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IEEE/cAA Journal of Automatica Sinica 2024年第3期11卷 649-660页

作者： Meilin li Yue long Tieshan li Hongjing liang c.l.Philip chen the School of Automation Engineering University of Electronic Science and Technology of ChinaChengdu 611731China IEEE the Yangtze Delta Region Institute University of Electronic Science and Technology of ChinaHuzhou 313000 the laboratory of Electromagnetic Space cognition and Intelligent control Beijing 100089China the School of computer Science and Engineering South China University of TechnologyGuangzhou 510006

This paper investigates the consensus control of multi-agent systems(MASs) with constrained input using the dynamic event-triggered mechanism(ETM).consider the MASs with small-scale networks where a centralized dynamic ETM with global information of the MASs is first ***,a distributed dynamic ETM which only uses local information is developed for the MASs with large-scale *** is shown that the semi-global consensus of the MASs can be achieved by the designed bounded control protocol where the Zeno phenomenon is eliminated by a designable minimum inter-event *** addition,it is easier to find a trade-off between the convergence rate and the minimum inter-event time by an adjustable ***,the results are extended to regional consensus of the MASs with the bounded control *** simulations show the effectiveness of the proposed approach.

关键词： constrained input designable minimum inter-event time directed communication topology dynamic event-triggered mechanism MASs consensus control

UNcONDITIONAl cONVERGENcE AND ERROR ESTIMATES OF A FUllY DIScRETE FINITE ElEMENT METHOD FOR THE MIcROPOlAR NAVIER-STOKES EQUATIONS

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Journal of computational Mathematics 2024年第1期42卷 71-110页

作者： Shipeng Mao Jiaao sun Wendong Xue NcMIS LSECInstitute of Computational Mathematics and Scientific/Enginnering ComputingAcademy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China

In this paper,we consider the initial-boundary value problem(IBVP)for the micropolar Naviers-Stokes equations(MNSE)and analyze a first order fully discrete mixed finite element *** first establish some regularity results for the solution of MNSE,which seem to be not available in the ***,we study a semi-implicit time-discrete scheme for the MNSE and prove l2-H1 error estimates for the time discrete ***,certain regularity results for the time discrete solution are establishes *** on these regularity results,we prove the unconditional l2-H1 error estimates for the finite element solution of ***,some numerical examples are carried out to demonstrate both accuracy and efficiency of the fully discrete finite element scheme.

关键词： Micropolar fluids Regularity estimates Euler semi-implicit scheme Mixed finite element methods Unconditional convergence

A Note on Gradient Estimates for Elliptic Equations with Discontinuous coefficients

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chinese Annals of Mathematics,Series B 2024年第1期45卷 1-10页

作者： Yu PENG Xiandong sun Huichun ZHANG Department of Mathematics Sun Yat-Sen UniversityGuangzhou 510275China.

The authors will use a method in metric geometry to show an l^(P)-estimate for gradient of the weak solutions to elliptic equations with discontinuous coefficients,even the BMO semi-norms of the coefficients are not *... 详细信息

关键词： l^(p)-Estimate Elliptic equation Discontinuous coefficients

Analysis of blocking slurry diffusion parameters for a new self-starting drainage anchor cable

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Journal of Earth Science 2024年

作者： WANG Xu GE Qi lü chengcheng SHU Junwei sun Hongyue Sino-Italy Ningbo Ecological Park Holding Group co. ltd Ocean college Zhejiang University college of civil Engineering and Architecture Zhejiang University School of civil Engineering Nanjing Forestry University

A new self-starting drainage anchor that combines prestressed anchor cables with self-starting drainage is proposed. The novelty of the self-starting drainage method is the realization of the drainage and anchoring in the one inclined borehole. Reduction in the number of boreholes can greatly decrease the construction cost and duration of the project. The adverse effect of drilling construction disturbance on the slope is reduced. To tackle the possible blockage of the drainage cavity due to slurry leakage during the solidification process after finishing grouting in the blocking section. To this end， a theoretical equation for the slurry diffusion radius under slurry self-weight pressure boundary conditions is deduced. The result is verified for precision through comparison with numerical simulation. The findings reveal that the permeability coefficient of rock and soil mass makes the most significant impact on the slurry diffusion radius， succeeded by the length of the grouting blocking section， slurry initial setting time， and drilling inclination in descending order of influence. With the 5% mass ratio of a "711" type slurry quick-setting agent， the maximum slurry diffusion radius can be reduced from 0.925m to 0.449m， a reduction of 0.476m， which is comparatively more recommended.

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Insights and implications of sexual dimorphism in osteoporosis

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Bone Research 2024年第1期12卷 20-49页

作者： Yuan-Yuan Zhang Na Xie Xiao-Dong sun Edouard c.Nice Yih-cherng liou canhua Huang Huili Zhu Zhisen Shen Key laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province Sichuan Research Center for Drug Precision Industrial TechnologyWest China School of PharmacySichuan UniversityChengdu 610041China West china School of Basic Medical Sciences&Forensic Medicine Sichuan UniversityChengdu 610041China Department of Biochemistry and Molecular Biology Monash UniversityClaytonVIC 3800Australia Department of Biological Sciences Faculty of ScienceNational University of SingaporeSingapore 117543Republic of Singapore Department of Biotherapy Cancer Center and State Key Laboratory of BiotherapyWest China Hospitaland West China School of Basic Medical Sciences&Forensic MedicineSichuan UniversityChengdu 610041China Key laboratory of Birth Defects and Related Diseases of Women and children of Ministry of Education Department of Reproductive MedicineWest China Second University Hospital of Sichuan UniversityChengduChina Department of Otorhinolaryngology and Head and Neck Surgery The Affiliated Lihuili HospitalNingbo University315040 NingboZhejiangChina

Osteoporosis,a metabolic bone disease characterized by low bone mineral density and deterioration of bone microarchitecture,has led to a high risk of fatal osteoporotic fractures *** evidence has revealed that sexual dimorphism is a notable feature of osteoporosis,with sex-specific differences in epidemiology and ***,females are more susceptible than males to osteoporosis,while males are more prone to disability or death from the *** date,sex chromosome abnormalities and steroid hormones have been proven to contribute greatly to sexual dimorphism in osteoporosis by regulating the functions of bone *** the sex-specific differences in osteoporosis and its related complications is essential for improving treatment strategies tailored to women and *** literature review focuses on the mechanisms underlying sexual dimorphism in osteoporosis,mainly in a population of aging patients,chronic glucocorticoid administration,and ***,we highlight the implications of sexual dimorphism for developing therapeutics and preventive strategies and screening approaches tailored to women and ***,the challenges in translating bench research to bedside treatments and future directions to overcome these obstacles will be discussed.

关键词： osteoporosis epidemiology overcome

A Methodology for Assessing Axial compressor Stability with Inlet Temperature Ramp Distortion

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Journal of Thermal Science 2024年第3期33卷 856-871页

作者： sun Dakun GU Benhao NING Fangfei FANG Yibo DONG Xu XU Dengke sun Xiaofeng School of Energy and Power Engineering Beihang UniversityBeijing102206China Research Institute of Aero-engine Beihang UniversityBeijing102206China

Based on a small perturbation stability model for periodic flow,the effects of inlet total temperature ramp distortion on the axial compressor are investigated and the compressor stability is quantitatively *** the beginning,a small perturbation stability model for the periodic flow in compressors is proposed,referring to the governing equations of the Harmonic Balance *** stability model is validated on a single-stage low-speed compressor TA36 with uniform inlet ***,the unsteady flow of TA36 with different inlet total temperature ramps and constant back pressure is simulated based on the Harmonic Balance *** on these simulations,the compressor stability is analyzed using the proposed small perturbation ***,the Dynamic Mode Decomposition method is employed to accurately extract pressure *** two parameters of the temperature ramp,ramp rate and Strouhal number,are discussed in this *** results indicate the occurrence and extension of hysteresis loops in the rows,and a decrease in compressor stability with increasing ramp *** performance is divided into two phases,stable and limit,based on the ramp ***,the model predictions suggest that a decrease in period length and an increase in Strouhal number lead to improved compressor *** DMD results imply that for compressors with inlet temperature ramp distortion,the increase of high-order modes and oscillations at the rotor tip is always the signal of decreasing stability.

关键词： axial compressor stability small perturbation model inlet temperature ramp distortion harmonic balance method dynamic mode decomposition method

Synthesis of multifunctional additives for solid propellants:Structure,properties and mechanism

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Defence Technology（防务技术） 2024年第3期33卷 308-316页

作者： Pingan Zhang lina sun Jianmin Yuan Jianru Deng college of chemistry and chemical Engineering Hunan UniversityChangsha 410082PR China college of Material Science and Engineering Hunan UniversityChangsha 410082PR China Hu Bei Sanjiang Aerospace Jianghe chemical Technology co. LtdYichang 444200PR China

To simplify the composite propellant formulation and address the current issue of the single-functionality present in existing additives,the multi-cyano,amine-based polybutadiene(AEHTPB-cN)was prepared based on AEHTPB by adopting appropriate synthesis *** replacing 10% of HTPB binder in the propellant formulation,it can effectively enhance the interfacial bond strength between the propellant binder matrix and solid fillers(AP(ammonium perchlorate)and RDX(cyclotrimethylene-trinitramine)),the mechanical properties of the HTPB/AP/RDX/Al propellant were superior to blank control propellant with an improvement of 35.4% in tensile strength,62.0% enhancement in elongation at break,and reduce the propellant burn rate by 10.7% with any energy *** function mechanism of AEHTPB-cN was systematically elucidated through experiments and computer simulation *** results show that the tertiary amine group in AEHTPB-cN can react with AP to form ammonium ionic bonds,and the hydroxyl and cyano groups can form hydrogen bonding interactions with AP,which enables AEHTPB-cN to be firmly adsorbed on the AP surface through chemical and physical *** RDX,the interfacial bonding effect of AEHTPB-cN is attributed to their ability to form c-H···N≡c weak hydrogen bonding interaction between the cyano group and RDX methylene group.

关键词： Hydroxyl-terminated polybutadiene(HTPB) HTPB propellant chemical modification Bonding agent Mechanism

Effect of structural characteristics on the transport characteristics of solid particles in the thermal storage and release system of circulating fluidized bed

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Particuology 2024年第6期89卷 22-31页

作者： Zengcai Ji Guoliang Song Zihua Tang liwei sun Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing100190China University of chinese Academy of Sciences Beijing100049China Dalian National laboratory for clean Energy Dalian116023China

coal-fired power generation stands as the most economically viable modulating power source in present-day *** holds the potential to offer prospective solutions to the challenges posed by the rapid expansion of intermittent,unpredictable,and unstable renewable energy *** particle thermal storage technology emerges as an effective means to enhance the flexibility of coal-fired circulating fluidized bed power *** attain an optimized structure for the solid particle thermal storage and release system in circulating fluidized bed units,experimental research was conducted on a 0.1 MWth circulating fluidized bed test *** study delved into the impact of ash storage bin geometries and the shapes of their feed-discharge valves on the control properties of solid particle *** experimental outcomes reveal that employing inverted m-shaped valve and dual U-shaped valves for feed control,alongside U-shaped valves and N-shaped valves for discharge control,both enable efficient and rapid storage and release of solid particles within the circulating fluidized *** similar air distribution conditions,the inverted m-shaped valve exhibits lower conveying energy consumption than the dual U-shaped valves,while the N-shaped valve excels in control characteristics over the U-shaped ***,the inverted m-shaped valve and the N-shaped valve demonstrate optimal overflow port heights,and the ash storage bin exhibits an optimum height-to-diameter ratio.

关键词： Solid particle Thermal storage System structure Transport regulation

Adaptive neural network control of a 2-DOF helicopter system considering input constraints and global prescribed performance

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Science china(Information Sciences) 2024年第7期67卷 224-239页

作者： Zhijia ZHAO Jiale WU Zhijie lIU We HE c.l.Philip cHEN School of Mechanical and Electrical Engineering Guangzhou University School of Intelligence Science and Technology and Key laboratory of Intelligent Bionic Unmanned Systems of Ministry of Education University of Science and Technology Beijing School of computer Science and Engineering South China University of Technology Pazhou lab

In this study, an adaptive neural network(NN) control is proposed for nonlinear two-degree-offreedom(2-DOF) helicopter systems considering the input constraints and global prescribed ***, radial basis function NN(RBFNN) is employed to estimate the unknown dynamics of the helicopter system. Second, a smooth nonaffine function is exploited to approximate and address nonlinear constraint functions. Subsequently, a new prescribed function is proposed, and an original constrained error is transformed into an equivalent unconstrained error using the error transformation and barrier function transformation methods. The analysis of the established lyapunov function proves that the controlled system is globally uniformly bounded. Finally, the simulation and experimental results on a constructed Quanser's test platform verify the rationality and feasibility of the proposed control.

关键词： adaptive NN control 2-DOF helicopter global prescribed performance input constraints

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Achieving Negatively charged Pt Single Atoms on Amorphous Ni(OH)_(2)Nanosheets with Promoted Hydrogen Absorption in Hydrogen Evolution

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Nano-Micro letters 2024年第10期16卷 213-224页

作者： Yue liu Gui liu Xiangyu chen chuang Xue Mingke sun Yifei liu Jianxin Kang Xiujuan sun lin Guo School of chemistry Beijing Advanced Innovation Center for Biomedical EngineeringKey Laboratory of Bio-inspired Smart Interfacial Science and TechnologyBeihang UniversityBeijing 100191People's Republic of China School of chemistry Key Laboratory of Environmentally Friendly Chemistry and Applications of Ministry of EducationXiangtan UniversityXiangtan 411105HunanPeople'Republic of China

Single-atom(SA)catalysts with nearly 100%atom utilization have been widely employed in electrolysis for decades,due to the outperforming catalytic activity and ***,most of the reported SA catalysts are fixed through the strong bonding between the dispersed single metallic atoms with nonmetallic atoms of the substrates,which greatly limits the controllable regulation of electrocatalytic activity of SA *** this work,Pt-Ni bonded Pt SA catalyst with adjustable electronic states was successfully constructed through a controllable electrochemical reduction on the coordination unsaturated amorphous Ni(OH)_(2)nanosheet *** on the X-ray absorption fine structure analysis and first-principles calculations,Pt SA was bonded with Ni sites of amorphous Ni(OH)_(2),rather than conventional O sites,resulting in negatively charged Pt^(δ-).In situ Raman spectroscopy revealed that the changed configuration and electronic states greatly enhanced absorbability for activated hydrogen atoms,which were the essential intermediate for alkaline hydrogen evolution *** hydrogen spillover process was revealed from amorphous Ni(OH)_(2)that effectively cleave the H-O-H bond of H_(2)O and produce H atom to the Pt SA sites,leading to a low overpotential of 48 mV in alkaline electrolyte at-1000 mA cm^(-2)mg^(-1)_(Pt),evidently better than commercial Pt/c *** work provided new strategy for the control-lable modulation of the local structure of SA catalysts and the systematic regulation of the electronic states.

关键词： Hydrogen evolution reaction Amorphous Pt single atoms Hydrogen spillover