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Journal of Materials science & Technology 2024年第2期169卷 53-67页

作者： Y.B.Zhang s.J.song F.Liu state Key Laboratory of solidification Processing Northwestern Polytechnical UniversityXi’an 710072China Analytical&Testing Center Northwestern Polytechnical UniversityXi’an 710072China

Using dislocation-based constitutive modeling in three-dimension crystal plasticity finite element(3D CPFE)simulations,co-deformation and instability of hetero-phase interface in different material systems were herein studied for polycrystalline metal matrix composites(MMCs).Local stress and strain fields in two types of 3layer MMCs such as fcc/fcc Cu-Ag and fcc/bcc Cu-Nb have been predicted under simple compressive ***,more severe strain-induced interface instability can be observed in the fcc/bcc systems than in the fcc/fcc systems upon refining to metallic nanolayered composites(MNCs).By detailed analysis of stress and strain localization,it has been demonstrated that the interface instability is always accompanied by high-stress concentration,i.e.,thermodynamic characteristics,or high strain prevention i.e.,kinetic characteristics,at the hetero-phase *** then follows that the thermodynamic driving forceG and the kinetic energy barrier Q during dislocation and shear banding can be adopted to classify the deformation modes,following the so-called thermo-kinetic *** by inserting a high density of high-energy interfaces into the Cu-Nb composites,such thermo-kinetic integration at the hetero-phase interface allows a successful establishment of MMCs with the high△G-high Q deformation mode,which ensures high hardening and uniform strain distri-bution,thus efficiently suppressing the shear band,stabilizing the hetero-phase interface,and obtaining an exceptional combination in strength and *** hetero-phase interface chosen by a couple of thermodynamics and kinetics can be defined as breaking the thermo-kinetic correlation and has been proposed for artificially designing MNCs.

关键词： Thermodynamics and kinetics Physics-based constitutive modeling Hetero-phase interface Crystal plasticity finite element

Flat Band and η-Pairing states in a One-Dimensional MoiréHubbard Model

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Chinese Physics Letters 2024年第4期41卷 69-76页

作者：王冉宋智 College of Physics and Materials science Tianjin Normal UniversityTianjin 300387China school of Physics Nankai UniversityTianjin 300071China

A Moirésystem is formed when two periodic structures have a slightly mismatched period,resulting in unusual strongly correlated states in the presence of particle-particle *** periodic structures can arise from the intrinsic crystalline order and periodic external *** investigate a one-dimensional Hubbard model with periodic on-site potential of period n_(0),which is commensurate to the lattice *** large n_(0),the exact solution demonstrates that there is a midgap flat band with zero energy in the absence of Hubbard *** Moiréunit cell contributes two zero energy levels to the flat *** the presence of Hubbard interaction,the midgap physics is demonstrated to be well described by a uniform Hubbard chain in which the effective hopping and on-site interaction strength can be controlled by the amplitude and period of the external *** simulations are performed to demonstrate the correlated behaviors in the finite-sized Moiré Hubbard system,including the existence of an η-pairing state and bound pair *** finding provides a method to enhance the correlated effect by a spatially periodic external field.

关键词： oscillation interaction field

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The Persistence and Zonal scale of Atmospheric Dipolar Modes

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Advances in Atmospheric sciences 2024年第3期41卷 478-492页

作者： Jie song state Key Laboratory of Numerical Modeling for Atmospheric sciences and Geophysical Fluid Dynamics(LAsG) Institute of Atmospheric Physics(IAP)Chinese Academy of SciencesBeijing 100029China

This study investigates the relationship between the persistence and the zonal scale of atmospheric dipolar modes(DMs). results from the daily data of ErA5 and the long-term output of an idealized atmospheric model show that the atmospheric DMs with a broader(narrower) zonal scale dipolar structure possess a longer(shorter) persistence. A detailed vorticity budget analysis indicates that the persistence of a hemispheric-scale DM(1/1 DM) and a regional or sectoral DM(1/8 DM) in the model both largely rely on the persistence of the nonlinear eddy forcing. Linear terms can indirectly reduce the persistence of the anomalous nonlinear eddy forcing in a 1/8 DM by modifying the baroclinicity via the arousal of anomalous vertical motions. Therefore, the atmospheric DMs with a broader(narrower) zonal scale possess a longer(shorter) persistence because the effects of the linear terms are less(more) pronounced when the atmospheric DMs have better(worse) zonal symmetry. Further analyses show that the positive eddy feedback effect is weak or even absent in a 1/8DM and the high-frequency eddy forcing acts more like a concomitant phenomenon rather than a leading driving factor for a 1/8 DM. Thus, the hemispheric-scale DM and the regional or sectoral DMs are different, not only in their persistence but also in their dynamics.

关键词： NAM NAO eddy feedback persistence linear term

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Identification of Linear systems Using Binary sensors with random Thresholds

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Journal of systems science & Complexity 2024年第3期37卷 907-923页

作者： HUANG Zhiyong song Qijiang school of Mathematics Renmin University of ChinaBeijing 100872China school of Mathematics Sino-French InstituteRenmin University of ChinaBeijing 100872China

In this paper,the problem of identifying autoregressive-moving-average systems under random threshold binary-valued output measurements is *** the help of stochastic approximation algorithms with expanding truncations,the authors give the recursive estimates for the parameters of both the linear system and the binary *** reasonable conditions,all constructed estimates are proved to be convergent to the true values with probability one,and the convergence rates are also established.A simulation example is provided to justify the theoretical results.

关键词： α-mixing binary sensor quantized system stochastic approximation stochastic thresh-old strongly consistent system identification

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The learning curve for transurethral enucleation with bipolar energy for benign prostate hyperplasia:a single-surgeon experience of 494 patients

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Asian Journal of Andrology 2024年第3期26卷 288-294页

作者： Byeongdo song sang Hun song seong Jin Jeong Department of Urology Seoul National University Bundang HospitalSeongnam 13620Korea Department of Urology Seoul National University College of MedicineSeoul 03080Korea

This study was performed to investigate the learning curve of transurethral enucleation with bipolar energy(TUEB)for benignprostatic *** study involved 494 consecutive patients who underwent TUEB for benign prostatic hyperplasia fromAugust 2018 to March 2022 by one surgeon(sJJ,seoul National University Bundang Hospital,seongnam,Korea).The patientswere followed up at 1 week,1 month,3 months,and 6 months *** evaluate the learning curve of TUEB,perioperativeparameters including the enucleation ratio(enucleated tissue weight/transitional zone volume),TUEB efficiency(enucleatedtissue weight/operation time),and enucleation efficiency(enucleated tissue weight/enucleation time)were *** and postoperative complications were also assessed,including the International Prostate symptom score(IPss),IPssquality-of-life(QoL)score,and uroflowmetry *** patients’median age was 72(interquartile range[IQr]:66–78)years,and the estimated prostate volume and transitional zone volume were 63.0(IQr:46.0–90.6)ml and 37.1(IQr:24.0–60.0)ml,*** enucleation ratio,TUEB efficiency,and enucleation efficiency were 0.60(IQr:0.46–0.54)g ml−1,0.33(IQr:0.22–0.46)g min−1,and 0.50(IQr:0.35–0.72)g min−1,respectively,plateauing after 70 *** functional outcomes,including total IPss,IPss QoL score,and uroflowmetry outcomes,significantly improved at 6 months after TUEB(all Psignificant differences over the learning ***-five(13.2%)patients developed complications after TUEB,21.5%of whom experienced major complications(Clavien–Dindo grade≥3).The rate of major complications declined as the number ofTUEB cases increased(P=0.013).Our results suggest that the efficiency of TUEB stabilized within 70 procedures.

关键词： benign prostate hyperplasia learning curve perioperative efficiency prostate transurethral enucleation with bipolar energy

self-healing Ga-based liquid metal/alloy anodes for rechargeable batteries

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Nano research 2024年第3期17卷 1366-1383页

作者： Meijia song Zhonghua Zhang school of Energy and Power Jiangsu University of Science and TechnologyZhenjiang 212000China Key Laboratory for Liquid-solid structural Evolution and Processing of Materials(Ministry of Education) School of Materials Science and EngineeringShandong UniversityJingshi Road 17923Jinan 250061China

With the rapid development of electronics,electric vehicles,and grid energy storage stations,higher requirements have been put forward for advanced secondary *** metal/alloy electrodes have been considered as a promising development direction to achieve excellent electrochemical performance in metal-ion batteries,due to their specific advantages including the excellent electrode kinetics and self-healing ability against microstructural electrode *** conventional liquid batteries,high temperatures are needed to keep electrode liquid and ensure the high conductivity of molten salt electrolytes,which also brings the corrosion and safety ***-based metal/alloys,which can be operated at or near room temperature,are potential candidates to circumvent the above *** this review,the properties and advantages of Ga-based metal/alloys are ***,Ga-based liquid metal/alloys as anodes in various metal-ion batteries are reviewed in terms of their self-healing ability,battery configurations,working mechanisms,and so ***,some views on the future development of Ga-based electrodes in batteries are provided.

关键词： metal-ion batteries Ga-based liquid metal/alloy anodes self-healing capability room temperature

FEA-based Geometrical Modification of switched reluctance Motor for radial Force reduction

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Chinese Journal of Electrical Engineering 2024年第1期10卷 124-135页

作者： rani s Jayapragash r school of Electrical Engineering Vellore Institute of TechnologyChennai 600127India

switched reluctance motors(srMs)are becoming increasingly popular in the automotive sector owing to their robust ***,srMs are preferred particularly for EV applications owing to their fault tolerance,magnet-free structure,and high power/torque *** main concerns of srM compared to other machines include torque ripple and *** primary cause of vibration is the radial force created by the srM.A geometry-based modification of the srM to reduce the radial force without significantly changing the average torque produced is *** primary goal is to design a 4-phase,8/6 srM with a lower radial *** possible geometrical alterations are proposed:one with square windows and the other with circular holes on the rotor *** windows are sized and positioned to avoid flux *** criteria are developed for the optimal window size and *** element analysis(FEA)modelling of the srM is used to validate its *** FEA results are compared with the performance parameters obtained using the analytical *** the multiphysics design tool ANsYs to obtain the natural frequencies and associated deformations through modal *** to the conventional geometry,the radial force is significantly reduced by providing windows.

关键词： 8/6 srM radial force modal analysis FEA analysis natural frequencies srM with windows

Optimizing multi-parameter distributed fiber sensors:a hybrid rayleigh-Brillouin-raman system approach

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Light(science & Applications) 2024年第3期13卷 393-395页

作者： Kwang Yong song Dept.of Physics Chung-Ang University84 Heukseok-roDongjak-guSeoul 06974Korea

An optimized single-end hybrid rayleigh,Brillouin,and raman distributed fiber sensing system has been developed for simultaneous measurement of multiple *** system integrates 3-bit pulse coding for the raman signal and the Brillouin amplification of the rayleigh-backscattered signal,discriminating strain,temperature,and vibration using a single sensing fiber.

关键词： fiber rayleigh signal

Berry-Esseen bounds for self-normalized sums of locally dependent random variables

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science China Mathematics 2024年第11期67卷 2629-2652页

作者： Zhuo-song Zhang Department of statistics and Data science Southern University of Science and Technology

The Berry-Esseen bound provides an upper bound on the Kolmogorov distance between a random variable and the normal *** this paper,we establish Berry-Esseen bounds with optimal rates for self-normalized sums of locally dependent random variables,assuming only a second-moment *** proof leverages stein's method and introduces a novel randomized concentration inequality,which may also be of independent interest for other *** main results have applied to self-normalized sums of m-dependent random variables and graph dependency models.

关键词： Berry-Esseen bounds self-normalized sums localdependence $m$-dependence graph dependency

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