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Construction of Even-Variable 2-Output Almost Optimal Five-Valued Spectra Boolean Functions
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作者 SONG Chao-Fan JI Yan-Han SUN Yu-Juan 《密码学报(中英文)》 北大核心 2025年第3期714-728,共15页
Five-valued Boolean functions play an important role in the design of symmetric cryptography.While the design and properties of single-output almost optimal five-valued spectra Boolean functions have been extensively ... Five-valued Boolean functions play an important role in the design of symmetric cryptography.While the design and properties of single-output almost optimal five-valued spectra Boolean functions have been extensively studied over the past few decades,there has been limited research on the construction of almost optimal five-valued spectra vectorial Boolean functions.In this paper,we present a construction method for even-variable 2-output almost optimal five-valued spectra balanced Boolean functions,whose Walsh spectra values belong to the set{0,±2^(n/2),±2^(n/2+1)},at the same time,we discuss the existence of sufficient conditions in the construction.Additionally,this paper presents a novel construction method for balanced single-output Boolean functions with even variables featuring a special five-valued spectral structure,whose Walsh spectra values are constrained to the set{0,±2^(n/2),±3·2^(n/2)}.These functions provide new canonical examples for the study of Boolean function spectral theory. 展开更多
关键词 Boolean function Walsh transform semi-bent function five-valued function totally disjoint spectra functions
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Metallogenic environment in central southern Tanlu Fault revealed by P-wave tomography
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作者 Ya SUN Zi-jun YUAN +3 位作者 Ji-wen HUANG Jian-tai ZHANG Fu-quan LI Jian-xin LIU 《Transactions of Nonferrous Metals Society of China》 2025年第9期3108-3119,共12页
A P-wave velocity model was built in the central southern of the Tanlu Fault based on double-difference tomography.The results suggest the presence of a low-velocity anomaly extending from the surface to a depth of 25... A P-wave velocity model was built in the central southern of the Tanlu Fault based on double-difference tomography.The results suggest the presence of a low-velocity anomaly extending from the surface to a depth of 25 km around the Tanlu and Feixi Faults,representing fault-related fluids caused by partial melting.The relocated earthquakes indicate a significant concentration of seismic activity above 20 km around the Tanlu and Feixi Faults,suggesting that prominent fault systems possibly serve as conduits for the upward migration of deep minerals.The proposed geodynamic model,supported by geological and geophysical data,suggests that the migration of deep mineralized materials extends along the Tanlu Fault.The obtained results serve as a crucial foundation for elucidating the intricate process of mineralization in the central southern segment of the Tanlu Fault,thereby enhancing comprehension regarding the interaction among ore body formation,fault fluids,localized melting,and seismic activity. 展开更多
关键词 central southern Tanlu Fault double-difference tomography MINERALIZATION partial melting p-wave velocity
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WITHDRAWAL:Predicting Irreducible Water Saturation of Unconventional Reservoirs by Using NMR T2 Spectra:Methods of Morphological Division and Fractal Models
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《Acta Geologica Sinica(English Edition)》 2025年第2期625-625,共1页
WITHDRAWAL:Zhang,J.J.,Guo,Y.Q.,Qin,Z.Y.,Wei,C.T.,Hu,Q.H.,Vandeginste,V.,Miao,H.Y.,Yao,P.,and Zhang,P.F.,“Predicting Irreducible Water Saturation of Unconventional Reservoirs by Using NMR T2 Spectra:Methods of Morphol... WITHDRAWAL:Zhang,J.J.,Guo,Y.Q.,Qin,Z.Y.,Wei,C.T.,Hu,Q.H.,Vandeginste,V.,Miao,H.Y.,Yao,P.,and Zhang,P.F.,“Predicting Irreducible Water Saturation of Unconventional Reservoirs by Using NMR T2 Spectra:Methods of Morphological Division and Fractal Models”,Acta Geologica Sinica-English Edition(Accepted Article):https://doi.org/10.1111/1755-6724.15094. 展开更多
关键词 fractal models morphological division nmr t spectra methods fractal models acta irreducible water saturation nmr t spectra
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Central-Pixel Guiding Sub-Pixel and Sub-Channel Convolution Network for Hyperspectral Image Classification
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作者 Xin Guan Shan Wang Qiang Li 《Journal of Beijing Institute of Technology》 2025年第5期510-525,共16页
In hyperspectral image classification(HSIC),accurately extracting spatial and spectral information from hyperspectral images(HSI)is crucial for achieving precise classification.However,due to low spatial resolution an... In hyperspectral image classification(HSIC),accurately extracting spatial and spectral information from hyperspectral images(HSI)is crucial for achieving precise classification.However,due to low spatial resolution and complex category boundary,mixed pixels containing features from multiple classes are inevitable in HSIs.Additionally,the spectral similarity among different classes challenge for extracting distinctive spectral features essential for HSIC.To address the impact of mixed pixels and spectral similarity for HSIC,we propose a central-pixel guiding sub-pixel and sub-channel convolution network(CP-SPSC)to extract more precise spatial and spectral features.Firstly,we designed spatial attention(CP-SPA)and spectral attention(CP-SPE)informed by the central pixel to effectively reduce spectral interference of irrelevant categories in the same patch.Furthermore,we use CP-SPA to guide 2D sub-pixel convolution(SPConv2d)to capture spatial features finer than the pixel level.Meanwhile,CP-SPE is also utilized to guide 1D sub-channel con-volution(SCConv1d)in selecting more precise spectral channels.For fusing spatial and spectral information at the feature-level,the spectral feature extension transformation module(SFET)adopts mirror-padding and snake permutation to transform 1D spectral information of the center pixel into 2D spectral features.Experiments on three popular datasets demonstrate that ours out-performs several state-of-the-art methods in accuracy. 展开更多
关键词 hyperspectral image classification similar spectra mixed pixel ATTENTION
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Metaheuristic multi-objective optimization-based microseismic source location approach with anisotropic P-wave velocity field
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作者 Xin Yin Feng Gao +3 位作者 Honggan Yu Yucong Pan Quansheng Liu He Liu 《Deep Resources Engineering》 2025年第1期38-53,共16页
Rockburst is a common dynamic geological hazard,frequently occurring in underground engineering(e.g.,TBM tunnelling and deep mining).In order to achieve rockburst monitoring and warning,the microseismic moni-toring te... Rockburst is a common dynamic geological hazard,frequently occurring in underground engineering(e.g.,TBM tunnelling and deep mining).In order to achieve rockburst monitoring and warning,the microseismic moni-toring technique has been widely used in the field.However,the microseismic source location has always been a challenge,playing a vital role in the precise prevention and control of rockburst.To this end,this study proposes a novel microseismic source location model that considers the anisotropy of P-wave velocity.On the one hand,it assigns a unique P-wave velocity to each propagation path,abandoning the assumption of a homogeneous ve-locity field.On the other hand,it treats the P-wave velocity as a co-inversion parameter along with the source location,avoiding the predetermination of P-wave velocity.To solve this model,three various metaheuristic multi-objective optimization algorithms are integrated with it,including the whale optimization algorithm,the butterfly optimization algorithm,and the sparrow search algorithm.To demonstrate the advantages of the model in terms of localization accuracy,localization efficiency,and solution stability,four blasting cases are collected from a water diversion tunnel project in Xinjiang,China.Finally,the effect of the number of involved sensors on the microseismic source location is discussed. 展开更多
关键词 Underground engineering Microseismic monitoring Microseismic source location p-wave velocity anisotropy Metaheuristic multi-objective optimization
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Non-specific/specific SERS spectra concatenation for precise bacteria classifications with few samples using a residual neural network
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作者 Feihu Wu Gengwen Chen +10 位作者 Kaitao Lai Shiqing Zhang Yingchao Liu Ruijian Luo Xiaocong Wang Pinzhi Cao Yi Ye Jiarong Lian Junle Qu Zhigang Yang Xiaojun Peng 《Chinese Chemical Letters》 2025年第1期484-490,共7页
Deep learning neural network incorporating surface enhancement Raman scattering technique(SERS)is becoming as a powerful tool for the precise classifications and diagnosis of bacterial infections.However,the large amo... Deep learning neural network incorporating surface enhancement Raman scattering technique(SERS)is becoming as a powerful tool for the precise classifications and diagnosis of bacterial infections.However,the large amount of sample requirement and time-consuming sample collection severely hinder its applications.We herein propose a spectral concatenation strategy for residual neural network using nonspecific and specific SERS spectra for the training data augmentation,which is accessible to acquiring larger training dataset with same number of SERS spectra or same size of training dataset with fewer SERS spectra,compared with pure non-specific SERS spectra.With this strategy,the training loss exhibit rapid convergence,and an average accuracy up to 100%in bacteria classifications was achieved with50 SERS spectra for each kind of bacterium;even reduced to 20 SERS spectra per kind of bacterium,classification accuracy is still>95%,demonstrating marked advantage over the results without spectra concatenation.This method can markedly improve the classification accuracy under fewer samples and reduce the data collection workload,and can evidently enhance the performance when used in different machine learning models with high generalization ability.Therefore,this strategy is beneficial for rapid and accurate bacteria classifications with residual neural network. 展开更多
关键词 SERS Deep learning Resnet Bacteria classification spectra concatenation
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Extraction of fissile isotope antineutrino spectra using feedforward neural network
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作者 Jian Chen Jun Wang +1 位作者 Wei Wang Yue-Huan Wei 《Nuclear Science and Techniques》 2025年第10期13-23,共11页
The precise measurement of the antineutrino spectra produced by isotope fission in reactors is of great significance for studying neutrino oscillations,refining nuclear databases,and addressing the reactor antineutrin... The precise measurement of the antineutrino spectra produced by isotope fission in reactors is of great significance for studying neutrino oscillations,refining nuclear databases,and addressing the reactor antineutrino anomaly.In this paper,we report a method that utilizes a feedforward neural network(FNN)model to decompose the prompt energy spectrum observed in a short-baseline reactor neutrino experiment and extract the antineutrino spectra produced by the fission of major isotopes such as^(235)U,^(238)U,^(239)Pu,and^(241)Pu in the nuclear reactor.We present two training strategies for the model and compare them with the traditional X^(2) minimization method by applying them to the same set of pseudo-data corresponding to a total exposure of(2.9×5×1800)GW_(th)·tons·days.The results show that the FNN model not only converges faster and better during the fitting process but also achieves relative errors of less than 1%in the 2−8 MeV range in the extracted spectra,outperforming the X^(2) minimization method.The feasibility and superiority of this method were validated in the study. 展开更多
关键词 Reactor neutrinos Isotope antineutrino spectra Feedforward neural network
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A deep learning approach for enhanced degradation diagnostics of NMC lithium-ion batteries via impedance spectra
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作者 Yue Sun Rui Xiong +2 位作者 Peng Wang Hailong Li Fengchun Sun 《Journal of Energy Chemistry》 2025年第8期894-907,共14页
Electrochemical impedance spectroscopy(EIS)offers valuable insights into the dynamic behaviors of lithium-ion batteries,making it a powerful and non-invasive tool for evaluating battery health.However,EIS falls short ... Electrochemical impedance spectroscopy(EIS)offers valuable insights into the dynamic behaviors of lithium-ion batteries,making it a powerful and non-invasive tool for evaluating battery health.However,EIS falls short in quantitatively determining the degree of specific degradation modes,which are essential for improving battery lifespan.This study introduces a novel approach employing deep neural networks enhanced by an attention mechanism to identify the degree of degradation modes.The proposed method can automatically determine the most relevant frequency ranges for each degradation mode,which can link impedance characteristics to battery degradation.To overcome the limitation of scarce labeled experimental data,simulation results derived from mechanistic models are incorporated into the model.Validation results demonstrate that the proposed method could achieve root mean square errors below 3%for estimating loss of lithium inventory and loss of active material of the positive electrode,and below 4%for estimating loss of active material of the negative electrode while requiring only 25%of early-stage experimental degradation data.By integrating simulation results,the proposed method achieves a reduction in maximum estimation error ranging from 42.92%to 66.30%across different temperatures and operating conditions compared to the baseline model trained solely on experimental data. 展开更多
关键词 Lithium-ion battery Degradation diagnostics Impedance spectra Integration strategy Deep learning
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Kolmogorov-Arnold networks modeling of wall pressure wavenumber-frequency spectra under turbulent boundary layers
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作者 Zhiteng Zhou Yi Liu +1 位作者 Shizhao Wang Guowei He 《Theoretical & Applied Mechanics Letters》 2025年第2期115-121,共7页
The empirical models for wavenumber-frequency spectra of wall pressure are broadly used in the fast prediction of aerodynamic and hydrodynamic noise.However,it needs to fit the parameter using massive data and is only... The empirical models for wavenumber-frequency spectra of wall pressure are broadly used in the fast prediction of aerodynamic and hydrodynamic noise.However,it needs to fit the parameter using massive data and is only used for limited cases.In this letter,we propose Kolmogorov-Arnold networks(KAN)base models for wavenumber-frequency spectra of pressure fluctuations under turbulent boundary layers.The results are compared with DNS results.In turbulent channel flows,it is found that the KAN base model leads to a smooth wavenumber-frequency spectrum with sparse samples.In the turbulent flow over an axisymmetric body of revolution,the KAN base model captures the wavenumber-frequency spectra near the convective peak. 展开更多
关键词 Wavenumber-frequency spectra Kolmogorov-Arnold networks modeling Turbulent boundary layers
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Anharmonic and Damped Correction to Displaced Franck-Condon Factors for Simulating Molecular Absorption and Fluorescence Spectra
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作者 Chaoyuan Zhu 《Chinese Journal of Chemical Physics》 2025年第5期546-564,I0147,共20页
The anharmonic correction to displaced Franck-Condon(FC)factors introduces a first-order perturbative correction to the Huang-Rhys factors,enabling accurate simulation of vibronic spectra in the gas phase.In contrast,... The anharmonic correction to displaced Franck-Condon(FC)factors introduces a first-order perturbative correction to the Huang-Rhys factors,enabling accurate simulation of vibronic spectra in the gas phase.In contrast,the damped correction to displaced FC factors provides a non-perturbative modification to the Huang-Rhys factors for simulating vibronic spectra in solution,where the damped local-mode motions of the solute molecule effectively represent strong solute-solvent interactions.Practically,the damped FC method is implemented by transforming the mass-weighted unperturbed Hessian matrix(gas phase)into a perturbed Hessian matrix(solution phase)through effective scaling of atomic masses.The anharmonic FC method is applied to simulate the absorption and fluorescence spectra of the pyridine molecule.The results reveal an enhancement in absorption intensity and a corresponding weakening of fluorescence in the first excited state,which are in good agreement with experimental observations.The damped FC method is further employed to reproduce solvent-enhanced absorption and fluorescence spectra for perylene and carbazole molecules in solution.For perylene in benzene,a single-group mass-scaling parameter successfully reproduces the observed spectral enhancement.For carbazole in n-hexane,however,multiple-group mass-scaling parameters are required to capture the extremely enhanced spectral features.Overall,the present anharmonic and damped corrections to displaced Franck-Condon factors provide an analytically tractable and efficient framework for simulating vibronic spectra of large and complex molecular systems. 展开更多
关键词 Franck-Condon factors Molecular absorption and fluorescence spectra Huang-Rhys factors Solvent effects
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A time-dependent generalized Floquet calculation of the laser-induced lineshape in attosecond transient absorption spectra
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作者 Xu-Han Wang Di Zhao Peng-Bo Li 《Chinese Physics B》 2025年第11期359-367,共9页
We introduce a time-dependent generalized Floquet(TDGF)approach to calculate attosecond transient absorption spectra of helium atoms subjected to the combination of an attosecond extreme ultraviolet(XUV)pulse and a de... We introduce a time-dependent generalized Floquet(TDGF)approach to calculate attosecond transient absorption spectra of helium atoms subjected to the combination of an attosecond extreme ultraviolet(XUV)pulse and a delayed few-cycle infrared(IR)laser pulse.This TDGF approach provides a Floquet understanding of the laser-induced change of resonant absorption lineshape.It is analytically demonstrated that the phase shift of the time-dependent dipole moment that results in the lineshape changes consists of two components,the adiabatic laser-induced phase(LIP)due to the IR-induced Stark shifts of adiabatic Floquet states and the non-adiabatic phase correction due to the non-adiabatic IR-induced coupling between adiabatic Floquet states.Comparisons of the spectral lineshape calculated based on the TDGF approach with the results obtained with the LIP model[Phys.Rev.A 88033409(2013)]and the rotating-wave approximation(RWA)are presented for several typical cases,demonstrating that TDGF universally and accurately captures IR-induced lineshape changes.It is suggested that the LIP model works as long as the generalized adiabatic theorem[PRX Quantum 2030302(2021)]holds,and the RWA works when the higher-order IR-coupling effect in the formation of adiabatic Floquet states is neglectable. 展开更多
关键词 attosecond transient absorption spectra Floquet analysis non-adiabatic phase correction
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Optimization of the prompt fission neutron spectra of ^(239)Pu(n,f)via criticality benchmarking
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作者 Jia-Hao Chen Bo Yang +5 位作者 Qing-Gang Jia Rui Li Wen-Di Chen Hai-Rui Guo Wei-Li Sun Tao Ye 《Nuclear Science and Techniques》 2025年第9期139-149,共11页
Prompt fission neutron spectra(PFNS)have a significant role in nuclear science and technology.In this study,the PFNS for^(239)Pu are evaluated using both differential and integral experimental data.A method that lever... Prompt fission neutron spectra(PFNS)have a significant role in nuclear science and technology.In this study,the PFNS for^(239)Pu are evaluated using both differential and integral experimental data.A method that leverages integral criticality benchmark experiments to constrain the PFNS data is introduced.The measured central values of the PFNS are perturbed by constructing a covariance matrix.The PFNS are sampled using two types of covariance matrices,either generated with an assumed correlation matrix and incorporating experimental uncertainties or derived directly from experimental reports.The joint Monte Carlo transport code is employed to perform transport simulations on five criticality benchmark assemblies by utilizing perturbed PFNS data.Extensive simulations result in an optimized PFNS that shows improved agreement with the integral criticality benchmark experiments.This study introduces a novel approach for optimizing differential experimental data through integral experiments,particularly when a covariance matrix is not provided. 展开更多
关键词 Prompt fission neutron spectra Differential nuclear data Criticality benchmark Random sample Transport simulation
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Could Plant Height Compensate for Temporal and Spatial Limitations of Canopy Spectra for Inversion of Plant Nitrogen Accumulation in Rice?
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作者 WANG Xiaoke XU Guiling +7 位作者 FENG Yuehua SONG Zhengli GUO Yanjun Muhammad Usama LATIF LU Linya Somsana PHONENASAY XU Xiangjun CUI BingPing 《Rice science》 2025年第4期467-471,I0037-I0042,共11页
Recently,information acquired at the canopy top,such as spectral and textural data,has been widely used to estimate plant nitrogen(N)accumulation(PNA).The response of crops to N uptake involves not only changes in hor... Recently,information acquired at the canopy top,such as spectral and textural data,has been widely used to estimate plant nitrogen(N)accumulation(PNA).The response of crops to N uptake involves not only changes in horizontal canopy top information but also an increase in vertical plant height(PH).It remains unclear whether the fusion of spectral indices with PH can improve the estimation performance of PNA models based on spectral remote sensing across different growth stages. 展开更多
关键词 temporal limitations RICE nitrogen accumulation canopy top information spatial limitations plant height spectral remote sensing canopy spectra
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Characterization and recognition of three-dimensional excitation-emission matrix spectra of wastewater from six typical categories
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作者 Litao Kuang Rui Liu +4 位作者 Meng Jin Yaqiong Lan Yingying Su Yuan Zhao Lujun Chen 《Journal of Environmental Sciences》 2025年第11期206-219,共14页
In this study,we analyzed the characteristics of three-dimensional excitation-emission matrix spectra(EEMs)of 150 samples from five industrial wastewater types and domestic sewage to track water pollution sources effe... In this study,we analyzed the characteristics of three-dimensional excitation-emission matrix spectra(EEMs)of 150 samples from five industrial wastewater types and domestic sewage to track water pollution sources effectively.We then developed a recognition model for wastewater EEMs by establishing a feature dataset containing fluorescence peak values and parameters derived from EEMs,integrated with machine learning techniques.This model enables the rapid and precise identification of pollution sources.Our findings suggest that although the EEMs of the sixwastewater categories are distinct,visual differentiation is challenging.This was confirmed by cosine similarity assessments,showing some samples with low within-group(<0.8)and high between-group(>0.95)similarities.Despite significant variations in EEMs features acrosswastewater categories,identifying specific pollutants remains difficult,especially for pulp mills and leather effluents.Among the tested classification algorithms,Support Vector Machine(SVM)achieved the highest performance with91.7%accuracy,94%precision,91%recall,and 92%F_(1)-score,outperforming K-Nearest Neighbors and Partial Least Squares Discriminant Analysis.The SVM significantly improved identification accuracy for pulpmill and leather processing wastewaters compared to other models.To enhance identification accuracy,further exploration of EEMs features and expanding the training dataset are recommended.Combining EEMs features with machine learning presents a promising method for improvingwater pollution supervision and source tracing in environmental management practices. 展开更多
关键词 Excitation-emission-matrix spectra Support vector machine K-nearest neighbor Industrial wastewater Domestic sewage Partial least squares discriminant analysis
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Fresenius COM. TEC与Spectra OPTIA采集外周血造血干细胞的特点及其临床应用
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作者 李少文 朱展鸿 +4 位作者 高旖鑫 王刚 郭楚霞 陆志刚 彭永正 《联勤军事医学》 2024年第12期1064-1068,共5页
目的 比较Fresenius COM.TEC与Spectra OPTIA两种血细胞分离机在采集捐献者外周血造血干细胞时的采集效率、采集物特性及对捐献者后续的影响。方法 回顾性分析2020-03/2023-10月在作者医院接受外周血造血干细胞采集的217例健康捐献者资... 目的 比较Fresenius COM.TEC与Spectra OPTIA两种血细胞分离机在采集捐献者外周血造血干细胞时的采集效率、采集物特性及对捐献者后续的影响。方法 回顾性分析2020-03/2023-10月在作者医院接受外周血造血干细胞采集的217例健康捐献者资料,包括采集前后捐献者的血常规、电解质、采集过程中的相关参数、不良反应情况和采集物单个核细胞数及CD34^(+)细胞数。结果 Fresenius COM.TEC与Spectra OPTIA在采集外周血造血干细胞后对捐献者的血常规和电解质指标、采集过程中的循环血量、采集效率、采集物的单个核细胞数、CD34^(+)细胞数、采集过程及采集后不良反应发生率比较差异无统计学意义(P>0.05),但在血液保存液用量上,Fresenius COM.TEC比Spectra OPTIA更少(P<0.05)。而Fresenius COM.TEC采集的产物中,白细胞计数、红细胞计数、红细胞比容、血小板计数及中性粒细胞计数均显著高于Spectra OPTIA(P均<0.05)。结论 Fresenius COM.TEC与Spectra OPTIA两种血细胞分离机均能有效且安全地完成外周血造血干细胞的采集任务。在实际应用中,可根据捐献者的具体特点选择合适的机器或调整动员方案,以达到最佳的采集效果。 展开更多
关键词 Fresenius COM.TEC spectra OPTIA 外周血造血干细胞 血细胞分离机 CD34^(+)细胞
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3D reverse-time migration for pure P-wave in orthorhombic media 被引量:1
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作者 Ying-Hui Liu Jian-Ping Huang +2 位作者 Liang Chen Qiang Mao Kun Tian 《Petroleum Science》 CSCD 2024年第6期3937-3950,共14页
Compared with the transverse isotropic(TI)medium,the orthorhombic anisotropic medium has both horizontal and vertical symmetry axes and it can be approximated as a set of vertical fissures developed in a group of hori... Compared with the transverse isotropic(TI)medium,the orthorhombic anisotropic medium has both horizontal and vertical symmetry axes and it can be approximated as a set of vertical fissures developed in a group of horizontal strata.Although the full-elastic orthorhombic anisotropic wave equation can accurately simulate seismic wave propagation in the underground media,a huge computational cost is required in seismic modeling,migration,and inversion.The conventional coupled pseudo-acoustic wave equations based on acoustic approximation can be used to significantly reduce the cost of calculation.However,these equations usually suffer from unwanted shear wave artifacts during wave propagation,and the presence of these artifacts can significantly degrade the imaging quality.To solve these problems,we derived a new pure P-wave equation for orthorhombic media that eliminates shear wave artifacts while compromising computational efficiency and accuracy.In addition,the derived equation involves pseudo-differential operators and it must be solved by 3D FFT algorithms.In order to reduce the number of 3D FFT,we utilized the finite difference and pseudo-spectral methods to conduct 3D forward modeling.Furthermore,we simplified the equation by using elliptic approximation and implemented 3D reverse-time migration(RTM).Forward modeling tests on several homogeneous and heterogeneous models confirm that the accuracy of the new equation is better than that of conventional methods.3D RTM imaging tests on three-layer and SEG/EAGE 3D salt models confirm that the ORT media have better imaging quality. 展开更多
关键词 Orthorho mbicmedia ANISOTROPIC Pure p-wave equation 3D reverse-time migration Graphic processing unit acceleration
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Investigation Study of Structure Real Load Spectra Acquisition and Fatigue Life Prediction Based on the Optimized E cient Hinging Hyperplane Neural Network Model 被引量:1
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作者 Lin Zhu Benao Xing +2 位作者 Xingbao Li Min Chen Minping Jia 《Chinese Journal of Mechanical Engineering》 CSCD 2024年第6期628-648,共21页
In the realm of engineering practice,various factors such as limited availability of measurement data and complex working conditions pose significant challenges to obtaining accurate load spectra.Thus,accurately predi... In the realm of engineering practice,various factors such as limited availability of measurement data and complex working conditions pose significant challenges to obtaining accurate load spectra.Thus,accurately predicting the fatigue life of structures becomes notably arduous.This paper proposed an approach to predict the fatigue life of structure based on the optimized load spectra,which is accurately estimated by an efficient hinging hyperplane neural network(EHH-NN)model.The construction of the EHH-NN model includes initial network generation and parameter optimization.Through the combination of working conditions design,multi-body dynamics analysis and structural static mechanics analysis,the simulated load spectra of the structure are obtained.The simulated load spectra are taken as the input variables for the optimized EHH-NN model,while the measurement load spectra are used as the output variables.The prediction results of case structure indicate that the optimized EHH-NN model can achieve the high-accuracy load spectra,in comparison with support vector machine(SVM),random forest(RF)model and back propagation(BP)neural network.The error rate between the prediction values and the measurement values of the optimized EHH-NN model is 4.61%.In the Cauchy-Lorentz distribution,the absolute error data of 92%with EHH-NN model appear in the intermediate range of±1.65%.Also,the fatigue life analysis is performed for the case structure,based on the accurately predicted load spectra.The fatigue life of the case structure is calculated based on the comparison between the measured and predicted load spectra,with an accuracy of 93.56%.This research proposes the optimized EHH-NN model can more accurately reflect the measurement load spectra,enabling precise calculation of fatigue life.Additionally,the optimized EHH-NN model provides reliability assessment for industrial engineering equipment. 展开更多
关键词 Efficient hinging hyperplane neural network model ANOVA decomposition Load spectra optimization Optimal parameter Fatigue life prediction
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Elastoplastic bridge deck response spectra of high-speed railway simply-supported girder bridge with CRTS Ⅱ track system 被引量:1
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作者 LIU Bo-lun HE Chang +2 位作者 LAI Zhi-peng JIANG Li-zhong LI Dong-ping 《Journal of Central South University》 CSCD 2024年第11期4174-4186,共13页
The seismic damage to ancillary facilities on high-speed railway(HSR)bridges can affect the normal movement of trains.To propose the bridge deck acceleration response spectra of the typical HSR simply-supported girder... The seismic damage to ancillary facilities on high-speed railway(HSR)bridges can affect the normal movement of trains.To propose the bridge deck acceleration response spectra of the typical HSR simply-supported girder bridge for simplifying the seismic responses analysis of the facilities on bridges,the finite element models of the HSR multi-span simply-supported girder bridges with CRTSII track were established,and the numerical model was validated by tests.Besides,the effects of the span number,peak ground acceleration(PGA),pier height on the seismic acceleration and response spectra of the bridge deck were investigated.Afterward,the bridge acceleration amplification factor curves and bridge deck response spectra with different PGAs and pier heights were obtained.The formula for bridge deck acceleration amplification factor,with a 95%guarantee rate,was fitted.Moreover,the finite element models of the overhead contact lines(OCL)mounted on rigid base and bridges were established to validate the fitted formula.The results indicated that the maximum seismic acceleration response is in the midspan of the beam.The proposed formula for the bridge deck acceleration response spectra can be used to analyze the earthquake response of the OCL and other ancillary facilities on HSR simply-supported girder bridges.The bridge deck acceleration response spectra are conservative in terms of structural safety and can significantly improving the analysis efficiency. 展开更多
关键词 high-speed railway CRT SⅡtrack-bridge system bridge deck acceleration response spectra overhead contact line seismic amplification effect
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Remnant Paleoproterozoic Subduction or Lithospheric Drip Initiation at the Yilgarn Craton Margin:Constraints from P-wave Tomography
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作者 XU Xiaobing WANG Kun +2 位作者 YANG Dinghui ZHAO Liang YUAN Huaiyu 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第S01期72-74,共3页
The Paleoproterozoic was a critical time in whether modern-style plate tectonics had become globally dominant(e.g.,Wan et al.,2020).The Capricorn Orogen witnessed the assembly of the Pilbara and Yilgarn Cratons and an... The Paleoproterozoic was a critical time in whether modern-style plate tectonics had become globally dominant(e.g.,Wan et al.,2020).The Capricorn Orogen witnessed the assembly of the Pilbara and Yilgarn Cratons and an exotic microcontinent,the Glenburgh Terrane,to form the West Australia Craton(WAC)through two collisional orogenic events,the 2215–2145 Ma Ophthalmian and 2005–1950 Ma Glenburgh Orogenies(Johnson et al.,2013;Fig.1).Compared to other Proterozoic orogenic belts in Australia,the Capricorn Orogen preserves‘complete'opposing continental margin successions,together with intervening arc fragments associated with oceanic closure and foreland basins associated with collisional loading(Cawood et al.,2009). 展开更多
关键词 p-wave tomography finite-frequency method SUBDUCTION Capricorn Orogen
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Deep learning for determining pure isotropic proton spectra from solidstate spectra
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作者 Mengjie Qiu Zhong Chen Yanqin Lin 《Magnetic Resonance Letters》 2024年第1期63-64,共2页
Recently,an article on ^(1)H solid-state NMR spectra was published,in which the authors proposed a deep learning approach to infer the pure isotropic proton NMR spectra obtained at an infinite magic angle spinning(MAS... Recently,an article on ^(1)H solid-state NMR spectra was published,in which the authors proposed a deep learning approach to infer the pure isotropic proton NMR spectra obtained at an infinite magic angle spinning(MAS)rate.This approach even allowed to obtain,by far,the best resolved ^(1)H spectra of molecular solids[1](https://doi.org/10.1002/anie.202216607).Deep learning based artificial intelligence is developing rapidly,and its application is deepening.Currently,there are many applications of deep learning in the field of magnetic resonance,such as the reconstruction of the under-sampled multidimensional spectra[2-4],the deconvolution of two-dimensional NMR spectra[5]and noise suppression and weak peak retrial[6],etc. 展开更多
关键词 spectra ISOTROPIC STATE
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