei Jin Chenyao Li Ying Liu Xuefang Dai Xiaoming Zhang Guodong Liu State Key Laboratory of Reliability and Intelligence of Electrical Equipment School of Materials Science and Engineering Hebei University of Technology

The charge-2 (C2) triple point (TP) is a zero-dimensional threefold band degeneracy with a topological charge |C|=2. Different from other types of TP, the C2 TP is expected to have novel physical properties because of its nonzero topological charge. However, the C2 TP is only found in nonmagnetic materials and has not been found in realistic magnetic materials. In this work, we systematically study such fermions in nonmagnetic and ferromagnetic systems. Based on 230 space groups (SGs), we confirm that 13 SGs could host the C2 TP at high-symmetry points. By first-principles calculations and high-throughput material screening, we identify 82 candidate materials, which host a nonmagnetic or ferromagnetic C2 TP. The lattice parameters, magnetic ground states, spin-polarization ratio, and positions of the C2 TP in momentum/energy space of these candidate materials are also given in detail. To support our theory, we take BaPPt and MnBi12O20 as examples for detailed analysis, which host spinless and full spin-polarized C2 TPs. In particular, a long Fermi arc extended in the whole Brillouin zone is clearly observed. Our work paves the way to study the C2 TP and provides candidate materials for future study of physical properties, experimental research, and device application.

关键词： Charge Electrical properties Electronic structure First-principles calculations Surface states Topological materials Density functional theory High-throughput calculations

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Improving the sensitivity of diamond NV center ensemble magnetometer based on microsphere

Improving the sensitivity of diamond NV center ensemble magn...

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2024 International Conference on Optical and Photonic engineering, icOPEN 2024

作者： Zhou, Yangyang Tang, Jiong Ma, Bingxu Qiu, Jian Science and Technology on Reliability Physics and Application of Electronic Component Laboratory China Electronic Produce Reliability and Environmental Testing Research Institute Guangzhou Guangdong510610 China School of Electronic and Information Engineering South China Normal University Foshan Guangdong528225 China

ISBN: (数字)9781510688117

ISBN: (纸本)9781510688100

Diamond nitrogen-vacancy (NV) center ensemble magnetometer is a novel solid quantum magnetometer with high sensitivity and high spatial resolution, which can be used at normal temperature and pressure. However, the low fluorescence collection efficiency of the magnetometer in confocal optical system hinders further improvement in sensitivity. To solve the problem, based on silica microspheres, we propose a method to enhance the excitation and collection efficiency of NV center ensemble in massive diamond. Experimental results show, compared with the NV diamond magnetometer without microspheres, the photon collection efficiency of NV diamond magnetometer coated with a layer of microspheres is increased by 110%. Thus, the sensitivity of the NV center magnetometer is increased by 4 times to 5.3μT/√Hz. © 2025 SPIE.

关键词： Microspheres

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Influence of Monstera riedrichsthalii bionic textures on the tribological and vibration behavior of rolling bearings

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Friction 2025年第3期13卷 153-170页

作者： Risheng Long Qingyu Shang Shaoni Sun Siwei Wang Chi Ma Jianwei Zhang Max Marian Equipment Reliability Institute Shenyang University of Chemical TechnologyShenyang 110142China Liaoning Provincial Key Laboratory of Efficient Chemical Mixing Technology Shenyang 110142China School of Mechanical Engineering and Automation Northeastern UniversityShenyang 110089China China–Spain Joint Laboratory on Material Science Shenyang University of Chemical TechnologyShenyang 110142China Department of Mechanical and Metallurgical Engineering Pontificia Universidad Católica de ChileMacul 690411Chile Institute of Machine Design and Tribology(IMKT) Leibniz University HannoverAn der Universität 1Garbsen 30823Germany

Surface texturing has been proven to be an effective method for improving the lubrication characteristics and tribological behavior of tribo-pairs under various operating *** by the unique Swiss cheese-like leaves of Monstera riedrichsthalii,eight bionic texture patterns were *** influence of vein features,such as costal vein angles(45°and 60°),vein symmetry(symmetric,asymmetric),and elliptical holes,on the tribological and vibration characteristics of rolling bearings was investigated under starved lubrication through a wear test rig and time‒frequency domain vibration signal *** results show that the average coefficients of friction and wear losses of the Monstera riedrichsthalii bionictextured groups are generally lower than those of the smooth *** amplitudes and parameters(i.e.,peak value,root mean square(RMS),and crest factor)of the time-domain vibration signals of the textured groups are greater than those of the smooth group in the early stages,but the vibration parameters of most textured groups are lower than those of the smooth bearings in the later stages,especially those of the groups with elliptical *** amplitudes and power spectral density(PSD)curves of the frequency-domain vibration signals exhibit similar variations to those of the time-domain *** with the smooth reference,the Monstera riedrichsthalii bionictextured group with a combination of 45°secondary-vein angle,asymmetry,and elliptic holes can provide excellent tribological and vibration *** well-lubricating period,average coefficient of friction(CoF),and mass loss can be effectively prolonged or reduced by 37.4%,7.3%,and 43.9%,respectively.

关键词： rolling bearings Monstera riedrichsthalii bionic textures tribological and vibration behavior starved lubrication

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IGBT Performance Degradation Feature Construction and Real-Time Prediction Based on Machine Learning 17th

IGBT Performance Degradation Feature Construction and Real-T...

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17th Annual Conference of China Electrotechnical Society, CES 2022

作者： Wang, Xin Zhou, Zhenwei He, Shilie Jia, Hanguang Huang, Yun The Science and Technology on Reliability Physics and Application of Electronic Component Laboratory China Electronic Product Reliability and Environmental Testing Institute Guangzhou510610 China School of Automation and Engineering South China University of Technology Guangzhou510641 China

ISBN: (纸本)9789819903566

Insulated gate bipolar transistor (IGBT) has developed rapidly in recent years, and its performance is excellent in high voltage, high current and high frequency applications, which makes it been regarded as an ideal power module. However, due to the long-term operation in harsh conditions, the degradation of IGBT occurs from time to time, which will cause irreversible damage to electronic equipment and even affect the normal operation of the whole system. Therefore, it is necessary to establish a reliable IGBT anomaly detection system and apply the performance degradation prediction technology to the prediction of IGBT in the whole life cycle. In this paper, based on the data-driven method of degradation characteristic parameters, combined with grey correlation degree, Mahalanobis distance, Kalman filter, support vector regression and other methods, the performance degradation prediction of IGBT is completed and the above methods are verified and analyzed based on NASA public data. © 2023, Beijing Paike Culture Commu. Co., Ltd.

关键词： NASA

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Vector Characterization Method of Multiple Stress Acceleration Factors for High-reliability Electronic Products 14

Vector Characterization Method of Multiple Stress Accelerati...

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14th International Conference on reliability, Maintainability and Safety, ICRMS 2023

作者： Wu, Jian-Guo Yu, Rong-Gang Shi, Chang-Wei Feng, Guo-Lin Science and Technology on Reliability and Environment Engineering Laboratory Beijing Institute of Structure and Environment Engineering Beijing100076 China Beijing Institute of Structure and Environment Engineering Beijing100076 China

ISBN: (纸本)9798350329988

Accelerated life testing is one of the rapid verification methods for highly reliable electronic products in complex service environments. Existing acceleration models primarily rely on single or doable stress, making it difficult to meet the reliability improvement needs of highly reliable electronic products in terms of fault excitation efficiency and service environment simulation accuracy. This article proposes a vector representation method for the multi stress acceleration factor of highly reliable electronic products based on the random vector theory and product failure time model, considering the multi stress coupling effect in the product failure mechanism to improve the accuracy of the multi stress acceleration model when describing the product failure mechanism. The method was applied to statistically analyze the temperature, humidity, and electrical stress constant acceleration life test data of power control components under 5 different stress combinations. The predicted results of the model showed an error of less than 10% compared to the test results, verifying the scientific and feasible vector characterization of multi stress acceleration factors in highly reliable electronic products and providing a method for the research of multi stress acceleration test technology in electronic products. © 2023 IEEE.

关键词： accelerated life test acceleration model multidimensional vector multiple stresses

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Dependence of Plastic Stability on 3D Interface Layer in Nanolaminated Materials

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Acta Metallurgica Sinica(English Letters) 2022年第11期35卷 1759-1764页

作者： Shuimiao Jiang Lichen Bai Qi An Zhe Yan Weiming Li Kaisheng Ming Shijian Zheng Tianjin Key Laboratory of Materials Laminating Fabrication and Interface Control Technology School of Materials Science and EngineeringHebei Universityof TechnologyTianjin 300130China State Key Laboratory of Reliability and Intelligence of Electrical Equipment Hebei University of TechnologyTianjin 300130China

The nanolaminated materials generally exhibit poor plasticity due to the fast onset of shear *** interface structure is an eff ective approach for enhancing plasticity via postponing or suppressing the shear ***,we introduce 4 nm thick CuNb 3D amorphous interface layers and Nb 3D crystalline interface layers in Cu nanolaminated materials,*** situ micro-pillar compression tests show that samples with crystalline interface layers exhibit shear instability,while the samples with amorphous interface layers display uniform *** the plastic deformation of the singlecrystal crystalline interface layer is anisotropic,except for well-aligned slip systems,dislocations on other slip systems have a poor ability to transmit the 3D crystalline interface layer,leading to localized dislocations pileups and shear *** contrast,the amorphous interface layer which is plastically isotropic accommodates dislocations from arbitrary slip systems of the matrix,which can alleviate the stress concentrations at the interface,and thus suppresses the shear instability.

关键词： Multilayers Interface Plastic deformation Dislocation Amorphous interface

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Investigation of Off-state Stress Time-Dependent Dynamic On-resistance of Commercial High Voltage GaN HEMTs 18

Investigation of Off-state Stress Time-Dependent Dynamic On-...

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18th IEEE Conference on Industrial Electronics and Applications, ICIEA 2023

作者： Li, Yao Tang, Hui Zhang, Ke Ni, Yiqiang He, Liang He, Zhiyuan Shi, Yijun Liu, Jun University of South China School of Electrical Engineering Hengyang China Electronic Product Reliability and Environmental Testing Research Institute Science and Technology on Reliability Physics and Application of Electronic Component Laboratory Guangzhou China

ISBN: (纸本)9798350312201

The effects of off-state stress time on dynamic on-resistance are investigated in a commercial 650 V GaN power device. A modified double pulse test (DPT) circuit is used to evaluate the dynamic on-resistance degradation with various stress value and time under hard-switching conditions. Our experimental results reveal partial recovery behaviors of dynamic on-resistance with stress voltage increasing. The dynamic on-resistance degradation gets more severe as stress voltage initially increases. Then the dynamic on-resistance reaches a peak value and begins to decrease as the stress voltage further increases. Furthermore, we find that the turning point of maximum dynamic on-resistance occurs at a lower stress voltage with longer stress time. It indicates that stress time is a very important factor affecting the degree of dynamic on-resistance degradation. © 2023 IEEE.

关键词： III-V semiconductors

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Research of Travel Time reliability Evaluation Method for Road Network Considering Vehicle Coordination Under Unexpected Events

Research of Travel Time Reliability Evaluation Method for Ro...

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International Symposium on System and Software reliability (ISSSR)

作者： Baoqi He Ruiying Li School of Reliability and Systems Engineering Beihang University Beijing China Science and Technology on Reliability and Environmental Engineering Laboratory Beijing China

ISBN: (数字)9798331501242

ISBN: (纸本)9798331501259

Unexpected events can significantly affect the travel time of vehicles, however intelligent driving technology improves vehicle coordination, thereby mitigating these impacts. To evaluate the travel time reliability of road network in such scenarios, this paper designs a traffic modeling and simulation method to obtain the travel time of road section with the consideration of both unexpected events and vehicle cooperation. Based on the simulation results, a VC-BPR function is proposed to modify the traditional BPR function, and the Monte Carlo method is used to evaluate the travel time reliability of the road network. An urban road network is used as a case to demonstrate the effectiveness of this method, and the results show that the travel time reliability under unexpected events increases along with that of vehicle coordination. Notably, after the degree of vehicle coordination falls below 70%, the travel time reliability experiences a significant decline.

关键词： Monte Carlo methods Roads Simulation Fitting reliability engineering Data models Safety reliability Security

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Fault diagnosis of satellite power system based on rough K-means clustering and fuzzy multi-attribute decision making 3

Fault diagnosis of satellite power system based on rough K-m...

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3rd International Conference on Electrical engineering and Mechatronics technology, ICEEMT 2023

作者： Xing, Jingyi Wang, Feng Ma, Ke Sun, Qilong Suo, Mingliang Institute of Reliability Engineering Beihang University Beijing100191 China National Key Laboratory of Science and Technology on Reliability and Environmental Engineering Beijing100191 China Beihang University School of Reliability and Systems Engineering Beijing100191 China Beijing Institute of Space Long March Vehicle Beijing100076 China

ISBN: (纸本)9798350303698

Fault diagnosis is an integral part of a satellite characterized by high autonomy, which is one of the fundamental guarantees to ensure the normal operation of the satellite. Clustering, as an unsupervised data mining method, is widely used in fault diagnosis. Regarding fault detection and isolation with the high real-time requirements, K-means clustering becomes a typical representative of effective diagnosis tools thanks to its fast-running characteristic. However, the stiff partition idea of K-means clustering seriously affects its results, and it may even lead to misdiagnosis. Therefore, to meet the need for faster and more accurate fault diagnosis of satellite, we introduce a clustering method combined with K-means and rough set, which utilizes the imprecise description characteristic of rough set to cluster samples flexibly. Subsequently, the clustering results are fed into a multi-attribute decision making model to generate a fuzzy decision-making model for fault diagnosis. Finally, the experimental results of fault diagnosis based on a satellite power system prove the effectiveness and superiority of our method. © 2023 IEEE.

关键词： Satellites

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