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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 1039-1050页

作者： chi ma Dianbiao Dong the School of Mechanical Engineering Northwestern Polytechnical UniversityXi’an 710072China

This paper studies the problem of time-varying formation control with finite-time prescribed performance for nonstrict feedback second-order multi-agent systems with unmeasured states and unknown *** eliminate nonlinearities,neural networks are applied to approximate the inherent dynamics of the *** addition,due to the limitations of the actual working conditions,each follower agent can only obtain the locally measurable partial state information of the leader *** address this problem,a neural network state observer based on the leader state information is ***,a finite-time prescribed performance adaptive output feedback control strategy is proposed by restricting the sliding mode surface to a prescribed region,which ensures that the closed-loop system has practical finite-time stability and that formation errors of the multi-agent systems converge to the prescribed performance bound in finite ***,a numerical simulation is provided to demonstrate the practicality and effectiveness of the developed algorithm.

关键词： Finite-time control multi-agent systems neural network prescribed performance control time-varying formation control

maUN:Memory-Augmented Deep Unfolding Network for Hyperspectral Image Reconstruction

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1139-1150页

作者： Qian Hu Jiayi ma yuan Gao Junjun Jiang Yixuan yuan Electronic Information School Wuhan UniversityWuhan 430072China School of Computer Science and Technology Harbin Institute of TechnologyHarbin 150001China Department of Electronic Engineering Chinese University of Hong KongHong Kong 999077China

Spectral compressive imaging has emerged as a powerful technique to collect the 3D spectral information as 2D *** algorithm for restoring the original 3D hyperspectral images(HSIs)from compressive measurements is pivotal in the imaging *** approaches painstakingly designed networks to directly map compressive measurements to HSIs,resulting in the lack of interpretability without exploiting the imaging *** some recent works have introduced the deep unfolding framework for explainable reconstruction,the performance of these methods is still limited by the weak information transmission between iterative *** this paper,we propose a Memory-Augmented deep Unfolding Network,termed maUN,for explainable and accurate HSI ***,maUN implements a novel CNN scheme to facilitate a better extrapolation step of the fast iterative shrinkage-thresholding algorithm,introducing an extra momentum incorporation step for each iteration to alleviate the information ***,to exploit the high correlation of intermediate images from neighboring iterations,we customize a cross-stage transformer(CSFormer)as the deep denoiser to simultaneously capture self-similarity from both in-stage and cross-stage features,which is the first attempt to model the long-distance dependencies between iteration *** experiments demonstrate that the proposed maUN is superior to other state-of-the-art methods both visually and *** code is publicly available at https://***/HuQ1an/maUN.

关键词： Deep folding iteration

Gradient microstructure and superior strength-ductility synergy of AZ61 magnesium alloy bars processed by radial forging with different deformation temperatures

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Journal of materials Science & Technology 2024年第3期170卷 65-77页

作者： Jingfeng Zou Lifeng ma Yanchun Zhu Ling Qin yuan yuan School of Mechanical Engineering Taiyuan University of Science and TechnologyTaiyuan 030024China Heavy machinery Engineering Research Center of the Ministry Education Taiyuan University of Science and TechnologyTaiyuan 030024China Department of Engineering University of HullCottingham RdHull HU67RXUK National Engineering Research Center for magnesium Alloys Chongqing UniversityChongqing 400044China

Gradient microstructure modification is a cost-efficient strategy for high strength without compromising ductility,which is urgently needed in the fundamental science of engineering *** this study,heterogeneous structures of AZ61 alloy bars with anisotropic gradients(with different grain size distributions from the surface to the center)were observed to exhibit strong strength-ductility synergies under different deformation tem *** results reveal that the grain refinement process under mediumlow temperature deformation conditions(≤350℃)consists of four transition stages along the radial direction,i.e.,twin activations and deformation band formations,dislocation cells and pile-ups,ultrafine sub-grains,and randomly orientated quasi-micron *** deformation temperatures have a great influence on twin activations and deformation band formations,and the high temperature can easily provoke the initiation of non-basal *** deformation bands were determined as a primary nucleation site due to their highly unstable dislocation hindrance *** in combination with the Radial forging(RF)deformation process,the differences of dynamic precipitates can be attributed to microstructural difference and solubility limit of Al at different tem *** summarizing the tensile test results,the sample forged at 350℃exhibited the best strength-ductility synergy,exhibiting the highest elongation(EL)of 23.2%with a 251 MPa yield strength(YS)and 394 MPa ultimate tensile strength(UTS)in center region,and combined with the highest strength value of 256 MPa YS and 420 MPa UTS in the center region,while the EL was slightly degraded to 19.8%.

关键词： Gradient microstructure Radial forging Strength-ductility synergy magnesium alloy Strengthening mechanism

Hydration lubrication modulated by water structure at TiO2–aqueous interfaces

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Friction 2024年第4期12卷 591-605页

作者： Pingsu ma yuan LIU Ke HAN Yu TIAN Liran ma State Key Laboratory of Tribology in Advanced Equipment Department of Mechanical EngineeringTsinghua UniversityBeijing 100084China

The nature of solid-liquid interfaces is of great significance in *** advances have been made in lubrication based on hydration ***,a detailed molecular-level understanding is still ***,we investigated water molecule behaviors at the TiO2-aqueous interfaces by the sum-frequency generation vibrational spectroscopy(SFG-VS)and atomic force microscope(AFM)to elucidate the fundamental role of solid-liquid interfaces in *** contributions of water structures and hydration effects were revealed,where water structures played the dominant role in lubrication for TiO2 surfaces of varying hydrophilicity,while hydration effects dominated with the increasing of ion *** lubrication is observed on the initial TiO2 surfaces with strongly H-bonded water molecules compared to the hydrophilic TiO2 surfaces with more disordered *** stable ordered water arrangement with strong hydrogen bonds and the shear plane occurring between the ordered water layer and subsequent water layer may play a significant role in achieving lower *** adsorbed hydrated molecules with the increasing ionic concentration perturb ordered water but lead to the enhancement of hydration effects,which is the main reason for the improved lubrication for both *** work provides more insights into the detailed molecular-level understanding of the mechanism of hydration lubrication.

关键词： hydration lubrication interfacial water structures hydration effects titanium dioxide(TiO2)

Association of plasma vitamin A level with type 2 diabetes mellitus:a community aging population-based cross-sectional study

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Food Science and Human Wellness 2024年第4期13卷 2079-2089页

作者： Pengfei Li Jingjing Xu Yujie Guo Xiaojun ma Shaobo Zhou chi Zhang Huiyan Yu Ying Wang Xixiang Wang Linhong yuan School of Public Health Beijing Key Laboratory of Environmental ToxicologyChina-British Joint Laboratory of Nutrition Prevention and Control of Chronic DiseasesCapital Medical UniversityBeijing 100069China School of Science Faculty of Engineering and ScienceUniversity of GreenwichChatham ME44TBUK School of Biological Sciences University of Nebraska-LincolnNE 68588-0660USA Suzhou Hospital Affiliated Hospital of Medical SchoolNanjing UniversitySuzhou 215153China

Recent studies indicated that vitamin A(VA)might be involved in the pathology of type 2 diabetes mellitus(T2DM).This cross-sectional study was conducted to explore the association between circulating VA level and T2DM.A total of 1818 subjects aged 50 years old and above were recruited from the *** logistic regression and restricted cubic spline(RCS)were applied to analyze the association of plasma VA level with the risk of *** VA and lipid-adjusted VA levels of T2DM patients were significantly higher than that of non-T2DM subjects(Pma VA/total cholesterol(TC),VA/high-density lipoprotein cholesterol(HDL-c)and VA/low-density lipoprotein cholesterol(LDL-c)were positively associated with the risk of T2DM in the aging population(Pma VA/triglyceride(TG)have decreased risk of T2DM(odds ratio(OR)Q2=0.68,P_(Q2)=0.021;ORQ3=0.59,P_(Q3)ma VA/TC,VA/HDL-c,and VA/LDL-c displayed increased risk for T2DM,but the moderate ratio of VA/TG might protect against risk of T2DM.

关键词： Type 2 diabetes mellitus Vitamin A Lipid Nutrition Disease prevention

Event-triggered finite-time command-filtered tracking control for nonlinear time-delay cyber physical systems against cyber attacks

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Frontiers of Information Technology & Electronic Engineering 2024年第2期25卷 225-236页

作者： Yajing ma yuan WANG Zhanjie LI Xiangpeng XIE School of Internet of Things Nanjing University of Posts and TelecommunicationsNanjing210003China Institute of Advanced Technology for Carbon NeutralityNanjing University of Posts and TelecommunicationsNanjing210023China

This article addresses the secure finite-time tracking problem via event-triggered command-filtered control for nonlinear time-delay cyber physical systems(CPSs)subject to cyber *** the attack circumstance,the output and state information of CPSs is unavailable for the feedback design,and the classical coordinate conversion of the iterative process is incompetent in relation to the tracking *** solve this,a new coordinate conversion is proposed by considering the attack gains and the reference signal *** employing the transformed variables,a modified fractional-order command-filtered signal is incorporated to overcome the complexity explosion issue,and the Nussbaum function is used to tackle the varying attack *** systematically constructing the Lyapunov-Krasovskii functional,an adaptive event-triggered mechanism is presented in detail,with which the communication resources are greatly saved,and the finite-time tracking of CPSs under cyber attacks is ***,an example demonstrates the effectiveness.

关键词： Cyber physical systems Finite-time tracking Event-triggered Command-filtered control Attacks

Hydrologic Response to Future Climate Change in the Dulong-Irra-waddy River Basin Based on Coupled Model Intercomparison Project 6

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chinese Geographical Science 2024年第2期34卷 294-310页

作者： XU Ziyue ma Kai yuan Xu HE Daming Institute of International Rivers and Eco-security Yunnan UniversityKunming 650500China Yunnan Key Laboratory of International Rivers and Transboundary Eco-security Kunming 650500China

Within the context of the Belt and Road Initiative(BRI)and the china-Myanmar Economic Corridor(CMEC),the Dulong-Ir-rawaddy(Ayeyarwady)River,an international river among china,India and Myanmar,plays a significant role as both a valuable hydro-power resource and an essential ecological ***,the water resources and security exhibit a high degree of vulnerabil-ity to climate change *** research evaluates climate impacts on the hydrology of the Dulong-Irrawaddy River Basin(DIRB)by using a physical-based hydrologic *** crafted future climate scenarios using the three latest global climate models(GCMs)from Coupled Model Intercomparison Project 6(CMIP6)under two shared socioeconomic pathways(SSP2-4.5 and SSP5-8.5)for the near(2025-2049),mid(2050-2074),and far future(2075-2099).The regional model using MIKE SHE based on historical hydrologic processes was developed to further project future streamflow,demonstrating reliable performance in streamflow simulations with a val-idation Nash-Sutcliffe Efficiency(NSE)of *** showed that climate change projections showed increases in the annual precip-itation and potential evapotranspiration(PET),with precipitation increasing by 11.3%and 26.1%,and PET increasing by 3.2%and 4.9%,respectively,by the end of the century under SSP2-4.5 and *** changes are projected to result in increased annual streamflow at all stations,notably at the basin’s outlet(Pyay station)compared to the baseline period(with an increase of 16.1%and 37.0%at the end of the 21st century under SSP2-4.5 and SSP5-8.5,respectively).Seasonal analysis for Pyay station forecasts an in-crease in dry-season streamflow by 31.3%-48.9%and 22.5%-76.3%under SSP2-4.5 and SSP5-8.5,respectively,and an increase in wet-season streamflow by 5.8%-12.6%and 2.8%-33.3%,***,the magnitude and frequency of flood events are pre-dicted to escalate,potentially impacting hydropower production and food security *** res

关键词： climate change hydrologic response Coupled Model Intercomparison Project 6(CMIP6) MIKE SHE(Système Hydrologique Europeén) Dulong-Irrawaddy River Basin

Analytical solution for the effective elastic properties of rocks with the tilted penny-shaped cracks in the transversely isotropic background

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Petroleum Science 2024年第1期21卷 221-243页

作者： Zheng-Qian ma Xing-Yao Yin Zhao-Yun Zong yuan-yuan Tan Ya-Ming Yang National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao266580ShandongChina School of Geosciences China University of Petroleum(East China)Qingdao 266580ShandongChina Pilot National Laboratory for marine Science and Technology(Qingdao) Qingdao266200ShandongChina

Seismic prediction of cracks is of great significance in many disciplines,for which the rock physics model is ***,up to now,multitudinous analytical models focus primarily on the cracked rock with the isotropic background,while the explicit model for the cracked rock with the anisotropic background is rarely investigated in spite of such case being often encountered in the ***,we first studied dependences of the crack opening displacement tensors on the crack dip angle in the coordinate systems formed by symmetry planes of the crack and the background anisotropy,respectively,by forty groups of numerical *** on the conclusion from the experiments,the analytical solution was derived for the effective elastic properties of the rock with the inclined penny-shaped cracks in the transversely isotropic ***,we comprehensively analyzed,according to the developed model,effects of the crack dip angle,background anisotropy,filling fluid and crack density on the effective elastic properties of the cracked *** analysis results indicate that the dip angle and background anisotropy can significantly either enhance or weaken the anisotropy degrees of the P-and SH-wave velocities,whereas they have relatively small effects on the SV-wave velocity ***,the filling fluid can increase the stiffness coefficients related to the compressional modulus by reducing crack compliance parameters,while its effects on shear coefficients depend on the crack dip *** increasing crack density reduces velocities of the dry rock,and decreasing rates of the velocities are affected by the crack dip *** comparing with exact numerical results and experimental data,it was demonstrated that the proposed model can achieve high-precision estimations of stiffness ***,the assumption of the weakly anisotropic background results in the consistency between the proposed model and Hudson's published theory for the or

关键词： Effective elastic property Tilted crack Transverse isotropy Analytical solution Crack opening displacement

Thermogravimetric characteristics of corn straw and bituminous coal copyrolysis based the ilmenite oxygen carriers

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chinese Journal of Chemical Engineering 2024年第4期68卷 8-15页

作者： Pengxing yuan Xiude Hu Jingjing ma Tuo Guo Qingjie Guo College of Chemical Engineering Qingdao University of Science&TechnologyQingdao 266042China State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering Ningxia UniversityYinchuan 750021China

Herein,the co-pyrolysis reaction characteristics of corn straw(CS)and bituminous coal in the presence of ilmenite oxygen carriers(OCs)are investigated via thermogravimetry coupled with mass *** results reveal that the participation of OCs weakens the devolatilization intensity of *** the CS blending ratio is<50%,the mixed fuel exhibits positive synergistic *** fitting results according to the Coats-Redfern integral method show that the solid-solid interaction between OCs and coke changes the reaction kinetics,enhancing the co-pyrolysis reactivity at the high-temperature zone(750-950C).The synergistic effect is most prominent at a 30%CS blending ratio,with copyrolysis activation energy in the range of 26.35-40.57 kJ·mol^(-1).

关键词： Oxygen carrier Co-pyrolysis Biomass Coal

Alternative technology for the recovery of butyl acetate with low concentration:high capacity adsorbent and high efficiency adsorption

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Green Chemical Engineering 2024年第2期5卷 236-244页

作者： chi ma Lihong Zhao Zhengxin mao Hao Su Qingfen Liu CAS Key Laboratory of Green Process and Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing100049China

Industrial pharmaceutical wastewater usually contains butyl acetate(BA)with a concentration of 1 wt%-7 wt%,and the traditional method for BA recovery is distillation with high energy *** method is developed to recover BA with low concentration for the high efficiency and low energy *** polar polyacrylate resins with macroporous structure of 233.1 nm and average particle size of about 526.5μm are successfully synthesized by suspension polymerization and used for the BA adsorption and *** maximum adsorption capacity reaches 171.1 mg g^(-1)with relative standard deviation(RSD)value of 0.2%,which is more than twice the results in the *** BA desorption rate is 97.0%at 100℃with RSD value of 0.4%,and the resins are beneficial to the reuse in the adsorption-desorption *** adsorption thermodynamics and kinetics are investigated,and the BA adsorption is a spontaneous and endothermic process with the increase of disorder *** process is mainly contributed by physical absorption and agree well with Freundlich model and pseudo-first-order adsorption kinetic *** adsorption method avoids boiling a large amount of wastewater and hopefully provides a novel alternative technology for the BA recovery.

关键词： Butyl acetate recovery Resin adsorption Desorption Thermodynamics Kinetics