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Communications in Theoretical Physics 2024年第4期76卷 93-112页

作者： Ruo-Qing ding Xiao-Ming Xu H j Weber department of Physics Shanghai UniversityBaoshanShanghai 200444China department of Physics University of VirginiaCharlottesvilleVA 22904United States of America

We study the dissociation of ψ(3770), ψ(4040), ψ(4160), and ψ(4415) mesons in collision with nucleons, which takes place in high-energy proton-nucleus collisions. The quark interchange between a nucleon and a ■ meson leads to the dissociation of the ■ meson. We consider the reactions:■, and■, where R stands for ψ(3770), ψ(4040), ψ(4160), or ψ(4415). A reaction of a neutron and a ■ meson corresponds to a reaction of a proton and the ■ meson by replacing the up quark with the down quark and vice versa. Transition-amplitude formulas are derived from the S-matrix *** cross sections are calculated with the transition amplitudes for scattering in the prior form and in the post form. The cross sections relate to nodes in the radial wave functions of ψ(3770), ψ(4040), ψ(4160), and ψ(4415) mesons.

关键词： inelastic nucleon-charmonium scattering quark interchange relativistic constituent quark potential model

A REdUCEd ORdER SCHWARZ METHOd FOR NONLINEAR MULTISCALE ELLIPTIC EQUATIONS BASEd ON TWO-LAYER NEURAL NETWORKS

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journal of Computational Mathematics 2024年第2期42卷 570-596页

作者： Shi Chen Zhiyan ding Qin Li Stephen j.Wright Mathematics department University of Wisconsin-MadisonMadisonWI 53706USA department of Mathematics University of California-BerkeleyBerkeley CA 94720USA Mathematics department and discovery Institute University of Wisconsin-Madison MadisonWI 53706USA Computer Sciences department University of WisconsinMadisonWI 53706USA

Neural networks are powerful tools for approximating high dimensional data that have been used in many contexts,including solution of partial differential equations(PdEs).We describe a solver for multiscale fully nonlinear elliptic equations that makes use of domain decomposition,an accelerated Schwarz framework,and two-layer neural networks to approximate the boundary-to-boundarymap for the subdomains,which is the key step in the Schwarz ***,the boundary-to-boundary map requires solution of boundary-value elliptic problems on each *** leveraging the compressibility of multiscale problems,our approach trains the neural network offline to serve as a surrogate for the usual implementation of the boundary-to-boundary *** method is applied to a multiscale semilinear elliptic equation and a multiscale p-Laplace *** both cases we demonstrate significant improvement in efficiency as well as good accuracy and generalization performance.

关键词： Nonlinear homogenization Multiscale elliptic problem Neural networks do-main decomposition

deep structure of the Southeast Asian curved subduction system and its dynamic process

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journal of Oceanology and Limnology 2024年第3期42卷 701-704页

作者： Weiwei ding Key Laboratory of Submarine Geoscience&Second Institute of Oceanography Ministry of Natural ResourcesHangzhou 310012China School of Oceanography Shanghai Jiao Tong UniversityShanghai 200030China

The deep structure,material circulation,and dynamic processes in the Southeast Asia have long been an elusive scientific puzzle due to the lack of systematic scientific observations and recognized theoretical *** on the deep seismic tomography using long-period natural earthquake data,in this study,the deep structure and material circulation of the curved subduction system in Southeast Asia was studied,and the dynamic processes since 100 million years ago was *** is pointed out that challenges still exist in the precise reconstruction of deep mantle structures of the study area,the influence of multi-stage subduction on deep material exchange and shallow magma activity,as well as the spatiotemporal evolution and coupling mechanism of multi-plate *** work should focus on high-resolution land-sea joint 3-d seismic tomography imaging of the curved subduction system in the Southeast Asia,combined with geochemical analysis and geodynamic modelling works.

关键词： curved subduction system deep structure material recycling dynamic process Southeast Asia

Physical activity volume,frequency,and intensity:Associations with hypertension and obesity over 21 years in Australian women

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journal of Sport and Health Science 2024年第5期13卷 631-641页

作者： Gregore I.Mielke ding ding Shelley E.Keating Bruno P.Nunes Ruth Brady Wendy j.Brown School of Public Health The University of QueenslandBrisbaneQLD 4006Australia Sydney School of Public Health Faculty of Medicine and HealthThe University of SydneySydneyNSW 2006Australia The Charles Perkins Centre The University of SydneySydneyNSW 2006Australia School of Human Movement and Nutrition Sciences The University of QueenslandBrisbaneQLD 4072Australia School of Nursing Federal University of PelotasPelotasRio Grande do Sul 96010-610Brazil Faculty of Health Sciences and Medicine Bond UniversityGold CoastQLD 4226Australia

Background:Optimal patterns of accrual of recommended levels of physical activity(PA)for prevention of hypertension and obesity are not *** overall aim of this study was to investigate whether different patterns of accumulation of PA are differentially associated with hypertension and obesity in Australian women over 21 ***,we investigated whether,for the same weekly volume of PA,the number of sessions(frequency)and vigorousness of PA(intensity)were associated with a reduction in the occurrence of hypertension and obesity in ***:data from the 1973-1978 and 1946-1951 cohorts of the Australian Longitudinal Study on Women's Health were analyzed(n=20,588;12%-16%with a Bachelor's or higher degree).Self-reported PA,hypertension,height,and weight were collected using mail surveys every 3 years from 1998/2000 to 2019/*** Estimating Equation models with a 3-year lag model were used to investigate the association of PA volume(metabolic equivalent min/week)(none;33-499;500-999;≥1000,weekly frequency(none;1-2 times;3-4times;5-7 times;≥8 times),and the proportion of vigorous PA to total volume of PA(none;0%;1%-33%;34%-66%;67%-100%)with odds of hypertension and obesity from 2000 to ***:The cumulative incidence of hypertension was 6%in the 1973-1978 and 23%in the 1946-1951 cohort;27%of women in the 1973-1978;and 15%in the 1946-1951 cohort developed obesity over the ***,a higher volume of PA was associated with reduced odds of hypertension and *** the volume of PA was considered,the odds of hypertension did not vary according to the frequency or intensity of ***,increased proportion of vigorous PA to the total volume of PA was associated with a small additional reduction in the risk of obe ***:PA volume appears to be more important than the pattern of accumulation for the prevention of hypertension and *** more sessions,particularly of vigorous-intensity PA,may provide extr

关键词： Physical activity Frequency Intensity Incidences Epidemiology Women

Theoretical and experimental study of a bi-stable piezoelectric energy harvester under hybrid galloping and band-limited random excitations

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Applied Mathematics and Mechanics(English Edition) 2024年第3期45卷 461-478页

作者： Haitao LI Tianyu ZHENG Weiyang QIN Ruilan TIAN Hu ding j.C.jI Liqun CHEN department of Engineering Mechanics North University of ChinaTaiyuan 030051China department of Engineering Mechanics Northwestern Polytechnical UniversityXi'an 710072China department of Engineering Mechanics Shijiazhuang Tiedao UniversityShijiazhuang 050043China Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Frontier Science Center of MechnoinformaticsShanghai Institute of Applied Mathematics and MechanicsSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai 200072China School of Mechanical and Mechatronic Engineering University of Technology SydneyNew South Wales 2007Australia

In the practical environment,it is very common for the simultaneous occurrence of base excitation and *** the combined energy of vibration and wind with a single energy harvesting structure is *** this purpose,the effects of the wind speed and random excitation level are investigated with the stochastic averaging method(SAM)based on the energy *** results of the analytical prediction are verified with the Monte-Carlo method(MCM).The numerical simulation shows that the introduction of wind can reduce the critical excitation level for triggering an inter-well jump and make a bi-stable energy harvester(BEH)realize the performance enhancement for a weak base ***,as the strength of the wind increases to a particular level,the influence of the random base excitation on the dynamic responses is weakened,and the system exhibits a periodic galloping response.A comparison between a BEH and a linear energy harvester(LEH)indicates that the BEH demonstrates inferior performance for high-speed *** experiments are conducted to investigate the validity of the theoretical prediction and numerical *** experimental findings also show that strong random excitation is favorable for the BEH in the range of low wind ***,as the speed of the incoming wind is up to a particular level,the disadvantage of the BEH becomes clear and evident.

关键词： bi-stability inter-well response galloping band-limited random

Large magnetostriction of Nd_(0.2)Tb_(0.3)dy_(0.5)Fe_(1.93)/epoxy composites in a wide temperature range

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journal of Rare Earths 2024年第4期42卷 705-709页

作者： Hehe ding Yangguang Shi Shaolong Tang MIIT Key Laboratory of Aerospace Information Materials and Physics Department of Applied PhysicsNanjing University of Aeronautics and AstronauticsNanjing210016China National Laboratory of Solid State Microstructures Nanjing UniversityNanjing210093China

We report the magnetostrictive performance of the Nd_(0.2)Tb_(0.3)dy_(0.5)Fe_(1.93)/epoxy *** of M?ssbauer spectra and the XRd results indicate that the easy magnetic direction of the Nd_(0.2)Tb_(0.3)dy_(0.5)Fe_(1.93)compound is alongdirection with spontaneous magnetostrictionλ111 of1900 ***-oriented Nd_(0.2)Tb_(0.3)dy_(0.5)Fe_(1.93)/epoxy composites with particle volume fractions of20 vol%-55 vol%were *** measurements demonstrate that the composite is highly *** raw material cost of Nd_(0.2)Tb_(0.3)dy_(0.5)Fe_(1.93)is about 85%of that of the Terfenol-d(Tb_(0.3)dy_(0.7)Fe_(2))***_(0.2)Tb_(0.3)dy_(0.5)Fe_(1.93)/epoxy composites possess comparable magnetostriction with those composites made of Tb_(0.3)dy_(0.7)Fe_(2)*** room temperature,the magnetostrictionλ_Ⅱof the Nd_(0.2)Tb_(0.3)dy_(0.5)Fe_(1.93)/epoxy composite reaches 420 ppm at a low field of 80 kA/m and about1000 ppm at 239 kA/*** addition,the composite exhibits a large saturation magnetostrictionλ_Ⅱover1200 ppm from 300 to 100 K,suggesting its potential applications as a low-cost magnetostrictive material in a wide temperature ***,the current study offers an opportunity to widen the operating temperature range of the magnetostrictive composite.

关键词： Magnetostrictive composite Nd_(0.2)Tb_(0.3)dy_(0.5)Fe_(1.93) Wide temperaturerange Laves phase Rare earths

Unveiling the time-temperature dependence of metastability of supercooled liquid using nano-calorimetry

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Science China(Physics,Mechanics & Astronomy) 2024年第3期67卷 119-127页

作者： Yijun ding Lijian Song Zheng Wang Ruiqi Yu junqiang Wang Lina Hu Yuanzheng Yue Edgar d.Zanotto Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials(Ministry of Education) Shandong University Jinan 250061China Ningbo Institute of Materials Technology and Engineering Chinese Academy of SciencesNingbo 315201China Key Laboratory of Experimental Teratology Shandong University jinan 250061 China department of Chemistry and Bioscience Aalborg UniversityAalborg 9220Denmark department of Materials Engineering Federal University of Sao CarlosSao Carlos SP 13.565-905Brazil

There is a lack of understanding of both the conversion of an unstable glass into a metastable supercooled liquid(MSL) upon heating and the metastability of MSLs. In this study, we investigated the time-and temperature-dependent metastability of an MSL using an advanced nano-calorimetric technique. The chosen Au-based metallic glass(Au MG) allowed adequate probing of its MSL in a temperature range between 10 and 70 K above the standard glass transition temperature. We found that the survival time of the MSL state is a quadratic function of temperature. Beyond this duration threshold, the sample undergoes fast crystallization even if it is below the crystallization temperature that is measured using differential scanning *** transmission electron microscopy, we observed the formation of clusters with a partially ordered lattice structure during relaxation in the Au MG sample fabricated using a nano-calorimeter. The atomic ordering within the clusters was enhanced by increasing time and temperature in the MSL region. Once the as-produced glass entered the MSL stage upon heating followed by a quenching stage at a given rate, the mechanical properties of the quenched glass remained the same regardless of its holding temperature and duration within the MSL region. This work provides insights into the glass-MSL-crystal transformation and offers guidance for designing standard metallic glasses for property characterizations.

关键词： metallic glass supercooled liquid relaxation nucleation nano calorimetric technology

Analytical model for predicting time-dependent lateral deformation of geosynthetics-reinforced soil walls with modular block facing

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journal of Rock Mechanics and Geotechnical Engineering 2024年第2期16卷 711-725页

作者： Luqiang ding Chengzhi Xiao Feilong Cui School of Civil and Transportation Engineering Hebei University of TechnologyTianjin300401China

To date,few models are available in the literature to consider the creep behavior of geosynthetics when predicting the lateral deformation(d)of geosynthetics-reinforced soil(GRS)retaining *** this study,a general hyperbolic creep model was first introduced to describe the long-term deformation of geosynthetics,which is a function of elapsed time and two empirical parameters a and *** conventional creep tests with three different tensile loads(Pr)were conducted on two uniaxial geogrids to determine their creep behavior,as well as the a-Pr and b-Pr *** test results show that increasing Pr accelerates the development of creep deformation for both ***,a and b respectively show exponential and negatively linear relationships with Pr,which were confirmed by abundant experimental data available in other *** on the above creep model and relationships,an accurate and reliable analytical model was then proposed for predicting the time-dependent d of GRS walls with modular block facing,which was further validated using a relevant numerical investigation from the previous *** evaluation and comparison of the proposed model with six available prediction models were *** a parametric study was carried out to evaluate the effects of wall height,vertical spacing of geogrids,unit weight and internal friction angle of backfills,and factor of safety against pullout on d at the end of construction and 5 years *** findings show that the creep effect not only promotes d but also raises the elevation of the maximum d along the wall ***,the limitations and application prospects of the proposed model were discussed and analyzed.

关键词： Geosynthetics Creep behavior Geosynthetics-reinforced soil(GRS)walls Lateral deformation Analytical model

Heat management technology for solid-state high voltage and high repetitive pulse generators:Towards better effects and reliability

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High Voltage 2024年第1期9卷 2-21页

作者： Yanan Wang Linyuan Ren Zihao Yang Saikang Shen Zichen deng Qi Yuan Weidong ding Zhenjie ding School of Electrical Engineering Xi'an Jiaotong UniversityXi'anChina School of Electronic and Information Engineering Xi'an Jiaotong UniversityXi'anChina

Solid-state high voltage high repetitive pulse generators have a broad prospect in various *** high power and high-frequency operation of the pulse generator suffer from the massive heat dissipation problem,which limits the improvement of the output parameters and even affects the *** article focuses on heat management technology for high voltage high repetitive pulse ***,the typical circuit topology of the high repetitive pulse generators was *** the perspective of different application requirements,the demands of the heat management design were ***,the heat generation characteristics and difficulties of solid-state high voltage high repetitive pulse generators were ***,the different stateof-art cooling techniques were reviewed,and their applicability and limitations for the high voltage high repetitive generators were ***,a flow chart for heat management design was given.

关键词： pulse state high