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Nano-Micro Letters 2025年第2期17卷 376-386页

作者： Wei-Min Qin Zhongliang Li Wen‑Xia Su jia‑Min hu Hanqin Zou Zhixuan Wu Zhiqin Ruan Yue‑Peng Cai Kang Li Qifeng Zheng School of Chemistry South China Normal UniversityGuangzhou 510006People’s Republic of China Key Laboratory of Functional Metal‑Organic Compounds of hunan Province College of Chemistry and Material ScienceHengyang Normal UniversityHengyang 421008People’s Republic of China Guangzhou Key Laboratory of Energy Conversion and Energy Storage Materials Guangzhou 510006People’s Republic of China

Porous organic cages(POCs)with permanent porosity and excellent host–guest property hold great potentials in regulating ion transport behavior,yet their feasibility as solid-state electrolytes has never been testified in a practical ***,we design and fabricate a quasi-solid-state electrolyte(QSSE)based on a POC to enable the stable operation of Li-metal batteries(LMBs).Benefiting from the ordered channels and cavity-induced anion-trapping effect of POC,the resulting POC-based QSSE exhibits a high Li+transference number of 0.67 and a high ionic conductivity of 1.25×10^(−4) S cm^(−1) with a low activation energy of 0.17 *** allow for homogeneous Li deposition and highly reversible Li plating/stripping for over 2000 *** a proof of concept,the LMB assembled with POC-based QSSE demonstrates extremely stable cycling performance with 85%capacity retention after 1000 ***,our work demonstrates the practical applicability of POC as SSEs for LMBs and could be extended to other energy-storage systems,such as Na and K batteries.

关键词： Porous organic cage Cavity-induced anion-trapping Quasi-solid-state electrolyte Homogeneous Li+flux Lithium metal battery

Excitation and detection of coherent sub-terahertz magnons in ferromagnetic and antiferromagnetic heterostructures

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npj Computational Materials 2022年第1期8卷 1606-1614页

作者： Shihao Zhuang jia-Mian hu Department of Materials Science and Engineering University of Wisconsin-MadisonMadisonWI53706USA

Excitation of coherent high-frequency magnons(quanta of spin waves)is critical to the development of high-speed magnonic *** we computationally demonstrate the excitation of coherent sub-terahertz(THz)magnons in ferromagnetic(FM)and antiferromagnetic(AFM)thin films by a photoinduced picosecond acoustic *** calculations are also performed to reveal the magnon excitation *** spin pumping and spin-charge conversion,these magnons can inject sub-THz charge current into an adjacent heavy-metal film which in turn emits electromagnetic(EM)*** a dynamical phase-field model that considers the coupled dynamics of acoustic waves,spin waves,and EM waves,we show that the emitted EM wave retains the spectral information of all the sub-THz magnon modes and has a sufficiently large amplitude for near-field *** predictions indicate that the excitation and detection of sub-THz magnons can be realized in rationally designed FM or AFM thin-film heterostructures via ultrafast optical-pump THz-emission-probe spectroscopy.

关键词： pumping pump coherent

Manufacturing and testing of X-ray imaging components with high precision

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光学精密工程 2005年第5期13卷 620-625页

作者： hu jia sheng WU Xü School of Electronic and Information Engineering Dalian University of Technology Dalian 116024China College of Information Technology Dalian Maritime University Dalian 116026 China

In the latest 20 years, X-ray imaging technology has developed rapidly in order to meet the needs of X-ray photo-etching,spatial exploration technology, high-energy physics, procedure diagnosis of ICF,etc. Since refractive indices of materials in the X-ray region are lower than 1, and X-ray is strongly absorbed by materials, the characteristics of X-ray increase greatly difficulty to obtain X-ray image. Conventional imaging methods are hardly suitable to X-ray range. In general, grazing reflective imaging and coding aperture imaging methods have been adopted more and *** have designed a non-coaxial grazing reflective X-ray microscope which is composed of four spherical mirrors, in order to satisfy the requirement of the diagnosis of inertial confinement fusion (ICF). The four mirrors have the same radius of curvature. The radius of each mirror is 29 000 mm and the aperture is 30 mm×15 mm. Allowable tolerance of the radius is ≤0.2% and one of surface roughness (rms) is ≤0.6 nm. Evidently it is very difficult to fabricate and test such mirrors. In order to obtain eligible mirrors, we choose 18 mirror roughcasts and array them on a round disk according to format. The combined manufacturing method can ensure high accordant quality. The fabricated mirrors are tested by both templet and double round aperture methods. Radius errors of the mirrors is about 53 mm. The surface roughness (rms) of the mirrors is inspected by the relative interferometric equipment (WYKO) and atomic force microscope. Before and after coating the measured surface roughness is averagely 0.52 nm and 0.4 nm, respectively.

关键词： X光线图像质量评价纳米精度

A Symmetric Linearized Alternating Direction Method of Multipliers for a Class of Stochastic Optimization Problems

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Journal of Systems Science and Information 2023年第1期11卷 58-77页

作者： jia hu Qimin hu Networked Supporting Software International S&T Cooperation Base of China Jiangxi Normal UniversityNanchang 330022China

Alternating direction method of multipliers(ADMM)receives much attention in the recent years due to various demands from machine learning and big data related *** 2013,Ouyang et *** the ADMM to the stochastic setting for solving some stochastic optimization problems,inspired by the structural risk minimization *** this paper,we consider a stochastic variant of symmetric ADMM,named symmetric stochastic linearized ADMM(SSL-ADMM).In particular,using the framework of variational inequality,we analyze the convergence properties of ***,we show that,with high probability,SSL-ADMM has O((ln N)·N^(-1/2))constraint violation bound and objective error bound for convex problems,and has O((ln N)^(2)·N^(-1))constraint violation bound and objective error bound for strongly convex problems,where N is the iteration *** ADMM can improve the algorithmic performance compared to classical ADMM,numerical experiments for statistical machine learning show that such an improvement is also present in the stochastic setting.

关键词： alternating direction method of multipliers stochastic approximation expected convergence rate and high probability bound convex optimization machine learning

Field-free spin-orbit torque perpendicular magnetization switching in ultrathin nanostructures

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npj Computational Materials 2020年第1期6卷 1004-1013页

作者： Minyi Dai jia-Mian hu Department of Materials Science and Engineering University of Wisconsin-MadisonMadisonWI 53705USA

Magnetic-field-free current-controlled switching of perpendicular magnetization via spin-orbit torque(SOT)is necessary for developing a fast,long data retention,and high-density SOT magnetoresistive random access memory(MRAM).Here,we use both micromagnetic simulations and atomistic spin dynamics(ASD)simulations to demonstrate an approach to field-free SOT perpendicular magnetization switching without requiring any changes in the architecture of a standard SOT-MRAM *** show that this field-free switching is enabled by a synergistic effect of lateral geometrical confinement,interfacial Dyzaloshinskii–Moriya interaction(DMI),and current-induced *** micromagnetic and atomistic understanding of the nucleation and growth kinetics of the reversed domain are ***,atomically resolved spin dynamics at the early stage of nucleation is revealed using ASD simulations.A machine learning model is trained based on~1000 groups of benchmarked micromagnetic simulation *** machine learning model can be used to rapidly and accurately identify the nanomagnet size,interfacial DMI strength,and the magnitude of current density required for the field-free switching.

关键词： reversed magnetization interfacial

Science Letters:Multi-frequency proportional-resonant (MFPR) current controller for PWM VSC under unbalanced supply conditions

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第10期8卷 1527-1531页

作者： hu jia-bing HE Yi-kang Sehool of Eleetrieal Engineering Zhejiang University Hangzhou 310027 China

This letter presents a multi-frequency proportional-resonant （MFPR） current controller developed for PWM voltage source converter （VSC） under the unbalanced supply voltage conditions. The delta operator is used in place of the shift operator for the implementation of MFPR by using a low-cost fixed-point DSE The experimental results with an alternative control strategy validated the feasibility of the proposed MFPR current controller for the PWM VSC during voltage unbalance.

关键词： PWM VSC Multi-frequency proportional-resonant (MFPR) Voltage unbalance

Antenna Sidelobe Canceller of Kalman Filter

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Wuhan University Journal of Natural Sciences 1999年第2期4卷 82-85页

作者： hu, jia-yuan Wuhan Univ Wuhan China

The adaptive array antenna may be considered as a general sidelobe canceller. Directional interference suppression is based on a recursive state estimation of Kalman filter. For the stationary filter,this leads to an iterative solution of Wiener Hops matrix equation. The performance of sidelobe canceller are studied by computer simulation. The result of simulation shows that the sidelobe canceller may be regarded as a special case of an adaptive array atenna.

关键词： Kalmen filter sidelobe canceller adaptive antenna

The Correlation Between Note Features and Consecutive Interpreting Quality for English Majors

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Contemporary Social Sciences 2023年第2期8卷 68-95页

作者： hu jia College of Foreign Languages Taiyuan University of TechnologyTaiyuanShanxi030600China

Note-taking skill is a necessary component in interpreter training programs,and previous research has yielded findings such as note-taking training methods or features of interpreter trainees’***,little research has been done to investigate the changes in note features and correlations between note features and interpreting quality concerning Chinese students’C-E(Chinese-English)and E-C(EnglishChinese)*** the framework of Daniel Gile’s Effort Model and Interpretive Theory of Translation,this paper examined how 45 English Majors’notes develop within one semester(seventeen weeks)and the relationship between note features(quantity,form,and language choice of notes)and consecutive interpreting *** participants of this study were all beginner interpreting trainees,and the note-taking training was introduced in Week *** study employed note manuscripts,interpreting tests,and semi-structured interviews to track the features and changes in students’*** analyses and T-tests showed that(a)after the note-taking training,the number of notes increased from Week 8 to Week 17,and it was positively correlated with interpreting quality(fidelity and delivery)for both C-E and E-C interpreting;(b)as for forms of notes,participants primarily employ single Chinese words and the percentages of abbreviations and symbols rose prominently from Week 8 to Week 17 for C-E ***,correlation analyses show that interpreting quality improves with fewer single Chinese words and more abbreviations and *** E-C interpreting,notes were mainly in English,especially single English words and *** percentages of single Chinese words and abbreviations ascended whereas those of single English words and symbols ***,results show that the more abbreviations and symbols,the better target-text fidelity,and fewer abbreviations,the better the targettext delivery;(c)concerning language choice,notes were mainly in sou

关键词： note features interpreting quality quantity form language

Dynamic modelling and robust current control of wind-turbine driven DFIG during external AC voltage dip

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第10期7卷 1757-1764页

作者： hu jia-bing HE Yi-kang Department of Electrical Engineering Zhejiang University Hangzhou 310027 China

Doubly-Fed Induction Generator （DFIG）, with vector control applied, is widely used in Variable-Speed Constant- Frequency （VSCF） wind energy generation system and shows good performance in maximum wind energy capture. But in two traditional vector control schemes, the equivalent stator magnetizing current is considered invariant in order to simplify the rotor current inner-loop controller. The two schemes can perform very well when the grid is in normal condition. However, when grid disturbance such as grid voltage dip or swell fault occurs, the control performance worsens, the rotor over current occurs and the Fault Ride-Through （FRT） capability of the DFIG wind energy generation system gets seriously deteriorated. An accurate DFIG model was used to deeply investigate the deficiency of the traditional vector control. The improved control schemes of two typical traditional vector control schemes used in DFIG were proposed, and simulation study of the proposed and traditional control schemes, with robust rotor current control using Internal Model Control （IMC） method, was carded out. The validity of the proposed modified schemes to control the rotor current and to improve the FRT capability of the DFIG wind energy generation system was proved by the comparison study.

关键词： Wind energy generation Variable-Speed Constant-Frequency (VSCF) Doubly-Fed Induction Generator (DFIG) Fault Ride-Through (FRT) Internal Model Control (IMC)

On summer stratification and tidal mixing in the Taiwan Strait

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Frontiers of Earth Science 2013年第2期7卷 141-150页

作者： jia Zhu jianyu hu Zhiyu LIU State Key Laboratory of Marine Environmental Science College of Ocean & Earth Sciences Xiamen University Xiamen 361005 China

On continental shelves, a front that separates the sea into well-mixed and stratified zones is usually formed in warm seasons due to spatial variations of tidal mixing. In this paper, using eight years of in situ hydrographic observations, satellite images of sea surface temperature （SST） and chlorophyll-a （Chl-a） concentration, and results of a tidal model, we investigate summer stratification in the Taiwan Strait and its dependence on tidal mixing, upwelling, and river diluted water plumes. In most regions of the strait the dominant role of tidal mixing in determining the thermohaline structure is confirmed by the correlation between the two; there are some regions, however, where thermohaline structure varies in different ways owing to significant influences ofupwelling and river diluted water plumes. The well-mixed regions are mainly distributed on the Taiwan Bank and in the offshore regions off the Dongshan Island, Nanao Island, and Pingtan Island, while the northern and central Taiwan Strait and the region south of the Taiwan Bank are stratified. The critical Simpson-hunter parameter for the region is estimated to be 1.78.

关键词： Taiwan Strait stratification tidal mixing coastal upwelling river plume