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基于ICEEMDAN-GCNII的柱塞泵故障诊断方法研究

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液压气动与密封 2024年第6期44卷 21-29页

作者：杨喜旺山西电子科技学院山西临汾041000

为识别出柱塞泵的不同故障模式,提出一种柱塞泵故障诊断方法。首先,将柱塞泵的振动加速度信号数据通过改进的自适应噪声完备集成经验模态分解(Improved Complete Ensemble Empirical Mode Decomposition with Adaptive Noise,ICEEMDAN)... 详细信息

为识别出柱塞泵的不同故障模式,提出一种柱塞泵故障诊断方法。首先,将柱塞泵的振动加速度信号数据通过改进的自适应噪声完备集成经验模态分解(Improved Complete Ensemble Empirical Mode Decomposition with Adaptive Noise,ICEEMDAN)方法分解为多个固有模态分量(Intrinsic Mode Function,IMF),分别计算筛选后的IMF分量的时域、频域特征并拼接为特征向量;其次,使用K近邻算法计算各特征向量之间的相似度,依据相似度生成一种故障样本特征图,实现一维时序数据到图结构数据的转换,刻画不同故障样本之间的联系;最后,将故障样本特征图输入至基于初始残差和恒等映射的图卷积网络(Graph Convolutional Network via Initial Residual and Identity Mapping,GCNII)诊断模型中,准确的识别出柱塞泵的不同故障类型。经实验验证,该方法在5种柱塞泵故障类型上的诊断率达到了98.67%。

关键词：柱塞泵 ICEEMDAN GCNII 故障诊断

基于激光雷达回波信号的雾天船舶航线快速辨识

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舰船科学技术 2024年第6期46卷 135-139页

作者：杨喜旺黄晋英中北大学大数据学院山西太原030051 中北大学机械工程学院山西太原030051

激光雷达所处环境噪声较大,船舶航线辨识困难,为解决该问题,提出基于激光雷达回波信号的雾天船舶航线快速辨识方法。采用信号累积增强算法增强雾天激光雷达回波信号,利用改进经验模态分解算法去噪处理增强后的回波信号,结合回波信号通... 详细信息

激光雷达所处环境噪声较大,船舶航线辨识困难,为解决该问题,提出基于激光雷达回波信号的雾天船舶航线快速辨识方法。采用信号累积增强算法增强雾天激光雷达回波信号,利用改进经验模态分解算法去噪处理增强后的回波信号,结合回波信号通过最小类内方差获取得到船舶航线和水面最佳分割阈值,提取船舶航线特征点。利用最小二乘法拟合法拟合船舶航线特征点,完成雾天船舶航线辨识。实验结果表明,所提方法应用后激光雷达回波信号更平滑,输出信噪比更高,均方根误差更低,船舶航线辨识准确率更理想。

关键词：激光雷达回波信号船舶航线辨识回波信号累积增强经验模态分解特征提取

Design and performance of a high-speed and low-noise preamplifier for SiPM

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Nuclear Science and Techniques 2023年第11期34卷 93-102页

作者： xi‑yang wang Hong‑Yu Zhang De‑Qing Fang Wan‑Bing He xiao‑Long wang Qi‑Bin Zheng Shi‑Ming Zou Key Laboratory of Nuclear Physics and Ion‑beam Application(MOE)and Institute of Modern Physics Fudan UniversityShanghai 200433China Shanghai Research Center for Theoretical Nuclear Physics NSFC and Fudan UniversityShanghai 200438China Laboratory of Radiation Detection and Medical Imaging and School of Health Science and Engineering University of Shanghai for Science and TechnologyShanghai 200093China

Considering the R&D for upgrading the K^(0)_(L) andμdetectors in the Belle II experiment using a scintillator and silicon pho-tomultiplier(SiPM),we designed a compact high-speed and low-noise *** preamplifier demonstrated a good gain stability,bandwidth of 426 MHz,baseline noise level ofσ≈0.6 mV,dynamic range of up to170 mV of the input signal amplitude,good time resolution of 20 ps,and it can be comprehensively applied to *** pole-zero-cancelation in the preamplifier reduces both the rise and fall times of the SiPM signal,which can significantly improve the time resolution and reduce the pile-up when using a large SiPM or an array of *** combinations of the preamplifier and several types of SiPMs demonstrated time resolutions better than 50 ps for most cases;when the number of detected photons was larger than 60,a time resolution of approximately 25 ps was achieved.

关键词： Silicon photomultiplier High-speed amplifier Low noise High time resolution

Cushioning Performance of a Novel Polyurethane Foam Material Applied in Fragile Packaging

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Acta Mechanica Solida Sinica 2024年第3期37卷 487-497页

作者： Huifeng xi Chunqiu Guo Jinbiao yang xiaogang wang Bowei wang Shiqing Huang Zhiwei wang School of Mechanics and Construction Engineering Jinan UniversityGuangzhou510632China College of Packing Engineering Jinan UniversityZhuhai519070China MOE Key Lab of Disaster Forecast and Control in Engineering Jinan UniversityGuangzhou510632China Foshan Soft Valley Technology Co. Ltd.Foshan528000China

For fragile products,packaging requires cushioning protection to prevent irreversible damage from accidental falls,transportation impacts,and other *** new polyurethane foam(PUF)material demonstrates superior cushioning and vibration isolation performance in practical applications,effectively minimizing damage from *** and vibration experiments were conducted on packages comprising novel PUF,expandable polyethylene,ethylene-vinyl acetate copolymer foam,and *** verify that the new PUF material outperforms in cushioning and vibration isolation,as observed from the acceleration ***,a random vibration analysis of a packaging unit involving different thicknesses of PUF materials and bracelets reveals the enhanced vibration isolation effect within a specific thickness *** vibration results of the bracelet’s outer packaging align closely with finite element simulation results,validating the effectiveness of designing and optimizing the outer *** finite element simulation,deeper understanding and prediction of the bracelet’s vibration response under various conditions is achieved,facilitating optimized packaging design for better protection and vibration damping.

关键词： Flexible polyurethane foam Packaging of fragile goods Nonlinear dynamics Vibration frequency Finite element simulation

Selective CO_(2)Electroreduction to Multi-Carbon Products on Organic-Functionalized CuO Nanoparticles by Local Micro-Environment Modulation

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Nano-Micro Letters 2024年第12期16卷 120-132页

作者： Shan Ren xi Cao Qikui Fan Zhimao yang Fei wang xin wang Licheng Bai Jian yang Materials Interfaces Center Shenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhen 518055GuangdongPeople’s Republic of China Key Laboratory of Functional Molecular Solids Ministry of EducationCollege of Chemistry and Materials ScienceAnhui Normal UniversityWuhu 241002AnhuiPeople’s Republic of China School of Physics Xi’an Jiaotong UniversityXi’an 710049ShaanxiPeople’s Republic of China College of Materials Science and Engineering Shenzhen UniversityShenzhen 518071GuangdongPeople’s Republic of China

Surface functionalization of Cu-based catalysts has demonstrated promising potential for enhancing the electrochemical CO_(2)reduction reaction(CO_(2)RR)toward multi-carbon(C2+)products,primarily by suppressing the parasitic hydrogen evolution reaction and facilitating a localized CO_(2)/CO concentration at the *** upon this approach,we developed surface-functionalized catalysts with exceptional activity and selectivity for electrocatalytic CO_(2)RR to C_(2+)in a neutral *** CuO nanoparticles coated with hexaethynylbenzene organic molecules(HEB-CuO NPs),a remarkable C_(2+)Faradaic efficiency of nearly 90%was achieved at an unprecedented current density of 300 mA cm^(-2),and a high FE(>80%)was maintained at a wide range of current densities(100-600 mA cm^(-2))in neutral environments using a flow ***,in a membrane electrode assembly(MEA)electrolyzer,86.14%FEC2+was achieved at a partial current density of 387.6 mA cm^(-2)while maintaining continuous operation for over 50 h at a current density of 200 mA cm^(-2).In-situ spectroscopy studies and molecular dynamics simulations reveal that reducing the coverage of coordinated K⋅H2O water increased the probability of intermediate reactants(CO)interacting with the surface,thereby promoting efficient C-C coupling and enhancing the yield of C_(2+)*** advancement offers significant potential for optimizing local micro-environments for sustainable and highly efficient C_(2+)production.

关键词： CO_(2)electroreduction to C_(2+) Neutral electrolyte Organic-functionalized CuO nanoparticles Local micro-environment

Multi-modular metabolic engineering of heme synthesis in Corynebacterium glutamicum

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Synthetic and Systems Biotechnology 2024年第2期9卷 285-293页

作者： Qiuyu yang xi Sun Hong wang Tao Chen Zhiwen wang Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering(Ministry of Education) Tianjin UniversityTianjin300072China SynBio Research Platform Collaborative Innovation Center of Chemical Science and Engineering(Tianjin)School of Chemical Engineering and TechnologyTianjin UniversityTianjin300072China School of Life Science Ningxia UniversityYinchuan750021China

Heme,an iron-containing porphyrin derivative,holds great promise in fields like medicine,food production and ***,we developed an engineered Corynebacterium glutamicum strain for efficient heme production by combining modular engineering and RBS *** whole heme biosynthetic pathway was methodically divided into 5-ALA synthetic module,uroporphyrinogen III(UPG III)synthetic module and heme synthetic module for further construction and *** heme synthetic modules were compared and the siroheme-dependent(SHD)pathway was identified to be optimal in *** for the first *** further improve heme production,the expression of genes in UPG III synthetic module and heme synthetic module was coordinated optimized through RBS engineering,***,heme oxygenase was knocked out to reduce heme *** engineered strain HS12 showed a maximum iron-containing porphyrin derivatives titer of 1592 mg/L with the extracellular secretion rate of 45.5%in fed-batch *** study constructed a *** chassis strain for efficient heme accumulation,which was beneficial for the advancement of efficient heme and other porphyrins production.

关键词： Corynebacterium glutamicum Heme Biosynthetic pathways Metabolic engineering

Solar energetic particles intensity variations associated with a tilted-dipole 3D corotating interaction region

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Earth and Planetary Physics 2024年第5期8卷 797-810页

作者： YuJi Zhu Fang Shen xi Luo yang wang BoFeng Tang State Key Laboratory of Space Weather National Space Science Center Chinese Academy of Sciences Shandong Institute of Advanced Technology (SDIAT) College of Earth and Planetary Sciences University of Chinese Academy of Sciences School of Science Harbin Institute of Technology

The effect of a tilted-dipole three-dimensional corotating interaction region(CIR) on the transport and acceleration of solar energetic particles(SEPs) is *** this work,we discussed how the particle intensity longitudinal and radial dependence might be influenced by the background ***,we investigate how the spectral index distribution is modulated by the CIR structure We use the focused transport equation(FTE) to describe the propagation and acceleration of SEPs in a tilt-dipole 3D CIR,generated by the high-resolution 3D magnetohydrodynamic(MHD) *** forward stochastic differential method is used to solve the *** protons with theE～(-4.4)spectrum from 0.5 to 15 MeV are injected uniformly at the heliographic equator of 0.15 *** quantities are extracted along each interplanetary magnetic field(IMF) line to show the *** the tilted-dipole CIR background,if injected from the solar equator at the inner boundary,particles in the slow flow are transported to higher latitudes due to the extension of the IMF lines to higher *** longitudinal patterns of the particles are dominated by the density of IMF *** focusing effect modulates the longitudinal variation of the particle intensity and gives rise to new longitudinal intensity *** adiabatic effect largely increases the intensity fluctuation along the *** structure of the solar wind can also lead to the difference of the index α in the empirical functionI＿(max)=kR～(-α),describing the radial variation of peak intensity according to our *** the influence of the CIR structure,the index α varies from 1.9 to 3.4 at 0.3-1.0 *** variation of the solar wind speed should be considered when estimating the radial dependence of the SEP peak *** spectra indices rise near the CIR boundaries and drop near the stream interface(SI).The adiabatic effect makes the spatial variability of the spectral index *** spectral index could be sim

关键词： solar energetic particle (SEP) corotating interaction regions (CIR) magnetohydrodynamic (MHD)

Reorganization of 3D genome architecture provides insights into pathogenesis of early fatty liver disease in laying hens

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Journal of Animal Science and Biotechnology 2024年第3期15卷 1086-1100页

作者： Yanli Liu Zhuqing Zheng Chaohui wang Yumeng wang xi Sun Zhouzheng Ren xin yang xiaojun yang College of Animal Science and Technology Northwest A&F UniversityYangling 712100China Institute of Agricultural Biotechnology Jingchu University of TechnologyJingmen 448000China

Background Fatty liver disease causes huge economic losses in the poultry industry due to its high occurrence and lethality ***-dimensional(3D)chromatin architecture takes part in disease processing by regulating tran-scriptional *** study is carried out to investigate the alterations of hepatic 3D genome and H3K27ac profiling in early fatty liver(FLS)and reveal their effect on hepatic transcriptional reprogramming in laying *** Results show that FLS model is constructed with obvious phenotypes including hepatic visible lipid deposi-tion as well as higher total triglyceride and cholesterol in serum.A/B compartment switching,topologically associat-ing domain(TAD)and chromatin loop changes are identified by high-throughput/resolution chromosome conforma-tion capture(HiC)*** genes of these alternations in hepatic 3D genome organization significantly enrich pathways related to lipid metabolism and hepatic damage.H3K27ac differential peaks and differential expres-sion genes(DEGs)identified through RNA-seq analysis are also enriched in these ***,certain DEGs are found to correspond with changes in 3D chromatin structure and H3K27ac binding in their *** motif analysis reveals that candidate transcription factors are implicated in regulating transcriptional ***,disturbed folate metabolism is observed,as evidenced by lower folate levels and altered enzyme *** Our findings establish a link between transcriptional reprogramming changes and 3D chromatin struc-ture variations during early FLS formation,which provides candidate transcription factors and folate as targets for FLS prevention or treatment.

关键词： 3D chromatin architecture Fatty liver disease Folate H3K27ac profiling Transcription reprogramming

Dynamic recrystallization behavior and strengthening mechanism of a novel Mo-Ti_(3)AlC_(2) alloy at ultrahigh temperature

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Rare Metals 2024年第8期43卷 3946-3960页

作者： Lu yang xin-Yuan Zheng yang Zhao xi-Ran wang Fang-Nao xiao Shi-Zhong Wei School of Materials Science and Engineering Henan University of Science and TechnologyLuoyang 471023China National Joint Engineering Research Center for Abrasion Control and Molding of Metal Materials Henan University of Science and TechnologyLuoyang 471003China Department of Applied Mechanics Univ.Bourgogne FrancheComteFEMTO-ST InstituteCNRS/UF/ENSMM/UTBM25000BesangonFrance

Increasing the recrystallization temperature to achieve better high-temperature performance is critical in the development of molybdenum alloys for ultrahightemperature applications,such as the newest generation of multitype high-temperature nuclear *** this study,an innovative strategy was proposed to improve the performance of molybdenum alloys at high temperature by using the two-dimensional MAX(where M is an early transition metal,A is an A-group element and X is C or N)ceramic material Ti_(3)AlC_(2).The relationships between flow stress,strain rate and temperature were *** microstructure,distribution of misorientation and evolution of dislocations in the Mo-Ti_(3)AlC_(2) alloy were *** microscopic mechanism of the Ti_(3)AlC_(2) phase in the molybdenum alloy at high temperatures was *** experimental results showed that the peak flow stress of Mo-Ti_(3)AlC_(2) at 1600℃ reached 155 MPa,which was161.8% greater than that of pure *** activation energy of thermal deformation of Mo-Ti_(3)AlC_(2) was as large as537 kJ·mol~(-1),which was 17.6% more than that of pure *** recrystallization temperature reached 1600℃ or even *** topological reaction of the Ti_(3)AlC_(2) phase consumed a large amount of energy at high temperatures,resulting in increases in the deformation activation *** structures of AlTi_3 and Ti-O Magneli-phase oxides(Ti_nO_(2n-1)) were formed in-situ,which relied on kink bands and interlayer slip,resulting in many dislocations during ***,the special two-dimensional of the structure Ti_(3)AlC_(2) ceramic inhibited the recrystallization behavior of the Mo *** results of this study can provide theoretical guidance for the development of a new generation of molybdenum alloys for use in ultrahigh-temperature environments.

关键词： Mo alloy Two-dimensional reinforcement Dynamic recrystallization behavior Hot deformation Mechanical properties