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Consensus control of multi-manipulator systems based on disturbance observer under Markov switching topologies

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Control Theory and Technology 2021年第2期19卷 273-282页

作者： Chang-E ren Quanxin fu College of Information Engineering Capital Normal UniversityBeijing100089China

In this paper,to solve the consensus control problem of multi-manipulator systems under Markov switching topologies,we propose a distributed consensus control strategy based on disturbance *** multi-manipulator systems,external disturbance described by heterogeneous exogenous systems is considered,and all communication topologies are ***,a disturbance observer is presented to suppress the influence of unknown external disturbance,and the equivalent compensation is introduced into the control protocol in multi-manipulator ***,a novel control protocol based on neighbor information is designed,which guarantees that multi-manipulator systems reach consensus under Markov switching ***,two simulation examples verify the validity of the theoretical result.

关键词： Multi-manipulator systems Disturbance observer Markov switching topologies Consensus control

Improving accuracy of damage quantification based on two-level consistency control of PZT layers

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Chinese Journal of Aeronautics 2023年第3期36卷 241-253页

作者： yuanqiang ren Qiuhui XU Shenfang yuan Research Center of Structural Health Monitoring and Prognosis State Key Lab of Mechanics and Control of Mechanical StructuresNanjing University of Aeronautics and AstronauticsNanjing 210016China

Structural health monitoring-based quantitative damage diagnosis technique plays a key role in real-time condition *** the current research,piezoelectric(PZT)sensor and Guided Wave(GW)based damage quantification methods are promising,which normally establish a calibration model between GW feature and damage degree by experiments on batch specimens,and then conduct the calibration model on the monitored ***,the accuracy of PZT and GW based damage quantification is affected by dispersion introduced by sensor network performance,structural material,and damage propagation among the adopted batch *** improving the accuracy of damage quantification,this paper adopts PZT layer as sensor network and creatively implements theoretical and experimental research on batch PZT layers consistency *** one hand,a two-level consistency control method based on multidimensional features-Euclidean distance is proposed to ensure the performance consistency of PZT layers placed on different *** the other hand,experimental research on typical aircraft lug structures is also carried out to evaluate the requirement on performance consistency of PZT layers when performing quantitative damage diagnosis,and further verify the proposed two-level consistency control *** results show that the accuracy of damage quantification raises by 38% when the dispersion of different PZT layers is controlled within 5%.

关键词： Consistency control Guided waves PZT layer Quantitative damage diagnosis Structural health monitoring

A fully nonlinear approach for efficient ship-wave simulation

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Journal of Hydrodynamics 2023年第6期35卷 1027-1040页

作者： Kai-yuan Shi ren-chuan Zhu School of Naval Architecture Ocean and Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China

This paper presents an efficient time-domain method for simulating nonlinear ship *** proposed method,implemented in an earth-fixed coordinate system,integrates a compact boundary element domain within a high-order spectral layer,enabling accurate modeling of both near-field and far-field ship *** overset mesh method and an attention mechanism are employed to track the moving *** effectiveness of the method is validated through simulations of Wigley and Series 60 ships sailing at various *** numerical results,including the nonlinear wave run-up at the ship bow,surface pressure distribution on the hull,and the ship resistance,agree well with experimental data and published numerical results,confirming that the method is capable of accurately simulating the nonlinear ship waves.

关键词： fully nonlinear ship wake potential flow spectral coupled method wave-making resistance

Unveiling the dynamic instability mechanism of microstructure transformation in faceted oxide eutectic composite ceramics

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Journal of Materials Science & Technology 2023年第13期144卷 224-234页

作者： Haijun Su yuan Liu Qun ren Zhonglin Shen Min Guo Xi Li Jun Zhang Lin Liu Hengzhi fu State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China Research&Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen 518057China Department of Material Science and Engineering Shanghai UniversityShanghai 200072China

Microstructure control is a great challenge in the high-temperature gradient directional solidification of eutectic composite ceramics due to the complex solidification ***,the microstructure trans-formation of faceted Al_(2)O_(3)/Er_(3)Al_(5)O_(12) thermal emission eutectic composite ceramics is explored over wide ranges of compositions(13.5 mol%-22.5 mol%Er_(2)O_(3))and solidification rates(2-200μm/s).Entirely cou-pled eutectics with primary phases suppressed are fabricated and the coupled zone is broadened in a wide range of 15.5 mol%-22.5 mol%Er_(2)O_(3) at low solidification *** competitive growth between eutectic and dendrite is evaluated on the basis of the maximum interface temperature *** ad-dition,the mechanisms of irregular eutectic spacing selection and adjustment under different solidifi-cation rates are revealed based on Magnin-Kurz model.A successful prediction of lamellar to rod-like eutectics is achieved associated with the dynamic instability of lamellar eutectic and the corresponding enlarged coexistence region is mapped based on the interface *** to the well mi-crostructure tailoring,the flexural strength of Al_(2)O_(3)/Er_(3)Al_(5)O_(12) eutectic composite ceramics has improved from 508 MPa up to 1800 MPa due to the refined eutectic spacing with low *** eutectic composite ceramics show strong selective optical absorption and the intensity increases with the refin-ing *** as-designed Al_(2)O_(3)/Er_(3)Al_(5)O_(12) composites with microstructural tailoring have great potential as integrations of structural and functional materials.

关键词： Directional solidification Laser floating zone melting Al_(2)O_(3)/Er_(3)Al_(5)O_(12)eutectic composite ceramics Eutectic growth mechanism Microstructure transformation

Development of component stiffness equations for thread-fixed one-side bolt connections to an enclosed rectangular hollow section column under tension

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Frontiers of Structural and Civil Engineering 2024年第4期18卷 568-586页

作者： fu-Wei WU yuan-Qi LI Department of Structural Engineering Tongji UniversityShanghai 200092China State Key Laboratory of Disaster Reduction in Civil Engineering Tongji UniversityShanghai 200092China

The derivation and validation of analytical equations for predicting the tensile initial stiffness of threadfixed one-side bolts(TOBs),connected to enclosed rectangular hollow section(RHS)columns,is presented in this *** unknown stiffness components are considered:the TOBs connection and the enclosed RHS ***,the trapezoidal thread of TOB,as an equivalent cantilevered beam subjected to uniformly distributed loads,is analyzed to determine the associated *** on the findings,the thread-shank serial-parallel stiffness model of TOB connection is *** analysis of the tensile stiffness of the enclosed RHS face due to two bolt forces,the four sidewalls are treated as rotation constraints,thus reducing the problem to a two-dimensional plate *** to the load superposition method,the deflection of the face plate is resolved into three components under various boundary and load *** to the plate deflection theory of Timoshenko,the analytical solutions for the three deflections are derived in terms of the variables of bolt spacing,RHS thickness,height to width ratio,***,the validity of the above stiffness equations is verified by a series of finite element(FE)models of T-stub *** proposed component stiffness equations are an effective supplement to the component-based method.

关键词： initial stiffness component based method thread-fixed one-side bolt rectangular hollow sections analytical equation

Effect of ternary transition metal sulfide FeNi_(2)S_(4)on hydrogen storage performance of MgH_(2)

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Journal of Magnesium and Alloys 2023年第8期11卷 2927-2938页

作者： Yaokun fu Lu Zhang yuan Li Sanyang Guo Han Yu Wenfeng Wang Kailiang ren Wei Zhang Shumin Han State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004China Hebei Key Laboratory of Applied Chemistry School of Environmental and Chemical EngineeringYanshan UniversityQinhuangdao 066004China

Hydrogen storage is a key link in hydrogen economy,where solid-state hydrogen storage is considered as the most promising approach because it can meet the requirement of high density and ***,magnesium-based materials(MgH_(2))are currently deemed as an attractive candidate due to the potentially high hydrogen storage density(7.6 wt%),however,the stable thermodynamics and slow kinetics limit the practical *** this study,we design a ternary transition metal sulfide FeNi_(2)S_(4)with a hollow balloon structure as a catalyst of MgH_(2)to address the above issues by constructing a MgH_(2)/Mg_(2)NiH_(4)-MgS/Fe ***,the dehydrogenation/hydrogenation of MgH_(2)has been significantly improved due to the synergistic catalysis of active species of Mg_(2)Ni/Mg_(2)NiH_(4),MgS and Fe originated from the MgH_(2)-FeNi_(2)S_(4)*** hydrogen absorption capacity of the MgH_(2)-FeNi_(2)S_(4)composite reaches to 4.02 wt%at 373 K for 1 h,a sharp contrast to the milled-MgH_(2)(0.67 wt%).In terms of dehydrogenation process,the initial dehydrogenation temperature of the composite is 80 K lower than that of the milled-MgH_(2),and the dehydrogenation activation energy decreases by 95.7 kJ·mol-1 compared with the milled-MgH_(2)(161.2 kJ·mol^(-1)).This method provides a new strategy for improving the dehydrogenation/hydrogenation performance of the MgH_(2)material.

关键词： Hydrogen storage materials Magnesium hydride FeNi_(2)S_(4) Hydrogen storage kinetics Catalysts

Catalytic effect of MOF-derived transition metal catalyst FeCoS@C on hydrogen storage of magnesium

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Journal of Materials Science & Technology 2023年第7期138卷 59-69页

作者： Yaokun fu Lu Zhang yuan Li Sanyang Guo Zhichao Yu Wenfeng Wang Kailiang ren Qiuming Peng Shumin Han State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004China Hebei Key Laboratory of Applied Chemistry School of Environmental and Chemical EngineeringYanshan UniversityQinhuangdao 066004China

The introduction of the heterogeneous catalysts with high activity can significantly improve hydrogen storage performance of MgH_(2),therefore,in this paper,we synthesize a carbon-supported transition metal compound,FeCoS@C derivative from ZIF-67,by utilizing the in situ formed C dispersive multiphase Mg_(2)Co,α-Fe,Co_(3)Fe_(7),and MgS to implement catalysis to MgH_(2).Noteworthily,MgH_(2)-FeCoS@C rapidly ab-sorbs 6.78 wt%H_(2)within 60 s at 573 K and can also absorb 4.56 wt%H_(2)in 900 s at 473 ***,the addition of FeCoS@C results in decreasing of the initial dehydrogenation temperatures of MgH_(2)from 620 to 550 *** dehydrogenation activation energy of MgH_(2)decreases from 160.7 to 91.9 kJ mol^(-1).Studies show that the Mg_(2)Co,α-Fe,and Co_(3)Fe_(7)act as“hydrogen channels”to accelerate hydrogen transfer due to the presence of transition metals,and MgS with excellent catalytic effect formed from MgH_(2)-FeCoS@C provides a strong and stable catalytic ***,the carbon skeleton obtained by the carbonization of ZIF-67 not only serves as a dispersion for the multiphase catalytic system,but also provides more active sites for the *** study shows that the multiphase and multiscale catalytic system provides an effective strategy for improving the hydrogen storage performance of MgH_(2).

关键词： Hydrogen storage material Magnesium hydride Heterogeneous catalyst Synergistic catalytic MOF materials

Considerations on the concept, definition, and diagnosis of amyotrophic lateral sclerosis

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Neural Regeneration Research 2021年第9期16卷 1723-1729页

作者： ren-Shi Xu Min yuan Department of Neurology Jiangxi provincial People’s HospitalAffiliated People’s Hospital of Nanchang UniversityNanchangJiangxi ProvinceChina

The concept, definition, and diagnosis of amyotrophic lateral sclerosis(ALS) currently present some problems. This article systematically reviews the literature on the history, current concepts, definition, and diagnosis of ALS, and discloses the present problems based on the retrieved literature and the authors' clinical experience. The current concepts and definitions of ALS have not yet been unified or standardized in clinical practice, and are sometimes vague or inaccurate, which can cause difficulties for neurologists in the clinical treatment of ALS. The concept and definition of ALS need to be further ascertained, and the current diagnostic criteria for ALS require further development. The identification of effective and objective biomarkers may be a feasible method for the early and accurate diagnosis of ALS. Therefore, future research should focus on the identification of reliable biomarkers—especially neuroimaging biomarkers—through autopsy. Standardizing the concept and definition of ALS and formulating clear diagnostic criteria will largely avoid many uncertainties in the future clinical research and treatment of ALS, which will greatly benefit patients.

关键词： amyotrophic lateral sclerosis clinical symptoms concept definition diagnosis familial amyotrophic lateral sclerosis motor neuron disease muscle atrophy

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创伤后应激障碍的网络化心理干预及起效机制

心理科学进展 2025年第1期33卷 123-135页

作者：杜夏雨赛力古·亚力坤袁洁莹任志洪青少年网络心理与行为教育部重点实验室人的发展与心理健康湖北省重点实验室华中师范大学心理学院华中师范大学国家智能社会治理实验基地(教育)武汉430079

创伤后应激障碍是一种高度痛苦且致残的心理疾病,在全球范围内造成了重大的健康负担。网络化心理干预因其易得性和匿名性等特征,被广泛应用于创伤后应激障碍的治疗领域。本研究综述了“自上而下”和“自下而上”的网络化心理干预方法及... 详细信息

创伤后应激障碍是一种高度痛苦且致残的心理疾病,在全球范围内造成了重大的健康负担。网络化心理干预因其易得性和匿名性等特征,被广泛应用于创伤后应激障碍的治疗领域。本研究综述了“自上而下”和“自下而上”的网络化心理干预方法及其效果,发现大部分干预措施对于创伤后应激障碍具有良好的效果。为了深入探究干预起效的心理机制,本研究构建了网络化干预创伤后应激障碍的双重机制模型,即基于认知重构的认知行为疗法模型和基于认知歪曲的认知偏向矫正模型,为创伤后应激障碍的网络化干预提供理论和实践指导。未来研究中,可以引入聊天机器人和虚拟仿真工具等技术,为用户提供即时支持和个性化干预,实现更全面的数字化干预流程,提升创伤后应激障碍的网络化干预效果和效率。

关键词：创伤后应激障碍网络化心理干预效果作用机制

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