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基于模拟-建模研究化学与温度对难熔高熵合金力学行为和变形机制的影响

作者： Fiell peter.等

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Acta Mechanica Sinica 2024年第2期40卷 103-115页

作者：李甲任思危刘彬 peter.K.Liaw 方棋洪 State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body College of Mechanical and Vehicle EngineeringHunan UniversityChangsha410082China State Key Laboratory of Powder Metallurgy Central South UniversityChangsha410083China Department of Materials Science and Engineering The University of TennesseeKnoxville37996USA

难熔高熵合金在高温下表现出优异的性能,突破了传统高温合金的工作温度上限.我们采用原子模拟研究了化学元素分布和温度对等原子比MoNbTaW难熔高熵合金变形机制的影响.根据微观结构演化,建立了基于微观结构的本构模型,定量评估多种强化... 详细信息

难熔高熵合金在高温下表现出优异的性能,突破了传统高温合金的工作温度上限.我们采用原子模拟研究了化学元素分布和温度对等原子比MoNbTaW难熔高熵合金变形机制的影响.根据微观结构演化,建立了基于微观结构的本构模型,定量评估多种强化机制的贡献.结果表明,应变硬化后,流动应力随应变呈锯齿状剧烈波动.由于退火结构的溶质浓度降低,温度升高降低了应变硬化率和流动应力波动幅度.变形孪晶在变形机制中起着关键作用,能够通过位错基塑性和晶粒中的非晶形核进一步调节局部变形.有序结构的存在强烈影响了应力和应变分配.固溶强化和晶界强化对流动应力的贡献很大,孪晶强化对流动压力的贡献很小.原子模拟和力学模型为深入理解难熔高熵合金变形行为及性能的精确预测提供依据.

关键词：流动应力固溶强化强化机制高温合金高熵合金变形机制晶界强化溶质浓度

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人工智能支持的知识导图设计与地理教学备课

地理教学 2024年第13期 12-17页

作者：崔羽 peter.Reimann 南京师范大学江苏南京210023 悉尼大学澳大利亚悉尼2006

本研究利用人工智能的一种自然语言处理技术——语义网络技术,采用学习科学领域中基于设计的研究方法,设计了一款由语义数据库支持的知识导图应用程序,并将其应用于地理教学中。本文以地理学中的水圈知识为例,介绍了学生作为同伴导师设... 详细信息

本研究利用人工智能的一种自然语言处理技术——语义网络技术,采用学习科学领域中基于设计的研究方法,设计了一款由语义数据库支持的知识导图应用程序,并将其应用于地理教学中。本文以地理学中的水圈知识为例,介绍了学生作为同伴导师设计的知识导图形式的备课教案,并阐释了学生导师通过同伴教学备课,实现知识学习和认知提升的理论依据。本研究引入人工智能技术支持的地理教学增强知识导图,作为一种创新策略,旨在促进学生导师的个体学习,同时为集体知识建设做出贡献。

关键词：人工智能语义技术知识导图地理教学备课教案

深度神经网络结合迁移学习和基因遗传算法加速金属团簇结构全局优化

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Chinese Journal of Chemical Physics 2024年第2期37卷 321-329,I0010-I0021,I0104页

作者：杨祁李子玉 peter.L.Rodriguez-Kesslerbr 何圣贵中国科学院化学研究所动态与稳态结构化学国家重点实验室北京100190 墨西哥光学研究中心瓜纳华托37150 中国科学院大学北京100049 北京分子科学国家研究中心中国科学院分子科学科教融合卓越创新中心北京100190

在团簇科学中,搜索金属团簇的全局最小能量结构具有重要的意义.最近,深度神经网络结合迁移学习的全局优化方法被开发出来,以提高金属团簇结构的优化效率,该方法可以大幅减少训练深度神经网络所需的样本数量.为了进一步提高势能面的采样... 详细信息

在团簇科学中,搜索金属团簇的全局最小能量结构具有重要的意义.最近,深度神经网络结合迁移学习的全局优化方法被开发出来,以提高金属团簇结构的优化效率,该方法可以大幅减少训练深度神经网络所需的样本数量.为了进一步提高势能面的采样效率和深度神经网络结合迁移学习的全局优化方法的全局搜索能力,本文提出了一种将基因遗传算法嵌入到深度神经网络结合迁移学习中的全局优化方法.在Pt_(n)(n=9-15)团簇的全局优化中,该方法只需要深度神经网络结合迁移学习的全局优化方法一半的样本数量就能优化得到全局最优结构,同时节省了约70%~80%的计算成本,这表明全局搜索能力的显著提升。在Pt_(14)团簇势能面上的采样结果显示,该方法搜索到低能量的样本(占比25%)比深度神经网络结合迁移学习方法的样本(占比<1%)更多.在Pt_(16)和Pt_(17)团簇的全局最优结构搜索中,本文报道了文献中尚未报道的新结构,证明本论文建立的方法的可行性和先进性.

关键词：全局优化深度神经网络迁移学习基因遗传算法金属团簇铂

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核物质中张量力效应的相对论第一性原理研究

Science Bulletin 2024年第14期69卷 2166-2169页

作者：王锶博童辉王宸璨赵强 peter.Ring 孟杰 Department of Physics and Chongqing Key Laboratory for Strongly Coupled Physics Chongqing UniversityChongqing 401331China Helmholtz Institute for Radiation and Nuclear Physics University of BonnBonn D-53115Germany School of Physics and Astronomy Sun Yat-sen UniversityZhuhai 519082China Center for Exotic Nuclear Studies Institute for Basic ScienceDaejeon 34126South Korea Department of Physics Technical University of MunichGarching D-85747Germany State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871China

As a crucial ingredient of the nucleon-nucleon(NN)interaction,the tensor force has an important impact on the structural and dynamical properties of the nuclear many-body system,particularly the properties of exotic nuclei far away from the stability,which are crucial for understanding the nucleosynthesis in nuclear *** efforts have been devoted to studying the influence of the tensor force in the effective NN interaction in the nuclear medium within the configuration interaction shell model[1]and the density functional theories(DFTs)[2].Due to the difference of modeling the effective NN interaction and the difficulty of determining the tensor-force strengths in finite nuclei,the tensorforce effects in nuclear physics still need to be fully settled.

关键词：张量力核物质 tensor

Oral fluoroquinolones and the risk of Achilles tendon rupture

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Journal of Sport and Health Science 2024年第6期13卷 749-750页

作者： peter.Vibe Rasmussen Jarl Emanuel Strange Anders Holt Department of Cardiology Herlev-Gentofte University HospitalCopenhagen 2730Denmark Department of Cardiology Bispebjerg-Frederiksberg University HospitalCopenhagen 2400Denmark Department of Cardiology Rigshospitalet University HospitalCopenhagen 2100Denmark

Dear editor,Fluoroquinolones(FQs)are a class of antibiotics used to treat bacterial infections,such as lower respiratory,gastrointestinal,and urinary tract *** to its broad-spectrum action and wide availability,it is ... 详细信息

关键词： prescribed spectrum action

Researching Forms of Shadow Education:Methodological Challenges and Complexities of Private Supplementary Tutoring in Myanmar

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ECNU Review of Education 2024年第1期7卷 89-110页

作者： peter.Kamtungtuang Suante Mark Bray The University of Hong Kong East China Normal University&The University of Hong Kong

Purpose:The growing literature on private supplementary tutoring,widely known as shadow education,addresses multiple dimensions and ***,many studies inadequately capture the diversity and implications of different forms of *** paper examines these matters in Myanmar,highlighting complexities and ambiguities in descriptors and in the nature of ***/Approach/Methods:Using a mixed-methods design,this study was conducted in Mandalay Region and Chin *** data were obtained from interviews with I10 Grade II students,34 high school teachers,30 parents,29 private tutoring providers,and two private school ***:The article categorizes tutoring forms based on their styles and orientations,particularly lecture-type teaching and homework supervision by guides,class sizes,durations of fee-charging(e.g,annually),the number of subjects taught per tutor,and tutoring *** study brings the topic out of the shadows for clearer analysis of the phenomenon and thus for assessment of its ***:The study makes a methodological contribution to the wider picture by demonstrating the need for greater clarity and precision in the national and international comparative *** also underscores shortcomings of predetermined categories in questionnaires and the value of qualitative interviews.

关键词： Classification methodology Myanmar private tutoring shadow education

An Interview with peter.Deadman—Acupuncture Pioneer and Founder of The Journal of Chinese Medicine

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Chinese Medicine and Culture 2024年第1期7卷 19-28页

作者： Ioannis Solos Charles Buck peter.Deadman Saint George Clinic and Research Institute Scottsdale 85251the United States of America Northern College of Acupuncture Micklegate YO16LJthe United Kingdom British Acupuncture Council London W129HQthe United Kingdom The Register of Chinese Herbal Medicine London WC1N 3GSthe United Kingdom

This interview was conducted on August 21st, 2022 by Charles Buck and Ioannis Solos. peter.Deadman has worked in the field of health promotion for 50 years. He co-founded Infinity Foods(an organic and natural foods workers co-op) in 1971, followed by the Brighton Natural Health Centre-a charity dedicated to teaching ways to improve personal, community and planetary health and wellbeing. He qualified as an acupuncturist in 1978 and in Chinese herbal medicine in 1990. He founded The Journal of Chinese Medicine(UK) in 1979(Fig. 1), and co-authored A Manual of Acupuncture(published in 1998). He is the author of Live Well Live Long: Teachings from the Chinese Nourishment of Life Tradition. He has taught Chinese medicine and health promotion internationally for decades and is a dedicated practitioner and teacher of Qi Gong(气功).

关键词： Acupuncture Medicine herbal

Cu含量对铁基中熵合金耐腐蚀及抗菌性能的影响

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稀有金属材料与工程 2024年第7期53卷 1817-1825页

作者：赵燕春宋海转马虎文胡若楠冯力段望春 Liaw peter.K 兰州理工大学省部共建有色金属加工与再利用国家重点实验室甘肃兰州730050 兰州理工大学温州泵阀工程研究院浙江温州325105 兰州资源环境职业技术大学甘肃兰州730123 田纳西大学材料系美国诺克斯维尔TN 37996

采用水冷铜坩埚磁悬浮真空熔炼炉制备了(Fe_(63.3)Mn_(14)Si_(9.1)Cr_(9.8)C_(3.8))_(99.5-x)Cu_(x)Ag_(0.5)(x=1,2,3,4,5,at%)合金,并对合金试样进行抗菌时效处理,研究Cu含量对合金耐腐蚀性能以及抗菌性能的影响。结果表明,经过固溶时效处理后的中熵合金均为fcc结构,随着Cu含量的提高,fcc1富铁基体上逐渐析出了富Cu和富Ag的fcc2相。合金在3.5%(质量分数)NaCl溶液中的耐腐蚀性能优于AISI304。随Cu含量的增加,腐蚀电流密度先减小而后增加,容抗弧半径先增大后减小,表明合金的耐腐蚀性能先增强后减弱。合金在大肠杆菌悬浮液中的腐蚀速率呈现出先增大后减小的趋势,x=2合金的耐生物腐蚀能力最优,而抗菌性能和腐蚀性能存在倒置关系。富Cu和富Ag的fcc2相能有效提升合金的抗菌性能,x=5合金的抗菌性能最优,抗菌率达到99.94%.

关键词：中熵合金微观组织腐蚀性能抗菌性能

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可信联邦学习进化优化算法综述

Engineering 2024年第3期34卷 23-42页

作者： Qiqi Liu Yuping Yan Yaochu Jin Xilu Wang peter.Ligeti Guo Yu Xueming Yan School of Engineering Westlake UniversityHangzhou 310030China Faculty of Informatics Department of Computer AlgebraEötvös Loránd UniversityBudapest 1053Hungary Faculty of Technology Bielefeld UniversityBielefeld 33619Germany Institute of Intelligent Manufacturing Nanjing Tech UniversityNanjing 211816China School of Information Science and Technology Guangdong University of Foreign StudiesGuangzhou 510006China

With the development of edge devices and cloud computing,the question of how to accomplish machine learning and optimization tasks in a privacy-preserving and secure way has attracted increased attention over the past *** a privacy-preserving distributed machine learning method,federated learning(FL)has become popular in the last few ***,the data privacy issue also occurs when solving optimization problems,which has received little attention so *** survey paper is concerned with privacy-preserving optimization,with a focus on privacy-preserving data-driven evolutionary *** aims to provide a roadmap from secure privacy-preserving learning to secure privacy-preserving optimization by summarizing security mechanisms and privacy-preserving approaches that can be employed in machine learning and *** provide a formal definition of security and privacy in learning,followed by a comprehensive review of FL schemes and cryptographic privacy-preserving ***,we present ideas on the emerging area of privacy-preserving optimization,ranging from privacy-preserving distributed optimization to privacy-preserving evolutionary optimization and privacy-preserving Bayesian optimization(BO).We further provide a thorough security analysis of BO and evolutionary optimization methods from the perspective of inferring attacks and active *** the basis of the above,an in-depth discussion is given to analyze what FL and distributed optimization strategies can be used for the design of federated optimization and what additional requirements are needed for achieving these ***,we conclude the survey by outlining open questions and remaining challenges in federated data-driven *** hope this survey can provide insights into the relationship between FL and federated optimization and will promote research interest in secure federated optimization.

关键词： Federated learning Privacy-preservation Security Evolutionary optimization Data-driven optimization Bayesian optimization