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刚度特征值对摇摆墙-框架结构抗震韧性影响分析

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沈阳建筑大学学报(自然科学版) 2025年第1期41卷 10-19页

作者：苏醒阎石高跃峰夏伟军沈阳建筑大学土木工程学院辽宁沈阳110068 烟台市芝罘区综合行政执法局山东烟台264000 沈阳新湖房地产有限公司辽宁沈阳110020

研究刚度特征值λ对摇摆墙-框架结构弹性协同工作与弹塑性抗震韧性的影响规律。建立了静力作用下摇摆墙-框架(RWMF)结构的简化力学模型并进行求解,得到λ值对内力和侧移的基本影响规律。利用ABAQUS建立了6个具有不同λ值的RWMF有限元模... 详细信息

研究刚度特征值λ对摇摆墙-框架结构弹性协同工作与弹塑性抗震韧性的影响规律。建立了静力作用下摇摆墙-框架(RWMF)结构的简化力学模型并进行求解,得到λ值对内力和侧移的基本影响规律。利用ABAQUS建立了6个具有不同λ值的RWMF有限元模型,并进行动力弹塑性分析,研究λ值对其层间侧移集中性、塑性铰分布和出铰率等韧性指标的影响规律,并基于以上指标对λ值进行优化。在弹性状态下,减小λ值可以使RWMF变形均匀且受力更加合理;在弹塑性状态下,减小λ值可有效避免框架的层屈服破坏,使结构变为整体型破坏模式。当λ值在4.5~6.5时,目标函数z(λ)取得最优解。λ值的优选范围与RWMF结构的内力与变形规律对指导RWMF结构的初步设计具有重要意义。

关键词：摇摆墙-框架结构刚度特征值λ 协同工作动力弹塑性分析抗震韧性

Global Freshwater Storage Capability across Time Scales in the GRACE Satellite Era

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Advances in Atmospheric Sciences 2021年第6期38卷 905-917页

作者： Enda zHU xing YUAN Key Laboratory of Regional Climate-Environment for Temperate East Asia(RCE-TEA) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China School of Hydrology and Water Resources Nanjing University of Information Science and TechnologyNanjing 210044China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

Freshwater is recharged mainly by rainfall and stored inland for a period of time,which is directly affected by its storage *** storage capability of river basins has different spatiotemporal features that are important for the predictability of freshwater ***,the estimation of freshwater storage capability(FSC)remains a challenge due to the lack of observations and quantification ***,we use a metric that characterizes hydrological“inertia”after rainfalls to analyze FSC over the 194 largest global major river basins based on satellite observations from the Gravity Recovery and Climate Experiment(GRACE)and simulations from the Community Land Model version 5(CLM5).During 2003–16,the global land was observed to retain 28%of precipitation after one month based on GRACE observations,and the simulation depicts that the retained proportions decrease from 42%after one day to 26%after one month,with smaller FSC partly attributed to wetter conditions and higher vegetation *** root zone contributes about 40%to the global land FSC on daily to monthly time *** the time scale increases,the contribution from the surface soil decreases from 26%to 14%,while the contribution from the deep soil increases from 4%to 10%.Snow contributes over 20%of land FSC,especially over high *** six decades of CLM5 long-term simulations,it is revealed that the change of FSC in most basins is related to internal climate *** FSC of river basins which displays the proportion of precipitation retained on land is worthy of further attention regarding the predictability of water resources.

关键词： freshwater GRACE land surface model soil moisture climate variability storage capability

Photon polarization effects in polarized electron–positron pair production in a strong laser field

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Matter and Radiation at Extremes 2022年第1期7卷 5-14页

作者： Ya-Nan Dai Bai-Fei Shen Jian-xing Li Rashid Shaisultanov Karen z.Hatsagortsyan Christoph H.Keitel Yue-Yue Chen Department of Physics Shanghai Normal UniversityShanghai 200234China State Key Laboratory of High Field Laser Physics and CAS Center for Excellence in Ultra-intense Laser Science Shanghai Institute of Optics and Fine Mechanics(SIOM)Chinese Academy of Sciences(CAS)Shanghai 201800China School of Physics Xi’an Jiaotong UniversityXi’an 710049China Max-Planck-Institut fur Kernphysik Saupfercheckweg 169117 HeidelbergGermany Helmholtz-zentrum Dresden-Rossendorf Bautzner Landstraße 40001328 DresdenGermany

Deep understanding of the impact of photon polarization on pair production is essential for the efficient generation of laser-driven polarized positron beams and demands a complete description of polarization effects in strong-field QED *** fully polarization-resolved Monte Carlo simulations,we investigate correlated photon and electron(positron)polarization effects in the multiphoton Breit–Wheeler pair production process during the interaction of an ultrarelativistic electron beam with a counterpropagating elliptically polarized laser *** show that the polarization of e−e+pairs is degraded by 35%when the polarization of the intermediate photon is resolved,accompanied by an∼13%decrease in the pair ***,in this case,the polarization direction of energetic positrons at small deflection angles can even be reversed when high-energy photons with polarization parallel to the laser electric field are involved.

关键词： polarized positron resolved

Simulation of a ground-mounted prism in ABL flow using LES:on overview of error metrics and distribution

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Advances in Aerodynamics 2023年第1期5卷 167-185页

作者： Jin xing Department of Civil ChemicalEnvironmentaland Materials Engineering(DICAM)University of BolognaViale del Risorgimento 2Bologna 40136Italy

The accuracy of wind loading predictions using Large Eddy Simulation(LES)is usually influenced by numerous model parameters,which can influence the obtained *** validation of numerical simulations with traditional Wind Tunnel Test(WTT)is still an important task,necessary to increase our a priori knowledge of possible inaccuracies and set up mitigation *** this study,LES is used to simulate the wind fields around an isolated model high-rise building,under seven wind attack angles and vali-dated with WTT *** influence of various settings and parameters on the model performance is *** the angle of attack showing higher inaccuracy,different mesh refinement strategies and turbulence models are *** indicate that LES can accurately predict the mean and local maxima of the pressure coefficients for both perpendicular and skew wind attack angles,as well as reproduce global forces and their envelopes with very good ***,pronounced errors are found in the prediction of the pressure coefficient standard deviation and the local *** highest deviations between LES and WTT are found close to the leading edge in cor-respondence of flow separations which are observed in WTT and not in LES for skew *** addition of boundary layer cells and the use of different subgrid models have very limited effectiveness in modifying the obtained results for the analysed case.

关键词： Wind loading CFD High-rise buildings Large eddy simulation Aerodynamics

Improving the second-tier classification of methylmalonic acidemia patients using a machine learning ensemble method

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World Journal of Pediatrics 2024年第10期20卷 1090-1101页

作者： zhi-xing zhu Georgi zGenchev Yan-Min Wang Wei Ji Yong-Yong Ren Guo-Li Tian Sira Sriswasdi Hui Lu Shanghai Engineering Research Center for Big Datain Pediatric Precision Medicine Center for BiomedicalInformaticsShanghai Children’s HospitalSchoolof MedicineShanghai Jiao Tong UniversityShanghaiChina Center of Excellence in Computational Molecular Biology Faculty of MedicineChulalongkorn UniversityBangkokThailand Newborn Screening Center Shanghai Children’s HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghaiChina SJTU-Yale Joint Center for Biostatistics and Data Science National Center for Translational MedicineShanghai JiaoTong UniversityShanghaiChina Center for Artifcial Intelligence in Medicine ResearchAfairsFaculty of MedicineChulalongkorn UniversityBangkokThailand State Key Laboratory of Microbial Metabolism JointInternational Research Laboratory of Metabolic&Developmental SciencesDepartment of Bioinformaticsand BiostatisticsSchool of Life Sciences and BiotechnologyShanghai Jiao Tong UniversityShanghaiChina

Introduction Methylmalonic acidemia(MMA)is a disorder of autosomal recessive inheritance,with an estimated prevalence of 1:50,***-tier clinical diagnostic tests often return many false positives[fve false positive(FP):one true positive(TP)].In this work,our goal was to refne a classifcation model that can minimize the number of false positives,currently an unmet need in the upstream diagnostics of *** We developed machine learning multivariable screening models for MMA with utility as a secondary-tier tool for false positives *** utilized mass spectrometry-based features consisting of 11 amino acids and 31 carnitines derived from dried blood samples of neonatal patients,followed by additional ratio feature *** selection strategies(selection by flter,recursive feature elimination,and learned vector quantization)were used to determine the input set for evaluating the performance of 14 classifcation models to identify a candidate model set for an ensemble model *** Our work identifed computational models that explore metabolic analytes to reduce the number of false positives without compromising *** best results[area under the receiver operating characteristic curve(AUROC)of 97%,sensitivity of 92%,and specifcity of 95%]were obtained utilizing an ensemble of the algorithms random forest,C5.0,sparse linear discriminant analysis,and autoencoder deep neural network stacked with the algorithm stochastic gradient boosting as the *** model achieved a good performance trade-of for a screening application with 6%false-positive rate(FPR)at 95%sensitivity,35%FPR at 99%sensitivity,and 39%FPR at 100%*** The classifcation results and approach of this research can be utilized by clinicians globally,to improve the overall discovery of MMA in pediatric *** improved method,when adjusted to 100%precision,can be used to further inform the diagnostic process journey of MMA and help r

关键词： Machine learning Methylmalonic acidemia Second-tier test Stacking

Differential quadrature time element method for structural dynamics

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Acta Mechanica Sinica 2012年第3期28卷 782-792页

作者： Yu-Feng xing Jing Guo The Solid Mechanics Research Center Beihang University100191 BeijingChina

An accurate and efficient differential quadrature time element method （DQTEM） is proposed for solving ordi- nary differential equations （ODEs）, the numerical dissipation and dispersion of DQTEM is much smaller than that of the direct integration method of single/multi steps. Two methods of imposing initial conditions are given, which avoids the tediousness when derivative initial conditions are imposed, and the numerical comparisons indicate that the first method, in which the analog equations of initial displacements and velocities are used to directly replace the differential quadra- ture （DQ） analog equations of ODEs at the first and the last sampling points, respectively, is much more accurate than the second method, in which the DQ analog equations of initial conditions are used to directly replace the DQ analog equations of ODEs at the first two sampling points. On the contrary to the conventional step-by-step direct integration schemes, the solutions at all sampling points can be obtained simultaneously by DQTEM, and generally, one differential quadrature time element may be enough for the whole time domain. Extensive numerical comparisons validate the effi- ciency and accuracy of the proposed method.

关键词： Differential quadrature rule Direct integrationmethod Time element Phase error. Artificial damping

Synthesis,Structure and Hydrogenation Property of trans-PdCl_(2){Ph_(2)P[o-C_(6)H_(4)CH(OC_(2)H_(5))_(2)]}_(2)

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Chemical Research in Chinese Universities 1997年第4期13卷 117-120页

作者： Xu, PP Gao, JX zhou, zH Wang, Jz Chen, z Hu, Sz Wan, HL XIAMEN UNIV DEPT CHEMSTATE KEY LAB PHYS CHEM SOLID SURFACEXIAMEN 361005PEOPLES R CHINA XIAMEN UNIV INST PHYS CHEMXIAMEN 361005PEOPLES R CHINA

Ｓｙｎｔｈｅｓｉｓ，ＳｔｒｕｃｔｕｒｅａｎｄＨｙｄｒｏｇｅｎａｔｉｏｎＰｒｏｐｅｒｔｙｏｆｔｒａｎｓ┐ＰｄＣｌ２｛Ｐｈ２Ｐ［ｏ┐Ｃ６Ｈ４ＣＨ（ＯＣ２Ｈ５）２］｝２＊ＸＵＰｉａｎ－ｐｉａｎ，ＧＡＯＪｉｎｇ－ｘｉｎｇ＊＊... 详细信息

Ｓｙｎｔｈｅｓｉｓ，ＳｔｒｕｃｔｕｒｅａｎｄＨｙｄｒｏｇｅｎａｔｉｏｎＰｒｏｐｅｒｔｙｏｆｔｒａｎｓ┐ＰｄＣｌ２｛Ｐｈ２Ｐ［ｏ┐Ｃ６Ｈ４ＣＨ（ＯＣ２Ｈ５）２］｝２＊ＸＵＰｉａｎ－ｐｉａｎ，ＧＡＯＪｉｎｇ－ｘｉｎｇ＊＊，ＺＨＯＵＺｈａｏ－ｈｕｉ，ＷＡＮ...

关键词： Palladium complex Hydrogenation Crystal structure

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投资者情绪、有限套利与股票收益率

攀枝花学院学报 2025年第1期42卷 61-72页

作者：邢瑞何朝林安徽工程大学数理与金融学院安徽芜湖241000

本文从行为金融学的角度出发,以2010—2022年间我国上证A股为研究样本,采用单因素投资组合分析、双因素投资组合分析和固定效应模型等实证方法研究投资者情绪、有限套利对股票收益率的影响及其内在相互作用机制。研究发现:投资者情绪和... 详细信息

本文从行为金融学的角度出发,以2010—2022年间我国上证A股为研究样本,采用单因素投资组合分析、双因素投资组合分析和固定效应模型等实证方法研究投资者情绪、有限套利对股票收益率的影响及其内在相互作用机制。研究发现:投资者情绪和有限套利与股票收益率之间具有显著的正相关关系,这种关系在控制公司规模、资产负债率、资产收益率、amihud非流动性指标和交易量后仍稳健存在。进一步发现,投资者情绪与有限套利之间存在双向加剧效应:投资者情绪加剧有限套利对股票收益率的影响,有限套利加剧投资者情绪对股票收益率的影响,并且投资者情绪和有限套利程度的高低造成的加剧效应也有所不同,具体表现为在投资者情绪和有限套利程度较高的样本公司中这种加剧效应更为明显。

关键词：投资者情绪有限套利股票收益率投资组合双向加剧效应

Generation of arbitrarily polarized GeV lepton beams via nonlinear Breit-Wheeler process

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Fundamental Research 2022年第4期2卷 539-545页

作者： Kun Xue Ren-Tong Guo Feng Wan Rashid Shaisultanov Yue-Yue Chen zhong-Feng Xu Xue-Guang Ren Karen z.Hatsagortsyan Christoph H.Keitel Jian-xing Li Ministy of Education Key Laboratory for Noneulbrium Synthesis and Modulatin of Condensed Mater Shaanxi ProvinceKey Laboratory ofQuantum Infomation and Quantum Optoelectronic DevicesSchool of PhysicsXi'an Jiaotong UniversityXi'an 710049China Max-Planck-Instut fir Kermphysk Saupfercheckweg 1Heidelberg 69117Germany Helmholtz-zentrum Dresden-Rosendorf Bautiner Landstrage 400Dresden 01328Germany Department of Physics Shanghai Normal UniversityShanghai 200234China

Generation of arbitrarily spin-polarized electron and positron beams has been investigated in the single-shot interaction of high-energy polarized r-photons with an ultraintense asymmetric laser pulse via nonlinear Breit-Wheeler pair *** develop a fully spin-resolved semi-classical Monte Carlo method to describe the pair creation and *** the considered general setup,there are two sources of the polarization of created pairs:the spin angular momentum transfer from the polarized parent-photons,as well as the asymmetry and polarization of the driving laser *** allows to develop a highly sensitive tool to control the polarization of created electrons and ***,dense GeV lepton beams with average polarization degree up to about 80%,adjustable continuously between the transverse and longitudinal components,can be obtained by our all-optical method with currently achievable laser facilities,which could find an application as injectors of the polarized e^(+)e^(-)collider to search for new physics beyond the Standard Model.

关键词： Nonlinear Breit-Wheeler pair production Spin polarization Polarized positron beam Polarized e^(+)e^(-)collider