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Frontiers of Structural and Civil Engineering 2023年第1期17卷 122-137页

作者： Junqi HUANG Qing JIANG Xun CHONG Xianguo YE Caihua LIU School of Civil and Hydraulic Engineering Hefei University of TechnologyHefei 230009China Anhui Civil Engineering Structures and Materials Laboratory Hefei 230009China

In this study,a novel diagonally inserted bar-type basalt fiber reinforced polymer(BFRP)connector was proposed,aiming to achieve both construction convenience and partially composite behavior in precast concrete sandwich panels(PCSPs).First,pull-out tests were conducted to evaluate the anchoring performance of the connector in concrete after exposure to different temperatures.Thereafter,direct shear tests were conducted to investigate the shear performance of the connector.After the test on the individual performance of the connector,five façade PCSP specimens with the bar-type BFRP connector were fabricated,and the out-of-plane flexural performance was tested under a uniformly distributed load.The investigating parameters included the panel length,opening condition,and boundary condition.The results obtained in this study primarily indicated that 1)the bar-type BFRP connector can achieve a reliable anchorage system in concrete;2)the bar-type BFRP connector can offer sufficient stiffness and capacity to achieve a partially composite PCSP;3)the boundary condition of the panel considerably influenced the out-of-plane flexural performance and composite action of the investigated façade PCSP.

关键词： precast concrete sandwich panel basalt fiber reinforced polymer pull-out performance shear performance out-of-plane flexural performance

Flexural behavior of high-strength,steel-reinforced,and prestressed concrete beams

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Frontiers of Structural and Civil Engineering 2021年第1期15卷 227-243页

作者： Qing JIANG Hanqin WANG Xun CHONG Yulong FENG Xianguo YE School of Civil and Hydraulic Engineering Hefei University of TechnologyHefei 230009China Anhui Key Laboratory of Civil Engineering and Materials Hefei 230009China College of Water Conservancy and Civil Engineering Xinjiang Agricultural UniversityUrumqi 830052China

To study the flexural behavior of prestressed concrete beams with high-strength steel reinforcement and high-strength concrete and improve the crack width calculation method for flexural components with such reinforcement and concrete,12 specimens were tested under static loading.The failure modes,flexural strength,ductility,and crack width of the specimens were analyzed.The results show that the failure mode of the test beams was similar to that of the beams with normal reinforced concrete.A brittle failure did not occur in the specimens.To further understand the working mechanism,the results of other experimental studies were collected and discussed.The results show that the normalized reinforcement ratio has a greater effect on the ductility than the concrete strength.The cracking-and peak-moment formulas in the code for the design of concrete(GB 50010-2010)applied to the beams were both found to be acceptable.However,the calculation results of the maximum crack width following GB 50010-2010 and EN 1992-1-1:2004 were considerably conservative.In the context of GB 50010-2010,a revised formula for the crack width is proposed with modifications to two major factors:the average crack spacing and an amplification coefficient of the maximum crack width to the average spacing.The mean value of the ratio of the maximum crack width among the 12 test results and the relative calculation results from the revised formula is 1.017,which is better than the calculation result from GB 50010-2010.Therefore,the new formula calculates the crack width more accurately in high-strength concrete and high-strength steel reinforcement members.Finally,finite element models were established using ADINA software and validated based on the test results.This study provides an important reference for the development of high-strength concrete and highstrength steel reinforcement structures.

关键词： high-strength steel reinforcement high-strength concrete flexural behavior crack width

Noise-Tolerant ZNN-Based Data-Driven Iterative Learning Control for Discrete Nonaffine Nonlinear MIMO Repetitive Systems

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IEEE/CAA Journal of Automatica Sinica 2024年第2期11卷 344-361页

作者： Yunfeng Hu chong Zhang Bo Wang Jing Zhao xun Gong Jinwu Gao Hong Chen State Key Laboratory of Automotive Simulation and Control Jilin UniversityJilin UniversityChangchun 130025China College of Communication Engineering Jilin UniversityJilin UniversityChangchun 130025China Department of Electromechanical Engineering University of MacaoMacao 999078China School of Artificial Intelligence Jilin UniversityChangchun 130012China IEEE College of Electronics and Information Engineering Tongji UniversityShanghai 200092China

Aiming at the tracking problem of a class of discrete nonaffine nonlinear multi-input multi-output(MIMO) repetitive systems subjected to separable and nonseparable disturbances, a novel data-driven iterative learning control(ILC) scheme based on the zeroing neural networks(ZNNs) is proposed. First, the equivalent dynamic linearization data model is obtained by means of dynamic linearization technology, which exists theoretically in the iteration domain. Then, the iterative extended state observer(IESO) is developed to estimate the disturbance and the coupling between systems, and the decoupled dynamic linearization model is obtained for the purpose of controller synthesis. To solve the zero-seeking tracking problem with inherent tolerance of noise,an ILC based on noise-tolerant modified ZNN is proposed. The strict assumptions imposed on the initialization conditions of each iteration in the existing ILC methods can be absolutely removed with our method. In addition, theoretical analysis indicates that the modified ZNN can converge to the exact solution of the zero-seeking tracking problem. Finally, a generalized example and an application-oriented example are presented to verify the effectiveness and superiority of the proposed process.

关键词： Adaptive control control system synthesis data-driven iterative learning control neurocontroller nonlinear discrete time systems

Fabry-Perot interference and piezo-phototronic effect enhanced flexible MoS_(2) photodetector

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Nano Research 2022年第5期15卷 4395-4402页

作者： Xuexia Chen xun Yang Qing Lou Yuan Zhang Yancheng Chen Yacong Lu Lin Dong chong-Xin Shan Henan Key Laboratory of Diamond Optoelectronic Materials and Devices Key Laboratory of Materials PhysicsMinistry of Educationand School of Physics and MicroelectronicsZhengzhou UniversityZhengzhou 450052China

Flexible photodetectors(PDs)are indispensable components for next-generation wearable electronics.Recently,two-dimensional(2D)materials have been implemented as functional flexible optoelectronic devices due to their characteristics of atomically thin layers,excellent flexibility,and strain sensitivity.In this work,we developed a flexible photodetector based on MoS_(2)/NiO heterojunction,and Fabry-Perot(F-P)and piezo-phototronic effect have been employed to enhance the responsivity(R)and external quantum efficiency(EQE)of the devices.The F-P effect is utilized to improve the optical absorption of the MoS_(2),resulting in an enhancement in the photoluminescence(PL)of monolayer MoS_(2) and the EQE of the photodetector by 30 and 130 times,respectively.The flexible photodetector exhibits an ultrahigh detectivity(D*)of 2.6×10^(14) Jones,which is the highest value ever reported for flexible MoS_(2) PDs.The piezo-potential of monolayer MoS_(2) decreases the valence band offset at the interface of MoS_(2)/NiO,which increases the transfer efficiency of the photon-generated carriers significantly.Under 1.17%tensile strain,the R of the flexible photodetector can be enhanced by 271%.This research may provide a universal strategy for the design and performance optimization of 2D materials heterostructures for flexible optoelectronics.

关键词： flexible photodetector MoS_(2) Fabry-Perot(F-P)interference piezo-phototronic effect

Ultrasensitive broadband position-sensitive detector based on graphitic carbon nitride

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Nano Research 2023年第1期16卷 1277-1285页

作者： Xuexia Chen xun Yang Qing Lou Yongzhi Tian Zhiyu Liu Chaofan Lv Yancheng Chen Lin Dong chong-Xin Shan Henan Key Laboratory of Diamond Optoelectronic Materials and Devices Key Laboratory of Material PhysicsMinistry of EducationSchool of Physics and MicroelectronicsZhengzhou UniversityZhengzhou 450052China

As a typical two-dimensional material,graphitic carbon nitride(g-CN)has attracted great interest because of its distinctive electronic,optical,and catalytic properties.However,the absence of a feasible route toward large-area and high-quality films hinders its development in optoelectronics.Herein,high-quality g-CN films have been grown on Si substrate via a vapor-phase transport-assisted condensation method.The g-CN/Si heterojunction shows an obvious response to ultraviolet–visible-near infrared photons with a responsivity of 133 A·W−1,which is two orders of magnitude higher than the best value ever reported for g-CN photodetectors.A position-sensitive detector(PSD)has been developed using the lateral photovoltaic effect of the g-CN/Si heterojunction.The PSD shows a wide response spectrum ranging from 300 to 1,100 nm,and a position sensitivity and rise/decay time of 395 mV·mm−1 and 3.1/50μs,respectively.Moreover,the application of the g-CN/Si heterojunction photodetector in trajectory tracking and acoustic detection has been realized for the first time.This work unveils the potential of g-CN for large-area photodetectors,and prospects for their applications in trajectory tracking and acoustic detection.

关键词： graphitic carbon nitride(g-CN) position-sensitive detector(PSD) lateral photovoltaic effect(LPE) heterojunction trajectory tracking acoustic detection

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劲性轮辐式张弦混合悬挂结构设计研究

建筑结构 2023年第15期53卷 6-13页

作者：孙逊张翀东南大学建筑设计研究院有限公司南京210096

劲性轮辐式张弦混合悬挂结构是一种新型的刚柔并济的结构体系,其结构系统主要由内外环梁、径向布置的钢拉梁及内外环双弦支系统组成。通过其在青岛市民健身中心体育馆结构中的应用,对该体系的传力途径及内力分布进行了分析研究;对内外... 详细信息

劲性轮辐式张弦混合悬挂结构是一种新型的刚柔并济的结构体系,其结构系统主要由内外环梁、径向布置的钢拉梁及内外环双弦支系统组成。通过其在青岛市民健身中心体育馆结构中的应用,对该体系的传力途径及内力分布进行了分析研究;对内外环双弦支系统进行了参数化分析;对结构在施工阶段的预应力张拉进行了模拟分析;采用拆除构件法验证了结构的抗连续倒塌能力;并对其抗震性能进行了研究。研究结果表明,该结构体系的受力机理与建筑内凹屋盖的造型有很好的结合,径向布置的钢拉梁作为拉弯构件将内凹屋盖的竖向荷载传递至外圈受压环梁,内外环双弦支系统有效地改善了屋盖的承载性能并减小了屋盖的竖向变形,整体结构在极端条件下具有良好的抗超载能力和抗连续倒塌能力。

关键词：劲性轮辐式张弦混合悬挂结构内外环双弦支系统参数化分析预应力张拉连续倒塌

In situ formed synaptic Zn@LiZn host derived from ZnO nanofiber decorated Zn foam for dendrite-free lithium metal anode

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Nano Research 2023年第6期16卷 8345-8353页

作者： Jian Bao Hai-Juan Pei Xin-Yang Yue xun-Lu Li Cui Ma Rui-Jie Luo chong-Yu Du Yong-Ning Zhou Department of Materials Science Fudan UniversityShanghai 200433China State Key Laboratory of Space Power-Sources Technology Shanghai Institute of Space Power-SourcesShanghai 200245China Department of Chemical Engineering Tsinghua UniversityBeijing 100084China

Lithium metal is regarded as the most promising anode material for next generation high energy density lithium batteries due to its high theoretical capacity and lowest potential versus standard hydrogen electrode.However,lithium dendrite growth and huge volume change during cycling hinder its practical application.It is of great importance to design advanced Li metal anodes to solve these problems.Herein,we report a ZnO-coated Zn foam as the host matrix to pre-store lithium through thermal infusing,achieving a Zn@ZnO foam supported Li composite electrode(LZO).Needlelike ZnO nanofibers grown on the Zn foam greatly increase the surface area and enhance the lithiophilicity of the Zn foam.In situ formed synaptic LiZn layer after lithium infusion can disperse local current density and lower Li diffusion barrier effectively,leading to homogeneous Li deposition behavior,thus suppressing dendrite formation.The porous Zn foam skeleton can accommodate volume variation of the electrode during longterm cycling.Benefiting from these merits,the LZO anode exhibits much better cycle stability and rate capability in both symmetrical and full cells with low voltage hysteresis than the bare Li anode.This work opens a new opportunity in designing high performance composite Li anode for lithium-metal batteries.

关键词： lithium batteries anode LiZn alloy thermal infusion Li metal

国际收支结构可维持性影响因素分析——基于金融资产竞争力的视角

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财经问题研究 2022年第9期 3-16页

作者：邱崇明曾珣厦门大学金融系福建厦门361005 招商局金融集团有限公司分析和知识管理中心广东深圳518000

一国经济遇到重大冲击时国际收支结构是否可维持,不仅关系到金融稳定,还关系到资本账户开放和货币国际化的进程会不会受挫。而国际收支结构可维持性在很大程度取决于该国对外输出金融资产的能力,即金融资产竞争力。本文基于家庭资产配... 详细信息

一国经济遇到重大冲击时国际收支结构是否可维持,不仅关系到金融稳定,还关系到资本账户开放和货币国际化的进程会不会受挫。而国际收支结构可维持性在很大程度取决于该国对外输出金融资产的能力,即金融资产竞争力。本文基于家庭资产配置的微观视角建立理论模型,寻找决定金融资产竞争力和影响金融资产国际贸易差额的深层因素,并采用跨国面板数据,利用广义最小二乘法估计在随机效应模型下资本成本和存贷利差对金融资产净输出的影响。研究结果表明,除反映资本丰歉度的资本成本等传统理论所揭示的因素外,由法律制度、社会信用环境和金融约束政策等因素决定的投资者保护水平也对金融资产净输出产生显著影响。因此,从完善法律制度、净化社会信用环境和退出金融约束政策等方面入手,切实有效地保护投资者利益,提升金融资产国际竞争力,对提高中国国际收支账户应对重大事件冲击能力,夯实资本账户开放和人民币国际化基础具有重要的现实意义。

关键词：国际收支结构金融资产竞争力资本账户开放投资者保护水平社会信用环境金融约束政策

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国际金融的“赫希曼效应”

世界经济与政治 2020年第6期 132-155,160页

作者：庞珣陈冲清华大学国际关系学系北京100084

2008年国际金融危机引发对全球治理体系的深入反思和创新尝试,加速了国际关系中的权力转移和结构变迁。中央银行间双边货币互换协定体系从危机中脱颖而出并迅速生长。中国以包容的态度和积极的行动一跃成为双边货币互换协定全球网络的中... 详细信息

2008年国际金融危机引发对全球治理体系的深入反思和创新尝试,加速了国际关系中的权力转移和结构变迁。中央银行间双边货币互换协定体系从危机中脱颖而出并迅速生长。中国以包容的态度和积极的行动一跃成为双边货币互换协定全球网络的中心,在国内外广泛引发有关国际金融纽带如何塑造国际关系的理论思考和政策探寻。聚焦于中国货币互换协定的国际政治影响,作者根据协定在相互依存和风险信息两个维度上的不对称性特质,重新审视关于国际经济关系会带来外交立场接近的“赫希曼效应”,强调互换协定的塑造性权力以及信号传递实践开启的认同塑造和互信构建进程。在理论分析的基础上,作者采用定量和定性相结合的方法进行实证探索。回归分析运用混合效应模型对191个国家在2009—2018年的数据进行假设检验,在普遍性上支持了中国货币互换协定会产生“赫希曼效应”。作者以阿根廷为案例进行的定性研究,使用合成控制法提高案例研究在比较分析上的客观性和因果分析上的严密性,追踪和解释了“赫希曼效应”在方向和程度上的动态变化。这些分析深化了关于经济相互依存如何塑造国家关系的理论思考,也有助于从国际关系视角来理解人民币国际化的政策、进程和影响。合成控制法将定量方法服务于质性研究,是一种富有前景的个案研究路径。

关键词：金融外交央行货币互换协定赫希曼效应合成控制法金融全球治理

非洲恐怖袭击时空规律的大数据分析——基于GIS技术和分离总体持续期模型

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外交评论（外交学院学报） 2020年第2期37卷 121-154,I0005页

作者：陈冲庞珣清华大学国际关系学系北京100084

大数据及其分析技术的发展极大地推动了国际关系研究的发展,使得传统国际关系研究无法完成的任务变为可能。恐怖主义是当今全球治理中重大而棘手的问题,也是国际关系领域长期关注的议题。本文运用海量事件数据和地理信息系统(GIS)技术,... 详细信息

大数据及其分析技术的发展极大地推动了国际关系研究的发展,使得传统国际关系研究无法完成的任务变为可能。恐怖主义是当今全球治理中重大而棘手的问题,也是国际关系领域长期关注的议题。本文运用海量事件数据和地理信息系统(GIS)技术,将恐怖袭击的地理单元细粒化到以0.5×0.5经纬度作为分辨率的时空网格,寻找微观分析单元上恐怖袭击的时空规律,并运用分离总体持续期模型对恐怖袭击风险的空间分布和发生时机进行解释和预测。通过对非洲10674个时空网格在1994-2013年间恐怖袭击的时空特征进行分析,本文对非洲恐怖袭击发生时机进行精准捕捉,对恐袭地点进行细粒化定位,并对恐袭地理分布进行"疫区"与"免疫区"区分,不但深化了对恐怖主义的认识,而且提高了恐袭预测的精度和实际应用价值。本文的研究尝试表明,在大数据时代进行国际关系研究,不仅要充分利用海量数据提供的前所未有的丰富信息,更要选择和运用恰当的统计技术对复杂时空相关性进行细粒度分析,从而形成有效的创新路径。

关键词：大数据恐怖主义非洲地理信息系统时空网格国际关系研究事件数据