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Journal of Innovative Optical Health Sciences 2024年第2期17卷 35-44页

作者： Zenan Zhou Huanhuan Yu Jiaqing Zhao xiangning wang Qiang Wu Cuixia Dai Shanghai Institute of Technology Shanghai P.R.China Shanghai Sixth People'sHospital Affiliated to Shanghai Jiao Tong University School of Medicine Shanghai P.R.China

Diabetic retinopathy(DR)is one of the major causes of visual impairment in adults with diabetes.Optical coherence tomography angiography(OCTA)is nowadays widely used as the golden criterion for diagnosing DR.Recently,wide-field OCTA(WF-OCTA)provided more abundant information including that of the peripheral retinal degenerative changes and it can contribute in accurately diagnosing DR.The need for an automatic DR diagnostic system based on WF-OCTA pictures attracts more and more attention due to the large diabetic population and the prevalence of retinopathy cases.In this study,automatic diagnosis of DR using vision transformer was performed using WF-OCTA images(12 mm×12 mm single-scan)centered on the fovea as the dataset.WF-OCTA images were automatically classified into four classes:No DR,mild nonproliferative diabetic retinopathy(NPDR),moderate to severe NPDR,and proliferative diabetic retinopathy(PDR).The proposed method for detecting DR on the test set achieves accuracy of 99.55%,sensitivity of 99.49%,and specificity of 99.57%.The accuracy of the method for DR staging reaches up to 99.20%,which has been proven to be higher than that attained by classical convolutional neural network models.Results show that the automatic diagnosis of DR based on vision transformer and WF-OCTA pictures is more effective for detecting and staging DR.

关键词： Wide field optical coherence tomography angiography diabetic retinopathy vision transformer image classification

Computational Experiments for Complex Social Systems:Integrated Design of Experiment System

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1175-1189页

作者： Xiao Xue xiangning Yu Deyu Zhou Xiao wang Chongke Bi Shufang wang Fei-Yue wang College of Intelligence and Computing Tianjin UniversityTianjin 300350China School of Software Shandong UniversityJinan 250101China School of Artificial Intelligence Anhui UniversityHefei 230601China School of Geographic and Environmental Sciences Tianjin Normal UniversityTianjin 300387China Institute of Automation Chinese Academy of Sciences Beijing 100190China

Powered by advanced information industry and intelligent technology,more and more complex systems are exhibiting characteristics of the cyber-physical-social systems(CPSS).And human factors have become crucial in the operations of complex social systems.Traditional mechanical analysis and social simulations alone are powerless for analyzing complex social systems.Against this backdrop,computational experiments have emerged as a new method for quantitative analysis of complex social systems by combining social simulation(e.g.,ABM),complexity science,and domain knowledge.However,in the process of applying computational experiments,the construction of experiment system not only considers a large number of artificial society models,but also involves a large amount of data and knowledge.As a result,how to integrate various data,model and knowledge to achieve a running experiment system has become a key challenge.This paper proposes an integrated design framework of computational experiment system,which is composed of four parts:generation of digital subject,generation of digital object,design of operation engine,and construction of experiment system.Finally,this paper outlines a typical case study of coal mine emergency management to verify the validity of the proposed framework.

关键词： artificial system operations

Computational Experiments for Complex Social Systems:Experiment Design and Generative Explanation

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 1022-1038页

作者： Xiao Xue Deyu Zhou xiangning Yu Gang wang Juanjuan Li Xia Xie Lizhen Cui Fei-Yue wang the School of Computer Software College of Intelligence and ComputingTianjin UniversityTianjin 300350China the School of Software and the Joint SDUNTU Centre for Artificial Intelligence Research(C-FAIR) Shandong UniversityJinan 250101China the Information School Xi’an University of Financial and EconomicsXi’an 710100China the State Key Laboratory of Multimodal Artificial Intelligence Systems Institute of AutomationChinese Academy of SciencesBeijing 100190China Hainan University Haikou 570228China the State Key Laboratory for Management and Control of Complex Systems Institute of AutomationChinese Academy of SciencesBeijing 1001901China

Powered by advanced information technology,more and more complex systems are exhibiting characteristics of the cyber-physical-social systems(CPSS).In this context,computational experiments method has emerged as a novel approach for the design,analysis,management,control,and integration of CPSS,which can realize the causal analysis of complex systems by means of“algorithmization”of“counterfactuals”.However,because CPSS involve human and social factors(e.g.,autonomy,initiative,and sociality),it is difficult for traditional design of experiment(DOE)methods to achieve the generative explanation of system emergence.To address this challenge,this paper proposes an integrated approach to the design of computational experiments,incorporating three key modules:1)Descriptive module:Determining the influencing factors and response variables of the system by means of the modeling of an artificial society;2)Interpretative module:Selecting factorial experimental design solution to identify the relationship between influencing factors and macro phenomena;3)Predictive module:Building a meta-model that is equivalent to artificial society to explore its operating laws.Finally,a case study of crowd-sourcing platforms is presented to illustrate the application process and effectiveness of the proposed approach,which can reveal the social impact of algorithmic behavior on“rider race”.

关键词： Agent-based modeling computational experiments cyber-physical-social systems(CPSS) generative deduction generative experiments meta model

Effects of microstructure characteristics on the tensile properties and fracture toughness of TA15 alloy fabricated by hot isostatic pressing

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International Journal of Minerals,Metallurgy and Materials 2023年第4期30卷 697-706页

作者： Langping Zhu Yu Pan Yanjun Liu Zhiyu Sun xiangning wang Hai Nan Muhammad-Arif Mughal Dong Lu Xin Lu Beijing Advanced Innovation Center for Materials Genome Engineering Institute of Engineering TechnologyUniversity of Science and Technology BeijingBeijing 100083China AECC Beijing Institute of Aeronautical Materials Beijing 100095China Beijing Engineering Research Center of Advanced Titanium Alloy Precision Forming Technology Beijing 100095China Institute of Artificial Intelligence University of Science and Technology BeijingBeijing 100083China Sichuan Advanced Metal Material Additive Manufacturing Engineering Technology Research Center Chengdu Advanced Metal Materials Industry Technology Research Institute Co.LtdChengdu 610300China

Powder hot isostatic pressing(HIP) is an effective method to achieve near-net-shape manufacturing of high-quality complex thinwalled titanium alloy parts, and it has received extensive attention in recent years. However, there are few reports about the microstructure characteristics on the strengthening and toughening mechanisms of powder hot isostatic pressed(HIPed) titanium alloys. Therefore, TA15powder was prepared into alloy by HIP approach, which was used to explore the microstructure characteristics at different HIP temperatures and the corresponding tensile properties and fracture toughness. Results show that the fabricated alloy has a “basket-like structure” when the HIP temperature is below 950℃, consisting of lath clusters and surrounding small equiaxed grains belts. When the HIP temperature is higher than 950℃, the microstructure gradually transforms into the Widmanstatten structure, accompanied by a significant increase in grain size. The tensile strength and elongation are reduced from 948 MPa and 17.3% for the 910℃ specimen to 861 MPa and 10% for the 970℃ specimen.The corresponding tensile fracture mode changes from transcrystalline plastic fracture to mixed fracture including intercrystalline cleavage.The fracture toughness of the specimens increases from 82.64 MPa·m^(1/2)for the 910℃ specimen to 140.18 MPa·m^(1/2)for the 970℃ specimen.Specimens below 950℃ tend to form holes due to the prior particle boundaries(PPBs), which is not conducive to toughening. Specimens above 950℃ have high fracture toughness due to the crack deflection, crack branching, and shear plastic deformation of the Widmanstatten structure. This study provides a valid reference for the development of powder HIPed titanium alloy.

关键词： powder titanium alloy hot isostatic pressing strength fracture toughness

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普惠金融对经济增长与城乡收入差距的影响

统计与决策 2024年第6期40卷 145-150页

作者：王澜王相宁中国科学技术大学管理学院合肥230026

为考察普惠金融对经济增长与城乡收入差距的影响,文章选取2013—2020年我国31个省份的面板数据,通过纳入债券、股票等直接融资工具指标构建普惠金融指数,并利用静态面板可行广义最小二乘回归模型、动态面板广义矩回归模型,研究全国以及... 详细信息

为考察普惠金融对经济增长与城乡收入差距的影响,文章选取2013—2020年我国31个省份的面板数据,通过纳入债券、股票等直接融资工具指标构建普惠金融指数,并利用静态面板可行广义最小二乘回归模型、动态面板广义矩回归模型,研究全国以及东、中、西部地区普惠金融发展水平对经济增长与城乡收入差距的影响。结果表明:总体来看,普惠金融与经济增长存在“U”型关系,普惠金融与城乡收入差距存在“倒U”型关系。分地区来看,普惠金融对经济增长与城乡收入差距的影响均表现出一定程度的区域异质性。

关键词：普惠金融经济增长城乡收入差距非线性关系

1920-1950年代“建筑艺术”词义演变考

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建筑学报 2024年第4期 92-98页

作者：王雪睿李翔宁同济大学建筑与城市规划学院上海200092

以语义学与语用学作为建筑理论史的潜在分析框架,考察1920-1950年代间“建筑艺术”概念在中国建筑界发生的意义演变。在回顾中国传统建筑观念的基础上,指出“建筑艺术”一词是近代中国建筑师特有的语义创造;1950年代,“建筑艺术”概念... 详细信息

以语义学与语用学作为建筑理论史的潜在分析框架,考察1920-1950年代间“建筑艺术”概念在中国建筑界发生的意义演变。在回顾中国传统建筑观念的基础上,指出“建筑艺术”一词是近代中国建筑师特有的语义创造;1950年代,“建筑艺术”概念则经历了从被特殊强调到遭受批判的复杂变迁。通过分析“建筑艺术”在不同时代语境中的表意与翻译,旨在为理解“建筑”与“艺术”之间的关联提供批判性的解读框架。

关键词：建筑艺术建筑理论词义演变中国现代建筑观念史

北极真菌Penicillium sp.MYA5次级代谢产物研究

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中国海洋药物 2024年第2期43卷 73-78页

作者：翟祥宁王斌浙江海洋大学食品与药学学院浙江舟山316022

目的对来源于北极斯瓦尔巴德群岛的真菌Penicillium sp.MYA5的次级代谢产物进行研究。方法对菌株进行规模发酵,采用正相硅胶、反相十八烷基硅烷键合硅胶填料ODS、高效液相(HPLC)等色谱方法对发酵液的乙酸乙酯萃取部位进行系统分离纯化,... 详细信息

目的对来源于北极斯瓦尔巴德群岛的真菌Penicillium sp.MYA5的次级代谢产物进行研究。方法对菌株进行规模发酵,采用正相硅胶、反相十八烷基硅烷键合硅胶填料ODS、高效液相(HPLC)等色谱方法对发酵液的乙酸乙酯萃取部位进行系统分离纯化,通过核磁共振谱(NMR)、质谱(MS)旋光、电子圆二色谱(ECD)等波谱分析方法,并与相关文献比较,鉴定化合物结构。结果分离得到7个化合物,经鉴定化合物1~7分别为penicophenone C(1)、communol G(2)、1-(2,4-dihydroxy-5-methylphenyl)ethan-1-one(3)、penicophenone A(4)、conidiogenones C(5)、cis-3,4-dihydro-3,4,8-trihydroxynaphthalen-1(2H)-one(6)、(-)-(3S)-3-hydroxy-3-methyloxindole(7)。结论化合物1是新化合物,为苯并吡喃类衍生物,是已知化合物(Z)-6-acetyl-3-(1,2-dihydroxypropylidene)-5-hydroxy-8-methylchroman-2-one的同分异构体,且首次确定了该已知化合物的绝对构型;化合物5对人急性早幼粒白血病细胞HL-60以及人肝癌细胞BEL-7402有着很强的细胞毒活性,半抑制浓度(IC50)分别为0.44和1.16μmol/L。

关键词：北极真菌青霉属次级代谢产物苯并吡喃类衍生物

Progress in efficient doping of Al-rich AlGaN

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Journal of Semiconductors 2024年第2期45卷 10-20页

作者： Jiaming wang Fujun Xu Lisheng Zhang Jing Lang Xuzhou Fang Ziyao Zhang Xueqi Guo Chen Ji Chengzhi Ji Fuyun Tan Xuelin Yang xiangning Kang Zhixin Qin Ning Tang Xinqiang wang Weikun Ge Bo Shen State Key Laboratory of Artificial Microstructure and Mesoscopic Physics School of PhysicsPeking UniversityBeijing 100871China Beijing SinoGaN Semiconductor Technology Co. Ltd.Beijing 101399China Nano-optoelectronics Frontier Center of Ministry of Education Peking UniversityBeijing 100871China Collaborative Innovation Center of Quantum Matter Beijing 100871China

The development of semiconductors is always accompanied by the progress in controllable doping techniques.Taking AlGaN-based ultraviolet(UV)emitters as an example,despite a peak wall-plug efficiency of 15.3%at the wavelength of 275 nm,there is still a huge gap in comparison with GaN-based visible light-emitting diodes(LEDs),mainly attributed to the inefficient doping of AlGaN with increase of the Al composition.First,p-doping of Al-rich AlGaN is a long-standing challenge and the low hole concentration seriously restricts the carrier injection efficiency.Although p-GaN cladding layers are widely adopted as a compromise,the high injection barrier of holes as well as the inevitable loss of light extraction cannot be neglected.While in terms of n-doping the main issue is the degradation of the electrical property when the Al composition exceeds 80%,resulting in a low electrical efficiency in sub-250 nm UV-LEDs.This review summarizes the recent advances and outlines the major challenges in the efficient doping of Al-rich AlGaN,meanwhile the corresponding approaches pursued to overcome the doping issues are discussed in detail.

关键词： AlGaN-based UV-LEDs Al-rich AlGaN doping

1987-2022年黄河银川平原段河道演变特征及影响因素

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干旱区资源与环境 2024年第3期38卷 92-103页

作者：张伊婧璩向宁王磊王筱平谭鹏宁夏大学生态环境学院银川750021 宁夏大学/西北土地退化与生态系统恢复国家重点实验室培育基地银川750021 宁夏大学/西北退化生态系统恢复与重建教育部重点实验室银川750021 宁夏黄河湿地生态系统国家定位观测研究站银川750011

研究黄河银川平原段河道的演变特征,对河道的保护提供理论依据。文中基于1987-2022年8期Landsat卫星影像,利用修正的归一化水体指数对黄河河道进行提取,计算不同时期的河道宽度、河道面积、摆动幅度以及摆动速率,分析35年间黄河银川平... 详细信息

研究黄河银川平原段河道的演变特征,对河道的保护提供理论依据。文中基于1987-2022年8期Landsat卫星影像,利用修正的归一化水体指数对黄河河道进行提取,计算不同时期的河道宽度、河道面积、摆动幅度以及摆动速率,分析35年间黄河银川平原段的摆动特征及变化规律。结果表明:35年间,河道宽度平均减小0.36km,河段面积平均减小0.66km^(2)。河道左岸平均每年向右摆动0.10km,R1、R2、R3河段左岸向左向右的摆动速率之比分别为1:2.12:2.53和1:4.19:5.33;河道右岸平均每年向右摆动0.004km,R1、R2、R3段河道右岸向左向右平均摆动速率之比分别为1:0.82:2.16和1:1.90:3.19。河道整体呈萎缩趋势且向右偏移,黄河银川平原段下游摆动变化程度更为严重。河道在时间上的变化可能与自然因素与人类筑坝蓄水等人类活动相关,在空间上的变化可能受制于河道径流及河岸物质组成的差异。对于黄河银川平原河段,防护建设应重点关注在下游河段。

关键词：河岸河道摆动堤岸防护黄河

50 kHz/200 kHz声场水中疏水颗粒的瞬态及稳态团聚规律

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声学学报 2024年第1期49卷 146-154页

作者：陈昱冉胡悦卜祥宁何季麟郑州大学材料科学与工程学院郑州450001 河南省资源环境调查三院郑州450046 中国矿业大学化工学院徐州221116

针对超声场存在的瞬态及稳态两种疏水颗粒团聚行为,分别选取50 kHz与200 kHz两个频率,通过高速摄像机对不同的声团聚现象进行观测,对比了瞬态及稳态团聚在团聚位置、速度及聚团形态、数量、强度等方面的差异,并从声辐射力和空化的角度... 详细信息

针对超声场存在的瞬态及稳态两种疏水颗粒团聚行为,分别选取50 kHz与200 kHz两个频率,通过高速摄像机对不同的声团聚现象进行观测,对比了瞬态及稳态团聚在团聚位置、速度及聚团形态、数量、强度等方面的差异,并从声辐射力和空化的角度分析了瞬态及稳态团聚不同的形成机制。研究结果表明,50 kHz声场与200 kHz声场分别引起瞬态和稳态声团聚,两种声团聚方式的行为和形成机制均存在较大差异。

关键词：声团聚疏水颗粒空化气泡声辐射力