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基于板式GFRP剪力连接件的预制混凝土三明治板的组合度研究

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建筑结构学报 2015年第S2期36卷 188-195页

作者：黄俊旗戴建国香港理工大学土木与环境工程系香港红磡999077

通过基于板式GFRP剪力连接件的预制混凝土三明治板试件的静力受弯试验,进行了刚度及承载力组合度的计算,并基于通用有限元软件ANSYS建立试件的三维有限元力学模型,对其受力全过程进行了数值模拟。在验证了有限元分析模型准确性的基础上... 详细信息

通过基于板式GFRP剪力连接件的预制混凝土三明治板试件的静力受弯试验,进行了刚度及承载力组合度的计算,并基于通用有限元软件ANSYS建立试件的三维有限元力学模型,对其受力全过程进行了数值模拟。在验证了有限元分析模型准确性的基础上,对预制混凝土三明治板在不同板式GFRP连接件布置方式、材料性能、几何尺寸的整体刚度进行了分析,并将之与完全组合板刚度的理论值进行了对比(两者比值定义为刚度组合度)。分析结果表明:随剪跨段板式GFRP剪力连接件的抗剪刚度的提高,预制混凝土三明治板的刚度组合度呈非线性增长趋势,但其增长幅度逐渐变缓;随着保温层厚度的增加,刚度组合度有较大幅度的降低,但随着剪力连接件厚度的增加,刚度组合度对保温层厚度的敏感性下降。有限元分析结果亦表明:板式GFRP连接件对三明治板承载力组合度的影响没有对刚度组合度的影响显著;按照现有的板式GFRP剪力连接件设计方法很难达到完全组合的效果,在设计中应充分考虑对刚度的折减。

关键词：预制混凝土三明治板 GFRP剪力连接件有限元分析刚度组合度承载力组合度

A Comprehensive Investigation on Shear Performance of Improved Perfobond Connector

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Structural Durability & Health Monitoring 2024年第3期18卷 299-320页

作者： Caiping huang Zihan huang Wenfeng You School of Civil Engineering Architecture and EnvironmentHubei University of TechnologyWuhan430068China

This paper presents an easily installed improved perfobond connector (PBL) designed to reduce the shearconcentration of PBL. The improvement of PBL lies in changing the straight penetrating rebar to the Z-typepenetrating rebar. To study the shear performance of improved PBL, two PBL test specimens which containstraight penetrating rebar and six improved PBL test specimens which contain Z-type penetrating rebars weredesigned and fabricated, and push-out tests of these eight test specimens were carried out to investigate andcompare the shear behavior of PBL. Additionally, Finite Element Analysis (FEA) models of the PBL specimenswere established and validated against the test results. Through FEA, the effects of concrete grade, perforatedplate’s aperture, Z-type penetrating rebar’s diameter, Z-type penetrating rebar’s bending angle, and bending lengthon shear behaviors were discussed. The results indicate that (1) Compared with PBL specimens with straightpenetrating rebars, Z-type penetrating rebar can significantly improve the shear resistance and shear stiffnessof the specimens. This enhanced performance can be mainly attributed to the increased adhesion of the transverserebar. (2) By comparing the load-slip curve, the slip of PBL test specimens which contain straight penetratingrebar increases rapidly and the bearing capacity decreases rapidly after concrete craking, while the bearingcapacity of Z-type penetrating rebar specimens decreases first and then increases gradually, showing betterductility. (3) The stress of the PBL shear connector with Z-type penetrating rebar is more uniform than thePBL shear connector with straight penetrating rebar, and the overall deformation is more uniform. (4) The higherthe concrete grade, the higher the shear bearing capacity and the better ductility of the new PBL. Increasing theaperture of the perforated plate or the diameter of the rebar has a very limited effect on the improvement of theshear capacity of PBL. Through the system

关键词： PBL penetrating rebar push-out test load-slip curve shear capacity finite element analysis

Readily prepared and processed multifunctional MXene nanocomposite hydrogels for smart electronics

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SmartMat 2024年第2期5卷 103-114页

作者： Jiahui huang Xianwu huang Peiyi Wu State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Chemistry and Chemical EngineeringCenter for Advanced Low-Dimension MaterialsDonghua UniversityShanghaiChina State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular Science and Laboratory of Advanced MaterialsFudan UniversityShanghaiChina

Booming sophisticated robotics and prosthetics put forward high requirements on soft conductive materials that can bridge electronics and biology,those soft conductive materials should imitate the mechanical properties of biological tissues and build information transmission *** now,it remains a great challenge to handle the trade-off among ease of preparation,high conductivity,processability,mechanical adaptability,and external stimuli ***,a kind of readily prepared and processed multifunctional MXene nanocomposite hydrogel is reported,which is prepared via the fast gelation of cationic monomer initiated by delaminated MXene *** gelation time can be adjusted(several seconds to minutes)based on the MXene *** adjusting the MXene ratio,the resulting nanocomposites are ultrastretchable(>5000%),three-dimensional(3D)printable,and show outstanding mechanical and electrical *** expected,the integration of multifunctional systems onto various substrates(e.g.,gloves and masks)is further demonstrated via 3D printing and could achieve diverse sensory capabilities toward strain,pressure,and temperature,showing great prospects as smart flexible electronics.

关键词： 3D printable electronics MXene polymeric hydrogels stretchable and conductive

Reduced-Order Observer-Based LQR Controller Design for Rotary Inverted Pendulum

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 305-323页

作者： Guogang Gao LeiXu Tianpeng huang Xuliang Zhao Lihua huang College of Engineering China University of Petroleum-Beijing at KaramayKaramay834000China School of Electrical Engineering and Information Southwest Petroleum UniversityChengdu610500China

The Rotary Inverted Pendulum(RIP)is a widely used underactuated mechanical system in various applications such as bipedal robots and skyscraper stabilization where attitude control presents a significant *** the implementation of various control strategies to maintain equilibrium,optimally tuning control gains to effectively mitigate uncertain nonlinearities in system dynamics remains *** methods frequently rely on extensive experimental data or the designer’s expertise,presenting a notable *** paper proposes a novel tracking control approach for RIP,utilizing a Linear Quadratic Regulator(LQR)in combination with a reduced-order ***,the RIP system is mathematically modeled using the Newton-Euler-Lagrange ***,a composite controller is devised that integrates an LQR for generating nominal control signals and a reduced-order observer for reconstructing unmeasured *** approach enhances the controller’s robustness by eliminating differential terms from the observer,thereby attenuating unknown *** numerical simulations and experimental evaluations demonstrate the system’s capability to maintain balance below50Hz and achieve precise tracking below1.4 rad,validating the effectiveness of the proposed control scheme.

关键词： Rotary inverted pendulum(RIP) linear quadratic regulator(LQR) reduced-order observer states estimate

Challenges and Opportunities of Sub-6 GHz Integrated Sensing and Communications for 5G-Advanced and Beyond

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Chinese Journal of Electronics 2024年第2期33卷 323-325页

作者： Yuhong huang China Mobile Research Institute China Mobile Communications Group Co. Ltd

The integrated sensing and communications(ISAC) technology has been perceived as a key feature of5G-Advanced and beyond mobile communication networks. Compared with sensing in millimeter-wave bands, sensing at sub-6 GHz band is an exceptional incentive to promote the industrialization process of ISAC due to its incomparable advantages in industrial development, especially for intelligent transportation and smart drone networks. This paper elaborates on the top challenges of sub-6 GHz ISAC technologies, as well as the potential solutions to improve the sensing capability.

关键词： Electric potential Millimeter wave technology Transportation Mobile communication Sensors Millimeter wave communication Drones

Machine learning-assisted sparse observation assimilation for real-time aerodynamic field perception

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Science China(Technological Sciences) 2024年第5期67卷 1458-1469页

作者： ZHAO QingYu huang Jun GUO YuXin PAN YuXuan JI JingJing huang YongAn State Key Laboratory of Intelligent Manufacturing Equipment and Technology School of Mechanical Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China

Accurate aerodynamic distribution perception and real-time flight state evaluation are crucial for flight safety,e.g.,stall ***,the observations are usually sparse due to limitations in sensor mounting space and cost,and a reconstruction technology is urgently ***,a machine learning-assisted assimilation method based on sparse observations has been *** from the traditional reconstruction methods focusing on boundary condition correction,the proposed method formulates the flow field pressure distribution as a linear superposition of flow field modes,thereby forming a real-time reconstruction pattern that combines offline modal extraction using computational fluid dynamics(CFD)with real-time determination of modal weights using a neural *** this study,CFD simulations were conducted under 800different operating conditions for common modal extraction and model *** weights of these modes were determined online based on merely five observations for reconstructing the full pressure field.A pressure reconstruction with a relative error of 6.1%and a mean square error of 0.003 was achieved within the prescribed condition *** computational cost was just2 ms for each reconstruction run,significantly faster than the 20 min required by the classical reconstruction ensemble transform Kalman *** also showed that the method maintains almost the same accuracy amidst 1.5%measurement *** practical examples,shock waves and the change of lift coefficient were analyzed using the proposed method,providing remarkable evidence for the capability of the method in supporting stall *** validate the method’s effectiveness and explore its potential in real-time and accurate monitoring of an aircraft.

关键词： aerodynamic force sparse observation neural networks pressure field reconstruction

Imprints of ultralight axions on the gravitational wave and pulsar timing measurement

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Science China(Physics,Mechanics & Astronomy) 2024年第1期67卷 23-29页

作者： Ning Xie Fa Peng huang MOE Key Laboratory of TianQin Mission TianQin Research Center for Gravitational Physics&School of Physics and AstronomyFrontiers Science Center for TianQinGravitational Wave Research Center of CNSASun Yat-sen University(Zhuhai Campus)Zhuhai 519082China

The axion or axion-like particle motivated from a natural solution of strong CP problem or string theory is a promising dark matter *** study the new observational effects of ultralight axion-like particles by the space-borne gravitational wave detector and the radio *** the neutron star-black hole binary as an example,we demonstrate that the gravitational waveform could be obviously modified by the slow depletion of the axion cloud around the black hole formed through the superradiance *** compare these new effects on the binary with the well-studied effects from dynamical friction with dark matter and dipole radiation in model-independent ***,we discuss the constraints from LIGO/Virgo and study the detectability of the ultralight axion particles at LISA and TianQin.

关键词： gravitational wave axion dark matter

Associations of daily sedentary behavior,physical activity,and sleep with irritable bowel syndrome:A prospective analysis of 362,193 participants

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Journal of Sport and Health Science 2024年第1期13卷 72-80页

作者： Xu Gao Sifan Tian Ninghao huang Gang Sun Tao huang Department of Occupational and Environmental Health Sciences School of Public HealthPeking UniversityBeijing 100191China Department of Epidemiology and Biostatistics School of Public HealthPeking UniversityBeijing 100191China Department of Gastroenterology and Hepatology First Medical Center of People's Liberation Army General HospitalBeijing 100853China

Background:Irritable bowel syndrome(IBS)substantially affects quality of life and requires early *** study aimed to elucidate the relationships between IBS and daily behaviors,including sedentary behavior(SB),physical activity(PA),and *** particular,it seeks to identify healthy behaviors to reduce IBS risk,which previous studies have rarely ***:Daily behaviors were retrieved from self-reported data of 362,193 eligible UK Biobank *** cases were determined by self-report or health care data according to RomeⅣ***:A total of 345,388 participants were IBS-free at baseline,during a median follow-up of 8.45 years,19,885 incident IBS cases were *** examined individually,SB and shorter(≤7 h/day)or longer(>7 h/day)sleep duration were each positively associated with increased IBS risk,and PA was associated with lower IBS *** isotemporal substitution model suggested that replacing SB with other activities could provide further protective effects against IBS *** people sleeping≤7 h/day,replacing 1 h of SB with equivalent light PA,vigorous PA,or sleep was associated with 8.1%(95%confidence interval(95%CI):0.901-0.937),5.8%(95%CI:0.896-0.991),and 9.2%(95%CI:0.885-0.932)reduced IBS risk,*** people sleeping>7 h/day,light and vigorous PA were associated with a 4.8%(95%CI:0.926-0.978)and a 12.0%(95%CI:0.815-0.949)lower IBS risk,*** benefits were mostly independent of genetic risk for ***:SB and unhealthy sleep duration are risk factors for IBS.A promising way to mitigate IBS risk for individuals sleeping≤7 h/day and for those sleeping>7 h/day appears to be by replacing SB with adequate sleep or vigorous PA,respectively,regardless of the genetic predisposition of IBS.

关键词： Irritable bowel syndrome Isotemporal substitution model Physical activity Sedentary behavior Sleep

In situ direct reprogramming of astrocytes to neurons via polypyrimidine tract-binding protein 1 knockdown in a mouse model of ischemic stroke

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Neural Regeneration Research 2024年第10期19卷 2240-2248页

作者： Meng Yuan Yao Tang Tianwen huang Lining Ke En huang Key Laboratory of Brain Aging and Neurodegenerative Diseases of Fujian Province Fujian Medical UniversityFuzhouFujian ProvinceChina Department of Human Anatomy School of Basic Medical SciencesFujian Medical UniversityFuzhouFujian ProvinceChina Scientific Research Center School of Basic Medical SciencesFujian Medical UniversityFuzhouFujian ProvinceChina Department of Neurology Fujian Medical University Union HospitalFuzhouFujian ProvinceChina Fujian Key Laboratory of Vascular Aging Fujian Medical UniversityFuzhouFujian ProvinceChina

In situ direct reprogramming technology can directly convert endogenous glial cells into functional neurons in vivo for central nervous system repair. Polypyrimidine tract-binding protein 1(PTB) knockdown has been shown to reprogram astrocytes to functional neurons in situ. In this study, we used AAV-PHP.e B-GFAP-sh PTB to knockdown PTB in a mouse model of ischemic stroke induced by endothelin-1, and investigated the effects of GFAP-sh PTB-mediated direct reprogramming to neurons. Our results showed that in the mouse model of ischemic stroke, PTB knockdown effectively reprogrammed GFAP-positive cells to neurons in ischemic foci, restored neural tissue structure, reduced inflammatory response, and improved behavioral function. These findings validate the effectiveness of in situ transdifferentiation of astrocytes, and suggest that the approach may be a promising strategy for stroke treatment.

关键词： astrocyte in situ direct reprogramming ischemic stroke miR-30 based shRNA neuron polypyrimidine tract-binding protein 1 transdifferentiation