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基于迁移学习的LLaMA 2大语言模型微调优化方法

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软件工程 2024年第9期27卷 32-36页

作者：孙倩石竞泽裴丽君张倩怡徐凤强大连东软信息学院辽宁大连116023 大连交通大学软件学院辽宁大连116028

在计算资源受限情况下,针对大语言模型微调面临的训练成本高、微调时间长等问题,提出一种基于迁移学习的预训练大模型的微调优化方法。首先,在原有自注意力验证损失函数中引入权重方向惩罚因子,提高模型收敛速度。其次,改进自注意力验... 详细信息

在计算资源受限情况下,针对大语言模型微调面临的训练成本高、微调时间长等问题,提出一种基于迁移学习的预训练大模型的微调优化方法。首先,在原有自注意力验证损失函数中引入权重方向惩罚因子,提高模型收敛速度。其次,改进自注意力验证优化器,用来平衡不同权重参数的衰减程度。实验结果表明,改进后的微调优化方法可以有效减少微调的迭代次数,提高微调效率,从而提升大语言模型在下游任务的迁移应用能力。

关键词：大语言模型微调优化迁移学习

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Coronary heart disease： incidence, risk factors and interventions in Jiaozhou of Shandong province

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Chinese Medical Journal 2014年第12期127卷 2275-2278页

作者： Yu Hua Li Dan Chu Xianming An Yi Song Tongxun Feng Huixin Lin Peilin Wang Tao Jiang Shaoyan Guo Linlin xu fengqiang Liu Zhengke Yang Bin Department of Cardiology Affiliated Cardiovascular Hospital of Qingdao UniversityQingdaoShandong 266071China Department of Cardiology Affiliated Hospital of Qingdao UniversityQingdaoShandong 266042China Department of Cardiology Jiaozhou Peoples HospitalQingdaoShandong 266300China Department of Cardiology Jiaozhou Puji Central Health InstituteQingdaoShandong 266326China

Background Coronary heart disease （CHD） is the most common type of heart disease and cause of heart *** study investigated the epidemiological characteristics of CHD and its risk factors in Jiaozhou,Shandong province,to ultimately find a way of reducing the prevalence of cardiovascular disease,and to provide a theoretical basis for establishing a cardiovascular disease management path under the regional medical collaborative *** A questionnaire survey was performed including 1 952 people aged 35 years or older who were questioned by means of stratified,cluster,proportional sampling to investigate the prevalence of CHD and its risk *** data were inputted into SPSS11.0 statistical software for processing and *** advised the local medical institutions to establish health files for the residents with CHD and risk *** were followed up *** risk factors and life-style were monitored,and advice was given as to proper *** channels were established,and the patients were transmitted in a timely manner to superior hospitals for better treatment if the necessary treatments were not available in the local *** control of risk factors was observed after the follow-up for half a *** In Jiaozhou,the rates of coronary artery disease,hypertension,diabetes,hyperlipidemia and overweight were 8.15％,28.54％,11.43％,35.46％,and 18.70％ *** rates of hypertension,diabetes,hyperlipidemia and overweight were higher than the data published in ＂The report of Chinese cardiovascular disease 2012＂; which are 24％,9.7％,18.6％,and 9.7％,*** control of risk factors improved significantly after the guidance of the residents lifestyle and medication for six *** The high prevalence of coronary artery disease in Jiaozhou is closely related to age,gender,diet structure,family history of cardiovascular disease,hypertension,diabetes,hyperlipidemia,overweight,and unhealthy ***

关键词： coronary heart disease risk factors prevalence health file regional medical collaboration

Granting strength to aerogel fibers through encapsulation

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Science China Materials 2024年第4期67卷 1365-1366页

作者： Wenhui xu Department of Basic Chemistry School of PharmacyJiangxi University of Chinese MedicineNanchang 330004China

Aerogel fibers, distinguished by their lightweight nature, pronounced porosity, large surface area, and superior thermal insulation properties, have diversified applications in thermal management, energy devices, and environmental remediation[1]. However, compared with monolithic ones, these fibershaped aerogels exhibit limited mechanical strength and resilience due to their one-dimensional small size.

关键词： strength fibers thermal

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Preface for the Special Issue on“Safety and Intelligent Maintenance of Offshore Structures”

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China Ocean Engineering 2024年第2期38卷 181-182页

作者： xu Wan-hai State Key Laboratory of Hydraulic Engineering Intelligent Construction and Operation Tianjin UniversityTianjin 300072China

The ocean serves as a vital carrier for human resource development and economic growth and contains rich mineral resources such as oil,natural gas,polymetallic nodules,cobalt-rich ferromanganese crusts,polymetallic sulfides,and rare earth ***,the ocean has wealthy reserves of wind,wave,tidal,and solar energy,making it an essential strategic space for sustainable future ***,offshore structures are complex.

关键词： ocean offshore tidal

Surface Polarization Effects on Collapse Transition of Polyelectrolyte Brushes

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Chinese Journal of Polymer Science 2024年第9期42卷 1313-1320,I0006页

作者： Xiao-Fei xu State Key Laboratory of Chemical Engineering and School of Chemical Engineering East China University of Science and TechnologyShanghai200237China

Polyelectrolyte brushes(PEBs)are commonly used to modify surface that have attracted great research *** dielectric permittivity of the grafted surface is typically significantly different from that of solution,which results in surface polarization(SP)effect with a jump of electric *** is thus important to study how SP alters the PEB’s structure and *** this work,the SP effects on PEB structure was studied using a statistical thermodynamic *** free energy functional to describe SP effect was constructed by using the image-charge ***,the electrostatic potential was solved from a modified Poisson-Boltzmann equation taking the ion solvation effect into *** the absence of SP,the thickness of PEB exhibited a continuous collapse transition when decreasing the solvent *** the presence of SP,the collapse became a jump-like *** energy analysis showed that the long-range Coulombic interaction dominated the transition because of the enhanced counterion condensation in the presence of *** theory provides an effective tool to study SP effect on PEBs,and the results explain the underlying physics in PEB collapse transition.

关键词： Surface polarization Polyelectrolyte brush Image charge Ion solvation Polyelectrolyte collapse transition

Superior compound coatings prepared by low-temperature vanadium-nitrocarburizing duplex treatment

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Rare Metals 2024年第4期43卷 1828-1835页

作者： Gen Jin Fang-Fang xu xun-xun Hu Yue xu School of Chemistry Beihang UniversityBeijing100191China Guobiao(Beijing)Testing and Certification Co. LtdBeijing100088China School of Materials Science and Engineering Beihang UniversityBeijing100191China

Superior compound coatings were prepared on CK45 steel surface by vanadium-nitrocarburizing duplex treatment in low-temperature salt *** this study,the microhardness,the phase constitution and the compositional distribution in the coatings prepared under different conditions were systematically *** results indicated that the reactions among activated vanadium,carbon and nitrogen atoms occurred on the steel surface,leading to the formation of compound coatings composed of outermost and compound *** mechanism for the formation of compound layer as well as the growth kinetics of the layer was also *** the duplex treatment,the wear and corrosion resistances of steel surface were significantly *** was found that the growth kinetics of compound layer obeyed the parabolic law,with the activation energy of 122.82 kJ·moL^(-1).

关键词： Vanadium-nitrocarburizing duplex treatment Compound coatings Microstructure Formation mechanism Growth kinetics

Optimal design for rubber concrete layered periodic foundations based on the analytical approximations of band gaps and mapping relations

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Earthquake Engineering and Engineering Vibration 2024年第3期23卷 593-608页

作者： Wu Qiaoyun xu Zhifeng xu Peishan Zeng Wenxuan Chen xuyong School of Civil Engineering and Architecture Wuhan Institute of TechnologyWuhan 430073China State Key Laboratory for Health and Safety of Bridge Structures Wuhan 430034China Wuhan Urban Construction Group Co. Ltd.Wuhan 430022China

The seismic performance of rubber concrete-layered periodic foundations are significantly influenced by their design,in which the band gaps play a paramount *** at providing better designs for these foundations,this study first proposes and validates the analytical formulas to approximate the bounds of the first few band *** addition,the mapping relations linking the frequencies of different band gaps are ***,an optimal design method for these foundations is developed,which is validated through an engineering *** is demonstrated that ensuring the superstructure’s resonance zones are completely covered by the corresponding periodic foundation’s band gaps can achieve satisfactory vibration attenuation effects,which is a good strategy for the design of rubber concrete layered periodic foundations.

关键词： periodic foundation band gap vibration attenuation seismic isolation optimal design

Coupling effect on the thermal hazard assessment of hazardous chemical materials via calorimetric technologies and simulation approaches

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Defence Technology（防务技术） 2024年第2期32卷 644-654页

作者： Yabei xu Jiankun Shao Wei Wang Shengliang xu Dongping Chen State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China Science and Technology on Aerospace Chemical Power Laboratory Hubei Institute of Aerospace ChemotechnologyXiangyang 441003China

The coupling effect of heat absorption and release exists in the thermal decomposition of a few chemical ***,the impact of the above coupling on thermal hazard assessment is not considered in the literature *** this work,nitroguanidine(NQ)and 1,3,5-trinitro-1,3,5-triazine(RDX)are selected as representative materials to explore the influence of the coupling effect on the thermal hazard assessment of chemical *** linear heating experiments of NQ and RDX are carried out by a microcalorimeter and synchronous thermal *** thermal decomposition curves are decoupled by advanced thermokinetics *** thermal decomposition and kinetic parameters before and after decoupling are *** results of TG experiment show that both NQ and RDX began to lose mass during the endothermic *** endothermic melting and exothermic decomposition of NQ and RDX are coupled within this *** coupling effect has different degrees of influence on its initial decomposition temperature and safety *** with the parameters in the coupling state,the initial decomposition temperature and adiabatic induction period after decoupling *** self-accelerating decomposition temperature increases,and internal thermal runaway time *** the thermal hazard assessment of chemical materials with coupling effects,the calculated parameters after decoupling should be taken as an important safety index。

关键词： Calorimetric technologies Kinetics Thermal hazard Phase transformation Thermal decomposition

ARPES investigation of the electronic structure and its evolution in magnetic topological insulator MnBi2+2nTe4+3n family

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National Science Review 2024年第2期11卷 81-93页

作者： Runzhe xu Lixuan xu Zhongkai Liu Lexian Yang Yulin Chen State Key Laboratory of Low Dimensional Quantum Physics Department of PhysicsTsinghua University School of Physical Science and Technology Shanghai Tech University and CAS-Shanghai Science Research Center Shanghai Tech Laboratory for Topological Physics Frontier Science Center for Quantum Information Collaborative Innovation Center of Quantum Matter Department of Physics Clarendon LaboratoryUniversity of Oxford

In the past 5 years,there has been significant research interest in the intrinsic magnetic topological insulator family compounds MnBi2+2nTe4+3n（where n=0,1,2…）.In particular,exfoliated thin films of MnBi2Te4have led to numerous experimental breakthroughs,such as the quantum anomalous Hall effect,axion insulator phase and high-Chern number quantum Hall effect without Landau ***,despite extensive efforts,the energy gap of the topological surface states due to exchange magnetic coupling,which is a key feature of the characteristic band structure of the system,remains experimentally *** electronic structure measured by using angle-resolved photoemission （ARPES） shows significant deviation from ab initio prediction and scanning tunneling spectroscopy measurements,making it challenging to understand the transport results based on the electronic *** paper reviews the measurements of the band structure of MnBi2+2nTe4+3nmagnetic topological insulators using ARPES,focusing on the evolution of their electronic structures with temperature,surface and bulk doping and film *** aim of the review is to construct a unified picture of the electronic structure of MnBi2+2nTe4+3ncompounds and explore possible control of their topological properties.

关键词： magnetic topological insulator MnBi2Te4 electronic structure angle-resolved photoemission spectroscopy