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Chinese Physics Letters 2021年第4期38卷 28-33页

作者： jun xu The Interdisciplinary Research Center Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201210China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China

The remaining uncertainties in relation to isovector nuclear interactions call for reliable experimental measurements of isovector probes in finite *** on the Bayesian analysis,although neutron-skin thickness data or isovector giant dipole resonance data in ^(208)Pb can constrain only one isovector interaction parameter,correlations among other parameters can also be *** combined data for both the neutron-skin thickness and the isovector giant dipole resonance helps to significantly constrain all isovector interaction parameters;as such,it serves as a useful methodology for future research.

关键词： dipole interaction finite

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自然语言处理研究综述

新疆师范大学学报（哲学社会科学版） 2025年第2期46卷 89-111,F0002页

作者：赵铁军许木璠陈安东哈尔滨工业大学计算学部黑龙江哈尔滨150001

近年来,自然语言处理因在分析与建模人类语言任务领域取得诸多成果而备受关注。当前,大规模预训练语言模型展现出强大的对话问答和文本生成能力,带来自然语言处理研究的新一轮热潮。自然语言处理在机器翻译、文本摘要、信息抽取等领域... 详细信息

近年来,自然语言处理因在分析与建模人类语言任务领域取得诸多成果而备受关注。当前,大规模预训练语言模型展现出强大的对话问答和文本生成能力,带来自然语言处理研究的新一轮热潮。自然语言处理在机器翻译、文本摘要、信息抽取等领域应用广泛。文本首先讨论自然语言处理针对语言学四个不同层次文本信息的分析手段,对自然语言处理的基本任务组成进行概述;其次,讨论自然语言处理在具体下游任务中的应用现状,包括自然语言处理在具体任务中的应用历史、当前的研究趋势以及面临的挑战;最后,在大规模预训练语言模型研究对数据集提出更高要求的背景下,对自然语言处理领域已有的数据集及评测基准集等进行讨论。

关键词：自然语言处理句法分析语义分析机器翻译问答系统信息抽取

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Data-driven short circuit resistance estimation in battery safety issues

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Journal of Energy Chemistry 2023年第4期79卷 37-44页

作者： Yikai Jia jun xu Department of Mechanical Engineering and Engineering Science The University of North Carolina at CharlotteCharlotteNC 28223USA Vehicle Energy&Safety Laboratory(VESL) North Carolina Battery ComplexityAutonomous Vehicle and Electrification(BATT CAVE)Research CenterThe University of North Carolina at CharlotteCharlotteNC 28223USA School of Data Science The University of North Carolina at CharlotteCharlotteNC 28223USA

Developing precise and fast methods for short circuit detection is crucial for preventing or mitigating the risk of safety issues of lithium-ion batteries(LIBs).In this paper,we developed a Convolutional Neural Networks(CNN)based model that can quickly and precisely predict the short circuit resistance of LIB cells during various working *** tests of cells with an external short circuit(ESC)are produced to obtain the database and generate the training/testing *** samples are sequences of voltage,current,charging capacity,charging energy,total charging capacity,total charging energy with a length of 120 s and frequency of 1 Hz,and their corresponding short circuit resistances.A big database with~6×10^(5)samples are generated,covering various short circuit resistances(47~470Ω),current loading modes(Constant current-constant voltage(CC-CV)and drive cycle),and electrochemical states(cycle numbers from 1 to 300).Results show that the average relative absolute error of five random sample splits is 6.75%±2.8%.Further parametric analysis indicates the accuracy estimation benefits from the appropriate model setups:the optimized input sequence length(~120 s),feature selection(at least one total capacity-related variable),and rational model design,using multiple layers with different kernel *** work highlights the capabilities of machine learning algorithms and data-driven methodologies in real-time safety risk prediction for batteries.

关键词： Lithium-ion battery Safety risk Internal short circuit Short circuit resistance Convolutional neural networks

Steel scrap melting model for a dephosphorisation basic oxygen furnace

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Journal of Iron and Steel Research International 2020年第8期27卷 972-980页

作者： Shuai Deng An-jun xu School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China

Dephosphorisation basic oxygen furnaces (deP-BOFs) greatly differ from conventional BOFs in the melting process, especially its many limits on adding scrap. A mathematical model of the steel scrap melting process was established in MATLAB to investigate the mechanism of scrap melting in deP-BOF in terms of coupling effects of the carbon content of the molten steel, temperature, scrap preheating and converter blowing time on the melting rate and size of the steel scraps. The scrap melting rate was influenced by both the heat and mass transfer during the melting process: at 1350℃, when the carbon content was increased from 4.5 to 5.0 mass%, the scrap melting rate increased by 43%;for the carbon content of 4.5 mass%, when the temperature was increased from 1350 to 1400℃, the scrap melting rate increased by 60%. The carbonisation was found to be the restrictive step of the scrap melting process in deP-BOFs with respect to conventional ones. The scrap heating from room temperature to 800℃ reduced the crusting thickness on the scrap surface but there was no obvious influence on the melting rate. The scrap melting size in the deP-BOF was rather limited by its low melting rate and short melting time.

关键词： Scrap Melting Dephosphorisation basic oxygen furnace Mathematical model Heat transfer Mass transfer

Bayesian inference of neutron-skin thickness and neutron-star observables based on effective nuclear interactions

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Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 97-105页

作者： Jia Zhou jun xu Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China School of Physics Science and Engineering Tongji UniversityShanghai 200092China

We have obtained the constraints on the density dependence of the symmetry energy from neutron-skin thickness data by parityviolating electron scatterings and neutron-star observables using a Bayesian approach,based on the standard Skyrme-HartreeFock(SHF)model and its extension as well as the relativistic mean-field(RMF)*** the neutron-skin thickness data(neutron-star observables)mostly constrain the symmetry energy at subsaturation(suprasaturation)densities,they may more or less constrain the behavior of the symmetry energy at suprasaturation(subsaturation)densities,depending on the energy-density functional *** showing the final posterior density dependence of the symmetry energy,we also compare the slope parameters of the symmetry energy at 0.10 fm-3as well as the values of the symmetry energy at twice saturation density from three effective nuclear *** present work serves as a comparison study based on relativistic and non-relativistic energy-density functionals,for constraining the nuclear symmetry energy from low to high densities using a Bayesian approach.

关键词： symmetry energy neutron skin neutron star

A novel weighting scheme for random k-SAT

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Science China(Information Sciences) 2016年第9期59卷 5-10页

作者： jun LIU Ke xu State Key Laboratory of Software Development Environment Beihang University

Consider a random k-conjunctive normal form F;（n, rn） with n variables and rn clauses. We prove that if the probability that the formula Fk（n, rn） is satisfiable tends to 0 as n →∞, then r≥2.83, 8.09, 18.91,40.... 详细信息

关键词： computational complexity satisfiability phase transition second moment method weighting scheme

Damage evolution and crack propagation in rocks with dual elliptic flaws in compression

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Acta Mechanica Solida Sinica 2017年第6期30卷 573-582页

作者： jun xu Zhaoxia Li Department of Engineering Mechanics Southeast University Nanjing 210096 China Jiangsu Key Laboratory of Engineering Mechanics Southeast University Nanjing 210096 China

To give an insight into the understanding of damage evolution and crack propagation in rocks,a series of uniaxial and biaxial compression numerical tests are carried *** investigations show that damage evolution occurs firstly in the weak rock,the area around the flaw and the area between the flaw and the neighboring rock *** mostly generate as tensile cracks under uniaxial compression and shear cracks under biaxial *** patterns are classified and *** relationship between the accumulated lateral displacement and the short radius（b）is fitted,and the equation of crack path is also established.

关键词： Damage evolution Crack propagation Elliptic flaw

Shear viscosity of nuclear matter

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Nuclear Science and Techniques 2013年第5期24卷 71-75页

作者： xu jun Shanghai Institute of Applied Physics Chinese Academy of SciencesJiading Campus Department of Physics and Astronomy Texas A & M University-CommerceCommerce

This paper reports my recent study[1]on the shear viscosity of neutron-rich nuclear matter from a relaxation time *** isospin- and momentum-dependent interaction is used in the *** of density,temperature,and isospin asymmetry of nuclear matter on its shear viscosity have been *** to the symmetry energy,the symmetry shear viscosity is defined and its density and temperature dependence are studied.

关键词：剪切粘度核物质不对称弛豫时间相互作用同位旋依赖性丰中子

Comparison of ZnO Films Grown on before- and after-vapor Transport Equilibration (VTE) LiAlO_2 Substrates by Pulsed Laser Deposition (PLD)

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Journal of Materials Science & Technology 2006年第3期22卷 333-335页

作者： jun ZOU Shengming ZHOU jun xu Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai 201800 China Graduate school of Chinese Academy of Sciences Beijing 100039 China

About φ45 mm LiAlO2 single crystal was grown by Czochralski （Cz） technique. However, the full-width at half-maximum （FWHM） value was high to 116.9 arcsec. After three vapor transport equilibration （VTE） processes, we can obtain high-quality LiAlO2 slice with the FWHM value of 44.2 arcsec. ZnO films were fabricated on as-grown slices and after-VTE ones by pulsed laser deposition （PLD）. It was found that ZnO films on the two slices have similar crystallinity, optical transmittance and optical band gap at room temperature. These results not only show that LAO substrate is suitable for ZnO growth, but also prove that the crystal quality of LAO substrate slightly affects the structural and optical properties of ZnO film.

关键词： Crystal structure Pulsed laser deposition ZnO films Vapor transport equilibration (VTE)

Effect of biaxial strain and hydrostatic pressure on the magnetic properties of bilayer CrI_(3)

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Frontiers of physics 2021年第5期16卷 183-190页

作者： Chong xu Qian-jun Wang Bin xu jun Hu School of Physical Science and Technology&Jiangsu Key Laboratory of Thin Films Soochow UniversitySuzhou215006China School of Physical Science and Technology Ningbo UniversityNingbo315211China

Two-dimensional van der Waals magnetic materials are intriguing for applications in the future spintronics devices,so it is crucial to explore strategy to control the magnetic ***,we carried out first-principles calculations and Monte Carlo simulations to investigate the effect of biaxial strain and hydrostatic pressure on the magnetic properties of the bilayer CrI_(3).We found that the magnetic anisotropy,intralayer and interlayer exchange interactions,and Curie temperature can be tuned by biaxial strain and hydrostatic *** compressive biaxial strain may induce a ferromagnetic-to-antiferromagnetic transition of both CrI_(3) *** hydrostatic pressure could enhance the intralayer exchange interaction significantly and hence largely boost the Curie *** effect of the biaxial strain and hydrostatic pressure revealed in the bilayer CrI_(3) may be generalized to other two-dimensional magnetic materials.

关键词： bilayer CrI_(3) biaxial strain hydrostatic pressure magnetic properties