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Tear proteomics reveals biomarkers for visual field progression in normal-tension glaucoma
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作者 Le-Wei Tang Hui-Yan Mao +5 位作者 Mei-Min Lin Si Zhu Qiang-Jie Huang De-Fu Chen Wei-He Zhou Yuan-Bo Liang 《International Journal of Ophthalmology(English edition)》 2026年第1期1-10,共10页
AIM:To identify early biomarkers associated with glaucomatous visual field(VF)progression in patients with normal-tension glaucoma(NTG).METHODS:This study included patients were divided into two groups based on diseas... AIM:To identify early biomarkers associated with glaucomatous visual field(VF)progression in patients with normal-tension glaucoma(NTG).METHODS:This study included patients were divided into two groups based on disease progression status.Tear samples were collected for proteomic analysis.Dataindependent acquisition(DIA)mass spectrometry combined with bioinformatic analyses was performed to identify and validate potential protein biomarkers for NTG progression.Additionally,differentially expressed proteins(DEPs)were evaluated using mediating effect models and receiver operating characteristic(ROC)curve analysis.RESULTS:A total of 19 patients(20 eyes)with NTG participated in this study,including 10 patients(4 males and 6 females;10 eyes)in the progression group with mean age of 67.70±9.03y and 10 patients(4 males and 6 females;10 eyes)in the non-progression group with mean age of 68.60±7.58y.A total of 158 significantly differentially expressed proteins were detected.UniProt database annotation identified 3 upregulated proteins and 12 downregulated proteins.Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway analysis showed that these DEPs were mainly enriched in pathways such as oocyte meiosis.Gene Ontology(GO)enrichment analysis revealed functional clusters related to cellular processes.Weighted gene coexpression network analysis(WGCNA)indicated that the core proteins were primarily involved in the neurodegenerationmultiple diseases pathway and cellular processes.Mediating effect analysis identified PRDX4(L)as a potential protein biomarker.ROC curve analysis showed that GNAI1 had the largest area under the curve(AUC=0.889).CONCLUSION:This study identifies 15 differentially expressed proteins in the tear fluid of NTG patients,including PRDX4(L).PRDX4(L)plays a key role in oxidative stress. 展开更多
关键词 normal-tension glaucoma TEARS PROTEOMICS biomarkers visual field progression
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Ultrasound/magnetic field dual-responsive Fe_(3)O_(4)/glucose oxidase catalytic microbubbles for enhanced bacterial biofilm elimination
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作者 Chi Zhang Dou Wang +6 位作者 Liang Lu Feng-Jiao Xu Fan-Sen Xu Xuan Wu Xiao-Xiao Xu Xiao Li Li-Hui Yuwen 《Biomedical Engineering Communications》 2026年第1期4-12,共9页
Background:The bacterial biofilm poses a significant challenge to traditional antibiotic therapy.There is a great need to develop novel antibiofilm agents combined with biofilm disrupting and bacteria-killing without ... Background:The bacterial biofilm poses a significant challenge to traditional antibiotic therapy.There is a great need to develop novel antibiofilm agents combined with biofilm disrupting and bacteria-killing without the dependence of antibiotic.Methods:Herein,we prepared ultrasound/magnetic field-responsive ferroferric oxide nanoparticles(Fe_(3)O_(4))/glucose oxidase microbubbles(FGMB)to form a cascade catalytic system for effective removing methicillin-resistant Staphylococcus aureus biofilms.FGMB were prepared through interfacial self-assembly of Fe_(3)O_(4) nanoparticles(NPs)and glucose oxidase(GOx)at the gas-liquid interface stabilized by surfactants.Under ultrasound/magnetic field stimulation,FGMB disrupted biofilm architecture through microbubble collapse-induced microjets and magnetically driven displacement.Simultaneously,ultrasound-triggered rupture of FGMB released GOx and Fe_(3)O_(4) NPs.Glucose can be oxidized by GOx to generate gluconic acid and hydrogen peroxide which was subsequently catalyzed into hydroxyl radicals by Fe_(3)O_(4) NPs,enabling chemical eradication of biofilm-embedded bacteria.Results:Optical microscopy images demonstrated that FGMB have spherical structure with average size of approximately 17μm.FGMB showed a 65.4%decrease in methicillin-resistant Staphylococcus aureus biofilm biomass and 1.1 log bacterial inactivation efficiency(91.2%),suggesting effective biofilm elimination.In vitro experimental results also indicate that FGMB have good biocompatibility.Conclusion:This antibiofilm strategy integrated dual modes of physical biofilm disruption with chemical bacteria-killing shows great potential as a versatile,non-resistant strategy for bacterial biofilm elimination. 展开更多
关键词 bacterial biofilm ULTRASOUND magnetic field catalytic microbubbles mechanical disruption chemical degradation
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Electric-Field-Driven Generative Nanoimprinting for Tilted Metasurface Nanostructures
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作者 Yu Fan Chunhui Wang +6 位作者 Hongmiao Tian Xiaoming Chen Ben QLi Zhaomin Wang Xiangming Li Xiaoliang Chen Jinyou Shao 《Nano-Micro Letters》 2026年第1期290-305,共16页
Tilted metasurface nanostructures,with excellent physical properties and enormous application potential,pose an urgent need for manufacturing methods.Here,electric-field-driven generative-nanoimprinting technique is p... Tilted metasurface nanostructures,with excellent physical properties and enormous application potential,pose an urgent need for manufacturing methods.Here,electric-field-driven generative-nanoimprinting technique is proposed.The electric field applied between the template and the substrate drives the contact,tilting,filling,and holding processes.By accurately controlling the introduced included angle between the flexible template and the substrate,tilted nanostructures with a controllable angle are imprinted onto the substrate,although they are vertical on the template.By flexibly adjusting the electric field intensity and the included angle,large-area uniform-tilted,gradient-tilted,and high-angle-tilted nanostructures are fabricated.In contrast to traditional replication,the morphology of the nanoimprinting structure is extended to customized control.This work provides a cost-effective,efficient,and versatile technology for the fabrication of various large-area tilted metasurface structures.As an illustration,a tilted nanograting with a high coupling efficiency is fabricated and integrated into augmented reality displays,demonstrating superior imaging quality. 展开更多
关键词 Generative nanoimprinting Electric field assistance Tilted metasurface structures Large-area fabrication
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Visual field prediction using K-means clustering in patients with primary open angle glaucoma
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作者 Junyoung Lee Jihun Kim +5 位作者 Hwayoung Kim Sangwoo Moon EunAh Kim Sanghun Jeong Hojin Yang Jiwoong Lee 《International Journal of Ophthalmology(English edition)》 2026年第1期63-68,共6页
AIM:To evaluate long-term visual field(VF)prediction using K-means clustering in patients with primary open angle glaucoma(POAG).METHODS:Patients who underwent 24-2 VF tests≥10 were included in this study.Using 52 to... AIM:To evaluate long-term visual field(VF)prediction using K-means clustering in patients with primary open angle glaucoma(POAG).METHODS:Patients who underwent 24-2 VF tests≥10 were included in this study.Using 52 total deviation values(TDVs)from the first 10 VF tests of the training dataset,VF points were clustered into several regions using the hierarchical ordered partitioning and collapsing hybrid(HOPACH)and K-means clustering.Based on the clustering results,a linear regression analysis was applied to each clustered region of the testing dataset to predict the TDVs of the 10th VF test.Three to nine VF tests were used to predict the 10th VF test,and the prediction errors(root mean square error,RMSE)of each clustering method and pointwise linear regression(PLR)were compared.RESULTS:The training group consisted of 228 patients(mean age,54.20±14.38y;123 males and 105 females),and the testing group included 81 patients(mean age,54.88±15.22y;43 males and 38 females).All subjects were diagnosed with POAG.Fifty-two VF points were clustered into 11 and nine regions using HOPACH and K-means clustering,respectively.K-means clustering had a lower prediction error than PLR when n=1:3 and 1:4(both P≤0.003).The prediction errors of K-means clustering were lower than those of HOPACH in all sections(n=1:4 to 1:9;all P≤0.011),except for n=1:3(P=0.680).PLR outperformed K-means clustering only when n=1:8 and 1:9(both P≤0.020).CONCLUSION:K-means clustering can predict longterm VF test results more accurately in patients with POAG with limited VF data. 展开更多
关键词 K-means clustering hierarchical ordered partitioning and collapsing hybrid pointwise linear regression visual field prediction
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GAF结合卷积神经网络的滚动轴承故障诊断研究 被引量:1
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作者 张文兴 陈豪 +1 位作者 刘文婧 王建国 《机械设计与制造》 北大核心 2025年第5期12-17,共6页
为了充分发挥深度卷积神经网络识别二维图片在轴承故障诊断过程中的优势,这里提出了一种改进的格拉姆角场,改进后的算法在生成图片后具有更多的特征,经验证其在神经网络训练中收敛速度更快。其次结合改进的CNN模型,改进后的模型引进深... 为了充分发挥深度卷积神经网络识别二维图片在轴承故障诊断过程中的优势,这里提出了一种改进的格拉姆角场,改进后的算法在生成图片后具有更多的特征,经验证其在神经网络训练中收敛速度更快。其次结合改进的CNN模型,改进后的模型引进深度卷积结合注意力机制,保证模型在实现更少模型参数和更快的推理速度同时,在验证集能够取得更高的准确率。试验和研究结果表明,该图片编码方式结合改进的神经网络,在模型收敛上更迅速,并且在验证集上具有更好的准确率和鲁棒性。 展开更多
关键词 格拉姆角场 故障诊断 深度学习 神经网络
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Absorbed Dose to Water Rate in a Cyberknife VSI System Reference Field Using Ionization Chambers and Gafchromic Films
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作者 Guerda Massillon-JL Nestor Aragó +4 位作者 n-Martí nez Arnulfo Gó mez-Muñ oz 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2017年第1期80-92,共13页
This work investigated the absorbed dose to water rate under reference conditions in a Cyberknife VSI system using radiochromic films EBT3 and MD-V3 and three ionization chambers: an Exradin A12 and two FC65P Welh&... This work investigated the absorbed dose to water rate under reference conditions in a Cyberknife VSI system using radiochromic films EBT3 and MD-V3 and three ionization chambers: an Exradin A12 and two FC65P Welh&ouml;fer Scanditronix with different serial numbers. The correction factor,, was studied using a Varian iX linac and the Cyberknife system. The measurements in the Varian iX were performed in a 10 × 10 cm2 field, 10 cm depth in liquid water at 90 cm and 70 cm SSD and in a 5.4 × 5.4 cm2 field, 10 cm depth at 70 cm SSD to simulate the Cyberknife conditions. In the Cyberknife system, measurements were performed using ionization chambers and both film types at 70 cm SSD and 10 cm depth in its 6 cm diameter reference field. The results indicate that ?is independent of the dosimeters and the evaluation methods. Maximum differences of 0.22% - 0.55% (combined uncertainties of 1.22% - 1.98%, k = 1) are obtained on ?using Varian iX, whereas discrepancies of 2.08% - 2.09% (combined uncertainties of 1.87% - 2.13%, k = 1) are observed using the Cyberknife system. Given the agreement between detectors and the combined standard uncertainties, the data from Varian iX could be considered the most accurate and consequently a weighted average factor of 0.902 ± 0.006 could be used for the Cyberknife VSI system reference field. Within measurement uncertainties, the absorbed dose rate measured in the Cyberknife VSI system reference field was found to be independent of the dosimeters used. These results suggest that the absorbed dose measured at a point within a given field size should be the same, regardless the dosimeter used, if their dosimetric characteristics are well known. This highlighted the importance of performing dosimetry by controlling all parameters that could affect the dosimeter response. One can conclude that radiochromic film dosimetry can be considered as an appropriate alternative for measuring absorbed dose to water rate. 展开更多
关键词 Small field DOSIMETRY Reference field CYBERKNIFE gafchromic Films Ionization CHAMBERS Dose RATE EBT3 MD-V3 6 MV X-Rays
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Influence of different data selection criteria on internal geomagnetic field modeling 被引量:4
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作者 HongBo Yao JuYuan Xu +3 位作者 Yi Jiang Qing Yan Liang Yin PengFei Liu 《Earth and Planetary Physics》 2025年第3期541-549,共9页
Earth’s internal core and crustal magnetic fields,as measured by geomagnetic satellites like MSS-1(Macao Science Satellite-1)and Swarm,are vital for understanding core dynamics and tectonic evolution.To model these i... Earth’s internal core and crustal magnetic fields,as measured by geomagnetic satellites like MSS-1(Macao Science Satellite-1)and Swarm,are vital for understanding core dynamics and tectonic evolution.To model these internal magnetic fields accurately,data selection based on specific criteria is often employed to minimize the influence of rapidly changing current systems in the ionosphere and magnetosphere.However,the quantitative impact of various data selection criteria on internal geomagnetic field modeling is not well understood.This study aims to address this issue and provide a reference for constructing and applying geomagnetic field models.First,we collect the latest MSS-1 and Swarm satellite magnetic data and summarize widely used data selection criteria in geomagnetic field modeling.Second,we briefly describe the method to co-estimate the core,crustal,and large-scale magnetospheric fields using satellite magnetic data.Finally,we conduct a series of field modeling experiments with different data selection criteria to quantitatively estimate their influence.Our numerical experiments confirm that without selecting data from dark regions and geomagnetically quiet times,the resulting internal field differences at the Earth’s surface can range from tens to hundreds of nanotesla(nT).Additionally,we find that the uncertainties introduced into field models by different data selection criteria are significantly larger than the measurement accuracy of modern geomagnetic satellites.These uncertainties should be considered when utilizing constructed magnetic field models for scientific research and applications. 展开更多
关键词 Macao Science Satellite-1 SWARM geomagnetic field modeling data selection core field crustal field
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基于VMD-GAF-MCNN的多传感融合海缆裸露状态识别 被引量:1
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作者 王伟 汪文东 +3 位作者 游鹏 肖泽鑫 安博文 崔桂艳 《光通信研究》 北大核心 2025年第3期90-97,共8页
【目的】桩基冲刷及海缆登陆段的冲刷监测常采用多波束(侧扫)声呐方法进行扫描测量,根据扫测图像评判冲刷程度,但该方法缺乏实时性,仅在运维时间才获取相关数据。目前海缆冲刷监测常采用温度和振动分析,但现场采集的分布式光纤传感信号... 【目的】桩基冲刷及海缆登陆段的冲刷监测常采用多波束(侧扫)声呐方法进行扫描测量,根据扫测图像评判冲刷程度,但该方法缺乏实时性,仅在运维时间才获取相关数据。目前海缆冲刷监测常采用温度和振动分析,但现场采集的分布式光纤传感信号具有非平稳、非线性且易受噪声干扰的特点,同时存在单一传感器提取特征信息不完备的问题,文章提出了一种基于优化变分模态分解(VMD)、格拉姆角场(GAF)和多尺度卷积神经网络(MCNN)的多传感融合海缆裸露状态识别方法,提高了登陆段海缆裸露状态识别的准确率。【方法】文章所提优化VMD-GAF-MCNN使用信号处理和深度学习的方法实现。首先,提出一种基于希尔伯特变换(HT)计算包络峰度最大值的VMD模数优化方法,利用优化VMD对分布式光纤传感信号进行分解,并利用相关系数法筛选本征模态分量(IMF),提取各阶IMF与原始信号相关系数最大的IMF分量;其次,提出一种GAF二维图像编码方法,利用GAF将分布式光纤测温系统(DTS)和分布式光纤声学传感系统(DAS)采集的光纤温度和振动信号筛选出的IMF分量编码成二维图像;最后,设计MCNN结构,随机划分训练集和测试集,将训练集输入网络进行训练,测试集验证网络的有效性,实现海缆裸露状态识别。【结果】利用现场采集的海缆光纤温度和振动数据进行验证,测试准确率达到99.85%,相较于单一传感器分别提高了0.95%和0.85%。【结论】文章所提方法能够准确识别登陆段海缆裸露状态,为制定海缆运维策略提供技术支撑。 展开更多
关键词 模式识别 多传感融合 优化变分模态分解 格拉姆角场 多尺度卷积神经网络
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基于VGAF与混合时序网络的电缆故障诊断方法
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作者 李练兵 代亮亮 +1 位作者 高国强 王磊 《华中科技大学学报(自然科学版)》 北大核心 2025年第7期16-23,共8页
构建一种基于变分模态分解格拉姆角场(VGAF)和混合卷积时序网络算法(CLT)的电缆故障诊断方法.首先,通过变分模态分解(VMD)优化输入格拉姆角场(GAF)中的历史故障数据,根据中心频率和阈值β剔除虚假分量;然后,利用GAF将优化后的数据归一... 构建一种基于变分模态分解格拉姆角场(VGAF)和混合卷积时序网络算法(CLT)的电缆故障诊断方法.首先,通过变分模态分解(VMD)优化输入格拉姆角场(GAF)中的历史故障数据,根据中心频率和阈值β剔除虚假分量;然后,利用GAF将优化后的数据归一化处理转换为二维特征图,选择多特征信息输入到CLT网络;最后,在混合时序网络中输出预测值、评价指标λ_(1)和λ_(2),在模型中评估网络的诊断精度.最后,利用算例数据验证所提组合模型在同类型故障下平均绝对误差(MAE)、均方根误差(RMSE)、平均绝对百分比误差(MAPE)可分别降低20.33%,36.79%及10.12%,决定系数R2可提高0.11%. 展开更多
关键词 电缆智能诊断 优化格拉姆角场 混合卷积时序网络 特征提取
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Establishment of a field visualization detection method for multiplex recombinase polymerase amplification combined with CRISPR/Cas12a in genetically modified crops 被引量:2
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作者 YAN Jingying NI Liang +2 位作者 SHEN Xingyu LÜ Bingtao LI Yu 《浙江大学学报(农业与生命科学版)》 北大核心 2025年第3期391-401,共11页
With the approval of more and more genetically modified(GM)crops in our country,GM safety management has become more important.Transgenic detection is a major approach for transgenic safety management.Nevertheless,a c... With the approval of more and more genetically modified(GM)crops in our country,GM safety management has become more important.Transgenic detection is a major approach for transgenic safety management.Nevertheless,a convenient and visual technique with low equipment requirements and high sensitivity for the field detection of GM plants is still lacking.On the basis of the existing recombinase polymerase amplification(RPA)technique,we developed a multiplex RPA(multi-RPA)method that can simultaneously detect three transgenic elements,including the cauliflower mosaic virus 35S gene(CaMV35S)promoter,neomycin phosphotransferaseⅡgene(NptⅡ)and hygromycin B phosphotransferase gene(Hyg),thus improving the detection rate.Moreover,we coupled this multi-RPA technique with the CRISPR/Cas12a reporter system,which enabled the detection results to be clearly observed by naked eyes under ultraviolet(UV)light(254 nm;which could be achieved by a portable UV flashlight),therefore establishing a multi-RPA visual detection technique.Compared with the traditional test strip detection method,this multi-RPA-CRISPR/Cas12a technique has the higher specificity,higher sensitivity,wider application range and lower cost.Compared with other polymerase chain reaction(PCR)techniques,it also has the advantages of low equipment requirements and visualization,making it a potentially feasible method for the field detection of GM plants. 展开更多
关键词 genetically modified crop recombinase polymerase amplification CRISPR/Cas12a field detection
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Fault diagnosis of three-phase inverter based on GAF-CNN
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作者 DONG Weiguang LU Haobo LI Shengchang 《Journal of Measurement Science and Instrumentation》 2025年第3期456-463,共8页
To apply the advantages of deep learning in recognizing two-dimensional(2D)images to three-phase inverter fault diagnosis,a threephase inverter fault diagnosis model based on gramian angular field(GAF)combined with co... To apply the advantages of deep learning in recognizing two-dimensional(2D)images to three-phase inverter fault diagnosis,a threephase inverter fault diagnosis model based on gramian angular field(GAF)combined with convolutional neural network(CNN)was proposed.Since the current signals of the inverter in different working states are different,the images formed by the time series encoding are also different,which enables the image recognition technology to be used for time series classification to identify the fault current signal of the inverter.Firstly,the one-dimensional(1D)inverter fault current signal was converted into a 2D image through the GAF.Next,the CNN model suitable for inverter fault diagnosis was input to realize the detection,classification and location of inverter fault.The simulation results show that the recognition accuracy of this method is 99.36%under different noisy data.Compared with other traditional methods,it has higher accuracy and reliability,and stronger anti-noise interference capability and robustness in dealing with noisy data.Therefore,it is an effective fault diagnosis method for inverters. 展开更多
关键词 fault diagnosis gramian angular field(gaf) convolutional neural network(CNN) anti-noise interference ROBUSTNESS
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Preliminary results suggest observations from Macao Science Satellite-1 system can improve knowledge of tidal-induced magnetic fields 被引量:8
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作者 ZhengYong Ren YiPiao Huang +2 位作者 Cong Yang ChaoJian Chen Keke Zhang 《Earth and Planetary Physics》 2025年第3期586-594,共9页
This study presents preliminary results of tidal-induced magnetic field signals extracted from 9 months of data collected by the Macao Science Satellite-1(MSS-1) from November 2023 to July 2024. Tidal signals were iso... This study presents preliminary results of tidal-induced magnetic field signals extracted from 9 months of data collected by the Macao Science Satellite-1(MSS-1) from November 2023 to July 2024. Tidal signals were isolated using sequential modeling techniques by subtracting non-tidal field model predictions from observed magnetic data. The extracted MSS-1 results show strong agreement with those from the Swarm and CryoSat satellites. MSS-1 effectively captures key large-scale tidal-induced magnetic anomalies, mainly due to its unique 41-degree low-inclination orbit, which provides wide coverage of local times. This finding underscores the strong potential of MSS-1 to recover high-resolution global tidal magnetic field models as more MSS-1 data become available. 展开更多
关键词 Macao Science Satellite-1 satellite magnetic data tidal-induced magnetic fields
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基于GAF与Swin Transformer的逆变器故障诊断 被引量:1
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作者 杨龙欢 董效杰 +2 位作者 王一帆 刘承毅 周运磊 《通信与信息技术》 2025年第2期98-103,共6页
逆变器故障会降低电站的发电效率和稳定性。针对逆变器的故障诊断,以带LCL型滤波器的并网逆变器为研究对象,详细介绍了逆变器的结构和数学模型,归纳和整理了光伏逆变器常见的故障种类及其特点;使用仿真平台搭建光伏并网逆变器模型,对逆... 逆变器故障会降低电站的发电效率和稳定性。针对逆变器的故障诊断,以带LCL型滤波器的并网逆变器为研究对象,详细介绍了逆变器的结构和数学模型,归纳和整理了光伏逆变器常见的故障种类及其特点;使用仿真平台搭建光伏并网逆变器模型,对逆变器故障中最易发生的逆变器开关管(IGBT)开路故障进行仿真模拟,采集一维故障电流信号;利用格拉姆角场(GAF)将一维时间序列故障数据进行变换,得到二维图像。基于卷积神经网络在图像处理上的优势,提出了基于格拉姆角场与Swin Transformer的故障诊断模型。该故障诊断模型经过迭代训练优化模型参数后,在不同噪声比的样本上进行测试。结果表明,故障诊断准确率达到96.81%,证明了故障诊断模型的有效性和抗噪能力。 展开更多
关键词 并网逆变器 格拉姆角场 Swim Transformer
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基于GAF和SE-ResNeXt的滚动轴承故障诊断方法 被引量:1
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作者 赵国威 曾静 《机械设计与制造工程》 2025年第2期63-67,共5页
为了解决滚动轴承故障诊断中不能有效提取信号特征导致准确率低以及随着网络层数加深卷积神经网络出现网络退化的问题,提出了一种基于格拉姆角场(GAF)与Squeeze-and-Excitation-ResNeXt(SE-ResNeXt)网络的滚动轴承故障诊断方法。对一维... 为了解决滚动轴承故障诊断中不能有效提取信号特征导致准确率低以及随着网络层数加深卷积神经网络出现网络退化的问题,提出了一种基于格拉姆角场(GAF)与Squeeze-and-Excitation-ResNeXt(SE-ResNeXt)网络的滚动轴承故障诊断方法。对一维轴承振动信号进行重叠采样后使用PAA将其调整为合适的长度,通过GAF转换为二维图像作为输入,保存原数据的特征与时序相关性;选择ResNeXt模型并加入SE模块,将二维图像输入该模型实现对故障特征的自适应提取和分类,最终实现故障诊断。仿真实验结果表明,该方法能够有效提取故障特征,进行故障诊断并具有较强的鲁棒性,故障诊断准确率为99.77%,在信噪比为10 dB的环境下故障诊断准确率为95.87%。 展开更多
关键词 故障诊断 滚动轴承 格拉姆角场 SE-ResNeXt
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Fast and Accurate Prediction of Electromagnetic and Temperature Fields for SPMSM Equipped with Unequally Thick Magnetic Poles 被引量:2
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作者 Feng Liu Xiuhe Wang +1 位作者 Lingling Sun Hongye Wei 《CES Transactions on Electrical Machines and Systems》 2025年第2期199-211,共13页
With the continuous upgrading of traditional manufacturing industries and the rapid rise of emerging technology fields,the performance requirements for the permanent magnet synchronous motors(PMSMs)have become higher ... With the continuous upgrading of traditional manufacturing industries and the rapid rise of emerging technology fields,the performance requirements for the permanent magnet synchronous motors(PMSMs)have become higher and higher.The importance of fast and accurate electromagnetic thermal coupling analysis of such motors becomes more and more prominent.In view of this,the surfacemounted PMSM(SPMSM)equipped with unequally thick magnetic poles is taken as the main object and its electromagnetic thermal coupling analytical model(ETc AM)is investigated.First,the electromagnetic analytical model(EAM)is studied based on the modified subdomain method.It realizes the fast calculation of key electromagnetic characteristics.Subsequently,the 3D thermal analytical model(TAM)is developed by combining the EAM,the lumped parameter thermal network method(LPTNM),and the partial differential equation of heat flux.It realizes the fast calculation of key thermal characteristics in 3D space.Further,the information transfer channel between EAM and TAM is built with reference to the intrinsic connection between electromagnetic field and temperature field.Thereby,the novel ETcAM is proposed to realize the fast and accurate prediction of electromagnetic and temperature fields.Besides,ETcAM has a lot to commend it.One is that it well accounts for the complex structure,saturation,and heat exchange behavior.Second,it saves a lot of computer resources.It offers boundless possibilities for initial design,scheme evaluation,and optimization of motors.Finally,the validity,accuracy,and practicality of this study are verified by simulation and experiment. 展开更多
关键词 Electromagnetic field and temperature field Electromagnetic thermal coupling analytical model(ETcAM) Fast and accurate prediction SPMSM Unequally thick magnetic poles
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High-burn-up structure evolution in polycrystalline UO_(2):Phase-field modeling investigation 被引量:2
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作者 Dan Sun Yanbo Jiang +4 位作者 Chuanbao Tang Yong Xin Zhipeng Sun Wenbo Liu Yuanming Li 《Chinese Physics B》 2025年第2期378-386,共9页
Understanding the evolution of microstructures in nuclear fuels under high-burn-up conditions is critical for extending fuel refueling cycles and enhancing nuclear reactor safety.In this study,a phase-field model is p... Understanding the evolution of microstructures in nuclear fuels under high-burn-up conditions is critical for extending fuel refueling cycles and enhancing nuclear reactor safety.In this study,a phase-field model is proposed to examine the evolution of high-burn-up structures in polycrystalline UO_(2).The formation and growth of recrystallized grains were initially investigated.It was demonstrated that recrystallization kinetics adhere to the Kolmogorov–Johnson–Mehl–Avrami(KJMA)equation,and that recrystallization represents a process of free-energy reduction.Subsequently,the microstructural evolution in UO_(2) was analyzed as the burn up increased.Gas bubbles acted as additional nucleation sites,thereby augmenting the recrystallization kinetics,whereas the presence of recrystallized grains accelerated bubble growth by increasing the number of grain boundaries.The observed variations in the recrystallization kinetics and porosity with burn-up closely align with experimental findings.Furthermore,the influence of grain size on microstructure evolution was investigated.Larger grain sizes were found to decrease porosity and the occurrence of high-burn-up structures. 展开更多
关键词 high-burn-up structure phase field uranium dioxide gas bubble RECRYSTALLIZATION
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基于GAF-CNN的船用空压机故障噪声诊断方法
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作者 董明 崔德馨 李祥林 《船舶》 2025年第1期106-114,共9页
船用空压机工作环境恶劣,内外激励源众多,采集的噪声信号具有强烈的时变性,会导致故障诊断精度较低,难以实现船用空压机各类故障的有效识别。为此,该文提出将格拉姆角场(Gramian angular field,GAF)编码和卷积神经网络(convolutional ne... 船用空压机工作环境恶劣,内外激励源众多,采集的噪声信号具有强烈的时变性,会导致故障诊断精度较低,难以实现船用空压机各类故障的有效识别。为此,该文提出将格拉姆角场(Gramian angular field,GAF)编码和卷积神经网络(convolutional neural network,CNN)法相结合的故障诊断方法。首先,阐述了GAF和CNN的基本原理、方法和实施步骤;然后,通过试验模拟了船用空压机的各类故障,并采集相应噪声信号,再利用GAF将一维时域信号转换为二维图像,将特征信息映射为二维图像的颜色、点等纹理特征;最后,将二维图像输入至CNN中进行特征提取和故障诊断。试验结果表明:在保证运行效率的前提下,该方法能够有效识别船用空压机的各类故障,诊断精度达到99.2%,优于其他算法,可为船舶故障智能诊断的应用提供了新途径和新思路。 展开更多
关键词 船用空压机 噪声分析 格拉姆角场 卷积神经网络 故障诊断
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A multisource geomagnetic field model incorporating ocean circulation-induced magnetic field 被引量:5
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作者 HongBo Yao JuYuan Xu +2 位作者 Cong Yang ZhengYong Ren Keke Zhang 《Earth and Planetary Physics》 2025年第3期550-563,共14页
The movement of global ocean circulation in the Earth’s main magnetic field generates a measurable induced magnetic field(about 2 nT at geomagnetic satellite altitudes).However,this ocean circulation-induced magnetic... The movement of global ocean circulation in the Earth’s main magnetic field generates a measurable induced magnetic field(about 2 nT at geomagnetic satellite altitudes).However,this ocean circulation-induced magnetic field has not been previously estimated or incorporated into geomagnetic field models,potentially causing leakage into the core field model.Here,we present a method to account for the circulation-induced magnetic field during geomagnetic field modeling.First,a forward model of the circulation-induced magnetic field is constructed by numerically solving electromagnetic induction equations based on a realistic ocean circulation model.Then,this forward model is subtracted from the observed data.Finally,the core and lithospheric fields,magnetospheric and Earth’s mantle-induced fields,and the ocean tide-induced magnetic field are co-estimated.Applying our method to over 20 years of MSS-1,Swarm,CryoSat-2,and CHAMP satellite magnetic data,we derive a new multisource geomagnetic field model(MGFM).We find that incorporating a forward model of the circulation-induced magnetic field marginally improves the fit to the data.Furthermore,we demonstrate that neglecting the circulation-induced magnetic field in geomagnetic field modeling results in leakage into the core field model.The highlights of the MGFM model include:(i)a good agreement with the widely used CHAOS model series;(ii)the incorporation of magnetic fields induced by both ocean tides and circulation;and(iii)the suppression of leakage of the circulation-induced magnetic field into the core field model. 展开更多
关键词 Macao Science Satellite-1(MSS-1) geomagnetic field modeling ocean tides ocean circulation
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Newly Discovered High-Sulfidation Mineralization in the Yueyang Silver-Polymetallic Deposit,Zijinshan Ore Field,and Implications for Mineral Exploration 被引量:1
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作者 Jieyi Li Wenyuan Liu +4 位作者 Hua Long Jingwen Chen Jianhuan Qiu Xiaodan Lai Guiqing Xie 《Journal of Earth Science》 2025年第3期1309-1314,共6页
The Zijinshan ore field located in southwestern Fujian Province,China,is a representative porphyry-epithermal ore system hosting diverse mineralization types(Mao et al.,2013).The ore field comprises of the Zijinshan h... The Zijinshan ore field located in southwestern Fujian Province,China,is a representative porphyry-epithermal ore system hosting diverse mineralization types(Mao et al.,2013).The ore field comprises of the Zijinshan highsulfidation Cu-Au deposit,the Luoboling porphyry Cu-Mo deposit,the transitional style Cu deposit(Longjiangting and Wuziqilong)and the Yueyang low-sulfidation Agpolymetallic deposit(Zhang,2013;Zhang et al.,2003) 展开更多
关键词 transitional style cu high sulfidation mineralization Zijinshan ore field Yueyang silver polymetallic deposit porphyry epithermal ore system ore field mineral exploration diverse mineralization types
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A 100-degree lithospheric magnetic field model constructed using MSS-1,Swarm-A,and CHAMP satellite data 被引量:1
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作者 JiaXuan Zhang Yan Feng +3 位作者 Pan Zhang YuXuan Lin XinWu Li Ya Huang 《Earth and Planetary Physics》 2025年第3期667-676,共10页
By combining data from the Challenging Minisatellite Payload(CHAMP),Swarm-A,and newest Macao Science Satellite-1(MSS-1) missions,we constructed a lithospheric magnetic field model up to spherical harmonic degree N = 1... By combining data from the Challenging Minisatellite Payload(CHAMP),Swarm-A,and newest Macao Science Satellite-1(MSS-1) missions,we constructed a lithospheric magnetic field model up to spherical harmonic degree N = 100.To isolate the lithospheric magnetic field signals,we utilized the latest CHAOS-8(CHAMP,Φrsted,and SAC-C 8) model and MGFM(Multisource Geomagnetic Field Model) to remove nonlithospheric sources,including the core field,magnetospheric field,ocean tidal field,and ocean circulation field.Subsequently,orbit-by-orbit processing was applied to both scalar and vector data,such as spherical harmonic high-pass filtering,singular spectrum analysis,and line leveling,to suppress noise and residual signals along the satellite tracks.With an orbital inclination of only 41°,MSS-1 effectively captures fine-scale lithospheric magnetic field signals in mid-to low-latitude regions.Its data exhibit a root mean square error of only 0.77 nT relative to the final model,confirming the high quality and utility of lithospheric field modeling.The resulting model exhibits excellent consistency with the MF7(Magnetic Field Model 7),maintaining a high correlation up to N = 90 and still exceeding 0.65 at N = 100.These results demonstrate the reliability and value of MSS-1 data in global lithospheric magnetic field modeling. 展开更多
关键词 lithospheric magnetic field Macao Science Satellite-1(MSS-1) line leveling Magnetic field Model 7(MF7) singular spectrum analysis
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