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部分预制装配型钢混凝土柱轴压性能试验研究

建筑结构学报 2021年第S2期42卷 220-227页

作者：陈阳杨勇上海大学土木工程系上海200444 西安建筑科技大学土木工程学院陕西西安710055

为研究部分预制装配型钢混凝土(PPSRC)柱在轴向荷载作用下的受力性能,对9根PPSRC柱(其中7根PPSRC实心柱和2根PPSRC空心柱)和1根现浇型钢混凝土柱进行静力加载试验,研究内部混凝土强度、配箍率和型钢翼缘是否焊接栓钉等参数对其破坏形态... 详细信息

为研究部分预制装配型钢混凝土(PPSRC)柱在轴向荷载作用下的受力性能,对9根PPSRC柱(其中7根PPSRC实心柱和2根PPSRC空心柱)和1根现浇型钢混凝土柱进行静力加载试验,研究内部混凝土强度、配箍率和型钢翼缘是否焊接栓钉等参数对其破坏形态、荷载-位移曲线以及轴向承载力的影响。基于Mander模型,分析了型钢对混凝土的约束作用,建立了考虑不同约束区混凝土轴心抗压强度差异的PPSRC柱轴压承载力计算方法。试验结果表明:型钢与预制混凝土、现浇混凝土之间共同作用良好;实心柱和空心柱破坏形态相近,破坏时均在柱中部呈现混凝土的压溃脱落现象;随着内部混凝土强度的提高和箍筋间距的缩小,柱承载力呈上升趋势,但受型钢翼缘是否焊接栓钉影响不大。最后基于强度叠加方法建立了PPSRC柱轴压承载力计算公式,并根据试验结果验证了其准确性。

关键词：装配式结构型钢混凝土柱约束模型静力试验轴压性能

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环糊精超分子组装体与核酸的相互作用

有机化学 2012年第5期32卷 805-814页

作者：陈湧刘育南开大学化学系、元素有机化学国家重点实验室天津300071

环糊精是一类由6～8个D-型葡萄糖连接而成的环聚多糖分子,目前已广泛应用于化学和生物学的许多领域.综述了一些生物活性的环糊精超分子组装体,如环糊精假聚轮烷、环糊精/金纳米粒子组装体、环糊精/富勒烯组装体、环糊精/碳纳米管组装体... 详细信息

环糊精是一类由6～8个D-型葡萄糖连接而成的环聚多糖分子,目前已广泛应用于化学和生物学的许多领域.综述了一些生物活性的环糊精超分子组装体,如环糊精假聚轮烷、环糊精/金纳米粒子组装体、环糊精/富勒烯组装体、环糊精/碳纳米管组装体等的构筑及其与核酸的相互作用,如对核酸的切割、凝聚、传递作用和对核酸酶的抑制作用等方面的研究进展.

关键词：环糊精核酸超分子组装体

基于基扩展模型的UKF-RTSS高可靠鲁棒V2V信道估计

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电子与信息学报 2022年第5期44卷 1792-1799页

作者：廖勇陈颖重庆大学微电子与通信工程学院重庆400044

车联网应用场景对无线通信在带宽、时延、可靠性方面提出了更高的需求,特别是车辆对车辆(Vehicle to Vehicle,V2V)场景。针对V2V高速移动场景,时/频域选择性衰落(双选衰落)和非平稳特性给信道估计带来的技术挑战,该文提出了一种基于基... 详细信息

车联网应用场景对无线通信在带宽、时延、可靠性方面提出了更高的需求,特别是车辆对车辆(Vehicle to Vehicle,V2V)场景。针对V2V高速移动场景,时/频域选择性衰落(双选衰落)和非平稳特性给信道估计带来的技术挑战,该文提出了一种基于基扩展模型(Basis Expansion Model,BEM)的UKF-RTSS(Unscented Kalman Filter-Rauch-Tung-Striebel Smoother)信道估计方法。该方法采用BEM拟合快时变信道,将信道参数的估计转化为基函数系数的估计;通过无迹卡尔曼滤波(UKF),联合估计数据处信道冲激响应与时域自相关系数,用于追踪快时变的信道响应。为了进一步提升信道估计的精度,引入RTSS对后向信道状态信息进行信道估计和插值,与UKF构成了“滤波和平滑”结构的UKF-RTSS联合估计器。系统仿真分析表明,在不同速度的快时变条件下,所提方法相比其他经典方法具有更高的信道估计精度和鲁棒性,特别适用于车联网下的无线通信场景。

关键词： V2V 信道估计基扩展模型无迹卡尔曼滤波联合估计

Analysis and comparison of retinal vascular parameters under different glucose metabolic status based on deep learning

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International Journal of Ophthalmology(English edition) 2024年第9期17卷 1581-1591页

作者： Yan Jiang Di Gong Xiao-Hong chen Lin Yang Jing-Jing Xu Qi-Jie Wei Bin-Bin chen yong-Jiang Cai Wen-Qun Xi Zhe Zhang Departments of Laboratory Medicine the Second Affiliated HospitalZhejiang University School of MedicineHangzhou 310009Zhejiang ProvinceChina Shenzhen Eye Hospital Jinan UniversityShenzhen 518040Guangdong ProvinceChina Center of Health Management Peking University Shenzhen HospitalShenzhen 518036Guangdong ProvinceChina Visionary Intelligence Ltd. Beijing 100080China Ophthalmology Center the Second Affiliated HospitalZhejiang University School of MedicineHangzhou 310009Zhejiang ProvinceChina

AIM:To develop a deep learning-based model for automatic retinal vascular segmentation,analyzing and comparing parameters under diverse glucose metabolic status(normal,prediabetes,diabetes)and to assess the potential of artificial intelligence(AI)in image segmentation and retinal vascular parameters for predicting prediabetes and ***:Retinal fundus photos from 200 normal individuals,200 prediabetic patients,and 200 diabetic patients(600 eyes in total)were *** U-Net network served as the foundational architecture for retinal arteryvein *** automatic segmentation and evaluation system for retinal vascular parameters was trained,encompassing 26 ***:Significant differences were found in retinal vascular parameters across normal,prediabetes,and diabetes groups,including artery diameter(P=0.008),fractal dimension(P=0.000),vein curvature(P=0.003),C-zone artery branching vessel count(P=0.049),C-zone vein branching vessel count(P=0.041),artery branching angle(P=0.005),vein branching angle(P=0.001),artery angle asymmetry degree(P=0.003),vessel length density(P=0.000),and vessel area density(P=0.000),totaling 10 ***:The deep learning-based model facilitates retinal vascular parameter identification and quantification,revealing significant *** parameters exhibit potential as biomarkers for prediabetes and diabetes.

关键词： deep learning retinal vascular parameters segmentation model diabetes prediabetes

基于DSP的双输入BUCK变换器在LED驱动器中的应用

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电子科技大学学报 2014年第6期43卷 850-856页

作者：陈勇周俊电子科技大学能源科学与工程学院成都611731

提出一种将双输入Buck(TIBUCK)变换器应用于LED驱动器的方案,并详细分析该电路的性能特点。该TIBUCK变换器采用电压模式控制,由DSP作为控制核心,能够很好地调节输出电流,使LED工作在恒流状态。仿真和实验结果表明,TIBUCK变换器在降低开... 详细信息

提出一种将双输入Buck(TIBUCK)变换器应用于LED驱动器的方案,并详细分析该电路的性能特点。该TIBUCK变换器采用电压模式控制,由DSP作为控制核心,能够很好地调节输出电流,使LED工作在恒流状态。仿真和实验结果表明,TIBUCK变换器在降低开关管和二极管电压应力的同时实现了对输出电流的恒流控制,从而证明该变换器作为LED驱动器中的后级恒流部分是可行的。

关键词：恒流 DSP LED TIBUCK变换器

Experimental study on steam-water two-phase flow frictional pressure drops in helical coils

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Nuclear Science and Techniques 1997年第3期8卷 149-153页

作者： Bi Qin cheng, chen Ting Kuan, Tian yong Sheng, chen Xue Jun (National Laboratory of Multiphase Flow, Xi’an Jiaotong University, Xi’an710049)

ＥｘｐｅｒｉｍｅｎｔａｌｓｔｕｄｙｏｎｓｔｅａｍｗａｔｅｒｔｗｏｐｈａｓｅｆｌｏｗｆｒｉｃｔｉｏｎａｌｐｒｅｓｕｒｅｄｒｏｐｓｉｎｈｅｌｉｃａｌｃｏｉｌｓＢｉＱｉｎＣｈｅｎｇ，ＣｈｅｎＴｉｎｇＫｕａｎ，Ｔｉ... 详细信息

ＥｘｐｅｒｉｍｅｎｔａｌｓｔｕｄｙｏｎｓｔｅａｍｗａｔｅｒｔｗｏｐｈａｓｅｆｌｏｗｆｒｉｃｔｉｏｎａｌｐｒｅｓｕｒｅｄｒｏｐｓｉｎｈｅｌｉｃａｌｃｏｉｌｓＢｉＱｉｎＣｈｅｎｇ，ＣｈｅｎＴｉｎｇＫｕａｎ，ＴｉａｎＹｏｎｇＳｈｅｎｇ，Ｃｈｅｎ...

关键词：汽-水二相流部分压强螺形线圈中水滴

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全息制作不同晶面取向光子晶体模板

物理学报 2006年第2期55卷 688-691页

作者：钟永春朱少安汪河洲曾兆华陈用烈中山大学超快速激光光谱学国家重点实验室广州510275 中山大学高分子研究所广州510275

用单向光入射和单次曝光的激光全息技术制作了类金刚石结构,此类金刚石结构有宽完全带隙和低介质折射率要求等优点.在同一种光束配置下,引入恰当的匹配棱镜,用激光全息技术制作了大面积的类金刚石光学晶格不同晶面取向的亚微米周期结构... 详细信息

用单向光入射和单次曝光的激光全息技术制作了类金刚石结构,此类金刚石结构有宽完全带隙和低介质折射率要求等优点.在同一种光束配置下,引入恰当的匹配棱镜,用激光全息技术制作了大面积的类金刚石光学晶格不同晶面取向的亚微米周期结构.满足如负折射效应等研究中所需的特殊晶面取向要求.

关键词：激光全息技术光学晶格光子晶体

User-perceived e-mail service QoS parameters and measurement

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The Journal of China Universities of Posts and Telecommunications 2010年第3期17卷 85-90页

作者： LI yong-zhi , LIU Feng, LEI Zhen-ming, chen Ling School of Information and Communication Engineering, Beijing University of Posts and Telecommunications, Beijing 100876, China School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

A group of quality of service （QoS） parameters of electronic mail （e-mail） traffic are proposed from users＇ perspective. These parameters cover three fields： delay, throughput and usability. Concept and algorithm of each parameter are presented and its effect on user perceptions is described. In order to evaluate the effectiveness of these parameters, an active measurement system is implemented. Measured results show that the group of QoS parameters we proposed can be used to get a comprehensive view of user-perceived e-mail service QoS.

关键词： user perceptions e-mail service QoS active measurement

Supramolecular systems for bioapplications:recent research progress in China

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Science China Chemistry 2024年第5期67卷 1397-1441页

作者： Yue-Yang Liu Xiao-yong Yu Yu-chen Pan Hang Yin Shuang Chao Yujie Li He Ma Minzan Zuo Kun-Xu Teng Jun-Li Hou yong chen Dong-Sheng Guo Ruibing Wang Yuxin Pei Zhichao Pei Jiang-Fei Xu Xiao-Yu Hu Chunju Li Qing-Zheng Yang Leyong Wang Yu Liu Zhan-Ting Li State Key Laboratory of Organometallic Chemistry Key Laboratory of Synthetic and Self-Assembly Chemistry for Organic Functional MoleculesShanghai Institute of Organic ChemistryChinese Academy of SciencesUniversity of Chinese Academy of SciencesShanghai 200032China Department of Chemistry Fudan UniversityShanghai 200438China College of Chemistry State Key Laboratory of Elemento-Organic ChemistryCollaborative Innovation Center of Chemical Science and EngineeringNankai UniversityTianjin 300071China State Key Laboratory of Quality Research in Chinese Medicine Institute of Chinese Medical SciencesUniversity of MacaoMacao 999078China College of Chemistry&Pharmacy Northwest A&F UniversityYangling 712100China Key Lab of Organic Optoelectronics&Molecular Engineering Department of ChemistryTsinghua UniversityBeijing 100084China College of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 211106China Key Laboratory of Radiopharmaceuticals Ministry of EducationCollege of ChemistryBeijing Normal UniversityBeijing 100875China Tianjin Key Laboratory of Structure and Performance for Functional Molecules College of ChemistryTianjin Normal UniversityTianjin 300387China State Key Laboratory of Analytical Chemistry for Life Science Jiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China

Supramolecular systems feature dynamic,reversible and stimuli-responsive characteristics,which are not easily achieved by molecular *** last decade has witnessed tremendous advances in the investigations of supramolecular systems for various bioapplications,which include drug delivery,anticancer therapy,antibacterial therapy,photodynamic therapy,photothermal therapy,combination therapy,antidotes for residual drugs or toxins,and bioimaging and ***-guest chemistry has played a key role in the development of such bioactive supramolecular systems,and natural macrocycles(such as cyclodextrins),synthetic macrocycles(such as calixarenes,cucurbit[n]urils,and pillararenes),and porous framework polymers(such as supramolecular organic frameworks and flexible organic frameworks)have been most successfully used as hosts to build different kinds of host-guest systems for attaining designed *** self-assembly of rationally designed amphiphilic molecules,macromolecules and polymers represent another important approach for the construction of supramolecular architectures with advanced *** this review,we summarize the important contributions made by Chinese researchers in this field,with emphasis on those reported in the past five years.

关键词： host-guest chemistry drug delivery anticancer and antibacterial photodynamic therapy photothermal therapy antidote transmembrane channel bioimaging and biosensing