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Journal of.Computer and Communications 2017年第14期5卷 76-85页

作者： D. Wang X. Luo f. yuan N. Podhorszki Environmental Science Division Oak Ridge National Laboratory Oak Ridge TN USA Department of.Computer Science and Electric Engineering University of Tennessee Knoxville TN USA Computer Science and Mathematics Division Oak Ridge National Laboratory Oak Ridge TN USA

This paper presents a generic procedure to implement a scalable and high perf.rmance data analysis f.amework f.r large-scale scientif.c simulation within an in-situ inf.astructure. It demonstrates a unique capability f.r global Earth system simulations using advanced computing technologies (i.e., automated code analysis and instrumentation), in-situ inf.astructure (i.e., ADIOS) and big data analysis engines (i.e., SciKit-learn). This paper also includes a usef.l case that analyzes a globe Earth System simulations with the integration of.scalable in-situ inf.astructure and advanced data processing package. The in-situ data analysis f.amework can provides new insights on scientif.c discoveries in multiscale modeling paradigms.

关键词： In-Situ Data Analysis Source Code Analysis Data Staging ADIOS Earth System Model Machine Learning SciKit-Learn E3SM

The origin and evolution of.Earth's nitrogen

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National Science Review 2024年第6期11卷 56-75页

作者： yuan Li State Key Laboratory of.Isotope Geochemistry Guangzhou Institute of GeochemistryChinese Academy of Sciences Bayerisches Geoinstitut Universit?t Bayreuth

Nitrogen is a vital element f.r lif. on Earth. Its cycling between the surf.ce(atmosphere + crust) and the mantle has a prof.und inf.uence on the atmosphere and climate. However, our understanding of.the origin and evolution of.Earth's nitrogen is still incomplete. This review presents an overview of.the current understanding of.Earth's nitrogen budget and the isotope composition of.dif.erent reservoirs, laboratory constraints on deep nitrogen geochemistry, and our understanding of.the origin of.Earth's nitrogen and the deep nitrogen cycle through plate subduction and volcanism. The Earth may have acquired its nitrogen heterogeneously during the main accretion phase, initially f.om reduced, enstatite-chondrite-like impactors,and subsequently f.om increasingly oxidized impactors and minimal CI-chondrite-like materials. Like Earth's surf.ce, the mantle and core are also signif.cant nitrogen reservoirs. The nitrogen abundance and isotope composition of.these three reservoirs may have been f.ndamentally established during the main accretion phase and have been insignif.cantly modif.ed af.erwards by the deep nitrogen cycle, although there is a net nitrogen ingassing into Earth's mantle in modern subduction zones. However, it is estimated that the early atmosphere of.Earth may have contained ～1.4 times the present-day atmospheric nitrogen(PAN),with ～0.4 PAN being sequestered into the crust via biotic nitrogen f.xation. In order to gain a better understanding of.the origin and evolution of.Earth's nitrogen, directions f.r f.ture research are suggested.

关键词： nitrogen isotopes silicate Earth atmosphere magma ocean

Robustness of.the octupole collectivity in 144Ba within the cranking covariant density f.nctional theory in 3D lattice

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Nuclear Science and Techniques 2024年第8期35卷 124-131页

作者： Ze‑Kai Li yuan‑yuan Wang Mathematics and Physics Department North China Electric Power UniversityBeijing 102206China Hebei Key Laboratory of.Physics and Energy Technology North China Electric Power UniversityBaoding 071000China

The octupole def.rmation and collectivity in octupole double-magic nucleus 144Ba are investigated using the Cranking covariant density f.nctional theory in a three-dimensional lattice *** reduced B(E3)transition probability is implemented f.r the f.rst time in semiclassical approximation based on the microscopically calculated electric octupole *** available data,including the I-ωrelation and electric transitional probabilities B(E2)and B(E3)are well ***,it is shown that the ground state of.144Ba exhibits axial octupole and quadrupole def.rmations that persist up to high spins(I≈24h).

关键词： Octupole collectivity Cranking covariant density f.nctional theory Rotational spectrum Electric transitional probabilities

Collective Molecular Machines: Multidimensionality and Reconf.gurability

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Nano-Micro Letters 2024年第8期16卷 309-340页

作者： Bin Wang yuan Lu Department of.Chemical Engineering Tsinghua UniversityBeijing 100084People’s Republic of China Key Laboratory of.Industrial Biocatalysis Ministry of EducationTsinghua UniversityBeijing 100084People’s Republic of China

Molecular machines are key to cellular activity where they are involved in converting chemical and light energy into ef.icient mechanical *** the last 60 years,designing molecular structures capable of.generating unidirectional mechanical motion at the nanoscale has been the topic of.intense *** progress has been made,attributed to advances in various f.elds such as supramolecular chemistry,biology and nanotechnology,and ***,individual molecular machines are only capable of.producing nanometer work and generally have only a single *** order to address these problems,collective behaviors realized by integrating several or more of.these individual mechanical units in space and time have become a new *** this review,we comprehensively discuss recent developments in the collective behaviors of.molecular *** particular,collective behavior is divided into two *** is the appropriate integration of.molecular machines to ef.iciently amplif. molecular motions and def.rmations to construct novel f.nctional *** other is the construction of.swarming modes at the supramolecular level to perf.rm nanoscale or microscale *** discuss design strategies f.r both modes and f.cus on the modulation of.f.atures and ***,in order to address existing challenges,the idea of.transf.rring experience gained in the f.eld of.micro/nano robotics is presented,of.ering prospects f.r f.ture developments in the collective behavior of.molecular machines.

关键词： Molecular machines Collective control Collective behaviors DNA Biomolecular motors

Global adaptive output-f.edback tracking with prescribed perf.rmance f.r uncertain nonlinear systems

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Science China(Inf.rmation Sciences) 2024年第5期67卷 150-164页

作者： yuan WANG Yungang LIU School of.Control Science and Engineering Shandong University

At present, one typical control strategy f.r guaranteeing transient and steady-state perf.rmance is f.nnel control and prescribed perf.rmance control. The strategy f.atures completely discarding the system nonlinearities, even if.they are completely known and available. Such an intrinsic f.ature requires the controller to produce a larger control ef.ect to eliminate the negative impact caused by the high nonlinearities, leading to a conservative controller. In this paper, we f.lly take advantage of.known inf.rmation on nonlinearities in control design, instead of.completely discarding it as done in f.nnel control. Particularly, we leverage adaptive techniques(i.e., high-gain dynamic compensation) to deal with unknown system nonlinearities. Meanwhile, we integrate the tools of.output f.edback, tracking control, and the perf.rmance *** such, an adaptive output-f.edback scheme is developed f.r global tracking with spatiotemporal perf.rmance specif.cations: arbitrarily given tracking accuracy and accuracy-ensured time. A simulation example supports the developed approach.

关键词： uncertain nonlinear systems output f.edback prescribed perf.rmance unknown control direction dynamic high gain global tracking

Theoretical study on the synergistic mechanism of.f.–Mn in sodium-ion batteries

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Particuology 2024年第10期93卷 284-290页

作者： Yang You Mingliang yuan School of.Mineral Processing and Bioengineering Central South UniversityChangsha410083China

This article conducts f.rst-principles calculations to initially explore the construction of.two conf.gurations,Naf.O_(2)(Nf.)and NaMnO_(2)(NMO),and studies the mixing enthalpies under dif.erent f.–Mn *** results indicate that Naf.3/8Mn5/8O_(2)(Nf.O)exhibits the most thermodynamically stable *** calculations on the mixing enthalpies and volume changes during the sodium extraction process f.r Nf.,NMO,and Nf.O conf.gurations are presented,along with the partial density of.states(PDOS)and Bader charges of.transition metals(TM)and *** calculations reveal the synergistic mechanism of.f. and *** and Mn can engage in more complex electron exchanges during sodium extraction,optimizing the internal electron density distribution and overall charge balance,thereby stabilizing the crystal structure and reducing the migration of.f.^(3+)to the sodium layers during deep sodium *** interaction between f.’s 3d electrons and Mn’s 3d electrons through the shared oxygen atoms’2p orbitals occurs in the f.–Mn–O *** interaction can lead to a rebalancing of.the electron density around Mn³⁺atoms,mitigating the asymmetric electron density distribution caused by the d4 conf.guration of.the lone Mn³⁺and suppressing the Jahn-Teller ef.ect of.Mn^(3+).Moreover,the synergistic ef.ects between f. and Mn can provide a more balanced charge distribution,reducing extreme changes to the charge state of.oxygen atoms and decreasing the irreversible oxygen release caused by anionic redox reactions during deep sodium extraction,thereby enhancing the material’s *** in-depth study of.the interaction mechanism at the microscopic level when co-doping f. and Mn of.ers valuable insights f.r the rational design and development of.high-perf.rmance cathode materials.

关键词： f.rst-principles calculations Sodium-ionbatteries Layered oxides Naf._(3/8)Mn_(3/8)O_(2)

Paleomagnetism and paleoclimate change in the South China Sea since the late Pleistocene

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Acta Oceanologica Sinica 1992年第4期11卷 573-581页

作者： Xidong Chen, Douglas f. Williams, yuan Youren, Wang Baogui, Tang Xianzan, f.n Shiqing and Liu Zongyang 1. University of.South Carolina, USA2. South China Sea Institute of.Oceanology, Academia Sinica, Guangzhou 510301, China

Signal processing techniques of.cross-correlation, power spectral analysis and cross-power spectral analysis are used to determine the relationships between paleomagnetic properties and the oxygen isotope record of.the South China Sea during the late Pleistocene. On the basis of.correlation tests between the δ18O time series of.cores V3 and A15 with the paleomagnetic properties of.core SCS01, f.ve events of.susceptibility and intensity of.natural remanent magnetization are identif.ed as glacial events corresponding to δ18O positive events. The magnetic properties of.the sediments which are independent of.the geomagnetic f.eld are sensitive climatic indicators which have f.equencies corresponding to the Milankovitch orbital parameters.

关键词： Paleomagnetism and paleoclimate change in the South China Sea since the late Pleistocene SCS

MAUN:Memory-Augmented Deep Unf.lding Network f.r Hyperspectral Image Reconstruction

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IEEE/CAA Journal of.Automatica Sinica 2024年第5期11卷 1139-1150页

作者： Qian Hu Jiayi Ma yuan Gao Junjun Jiang Yixuan yuan Electronic Inf.rmation School Wuhan UniversityWuhan 430072China School of.Computer Science and Technology Harbin Institute of TechnologyHarbin 150001China Department of.Electronic Engineering Chinese University of Hong KongHong Kong 999077China

Spectral compressive imaging has emerged as a powerf.l technique to collect the 3D spectral inf.rmation as 2D *** algorithm f.r restoring the original 3D hyperspectral images(HSIs)f.om compressive measurements is pivotal in the imaging *** approaches painstakingly designed networks to directly map compressive measurements to HSIs,resulting in the lack of.interpretability without exploiting the imaging *** some recent works have introduced the deep unf.lding f.amework f.r explainable reconstruction,the perf.rmance of.these methods is still limited by the weak inf.rmation transmission between iterative *** this paper,we propose a Memory-Augmented deep Unf.lding Network,termed MAUN,f.r explainable and accurate HSI ***,MAUN implements a novel CNN scheme to f.cilitate a better extrapolation step of.the f.st iterative shrinkage-thresholding algorithm,introducing an extra momentum incorporation step f.r each iteration to alleviate the inf.rmation ***,to exploit the high correlation of.intermediate images f.om neighboring iterations,we customize a cross-stage transf.rmer(CSf.rmer)as the deep denoiser to simultaneously capture self.similarity f.om both in-stage and cross-stage f.atures,which is the f.rst attempt to model the long-distance dependencies between iteration *** experiments demonstrate that the proposed MAUN is superior to other state-of.the-art methods both visually and *** code is publicly available at https://***/HuQ1an/MAUN.

关键词： Deep f.lding iteration

Gradient microstructure and superior strength-ductility synergy of.AZ61 magnesium alloy bars processed by radial f.rging with dif.erent def.rmation temperatures

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Journal of.Materials Science & Technology 2024年第3期170卷 65-77页

作者： Jingf.ng Zou Lif.ng Ma Yanchun Zhu Ling Qin yuan yuan School of.Mechanical Engineering Taiyuan University of Science and TechnologyTaiyuan 030024China Heavy Machinery Engineering Research Center of.the Ministry Education Taiyuan University of Science and TechnologyTaiyuan 030024China Department of.Engineering University of HullCottingham RdHull HU67RXUK National Engineering Research Center f.r Magnesium Alloys Chongqing UniversityChongqing 400044China

Gradient microstructure modif.cation is a cost-ef.icient strategy f.r high strength without compromising ductility,which is urgently needed in the f.ndamental science of.engineering *** this study,heterogeneous structures of.AZ61 alloy bars with anisotropic gradients(with dif.erent grain size distributions f.om the surf.ce to the center)were observed to exhibit strong strength-ductility synergies under dif.erent def.rmation tem *** results reveal that the grain ref.nement process under mediumlow temperature def.rmation conditions(≤350℃)consists of.f.ur transition stages along the radial direction,i.e.,twin activations and def.rmation band f.rmations,dislocation cells and pile-ups,ultraf.ne sub-grains,and randomly orientated quasi-micron *** def.rmation temperatures have a great inf.uence on twin activations and def.rmation band f.rmations,and the high temperature can easily provoke the initiation of.non-basal *** def.rmation bands were determined as a primary nucleation site due to their highly unstable dislocation hindrance *** in combination with the Radial f.rging(Rf.def.rmation process,the dif.erences of.dynamic precipitates can be attributed to microstructural dif.erence and solubility limit of.Al at dif.erent tem *** summarizing the tensile test results,the sample f.rged at 350℃exhibited the best strength-ductility synergy,exhibiting the highest elongation(EL)of.23.2%with a 251 MPa yield strength(YS)and 394 MPa ultimate tensile strength(UTS)in center region,and combined with the highest strength value of.256 MPa YS and 420 MPa UTS in the center region,while the EL was slightly degraded to 19.8%.

关键词： Gradient microstructure Radial f.rging Strength-ductility synergy Magnesium alloy Strengthening mechanism