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Establishment of the“4 stages-6 sequences”repair method and quantification analysis on post-earthquake functional recovery of railway station
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作者 Song Jiayu Gao Haiwang +1 位作者 Pan Yi Jiang Junpeng 《Earthquake Engineering and Engineering Vibration》 2025年第3期827-842,共16页
Quantifying the post-earthquake functional recovery of railway stations presents significant challenges.This paper first establishes a post-earthquake function calculation method for railway stations,encompassing the ... Quantifying the post-earthquake functional recovery of railway stations presents significant challenges.This paper first establishes a post-earthquake function calculation method for railway stations,encompassing the establishment of relationships between the station’s function and the damage state,function loss,and failure probability of components and professional equipment in each layer.Also,the“4 stages-6 sequences”post-earthquake repair method is present,taking into account the functional and structural characteristics of railway stations.Additionally,a novel piecewise function for the post-earthquake functional dynamic recovery of railway stations is developed.A case study is conducted on a typical railway station to demonstrate the analysis procedure.Results indicate that under fortification,rare,and extremely rare earthquake scenarios,the interlayer drift ratio(IDR)of the railway station were 1/276,1/143,and 1/52,respectively,and corresponding peak floor acceleration(PFA)were 6.31 m/s^(2),7.82 m/s^(2),and 8.57 m/s^(2),respectively.The post-earthquake function of the railway station was 93.21%,82.33%,and 64.16%of its initial function.The repair times were 6.66 days,18.65 days,and 37.42 days.The displacement-sensitive,non-structural components were identified as the most vulnerable to damage.And the first repair stage(R_(1))which was mainly used to repair structural components and non-structural transport components,accounted for the highest proportion of total repair time. 展开更多
关键词 railway stations seismic response post-earthquake function functional recovery model repair method
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Parameter identification of magnetic levitation system based on modulation function method
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作者 Tingchen Du Xueling Fan Sheng Feng 《Control Theory and Technology》 2025年第4期602-617,共16页
A novel parameter identification method for magnetic levitation bearing rotor systems is proposed,based on the modulation function method.The fundamental principle of the modulation function method for parameter ident... A novel parameter identification method for magnetic levitation bearing rotor systems is proposed,based on the modulation function method.The fundamental principle of the modulation function method for parameter identification is derived on the basis of the characteristics of the modulation function.The transformation of the differential equation model of a continuous system into a general algebraic equation model is effectively achieved,thereby avoiding the influence of errors introduced by the initial value and differential derivation of the system.Modulation function method parameter identification models have been established for single-degree-of-freedom and multi-degree-of-freedom magnetic levitation bearing rotor systems.The influence of different parameters of Hartley modulation function on the accuracy of system parameter identification has been investigated,thus providing a basis for the design of Hartley modulation function parameters.Simulation and experimental results demonstrate that the modulation function method can effectively identify system parameters despite the presence of system noise. 展开更多
关键词 Modulation function method Hartley modulation function Magnetic levitation system Parameter identification
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Applying the Radial Basis Function Method to Estimate the Distribution of Total Suspended Matter Concentration in Hangzhou Bay
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作者 CHEN Wanqian GAO Jinpeng +5 位作者 XU Minjie LIU Zezheng LI Bingtian LV Jing LI Shujiang SUN Junchuan 《Journal of Ocean University of China》 2025年第3期557-568,共12页
Ocean remote sensing satellites provide observations with high spatiotemporal resolution.However,the influence of clouds,fog,and haze frequently leads to significant data gaps.Accurate and effective estimation of thes... Ocean remote sensing satellites provide observations with high spatiotemporal resolution.However,the influence of clouds,fog,and haze frequently leads to significant data gaps.Accurate and effective estimation of these missing data is highly valuable for engineering and scientific research.In this study,the radial basis function(RBF)method is used to estimate the spatial distribution of total suspended matter(TSM)concentration in Hangzhou Bay using remote sensing data with severe data gaps.The estimation precision is validated by comparing the results with those of other commonly used interpolation methods,such as the Kriging method and the basic spline(B-spline)method.In addition,the applicability of the RBF method is explored.Results show that the estimation of the RBF method is significantly close to the observation in Hangzhou Bay.The average of the mean absolute error,mean relative error,and root mean square error in all the experiments is evidently smaller than those of the Kriging and B-spline interpolations,indicating that the proposed method is more appropriate for estimating the spatial distribution of the TSM in Hangzhou Bay.Finally,the TSM distribution in the blank observational area is predicted.This study can provide some reference values for handling watercolor remote sensing data. 展开更多
关键词 ocean remote sensing satellite total suspended matter concentration INTERPOLATION radial basis function Kriging method basic spline method
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A step-by-step Chebyshev space-time spectral method for force vibration of functionally graded structures
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作者 Haizhou Liu Yixin Huang Yang Zhao 《Acta Mechanica Sinica》 2025年第4期142-155,共14页
This paper proposes a new step-by-step Chebyshev space-time spectral method to analyze the force vibration of functionally graded material structures.Although traditional space-time spectral methods can reduce the acc... This paper proposes a new step-by-step Chebyshev space-time spectral method to analyze the force vibration of functionally graded material structures.Although traditional space-time spectral methods can reduce the accuracy mismatch between tem-poral low-order finite difference and spatial high-order discre tization,the ir time collocation points must increase dramatically to solve highly oscillatory solutions of structural vibration,which results in a surge in computing time and a decrease in accuracy.To address this problem,we introduced the step-by-step idea in the space-time spectral method.The Chebyshev polynomials and Lagrange's equation were applied to derive discrete spatial goverming equations,and a matrix projection method was used to map the calculation results of prev ious steps as the initial conditions of the subsequent steps.A series of numerical experiments were carried out.The results of the proposed method were compared with those obtained by traditional space-time spectral methods,which showed that higher accuracy could be achieved in a shorter computation time than the latter in highly oscillatory cases. 展开更多
关键词 functionally graded materials Space-time spectral method Step-by-step approach Forced vibration
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A WKB method based on parabolic cylinder function for very-low-frequency sound propagation in deep ocean
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作者 Jian-Kang Zhan Sheng-Chun Piao +3 位作者 Li-Jia Gong Yang Dong Yong-Chao Guo Guang-Xue Zheng 《Chinese Physics B》 2025年第3期433-446,共14页
A Wentzel-Kramers-Brillouin(WKB)method is introduced for obtaining a uniform asymptotic solution for underwater sound propagation at very low frequencies in deep ocean.The method utilizes a mode sum and employs the re... A Wentzel-Kramers-Brillouin(WKB)method is introduced for obtaining a uniform asymptotic solution for underwater sound propagation at very low frequencies in deep ocean.The method utilizes a mode sum and employs the reference functions method to describe the solution to the depth-separated wave equation approximately using parabolic cylinder functions.The conditions for the validity of this approximation are also discussed.Furthermore,a formula that incorporates waveguide effects for the modal group velocity is derived,revealing that boundary effects at very low frequencies can have a significant impact on the propagation characteristics of even low-order normal modes.The present method not only offers improved accuracy compared to the classical WKB approximation and the uniform asymptotic approximation based on Airy functions,but also provides a wider range of depth applicability.Additionally,this method exhibits strong agreement with numerical methods and offers valuable physical insights.Finally,the method is applied to the study of very-low-frequency sound propagation in the South China Sea,leading to sound transmission loss predictions that closely align with experimental observations. 展开更多
关键词 WKB method normal modes very-low-frequency sound propagation parabolic cylinder function
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Optimizing basis wave functions in the generator coordinate method for microscopic cluster models (Ⅰ)
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作者 Yi‑Fan Liu Bo Zhou Yu‑Gang Ma 《Nuclear Science and Techniques》 2025年第10期183-191,共9页
We employed random distributions and gradient descent methods for the Generator Coordinate Method(GCM)to identify effective basis wave functions,taking halo nuclei ^(6)He and ^(6)Li as examples.By comparing the ground... We employed random distributions and gradient descent methods for the Generator Coordinate Method(GCM)to identify effective basis wave functions,taking halo nuclei ^(6)He and ^(6)Li as examples.By comparing the ground state(0^(+))energy of ^(6)He and the excited state(0^(+))energy of 6 Li calculated with various random distributions and manually selected generation coordinates,we found that the heavy tail characteristic of the logistic distribution better describes the features of the halo nuclei.Subsequently,the Adam algorithm from machine learning was applied to optimize the basis wave functions,indicating that a limited number of basis wave functions can approximate the converged values.These results offer some empirical insights for selecting basis wave functions and contribute to the broader application of machine learning methods in predicting effective basis wave functions. 展开更多
关键词 Generator Coordinate method Effective basis wave functions Nuclear cluster model Machine learning Halo nuclei
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Middle Ear Transfer Function for Sound Conduction Study of Middle Ear Implants:A New Method
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作者 Yueqi Li Xiao Qin +1 位作者 Guodong Feng Zhiqiang Gao 《Journal of Otology》 2025年第4期219-224,共6页
Human temporal bone specimens are used in experiments to measure the sound transfer function of the middle ear.This standard method for the development of middle ear implants requires temporal bones that possess appro... Human temporal bone specimens are used in experiments to measure the sound transfer function of the middle ear.This standard method for the development of middle ear implants requires temporal bones that possess appropriate mechanical properties and structural stability and are free from pathological conditions.A laser Doppler vibrometer is commonly employed to measure the vibration of the stapes footplate.These experiments are typically conducted in the middle ear by leaving the inner ear intact,exposing the stapes footplate through the tympanic cavity,and directing the laser beam onto the footplate.However,previous studies have shown that the influence of inner ear impedance on the middle ear transfer function cannot be ignored,and any surgical manipulation may cause a change in inner ear pressure,resulting in instability in the middle ear transfer function.Therefore,this study aims to eliminate the influence of the inner ear and to establish a new experimental method in human temporal bone specimens that is more suitable for the study of sound conduction in middle ear implants.As a result,a range for middle ear transfer function was developed,which serves as a reference for assessing the conformity of temporal bone specimens to experimental standards,and the stability of this range was demonstrated under experimental conditions. 展开更多
关键词 MIDDLE EAR transfer function Laser DOPPLER VIBROMETRY Temporal BONE STAPES footplate
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Applying the Liouville–Lanczos method of time-dependent density-functional theory to warm dense matter
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作者 Zhandos A.Moldabekov Sebastian Schwalbe +3 位作者 Thomas Gawne Thomas R.Preston Jan Vorberger Tobias Dornheim 《Matter and Radiation at Extremes》 2025年第4期44-57,共14页
Ab initio modeling of dynamic structure factors(DSF)and related density response properties in the warm dense matter(WDM)regime is a challenging computational task.The DSF,convolved with a probing X-ray beam and instr... Ab initio modeling of dynamic structure factors(DSF)and related density response properties in the warm dense matter(WDM)regime is a challenging computational task.The DSF,convolved with a probing X-ray beam and instrument function,is measured in X-ray Thom-son scattering(XRTS)experiments,which allow the study of electronic structure properties at the microscopic level.Among the various ab initio methods,linear-response time-dependent density-functional theory(LR-TDDFT)is a key framework for simulating the DSF.The standard approach in LR-TDDFT for computing the DSF relies on the orbital representation.A significant drawback of this method is the unfavorable scaling of the number of required empty bands as the wavenumber increases,making LR-TDDFT impractical for modeling XRTS measurements over large energy scales,such as in backward scattering geometry.In this work,we consider and test an alternative approach to LR-TDDFT that employs the Liouville–Lanczos(LL)method for simulating the DSF of WDM.This approach does not require empty states and allows the DSF at large momentum transfer values and over a broad frequency range to be accessed.We compare the results obtained from the LL method with those from the solution of Dyson’s equation using the standard LR-TDDFT within the projector augmented-wave formalism for isochorically heated aluminum and warm dense hydrogen.Additionally,we utilize exact path integral Monte Carlo results for the imaginary-time density-density correlation function(ITCF)of warm dense hydrogen to rigorously benchmark the LL approach.We discuss the application of the LL method for calculating DSFs and ITCFs at different wavenumbers,the effects of pseudopotentials,and the role of Lorentzian smearing.The successful validation of the LL method under WDM conditions makes it a valuable addition to the ab initio simulation landscape,supporting experimental efforts and advancing WDM theory. 展开更多
关键词 ab initio dynamic structure factors dsf Liouville Lanczos method simulating ds ab initio methodslinear response warm dense matter time dependent density functional theory density response properties
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The Analysis of Gauss Radial Basis Functions and Its Application in Locating Olivine on the Moon
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作者 SONG Shicang SONG Xiaoyuan SONG Shuhan 《应用数学》 北大核心 2026年第1期173-181,共9页
Gauss radial basis functions(GRBF)are frequently employed in data fitting and machine learning.Their linear independence property can theoretically guarantee the avoidance of data redundancy.In this paper,one of the m... Gauss radial basis functions(GRBF)are frequently employed in data fitting and machine learning.Their linear independence property can theoretically guarantee the avoidance of data redundancy.In this paper,one of the main contributions is proving this property using linear algebra instead of profound knowledge.This makes it easy to read and understand this fundamental fact.The proof of linear independence of a set of Gauss functions relies on the constructing method for one-dimensional space and on the deducing method for higher dimensions.Additionally,under the condition of preserving the same moments between the original function and interpolating function,both the interpolating existence and uniqueness are proven for GRBF in one-dimensional space.The final work demonstrates the application of the GRBF method to locate lunar olivine.By combining preprocessed data using GRBF with the removing envelope curve method,a program is created to find the position of lunar olivine based on spectrum data,and the numerical experiment shows that it is an effective scheme. 展开更多
关键词 Gauss function Radial basis function Machine learning Lunar olivine locating Data fitting
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Evaluating the Impact of Different Electrocardiogram Methods on Detecting Pacemaker Dysfunction and Cardiac Function Changes in Pacemaker Patients
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作者 Yan Li Chun Zhou +1 位作者 Ying Li Binlin Chen 《Journal of Clinical and Nursing Research》 2025年第8期7-13,共7页
Objective:To investigate the effect of 12-lead electrocardiogram and 24-hour dynamic electrocardiogram in detecting pacemaker dysfunction and changes in cardiac function indexes in patients with pacemaker implantation... Objective:To investigate the effect of 12-lead electrocardiogram and 24-hour dynamic electrocardiogram in detecting pacemaker dysfunction and changes in cardiac function indexes in patients with pacemaker implantation.Methods:A total of 136 patients with pacemaker implantation in the First Clinical Medical College of Three Gorges University,Institute of Cardiovascular Disease of Three Gorges University and Yicang Central People’s Hospital from January 2023 to December 2024 were selected as the research objects.All patients received 12-lead electrocardiogram and 24-hour holter 3–14 days after implantation.Results:The overall detection rate of various types of pacemaker dysfunction by Holter was significantly higher than that by conventional ECG(27.21%vs.5.15%,χ^(2)=24.402,P<0.001).The overall arrhythmia detection rate of Holter was significantly higher than that of conventional electrocardiogram(57.35%vs.10.29%,χ^(2)=67.277,P<0.001).The time domain indexes of heart rate variability obtained by 24-hour continuous monitoring of Holter were significantly improved compared with those of conventional electrocardiogram(P<0.05).Conclusions:Compared with 12-lead electrocardiogram,24-hour holter monitoring can more accurately detect pacemaker dysfunction and arrhythmia in patients with pacemaker implantation,and provide more comprehensive data of heart rate variability,which is helpful for clinicians to better evaluate the cardiac function of patients and adjust treatment plans. 展开更多
关键词 Pacemaker implantation ELECTROCARDIOGRAM Abnormal pacemaker function Cardiac arrhythmia Heart rate variability
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Extraction of Modal Depth Functions and Wavenumbers Using Full Rank Decomposition Method with a Vertical Line Array
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作者 ZHANG Shuang ZHANG Yinquan +3 位作者 QIN Jinxing LI Zhenglin GUO Yonggang WU Shuanglin 《Journal of Ocean University of China》 2025年第3期672-684,共13页
Normal mode extraction has attracted extensive attention over the past few decades due to its practical value in enhancing the performance of underwater acoustic signal processing.Singular value decomposition(SVD)is a... Normal mode extraction has attracted extensive attention over the past few decades due to its practical value in enhancing the performance of underwater acoustic signal processing.Singular value decomposition(SVD)is an effective method to extract modal depth functions using vertical line arrays(VLA),particularly in scenarios when no prior environment information is available.However,the SVD method requires rigorous orthogonality conditions,and its performance severely degenerates in the presence of mode degeneracy.Consequently,the SVD approach is often not feasible in practical scenarios.This paper proposes a full rank decomposition(FRD)method to address these issues.Compared to the SVD method,the FRD method has three distinct advantages:1)the conditions that the FRD method requires are much easier to be fulfilled in practical scenarios;2)both modal depth functions and wavenumbers can be simultaneously extracted via the FRD method;3)the FRD method is not affected by the phenomenon of mode degeneracy.Numerical simulations are conducted in two types of waveguides to verify the FRD method.The impacts of environment configurations and noise levels on the precision of the extracted modal depth functions and wavenumbers are also investigated through simulation. 展开更多
关键词 normal mode extraction modal depth function modal wavenumber full rank decomposition
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A Novel Functional Method of Protector Screening for Zebrafish Lateral Line Hair Cells via the Acoustic Escape Response
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作者 Ling Zheng Qiaosen Shen +8 位作者 Tong Zhao Qingsong Liu Zihao Huang Feng Zhao Mengqian Zhang Yongdong Song Daogong Zhang Dong Liu Fangyi Chen 《Neuroscience Bulletin》 2025年第9期1537-1552,共16页
Zebrafish larvae are useful for identifying chemicals against lateral line(LL)hair cell(HC)damage and this type of chemical screen mainly focuses on searching for protectors against cell death.To expand the candidate ... Zebrafish larvae are useful for identifying chemicals against lateral line(LL)hair cell(HC)damage and this type of chemical screen mainly focuses on searching for protectors against cell death.To expand the candidate pool of HC protectors,a self-built acoustic escape response(AER)-detecting system was developed to apply both low-frequency near-field sound transmission and AER image acquisition/processing modules.The device quickly confirmed the changed LL HC functions caused by most known ototoxins,protectors,and neural transmission modifiers,or knockdown of LL HC-expressing genes.With ten devices wired in tandem,five‘hit’chemicals were identified from 124 cyclin-dependent kinase inhibitors to partially restore cisplatin-damaged AER in less than a day.AS2863619,ribociclib,and SU9516 among the hits,protected the HCs in the mouse cochlea.Therefore,using free-swimming larval zebrafish,the self-made AER-detecting device can efficiently identify compounds that are protective against HC damage,including cell death and loss-of-function. 展开更多
关键词 Acoustic escape response Zebrafish Lateral line Hair cell Low-frequency sound functional screening
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Microglia overexpressing brain-derived neurotrophic factor promote vascular repair and functional recovery in mice after spinal cord injury 被引量:2
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作者 Fanzhuo Zeng Yuxin Li +6 位作者 Xiaoyu Li Xinyang Gu Yue Cao Shuai Cheng He Tian Rongcheng Mei Xifan Mei 《Neural Regeneration Research》 2026年第1期365-376,共12页
Spinal cord injury represents a severe form of central nervous system trauma for which effective treatments remain limited.Microglia is the resident immune cells of the central nervous system,play a critical role in s... Spinal cord injury represents a severe form of central nervous system trauma for which effective treatments remain limited.Microglia is the resident immune cells of the central nervous system,play a critical role in spinal cord injury.Previous studies have shown that microglia can promote neuronal survival by phagocytosing dead cells and debris and by releasing neuroprotective and anti-inflammatory factors.However,excessive activation of microglia can lead to persistent inflammation and contribute to the formation of glial scars,which hinder axonal regeneration.Despite this,the precise role and mechanisms of microglia during the acute phase of spinal cord injury remain controversial and poorly understood.To elucidate the role of microglia in spinal cord injury,we employed the colony-stimulating factor 1 receptor inhibitor PLX5622 to deplete microglia.We observed that sustained depletion of microglia resulted in an expansion of the lesion area,downregulation of brain-derived neurotrophic factor,and impaired functional recovery after spinal cord injury.Next,we generated a transgenic mouse line with conditional overexpression of brain-derived neurotrophic factor specifically in microglia.We found that brain-derived neurotrophic factor overexpression in microglia increased angiogenesis and blood flow following spinal cord injury and facilitated the recovery of hindlimb motor function.Additionally,brain-derived neurotrophic factor overexpression in microglia reduced inflammation and neuronal apoptosis during the acute phase of spinal cord injury.Furthermore,through using specific transgenic mouse lines,TMEM119,and the colony-stimulating factor 1 receptor inhibitor PLX73086,we demonstrated that the neuroprotective effects were predominantly due to brain-derived neurotrophic factor overexpression in microglia rather than macrophages.In conclusion,our findings suggest the critical role of microglia in the formation of protective glial scars.Depleting microglia is detrimental to recovery of spinal cord injury,whereas targeting brain-derived neurotrophic factor overexpression in microglia represents a promising and novel therapeutic strategy to enhance motor function recovery in patients with spinal cord injury. 展开更多
关键词 ANGIOGENESIS apoptosis brain-derived neurotrophic factor colony stimulating factor 1 receptor inflammation MICROGLIA motor function spinal cord injury vascular endothelial growth factor
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A diagnosis method based on graph neural networks embedded with multirelationships of intrinsic mode functions for multiple mechanical faults
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作者 Bin Wang Manyi Wang +3 位作者 Yadong Xu Liangkuan Wang Shiyu Chen Xuanshi Chen 《Defence Technology(防务技术)》 2025年第8期364-373,共10页
Fault diagnosis occupies a pivotal position within the domain of machine and equipment management.Existing methods,however,often exhibit limitations in their scope of application,typically focusing on specific types o... Fault diagnosis occupies a pivotal position within the domain of machine and equipment management.Existing methods,however,often exhibit limitations in their scope of application,typically focusing on specific types of signals or faults in individual mechanical components while being constrained by data types and inherent characteristics.To address the limitations of existing methods,we propose a fault diagnosis method based on graph neural networks(GNNs)embedded with multirelationships of intrinsic mode functions(MIMF).The approach introduces a novel graph topological structure constructed from the features of intrinsic mode functions(IMFs)of monitored signals and their multirelationships.Additionally,a graph-level based fault diagnosis network model is designed to enhance feature learning capabilities for graph samples and enable flexible application across diverse signal sources and devices.Experimental validation with datasets including independent vibration signals for gear fault detection,mixed vibration signals for concurrent gear and bearing faults,and pressure signals for hydraulic cylinder leakage characterization demonstrates the model's adaptability and superior diagnostic accuracy across various types of signals and mechanical systems. 展开更多
关键词 Fault diagnosis Graph neural networks Graph topological structure Intrinsic mode functions Feature learning
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Comparative study of Fe(Ⅱ)/Fe(Ⅲ) ions reaction in electrochemical polarization process of 304 stainless steel in H_(2)SO_(4) and bipyridine solutions employing experimental and density functional theory methods
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作者 Jiantao QI Yongqiang ZHU +5 位作者 Hao REN Dazhao YU Guixue BIAN Peijuan LI Tengjiao LI Sihang CHEN 《Chinese Journal of Aeronautics》 2025年第6期591-604,共14页
Localized corrosion of 304 stainless steel being the significant parts of Starship rocket seriously threatens the long-term service of such aerospace equipment.Scanning electron microscopy,in situ instruments combinin... Localized corrosion of 304 stainless steel being the significant parts of Starship rocket seriously threatens the long-term service of such aerospace equipment.Scanning electron microscopy,in situ instruments combining electrochemical workstation and Raman spectroscopy,and Density Dunctional Theory(DFT)calculations were employed.The surface morphologies,alloying elements,molecular fingerprint Raman evidence and theoretical mechanism for the localized corrosion of 304 stainless steel during the electrochemical polarization in the mixture solutions containing 0.5 mol/L H_(2)SO_(4) and 2,2'-bipyridine(bipy)with concentrations of 0.001,0.010,0.100 mol/L were discussed.In comparison,the presence of bipy up to 0.100 mol/L in such mixture solutions displayed the neglectable effect on the Fe(Ⅱ)/Fe(Ⅲ)reaction in the polarization process.Raman vibrational frequency around 1492 cm^(-1)was the evidence of pink color appearance due to the formation of[Fe^(Ⅱ)(bipy)_(3)]^(2+).Raman and DFT indicated the yellow color emergence due to the presence ofμ-O-[Fe^(Ⅲ)(bipy)_(2)(H_(2)O)]_(2)^(4+)due to the oxidation reaction of[Fe^(Ⅱ)(bipy)_(3)]^(2+)with H_(2)O_(2) oxidant,and the dimerization of[Fe^(Ⅲ)(bipy)_(3)]^(3+),Furthermore,a quantitative model between[Fe^(Ⅱ)(bipy)_(3)]^(2+)concentration and Raman intensity at 1492 cm^(-1) has been built up.Two linear functions were revealed when[Fe^(Ⅱ)(bipy)_(3)]^(2+)concentrations were at 0-0.002 mol/L and 0.002-0.004 mol/L and a concentration error of less than 5%was evidenced in comparison with that investigated by the inductively coupled plasma.The proposed passivation mechanism and quantitative concentration model of 304 stainless steel have certain significance for its corrosion protection andcorrosionevaluation. 展开更多
关键词 Corrosion Density functional theory Fe(Ⅱ)/Fe(Ⅲ) RAMAN Stainless steel
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Mechanistic insights into“Three Methods and Three Acupoints”Tuina therapy for improving spinal microcirculation and motor function in sciatic nerve injury model rats
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作者 Hanyu Zhang Yingqi Zhang +6 位作者 Hourong Wang Jiayue Liu Jiawei Sun Jinping Chen Zhifeng Liu Tianyuan Yu Jian Shu 《Journal of Traditional Chinese Medical Sciences》 2025年第1期125-134,共10页
Objective:To investigate the effects of“Three Methods and Three Acupoints”(TMTP)Tuina therapy on spinal microcirculation in sciatic nerve injury(SNI).Methods:Thirty-six SpragueeDawley rats were randomly assigned to ... Objective:To investigate the effects of“Three Methods and Three Acupoints”(TMTP)Tuina therapy on spinal microcirculation in sciatic nerve injury(SNI).Methods:Thirty-six SpragueeDawley rats were randomly assigned to four groups:normal,sham operation,model,and TMTP Tuina.Successful model induction was confirmed by observable hind limb lameness.After 20 sessions,hind limb grip strength and motor nerve conduction velocity(MNCV)were measured at baseline and following the 10th and 20th intervention.CD31 and a-SMA in the ventral horn of SNI model rats were detected using immunofluorescence.Motor neurons in the ventral horn were detected by Nissl staining.PTEN levels in the ventral horn were measured by ELISA,and PI3K,Akt,BDNF,VEGF,and HIF-1a expression was determined by RT-PCR.Spinal cord microcirculation was evaluated by western blotting analysis of the levels of Akt,p-Akt,BDNF,and VEGF.Results:Hind limb grip strength and MNCV significantly improved in the TMTP Tuina group compared to the model group(both P<.001).Morphology of ventral horn motor neurons in the TMTP Tuina group improved compared to the model group,with increased expressions of a-SMA(P=.002)and CD31(P=.006).Western blot analysis indicated increased expression of VEGF(P=.005),p-Akt(P<.001),and BDNF(P=.008)in the ventral horn following Tuina treatment.RT-PCR analysis revealed increased expression of PI3K,Akt,BDNF,VEGF and HIF-1a(all P<.05).In contrast,expression of PTEN decreased compared to the model group(P<.001).Conclusion:TMTP Tuina therapy may restore motor function in rats,enhance ventral horn motor neuron morphology,and promote angiogenesis and vascular smooth muscle proliferation.The mechanism may involve the activation of the PI3K/Akt signaling pathway. 展开更多
关键词 Three methods and Three Acupoints TUINA Spinal cord MICROCIRCULATION PI3K/Akt
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Microscopic calculation of photon strength functions in Nd isotopes using the dirac quasiparticle finite amplitude method
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作者 Hai-Ruo Liu Yuan Tian +7 位作者 Rui-Rui Xu Yi-Fei Niu Ying Cui Xi Tao Xiao-Dong Sun Zhi Zhang Zhi-Gang Ge Neng-Chuan Shu 《Nuclear Science and Techniques》 2025年第12期304-311,共8页
In this study,we calculated the photon absorption cross sections of even–even neodymium(Nd)isotopes using the Dirac Quasiparticle Finite Amplitude Method(relativistic QFAM),combined with the Tiny Smearing Approximati... In this study,we calculated the photon absorption cross sections of even–even neodymium(Nd)isotopes using the Dirac Quasiparticle Finite Amplitude Method(relativistic QFAM),combined with the Tiny Smearing Approximation(TSA)method.This approach enables the efficient reproduction of experimental photon absorption data for both spherical and deformed nuclei.We demonstrate that relativistic QFAM calculations with any smearing parameter γ can be scaled using the TSA method,significantly reducing the computational cost.Our method was applied to Nd isotopes,with experimental data reproduced for ^(142,144,146,148,150)Nd and predictions for ^(152)Nd.By optimizing the three key parameters,the total χ^(2) between the calculations and experimental data was reduced by nearly an order of magnitude.Furthermore,the role of nuclear deformation in the Giant Dipole Resonance(GDR)structure was analyzed,highlighting its impact on the emergence of double peaks in the photon absorption cross sections of deformed nuclei.This work provides a robust microscopic approach to improve photonuclear data for applications in nuclear physics and astrophysics. 展开更多
关键词 Relativistic mean field Relativistic quasiparticle finite amplitude method Photon-nuclear reaction Photon absorption cross section
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A New Inversion-free Iterative Method for Solving the Nonlinear Matrix Equation and Its Application in Optimal Control
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作者 GAO Xiangyu XIE Weiwei ZHANG Lina 《应用数学》 北大核心 2026年第1期143-150,共8页
In this paper,we consider the maximal positive definite solution of the nonlinear matrix equation.By using the idea of Algorithm 2.1 in ZHANG(2013),a new inversion-free method with a stepsize parameter is proposed to ... In this paper,we consider the maximal positive definite solution of the nonlinear matrix equation.By using the idea of Algorithm 2.1 in ZHANG(2013),a new inversion-free method with a stepsize parameter is proposed to obtain the maximal positive definite solution of nonlinear matrix equation X+A^(*)X|^(-α)A=Q with the case 0<α≤1.Based on this method,a new iterative algorithm is developed,and its convergence proof is given.Finally,two numerical examples are provided to show the effectiveness of the proposed method. 展开更多
关键词 Nonlinear matrix equation Maximal positive definite solution Inversion-free iterative method Optimal control
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Artificial intelligence in functional gastrointestinal disorders:From precision diagnosis to preventive healthcare
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作者 Yi-Nan Yan Jing-Qi Zeng Xia Ding 《Artificial Intelligence in Gastroenterology》 2026年第1期20-35,共16页
Functional gastrointestinal disorders(FGIDs),including irritable bowel syndrome(IBS),functional dyspepsia(FD),and gastroesophageal reflux disease(GERD),present persistent diagnostic and therapeutic challenges due to s... Functional gastrointestinal disorders(FGIDs),including irritable bowel syndrome(IBS),functional dyspepsia(FD),and gastroesophageal reflux disease(GERD),present persistent diagnostic and therapeutic challenges due to symptom heterogeneity and the absence of reliable biomarkers.Artificial intelligence(AI)enables the integration of multimodal data to enhance FGID management through precision diagnostics and preventive healthcare.This minireview summarizes recent advancements in AI applications for FGIDs,highlighting progress in diagnostic accuracy,subtype classification,personalized interventions,and preventive strategies inspired by the traditional Chinese medicine concept of“treating the undiseased”.Machine learning and deep learning algorithms have demonstrated value in improving IBS diagnosis,refining FD neuro-gastrointestinal subtyping,and screening for GERD-related complications.Moreover,AI supports dietary,psychological,and integrative medicine-based interventions to improve patient adherence and quality of life.Nonetheless,key challenges remain,including data heterogeneity,limited model interpretability,and the need for robust clinical validation.Future directions emphasize interdisciplinary collaboration,the development of multimodal and explainable AI models,and the creation of patientcentered platforms to facilitate a shift from reactive treatment to proactive prevention.This review provides a systematic framework to guide the clinical application and theoretical innovation of AI in FGIDs. 展开更多
关键词 Artificial intelligence functional gastrointestinal disorders Irritable bowel syndrome functional dyspepsia Gastroesophageal reflux disease
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Silent cardiac burden:Echocardiographic abnormalities and their predictors in kidney transplant candidates and their impact on graft function
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作者 Nihal Mohammed Sadagah Muhammad Abdul Mabood Khalil +3 位作者 Hinda Hassan Khideer Mahmood Ibtisam Ali Alghamdi Ghada Abdulrahman Buridi Salem H Al-Qurashi 《World Journal of Transplantation》 2026年第1期167-181,共15页
BACKGROUND An echocardiogram is an essential tool in the evaluation of potential kidney transplant recipients(KTRs).Despite cardiac clearance,potential KTRs still have structural and functional abnormalities.Identifyi... BACKGROUND An echocardiogram is an essential tool in the evaluation of potential kidney transplant recipients(KTRs).Despite cardiac clearance,potential KTRs still have structural and functional abnormalities.Identifying the prevalence of these abnormalities and understanding their predictors is vital for optimizing pretransplant risk stratification and improving post-transplant outcomes.AIM To determine the prevalence of left ventricular hypertrophy(LVH),left ventricular systolic dysfunction(LVSD),diastolic dysfunction(DD),pulmonary hypertension(PH),and their predictors,and to assess their impact on graft function in pre-transplant candidates.METHODS The study included all successful transplant candidates older than 14 who had a baseline echocardiogram.Binary logistic regression models were constructed to identify factors associated with LVH,LVSD,DD,and PH.RESULTS Out of 259 patients,LVH was present in 64%(166),12%(31)had LVSD,27.5%(71)had DD,and 66(25.5%)had PH.Independent predictors of LVH included male gender[odds ratio(OR):2.51;95%CI:1.17-5.41 P=0.02],PH(OR=2.07;95%CI:1.11-3.86;P=0.02),DD(OR:2.47;95%CI:1.29-4.73;P=0.006),and dyslipidemia(OR=1.94;95%CI:1.07-3.53;P=0.03).Predictors for LVSD included patients with DD(OR=3.3,95%CI:1.41-7.81;P=0.006)and a family history of coronary artery disease(OR=4.50,95%CI:1.33-15.20;P=0.015).Peritoneal dialysis was an independent predictor for DD(OR=10.03;95%CI:1.71-58.94,P=0.011).The presence of LVH(OR=3.32,95%CI:1.05-10.55,P=0.04)and mild to moderate or moderate to severe mitral regurgitation(OR=4.63,95%CI:1.45-14.78,P=0.01)were significant factors associated with PH.These abnormalities had no significant impact on estimated glomerular filtration at discharge,6 months,1 year,or 2 years post-transplant.CONCLUSION Significant echocardiographic abnormalities persist in a potential transplant candidate despite cardiac clearance,although they don’t affect future graft function.Understanding the risk factors associated with these abnormalities may help clinicians address these factors pre-and post-transplant to achieve better outcomes. 展开更多
关键词 Echocardiographic abnormalities Kidney transplant PREDICTORS Graft function
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