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Phase-field lattice-Boltzmann study on fully coupled thermal-solute-convection dendrite growth of Al-Cu alloy

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China Foundry 2024年第2期21卷 125-136页

作者： Yin-qi Qiu Meng-wu Wu Xun-peng qin shou-mei Xiong Hubei Key laboratory of Advanced Technology for Automotive Components Wuhan University of TechnologyWuhan 430070China Hubei longzhong laboratory Xiangyang 441000HubeiChina School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China

Dendrite growth is a complex liquid-solid phase transition process involving multiple physical factors.A phase-field lattice-Boltzmann method was developed to simulate the two-and three-dimension dendrite growth of Al-Cu *** effect of fully coupled thermal-solute-convection interaction on the dendrite growth was investigated by incorporating a parallel-adaptive mesh refinement algorithm into the numerical *** accurately reproducing the latent heat release,solute diffusion and convective transport behaviors at the liquidsolid interface,the interaction mechanism among thermal-solute-convection transport as well as their coupling effects on the dendrite growth dynamics were *** simulation results show that the release of latent heat slows down the dendrite growth rate,and both natural and forced convection disrupt the symmetrical growth of *** combination makes the growth of dendrites more complex,capturing important physical aspects such as recalescence,dendrite tip splitting,dendrite tilting,dendrite remelting,and solute plume in the simulation *** on the robustness and powerful ability of the numerical model,the formation mechanisms of these physical aspects were revealed.

关键词： simulation phase field dendrite growth thermal-solute-convection interaction

Data-driven casting defect prediction model for sand casting based on random forest classification algorithm

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China Foundry 2024年第2期21卷 137-146页

作者： Bang Guan Dong-hong Wang Da Shu shou-qin Zhu Xiao-yuan Ji Bao-de Sun Shanghai Key lab of Advanced High-Temperature Materials and Precision Forming School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China State Key lab of Metal Matrix Composites Shanghai Jiao Tong UniversityShanghai 200240China Hefei Casting and Forging Factory of Anhui Heli Co. LtdHefei 230000China State Key laboratory of Materials Processing and Die&Mould Technology Huazhong University of Science and TechnologyWuhan 430074China

The complex sand-casting process combined with the interactions between process parameters makes it difficult to control the casting quality,resulting in a high scrap rate.A strategy based on a data-driven model was proposed to reduce casting defects and improve production efficiency,which includes the random forest(RF)classification model,the feature importance analysis,and the process parameters optimization with Monte Carlo *** collected data includes four types of defects and corresponding process parameters were used to construct the RF *** results show a recall rate above 90% for all *** Gini Index was used to assess the importance of the process parameters in the formation of various defects in the RF ***,the classification model was applied to different production conditions for quality *** the case of process parameters optimization for gas porosity defects,this model serves as an experimental process in the Monte Carlo method to estimate a better temperature *** prediction model,when applied to the factory,greatly improved the efficiency of defect *** show that the scrap rate decreased from 10.16% to 6.68%.

关键词： sand casting process data-driven method classification model quality prediction feature importance

Unveiling the surface-interface properties of perovskite crystals and pivotal regulation strategies

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Nano Research 2024年第5期17卷 3950-3981页

作者： qin li Ziyu Wang Junjie Ma Mengqi Han Peng Gao Meng Cai Yiqiang Zhang Yanlin Song shou Peng Henan Institute of Advanced Technology College of ChemistryZhengzhou UniversityZhengzhou 450001China Key laboratory of Green Printing Institute of ChemistryChinese Academy of Sciences(ICCAS)Beijing 100190China China National Building Material Group Co. Ltd.Beijing 100036China State Key laboratory of Advanced Technology for Float Glass Beijing 100036China

Metal-halide perovskite solar cells have garnered significant research attention in the last decade due to their exceptional photovoltaic performance and potential for *** achieving remarkable power conversion efficiency of up to 26.1%,a substantial discrepancy persists when compared to the theoretical Shockley-Queisser(SQ)*** of the most serious challenges facing perovskite solar cells is the energy loss incurred during photovoltaic conversion,which affects the SQ limits and stability of the *** significant than the energy loss occurring in the bulk phase of the perovskite is the energy loss occurring at the ***,we provide a systematic overview of the physical and chemical properties of the ***,we delve into the underlying mechanism causing the energy deficit and structural degradation at the surface-interface,aiming to enhance the understanding of carrier transport processes and structural chemical ***,we systematically summarized the primary modulating pathways,including surface reconstruction,dimensional construction,and electric-field ***,we propose directions for future research to advance the efficiency of perovskite solar cells towards the radiative limit and their widespread commercial application.

关键词： perovskite solar cells surface-interface treatment defect modification dimensional design energy regulation heterojunction and homojunction

Analysis of acupoint massage combined with touch on relieving anxiety and pain in patients with oral implant surgery

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World Journal of Psychiatry 2024年第4期14卷 533-540页

作者： Jin-Hong Qu Cheng-Cheng shou Xin He qin Wang Yue-Xia Fang Department of Stomatology Hangzhou Lin'an Traditional Chinese Medicine HospitalHangzhou 311300Zhejiang ProvinceChina Department of Software R&D Hangzhou Broadlink Technology CoLtd.Hangzhou 311300Zhejiang ProvinceChina Department of Stomatology Hangzhou Red Cross HospitalHangzhou 310003Zhejiang ProvinceChina Department of Cardiovascular Hangzhou Lin'an Traditional Chinese Medicine HospitalHangzhou 311300Zhejiang ProvinceChina Department of Traditional Chinese Medicine Development Hangzhou Lin'an Traditional Chinese Medicine HospitalHangzhou 311300Zhejiang ProvinceChina

BACKGROUND Oral implant surgery is an effective procedure for artificial implants in missing tooth areas under local *** patients under local anesthesia are conscious during this procedure,compared with general anesthesia-related operations,they are more likely to experience negative emotions,such as anxiety and *** emotional reactions result in shivering and chills in the limbs,leading to poor doctor-patient cooperation and even avoidance of *** traditional Chinese medicine,it is believed that acupoint massage regulates blood and Qi,dredge menstruation,and relieve pain,which is beneficial for patients’emotional adjustment;however,there are few related clinical *** To observe the changes in anxiety and pain in patients with oral implant after acupoint massage combined with touch *** One hundred patients undergoing oral implantation in our hospital between May 2020 and May 2023 were randomly divided into control and study groups,according to a random number table,with 50 patients in each *** control group received routine intervention,and the study group received acupoint massage combined with touch on the basis of the control ***[assessed using the Modified Dental Anxiety Scale(MDAS)],pain severity,blood pressure,heart rate,and satisfaction were compared between the two *** Before intervention,the difference in MDAS score between the two groups was not significant(P>0.05),while after the intervention,the MDAS scores decreased in both groups compared with those before the intervention(Plower than that of the control group,with a statistically significant difference(Ply lower than that in the control group(Plic and diastolic blood pressures or heart rate between the two groups(P>0.05).The systolic and d

关键词： Oral implant Acupoint massage Touch Anxiety Degree of pain

Combined Modeling of Shear-Induced Cell Aggregation and Adhesion Dynamics Mediated by Receptor-ligand Interactions

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Combined Modeling of Shear-Induced Cell Aggregation and Adhe...

第十届全国生物力学学术会议暨第十二届全国生物流变学学术会议

作者： Yu Du shou-qin lü Yu-hong Cui Yan Zhang Mian long Key laboratory of Microgravity(National Microgravity laboratory) Institute of MechanicsChinese Academy of Sciences Center of Biomechanics and Bioengineering Institute of MechanicsChinese Academy of Sciences Department of Mechanics Tianjin University

Blood cell aggregation and adhesion to endothelial cells under shear flow are crucial to many biological processes such as thrombi formation,inflammatory cascade,and tumor metastasis, in which these cellular interactions are mainly mediated by dynamics and kinetics of underlying receptor-ligand *** the theoretical modeling of aggregation dynamics and adhesion kinetics of interacting cells have been well studied separately,how to couple these two processes remains poorly understood. Here we developed a unified framework that couples cellular aggregation dynamics and ad-

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功能玻璃关键材料体系发展战略研究

中国工程科学 2024年第3期26卷 10-18页

作者：彭寿秦旭升洪伟吴波黄毅中国建材集团有限公司北京100036 玻璃新材料创新中心(安徽)有限公司安徽蚌埠233000 中建材玻璃新材料研究院集团有限公司安徽蚌埠233000

功能玻璃材料是无机非金属材料的重要组成,主要包括电子信息玻璃、新能源玻璃、特种玻璃等,是信息显示、半导体、新能源、深海、深空等战略性新兴产业的基础性支撑性材料,已成为我国建设智能社会、低碳社会的重要基石。我国近年来在功... 详细信息

功能玻璃材料是无机非金属材料的重要组成,主要包括电子信息玻璃、新能源玻璃、特种玻璃等,是信息显示、半导体、新能源、深海、深空等战略性新兴产业的基础性支撑性材料,已成为我国建设智能社会、低碳社会的重要基石。我国近年来在功能玻璃领域取得一系列重大成就,但仍存在关键材料短板环节突出、跟踪研发、创新资源分散、体系化发展不足等问题。本文按照主干化、体系化研究思路,围绕电子信息玻璃、新能源玻璃、特种玻璃等关键材料的技术、产业、支撑等体系化发展要素,梳理了国外功能玻璃领域先进国家的发展现状,结合我国的发展现状,凝炼了我国功能玻璃关键材料发展面临的主要问题,提出了我国功能玻璃关键材料的发展思路与近期、中期、远期的发展目标,凝练了我国功能玻璃关键材料领域的重点技术发展方向。研究建议:增强关键原材料保障能力,为产业安全发展提供有力支撑;加速启动功能玻璃关键材料创新滚动规划;强化功能玻璃关键材料政策支撑;完善功能玻璃关键材料的绿色低碳与数字化发展。

关键词：无机非金属材料功能玻璃电子信息玻璃新能源玻璃特种玻璃

基于DIC方法的混凝土结构裂缝开展全局识别与重构

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中国公路学报 2024年第3期37卷 283-297页

作者：晏班夫寇宇航秦筵越罗磊李寿科李水生湖南大学土木工程学院湖南长沙410082 广西大学土木建筑工程学院广西南宁530004 湖南科技大学土木工程学院湖南湘潭411201 中国建筑第五工程局有限公司湖南长沙410011

裂缝的全局动态识别对揭示混凝土结构的破坏机理十分重要。为解决传统单点位移及应变测试手段难以实现全局裂缝识别的问题,提出了一种基于数字图像相关(Digital Image Correlation, DIC)对混凝土结构裂缝开展全局识别与重构的方法。通... 详细信息

裂缝的全局动态识别对揭示混凝土结构的破坏机理十分重要。为解决传统单点位移及应变测试手段难以实现全局裂缝识别的问题,提出了一种基于数字图像相关(Digital Image Correlation, DIC)对混凝土结构裂缝开展全局识别与重构的方法。通过设置裂缝识别阈值,在DIC位移场中按水平方向逐行逐点识别表征开裂位置的位移突变点,随后对开裂位置两侧位移向量作差得到裂缝水平缝宽,再通过局部最小二乘拟合得到裂缝开展走向,根据水平缝宽与裂缝走向关系得到开裂处实际宽度。对位移场内所有目标点执行上述操作即可实现对裂缝形态的全局识别与动态重构。针对图像噪声问题,通过模拟试验验证了位移场降噪的必要性;采用均方根误差、信噪比与平滑度指标量化分析了不同降噪方法的去噪效果。针对实际工程中最优裂缝识别阈值的选取问题,引入信息熵与相关系数,基于缝宽分布熵值曲线与识别损失相关系数曲线提出了最优阈值的确定方法。最后通过超高性能混凝土加固混凝土梁加载试验进行验证。结果表明:该方法实现了混凝土结构裂缝开展过程的自动测量与可视化展示,与裂缝观测仪的对比测试结果表明缝宽测量误差在0.01 mm以内,满足工程要求。该研究为工程结构加载试验提供了一种非接触、可视化、精确的裂缝全局测量手段。

关键词：桥梁工程混凝土结构裂缝识别数字图像相关裂缝重构位移场降噪

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智能模糊测试综述:问题探索和方法分类

计算机学报 2024年第9期47卷 2059-2083页

作者：王琴应许嘉诚李宇薇潘祖烈张玉清张超纪守领浙江大学计算机科学与技术学院浙江大学控制科学与工程学院国防科技大学电子对抗学院中国科学院大学国家计算机网络入侵防范中心清华大学网络研究院

随着近年来软件系统规模以及复杂性的增加,安全漏洞数量持续增长、影响面逐步扩大,全球安全形势依然严峻.针对该问题,学术界和工业界致力于研究高效的漏洞挖掘技术,提前发现和修复潜在的漏洞.其中模糊测试作为先进的漏洞挖掘技术之一,... 详细信息

随着近年来软件系统规模以及复杂性的增加,安全漏洞数量持续增长、影响面逐步扩大,全球安全形势依然严峻.针对该问题,学术界和工业界致力于研究高效的漏洞挖掘技术,提前发现和修复潜在的漏洞.其中模糊测试作为先进的漏洞挖掘技术之一,吸引了学术界和工业界的广泛关注.为了进一步提高漏洞挖掘的能力,研究人员提出了智能模糊测试,即利用人工智能和程序分析等技术作为辅助,从而实现对复杂软件系统更高效的测试和分析并智能引导漏洞挖掘方向.本文回顾了近八年来智能模糊测试研究进展,提出了一个通用模糊测试流程模型和问题导向的智能模糊技术分类方法,从优化测试输入生成、提高测试效率以及增强测试预言机三个方面总结了当前智能模糊测试的优势和不足之处,最后对智能模糊测试面临的挑战和未来研究方向进行展望和总结.

关键词：模糊测试软件与系统安全漏洞挖掘人工智能程序分析

明代府州县的繁简与等级划分——以江西为中心的考察

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史学集刊 2024年第3期 19-34页

作者：高寿仙中共北京市委党校北京市情研究中心北京100044

从秦汉到元朝,皆以户口数量为主要指标,兼顾政治地位、地理位置、经济水平等因素,把地方政区划分为若干等级。明太祖一改前代做法,先是以税粮为标准把府州县分为上中下三等,旋即又综合考虑税粮多少以及地理冲僻、事务繁简、负担轻重等... 详细信息

从秦汉到元朝,皆以户口数量为主要指标,兼顾政治地位、地理位置、经济水平等因素,把地方政区划分为若干等级。明太祖一改前代做法,先是以税粮为标准把府州县分为上中下三等,旋即又综合考虑税粮多少以及地理冲僻、事务繁简、负担轻重等因素把府州县分为繁简两等,开启了主要依照事务繁简和地理冲僻等因素划分政区等第的新趋向。到明代后期,繁简两分法被进一步发展为上中下三等制。从江西各府州县的相关资料看,上、中、下等级与政务繁简、道里冲僻、治理难易等因素之间具有一定的对应关系,但这种对应并不严格,说明政区等级评定是个非常复杂的问题,无论采用何种标准都难全部适用。

关键词：明代政区分等繁简制三等制