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An Innovative Coupled Common-Node Discrete Element Method-Smoothed Particle Hydrodynamics Model Developed with LS-DYNA and Its Applications

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China Ocean Engineering 2024年第3期38卷 467-482页

作者： SHEN Zhong-xiang WANG Wen-qing XU Cheng-yue LUO Jia-xin LIU ren-wei School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China College of Harbor Coastal and Offshore EngineeringHohai UniversityNanjing 210098China

In this study,a common-node DEM-SPH coupling model based on the shared node method is proposed,and a fluid–structure coupling method using the common-node discrete element method-smoothed particle hydrodynamics(DS-SPH)method is developed using LS-DYNA *** DEM and SPH are established on the same node to create common-node DEM-SPH particles,allowing for fluid–structure *** simulations of various scenarios,including water entry of a rigid sphere,dam-break propagation over wet beds,impact on an ice plate floating on water and ice accumulation on offshore structures,are *** interaction between DS particles and SPH fluid and the crack generation mechanism and expansion characteristics of the ice plate under the interaction of structure and fluid are also *** results are compared with available data to verify the proposed coupling ***,the simulation results demonstrated that controlling the cutoff pressure of internal SPH particles could effectively control particle splashing during ice crushing failure.

关键词： common-node DEM-SPH fluid-structure interaction discrete element method smoothed particle hydrodynamics

New roles of research data infrastructure in research paradigm evolution

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Journal of Data and Information Science 2024年第2期9卷 104-119页

作者： Yizhan Li Lu Dong Xiaoxiao Fan ren wei Shijie Guo Wenzhen Ma Zexia Li National Library Science Chinese Academy of SciencesBeijing 100190China Department of Information Resources Management School of Economics and ManagementUniversity of Chinese Academy of SciencesBeijing100190China Bureau of Facility Support and Budget Chinese Academy of SciencesBeijing 100864China

Research data infrastructures form the cornerstone in both cyber and physical spaces,driving the progression of the data-intensive scientific research *** opinion paper presents an overview of global research data infrastructure,drawing insights from national roadmaps and strategic documents related to research data *** emphasizes the pivotal role of research data infrastructures by delineating four new missions aimed at positioning them at the core of the current scientific research and communication *** four new missions of research data infrastructures are:(1)as a pioneer,to transcend the disciplinary border and address complex,cutting-edge scientific and social challenges with problem-and data-oriented insights;(2)as an architect,to establish a digital,intelligent,flexible research and knowledge services environment;(3)as a platform,to foster the high-end academic communication;(4)as a coordinator,to balance scientific openness with ethics needs.

关键词： Research data infrastructure Landscape Data-centric Problem-oriented

焊接方法对X90管道环焊接头断裂韧性的影响

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焊接学报 2024年第3期45卷 32-42,I0004,I0005页

作者：任伟帅健中国石油大学北京102249

为准确获取X90环焊接头的断裂韧性,采用改进的规则化法对X90环焊接头的低约束单边缺口拉伸试件进行断裂韧性测试,分别从手工焊、自保护药芯半自动焊和气保护药芯半自动焊焊接的X90管道环焊接头中提取测试试件,进行断裂韧性试验.结果表明... 详细信息

为准确获取X90环焊接头的断裂韧性,采用改进的规则化法对X90环焊接头的低约束单边缺口拉伸试件进行断裂韧性测试,分别从手工焊、自保护药芯半自动焊和气保护药芯半自动焊焊接的X90管道环焊接头中提取测试试件,进行断裂韧性试验.结果表明,相同焊接方法下,浅裂纹试件所得阻力曲线比深裂纹试件所得阻力曲线低;热影响区的深裂纹试件具有最高的裂纹扩展阻力曲线,而热影响区的浅裂纹试件具有最低的裂纹扩展阻力曲线;焊缝区试件在试验中极易发生脆断,具有相对较差的断裂性能,并且受焊接方法影响较大,其中气保护药芯焊丝半自动焊的焊缝区试件全部发生脆断.因此,气保护药芯焊丝半自动焊在实际X90管道工程应用中作为参考方法需要优化,这对保持X90管道结构的完整性至关重要.

关键词：焊接方法环焊接头低约束试件阻力曲线断裂韧性

革命如何教育?——红军的政治课程与政治教材

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史林 2024年第1期 191-204,220页

作者：任伟中共中央党校党史部 100091

政治教育是中共革命取得胜利的要因,而政治课则是政治教育的核心手段。中共通过精心设计教材与讲授方法,不仅让课堂变得有趣生动,更重要的是让思想深入人心,打造出了一支有主义的军队。在此过程中,阐明理论,进而把日常行为提升到理论层... 详细信息

政治教育是中共革命取得胜利的要因,而政治课则是政治教育的核心手段。中共通过精心设计教材与讲授方法,不仅让课堂变得有趣生动,更重要的是让思想深入人心,打造出了一支有主义的军队。在此过程中,阐明理论,进而把日常行为提升到理论层次,赋予其更高的意义,是红军政治课的一大诉求。这也契合中共强调的“理论与实践相结合”,即用理论指导实践,让群众超越日常生活,把自身行为纳入更大的历史进程中去,从而进一步激发行动。以后见之明观之,革命时期的政治课堂基本达到了预期目的。

关键词：政治教育政治课红军革命教材

Advancing AI protein structure prediction and design: From amino acid “bones” to new era of all-atom “flesh”

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Green Carbon 2024年第2期2卷 209-210页

作者： Senbiao Fang ren wei Yinglu Cui Lin Su Qingdao Institute of Bioenergy and Bioprocess Technology Chinese Academy of SciencesQingdao 266101China Shandong Energy Institute Qingdao 266101China Qingdao New Energy Shandong Laboratory Qingdao 266101China Junior Research Group Plastic Biodegradation Institute of BiochemistryUniversity of GreifswaldFelix-Hausdorff-Str.8Greifswald 17489Germany AIMCenter Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China Yusuf Hamied Department of Chemistry University of CambridgeCambridge CB21EWUK

With the rapid advancement of Artificial Intelligence(AI)technology,cutting-edge protein structure prediction methods have emerged,exemplified by AlphaFold2 and RoseTTAFold[1].These methods have revolutionized our understanding and utilization of protein structures in biological *** their primary focus lies in predicting the 3D structures of separate protein molecules,the potential of native proteins to perform essential functions through the formation of various"biomolecular assemblies"is *** assemblies involve interactions with other biomolecules including nucleic acids,polysaccharides,metals,small ligands,*** complex bonding mechanisms—ranging from covalent and noncovalent bonding to metal chelation,etc.—between different molecular units play critical roles in maintaining biological activities of these ***,effectively predicting binding interactions between proteins and other(bio)molecules within one biomolecular assembly remains an outstanding ***,one groundbreaking work published in Science by Baker et *** two upgraded deep learning tools:RoseTTAFold All Atom(RFAA)and RFdiffusion All-Atom(RFdiffusionAA)[2],which significantly broaden the in silico construction scope for biomolecule assemblies,enabling researchers to explore complex interactions beyond individual protein structures(Fig.1).

关键词： bonding diffusion breaking

我国高校外语教师对超语教学的态度及其影响因素

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外语界 2024年第1期 32-40页

作者：任伟才华北京航空航天大学外国语学院北京1000191

教师态度对超语实践发挥重要作用。本研究通过问卷调查我国高校外语教师对超语教学的态度及其可能的影响因素。结果显示,高校外语教师对超语教学整体持积极态度,非通用语专业教师的态度最为积极,英语专业教师的态度比公共英语教师积极,... 详细信息

教师态度对超语实践发挥重要作用。本研究通过问卷调查我国高校外语教师对超语教学的态度及其可能的影响因素。结果显示,高校外语教师对超语教学整体持积极态度,非通用语专业教师的态度最为积极,英语专业教师的态度比公共英语教师积极,但后两组教师的态度并无显著性差异。教师的年龄、教龄与其对超语教学的态度不显著相关。研究结果有助于超语研究理论框架完善和我国高校外语教师发展。

关键词：超语超语教学态度外语教师

Structural and Ferroelectric Transition in Few-Layer HfO_(2) Films by First Principles Calculations

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Chinese Physics Letters 2024年第8期41卷 94-106页

作者： Ruiling Gao Chao Liu Bowen Shi Yongchang Li Bing Luo Rui Chen Wenbin Ouyang Heng Gao Shunbo Hu Yin Wang Dongdong Li wei ren Materials Genome Institute State Key Laboratory of Advanced Special SteelShanghai Key Laboratory of High Temperature SuperconductorsInternational Center of Quantum and Molecular StructuresPhysics DepartmentInstitute for the Conservation of Cultural HeritageShanghai UniversityShanghai 200444China Hefei National Research Center for Physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230026China Shanghai World Foreign Language Academy Shanghai 200233China Key Laboratory of Silicate Cultural Relics Conservation(Ministry of Education) Shanghai UniversityShanghai 200444China Hongzhiwei Technology(Shanghai)Co. Ltd.Shanghai 201206China Zhangjiang Laboratory Shanghai 201210China

The discovery of ferroelectricity in HfO_(2)-based materials with high dielectric constant has inspired tremendous research interest for next-generation electronic ***,films structure and strain are key factors in exploration of ferroelectricity in fluorite-type oxide HfO_(2) *** we investigate the structures and straininduced ferroelectric transition in different phases of few-layer HfO_(2) films(layer number𝑁=1–5).It is found that HfO_(2) films for all phases are more stable with increasing films *** them,the Pmn2_(1)(110)-oriented film is most stable,and the films of𝑁=4,5 occur with a𝑃21 ferroelectric transition under tensile strain,resulting in polarization about 11.8μC/cm^(2) along in-plane𝑎-*** ferroelectric transition is caused by the strain,which induces the displacement of Hf and O atoms on the surface to non-centrosymmetric positions away from the original paraelectric positions,accompanied by the change of surface Hf–O bond *** importantly,three new stable HfO_(2)2D structures are discovered,together with analyses of computed electronic structures,mechanical,and dielectric *** work provides guidance for theoretical and experimental study of the new structures and strain-tuned ferroelectricity in freestanding HfO_(2) films.

关键词： properties. ferroelectric positions

任务复杂度对二语学习者互动任务投入的影响研究

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外语教育研究前沿 2024年第1期7卷 60-67,92页

作者：吴依蔓任伟北京航空航天大学

本研究考察了40名中国英语学习者在不同复杂度的互动任务中投入程度的异同,并分析了影响其任务投入的主要因素。研究发现主要有三方面。(1)任务复杂度对学习者投入具有显著影响,但不同维度的任务投入受复杂度的影响不一。复杂任务促使... 详细信息

本研究考察了40名中国英语学习者在不同复杂度的互动任务中投入程度的异同,并分析了影响其任务投入的主要因素。研究发现主要有三方面。(1)任务复杂度对学习者投入具有显著影响,但不同维度的任务投入受复杂度的影响不一。复杂任务促使学生产出更多话轮,更频繁地为同伴提供反馈和帮助,催生更多的积极情绪;而简单任务则促使学生使用更多自我修正,平均每个话轮投入更多时长、产出更大单词量。(2)学习者投入是一个复杂的状态与过程,其子维度之间存在矛盾关系。(3)访谈验证了学习者对任务存在认知参与、社会关联、情绪体验和行为沉浸层面的投入,并揭示了具体的影响因素。

关键词：任务复杂度任务投入同伴互动

第一性原理计算研究γ'-Co3(V,M)(M=Ti,Ta)相的结构稳定性、力学和热力学性质

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物理学报 2024年第8期73卷 261-272页

作者：袁文翎姚碧霞李喜胡顺波任伟上海大学材料基因组工程研究院上海200444 上海大学高品质特殊钢冶金与制备国家实验室上海200444 上海交通大学上海市先进高温材料及精密成形重点实验室上海200240 上海大学文化遗产保护基础科学研究院上海200444 上海大学物理系量子与分子结构国际中心上海200444

本文采用基于密度泛函理论的第一性原理计算方法并结合准谐德拜模型,对Co基高温合金中γ'-Co_(3)(V,M)(M=Ti,Ta)相的结构稳定性、热力学性质以及有限温度下的力学性质进行了系统的研究和讨论.结果表明,γ'-Co_(3)(V,M)相能以L12结构稳... 详细信息

本文采用基于密度泛函理论的第一性原理计算方法并结合准谐德拜模型,对Co基高温合金中γ'-Co_(3)(V,M)(M=Ti,Ta)相的结构稳定性、热力学性质以及有限温度下的力学性质进行了系统的研究和讨论.结果表明,γ'-Co_(3)(V,M)相能以L12结构稳定存在,其具有良好的抵抗变形的能力.γ'-Co_(3)(V,Ti)相的热力学性能对温度的敏感性要大于γ'-Co_(3)(V,Ta)相,且γ'-Co_(3)(V,M)相具有高温稳定性.在有限温度下,随着温度的升高,γ'-Co_(3)(V,M)相由塑性材料向脆性材料过渡转变,而且,除了硬度性能有所提升外,γ'-Co_(3)(V,MM=Ti,Ta)相的力学性能均呈下降趋势.

关键词：高温合金第一性原理结构稳定性热力学性质