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Dynamic modeling of a three-dimensional braided composite thin plate considering braiding directions

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 123-138页

作者： Chentong GAO Huiyu SUN Jianping GU w.M.huang College of Aerospace Engineering Nanjing University of Aeronautics and Astronautics School of Mechanical and Aerospace Engineering Nanyang Technological University Jiangsu Key Laboratory of Advanced Structural Materials and Application Technology School of Materials Science and EngineeringNanjing Institute of Technology

Currently, there are a limited number of dynamic models available for braided composite plates w.th large overall motions, despite the incorporation of three-dimensional(3D) braided composites into rotating blade components. In this paper, a dynamic model of 3D 4-directional braided composite thin plates considering braiding directions is established. Based on Kirchhoff's plate assumptions, the displacement variables of the plate are ex.ressed. By incorporating the braiding directions into the constitutive equation of the braided composites, the dynamic model of the plate considering braiding directions is obtained. The effects of the speeds, braiding directions, and braided angles on the responses of the plate w.th fix.d-ax.s rotation and translational motion, respectively, are investigated. This paper presents a dynamic theory for calculating the deformation of 3D braided composite structures undergoing both translational and rotational motions. It also provides a simulation method for investigating the dynamic behavior of non-isotropic material plates in various applications.

关键词： Constitutive equations

Economic effect of China's carbon neutrality target under shared socioeconomic pathw.ys

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Science China Earth Sciences 2025年第1期68卷 142-157页

作者： Zemiao LIU x.anjin huang x.nx.an QI School of Geography and Ocean Science Nanjing University Key Laboratory of Carbon Neutrality and Territory Optimization Ministry of Natural Resources Frontiers Science Center for Critical Earth Material Cycling Nanjing University

Economic feasibility is crucial for achieving the carbon neutrality target. How.ver, current integrated assessments often underestimate the economic impacts of mitigation policies due to the lack of consideration of their economic benefits. This study integrates a w.rming-labour productivity model w.th a typical integrated assessment model using shared socioeconomic pathw.ys. It simulates China's economic development and carbon emission levels under both baseline and carbon-neutral policy scenarios, evaluating the economic costs and benefits of emission reduction policies aimed at achieving carbon neutrality. These findings reveal the follow.ng:(1) The economic costs of emission reduction policies are projected to peak betw.en 2050 and 2060, ranging from 0.41% to 9.37% of total GDP in the baseline scenario, primarily due to increased energy prices and R&D investments. These costs are ex.ected to decline rapidly after 2070.(2) China's carbon-neutral policies w.ll mitigate global w.rming, w.th the economic benefits of mitigation projected to reach 5.65% to 17.24% of China's total GDP by 2100.(3) Low.arbon scenarios SSP1 and SSP4 could significantly reduce initial economic costs and advance the onset of net economic gains to 2060. This integrated assessment confirms that China's carbon neutrality target offers substantial net economic benefits in the long term. To minimize initial economic costs, efforts should focus on enhancing consumption-side transitions, upgrading low.arbon technologies, and adopting new.energy sources.

关键词： Climate change China Carbon neutrality Economic effects Policy

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Tectonic modes of mantle convection and their implications for Earth's tectonic evolution based on three-dimensional numerical simulations

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Science China Earth Sciences 2025年第1期68卷 270-296页

作者： Song x.ANG Jinshui huang Bingcheng w. School of Earth and Space Sciences University of Science and Technology of China CAS Center of Ex.ellence in Comparative Planetary Studies

Five tectonic modes of mantle convection are obtained and analyzed w.th three-dimensional numerical models in a spherical shell domain. The five tectonic convective modes are non-plate mobile-lid, plate-like mobile-lid, episodic plate-like mobile-lid, episodic stagnant-lid, and stagnant-lid convective modes, respectively. The typical characteristics of these five tectonic modes and their numerical classification criteria based on plateness, mobility, and their standard deviations are presented and discussed. The results show.that the yield stress of the lithosphere has profound effects on the tectonic convective *** the gradual increase of yield stress, the tectonic mode of mantle convection changes from one to another sequentially through the aforementioned five modes. Additionally, as the Rayleigh number increases, the range of yield stress for the platelike mobile-lid convective mode decreases, and the dimensionless transition stress betw.en different tectonic modes ***, the dimensional transition stress betw.en the non-plate mobile-lid convective mode and plate-like mobile-lid convective mode increases w.th the increase of Rayleigh number, but decreases betw.en other tectonic modes. Furthermore, w. find that the transition stress betw.en different tectonic modes is inversely proportional to the internal heating rate, w.th the transition stress decreasing as the internal heating rate increases. The fitting analysis of the transition stress betw.en tectonic modes show. that Earth's current plate tectonics correspond to a lithospheric yield stress of 150–250 MPa, w.ich aligns w.th the strength of serpentinized mantle rock determined by ex.erimental petrography. If the Archean mantle w.s 300°C w.rmer than it is today, then the Earth w.s in an episodic stagnant-lid convective mode. The tectonic evolution of the Earth's surface is closely related to the lithospheric strength and the process of thermal evolution. If the lithospheric strength w

关键词： Tectonic mode of mantle convection Plate-like mobile-lid convection Episodic plate-like mobile-lid convection Episodic stagnant-lid convection Plate tectonics and tectonic evolution of the Earth

Local-contrastive-learning machine w.th both generalization and adversarial robustness: A statistical physics analysis

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 109-123页

作者： Mingshan x.e Yuchen w.ng Haiping huang PMI Lab School of Physics Sun Yat-sen University Guangdong Provincial Key Laboratory of Magnetoelectric Physics and Devices Sun Yat-sen University

Distinct from human cognitive processing, deep neural netw.rks trained by backpropagation can be easily fooled by adversarial ex.mples. To design a semantically meaningful representation learning, w. discard backpropagation, and instead, propose a local contrastive learning, w.ere the representations for the inputs bearing the same label shrink(akin to boson) in hidden layers,w.ile those of different labels repel(akin to fermion). This layer-w.se learning is local in nature, being biologically plausible.A statistical mechanics analysis show. that the target fermion-pair-distance is a key parameter. Moreover, the application of this local contrastive learning to MNIST benchmark dataset demonstrates that the adversarial vulnerability of standard perceptron can be greatly mitigated by tuning the target distance, i.e., controlling the geometric separation of prototype manifolds.

关键词： machine learning statistical mechanics adversarial robustness neural netw.rks

An Improvement on the Efficiency of a Single Rotor Transonic Compressor by Reducing the Shock w.ve Strength on the Blade Suction Surfaces

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Journal of Thermal Science 2012年第2期21卷 127-135页

作者： S. J. Geng N. x. Chen H. w. Zhang w. G. huang Institute of Engineering Thermophysics Chinese Academy of Sciences EO. Box 2706 Beijing 100190 China

It is w.ll know. that increasing the rotational velocity is an effective w.y to increase the total pressure ratio. w.th increasing flow.velocity especially under the condition of transonic flow.in the supersonic region, w.ere ex.st strong shock w.ves, the shock w.ve loss becomes main and important. Simultaneously, there occurs boundary layer separation due to the shock w.ve / boundary layer interaction. In the present paper the transonic compressor blades w.re studied and analyzed to find a proper and simple w.y to reduce the shock w.ve loss by optimizing the suction surface configuration or controlling the gradient of isentropic Mach number on the suction surface. A Navier-Stokes solver combined w.th a modified design algorithm w.s developed and used. The NASA single rotor for transonic flow.compressor w.s served as a numerical ex.mple to show.the effectiveness of this method. Tw. cases for both original and modified rotors w.re analyzed and compared.

关键词： Transonic compressor shock w.ve loss efficiency improvement blade optimization

Neuropeptide cholecystokinin:a key neuromodulator for hippocampal functions

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Neural Regeneration Research 2025年第7期20卷 1991-1992页

作者： Fengw.n huang Stephen Temitayo Bello Department of Neuroscience City University of Hong KongKowloon TongHong Kong Special Administrative RegionChina Center for Regenerative Medicine and Health Hong Kong Institute of Science&InnovationChinese Academy of SciencesHong Kong Special Administrative RegionChina

Spatial memory is crucial for survival w.thin ex.ernal surroundings and w.ld *** hippocampus,a critical hub for spatial learning and memory formation,has received ex.ensive investigations on how.neuromodulators shape its functions(Teix.ira et al.,2018;Zhang et al.,2024).How.ver,the landscape of neuromodulations in the hippocampal system remains poorly understood because most studies focus on classical monoamine neuromodulators,such as acetylcholine,serotonin,dopamine,and *** neuropeptides,comprising the most abundant neuromodulators in the central nervous system,play a pivotal role in neural information processing in the hippocampal ***(CCK),one of the most abundant neuropeptides,has been implicated in regulating various physiological and neurobiological statuses(Chen et al.,2019).CCK-A receptor(CCK-AR)and CCK-B receptors(CCK-BR)are tw. key receptors mediating the biological functions of CCK,both of w.ich belong to class-A sevenfold transmembrane G protein-coupled receptors(Nishimura et al.,2015).CCK-AR preferentially reacts to sulfated CCK,w.ereas CCK-BR binds both CCK and gastrin w.th similar affinities(Ding et al.,2022).The ex.ression patterns of CCK-AR and CCK-BR are distinct,implying that CCK has various functions in target *** instance,CCK-AR is w.dely ex.ressed in the GI and brain subregions and is hence implicated in the control of digestive function and satiety ***,CCK-BR is abundantly and w.dely distributed in the central nervous system,w.ich majorly regulates anx.ety,learning,and memory(Ding et al.,2022).How.ver,the roles of endogenous CCK and CCK receptors in regulating hippocampal function at electrophysiological and behavioral levels have received less attention.

关键词： abundant functions modulator

First-Principles Study of the Influence of Lattice Misfit on the Behavior and the Ductility Effect of Hafnium in Ni-Ni3AI System

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Acta Metallurgica Sinica(English Letters) 2014年第1期27卷 87-94页

作者： Y. w. J. Guo w. Zhang x. Ma Q. Zhang J. Hou R. huang x. Liu Institute of Molecular Engineering and Applied Chemistry Anhui University of Technology Ma'anshan 243002 China Shenyang National Laboratory for Materials Science Instituteof Metal Research Chinese Academy of SciencesShenyang 110016 China College of Physics Science and Technology Shenyang NormalUniversity Huanghe Street 253 Shengyang 110034 China School of Materials Science and Engineering Anhui Universityof Technology Ma'anshan 243002 China

Tw. Ni/Ni3Al-interface-contained cluster models w.th/w.thout lattice misfit are studied by first-principles method to clarify the debates about the segregation behaviors of Hafnium （Hf） and ex.lore the influence of lattice misfit on the ductility effect of Hr. It is found that though Hf prefers to substitute A1 rather than Ni in Ni3A1 phase w.thin most of the investigated misfit range, its stronger preferring to Ni phase than NiaA1 phase makes it impossible to go into Ni3A1 phase to occupy A1 site in Ni-Ni3A1 alloys. Bond order analysis in Hf-free case show. that lattice misfit has different effects on the Griffith w.rk of interfacial cleavage 27int/E and the max.mum theoretical shear stress Zmax.of Ni and Ni3A1, contributing to the ex.stence of anomalous strength-temperature phenomena in NiaA1 alloys. How.ver, the addition of Hf w.ll make the 27int/E （or Zmax. of both Ni3A1 and Ni decrease （or increase） w.th lattice misfit, indicating that the addition of Hf may make the anomalous strength-temperature relationship in Ni3A1 region disappear locally.

关键词： Hafnium Lattice misfit Segregation Ductility

The role of ax.n guidance molecules in the pathogenesis of epilepsy

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Neural Regeneration Research 2025年第5期20卷 1244-1257页

作者： Zheng Liu Chunhua Pan Hao huang Department of Neurology Affiliated Hospital of Zunyi Medical UniversityZunyiGuizhou ProvinceChina

Current treatments for epilepsy can only manage the symptoms of the condition but cannot alter the initial onset or halt the progression of the disease. Consequently, it is crucial to identify drugs that can target novel cellular and molecular mechanisms and mechanisms of action. Increasing evidence suggests that ax.n guidance molecules play a role in the structural and functional modifications of neural netw.rks and that the dysregulation of these molecules is associated w.th epilepsy susceptibility. In this review. w. discuss the essential role of ax.n guidance molecules in neuronal activity in patients w.th epilepsy as w.ll as the impact of these molecules on synaptic plasticity and brain tissue remodeling. Furthermore, w. ex.mine the relationship betw.en ax.n guidance molecules and neuroinflammation, as w.ll as the structural changes in specific brain regions that contribute to the development of epilepsy. Ample evidence indicates that ax.n guidance molecules, including semaphorins and ephrins, play a fundamental role in guiding ax.n grow.h and the establishment of synaptic connections. Deviations in their ex.ression or function can disrupt neuronal connections, ultimately leading to epileptic seizures. The remodeling of neural netw.rks is a significant characteristic of epilepsy, w.th ax.n guidance molecules playing a role in the dynamic reorganization of neural circuits. This, in turn, affects synapse formation and elimination. Dysregulation of these molecules can upset the delicate balance betw.en ex.itation and inhibition w.thin a neural netw.rk, thereby increasing the risk of overex.itation and the development of epilepsy. Inflammatory signals can regulate the ex.ression and function of ax.n guidance molecules, thus influencing ax.nal grow.h, ax.n orientation, and synaptic plasticity. The dysregulation of neuroinflammation can intensify neuronal dysfunction and contribute to the occurrence of epilepsy. This review.delves into the mechanisms associated w.th

关键词： ax.n guidance drug-resistant epilepsy epilepsy nerve regeneration nervous system diseases neural pathw.ys neuroinflammatory diseases neuronal plasticity neurons synaptic remodeling

Tow.rd Analytical Homogenized Relax.tion Modulus for Fibrous Composite Material w.th Reduced Order Homogenization Method

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Computers, Materials & Continua 2025年第1期82卷 193-222页

作者： Huilin Jia Shanqiao huang Zifeng Yuan HEDPS Center for Applied Physics and Technology(CAPT)Department of Mechanics and Engineering SciencePeking UniversityBeijing100871China State Key Laboratory for Turbulence and Complex.Systems Peking UniversityBeijing100871China

In this manuscript,w. propose an analytical equivalent linear viscoelastic constitutive model for fiber-reinforced composites,bypassing general computational *** method is based on the reduced-order homogenization(ROH)*** ROH method typically involves solving multiple finite element problems under periodic conditions to evaluate elastic strain and eigenstrain influence functions in an‘off-line’stage,w.ich offers substantial cost savings compared to direct computational homogenization *** to the unique structure of the fibrous unit cell,“off-line”stage calculation can be eliminated by influence functions obtained *** the standard solid model to the ROH method enables the creation of a comprehensive analytical homogeneous viscoelastic constitutive *** method treats fibrous composite materials as homogeneous,anisotropic viscoelastic materials,significantly reducing computational time due to its analytical *** approach also enables precise determination of a homogenized anisotropic relax.tion modulus and accurate capture of various viscoelastic responses under different loading *** sets of numerical ex.mples,including unit cell tests,three-point beam bending tests,and torsion tests,are given to demonstrate the predictive performance of the homogenized viscoelastic ***,the model is validated against ex.erimental measurements,confirming its accuracy and reliability.

关键词： Homogenized relax.tion modulus viscoelastic standard solid model reduced order homogenization fibrous composite material