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Distributed consensus for multiple Euler-Lagrange systems: An event-triggered approach

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Science China(Technological Sciences) 2016年第1期59卷 33-44页

作者： huang na DUAN ZhiSheng ZHAO Yu State Key Laboratory for Turbulence and Complex Systems Department of Mechanics and Engineering Science College of EngineeringPeking University

Distributed consensus problems for multiple Euler-Lagrange systems are addressed on the basis of event-triggered information in this study. Distributed consensus protocols are first designed in terms of two event-triggered scenarios: a decentralized strategy and a distributed strategy. Sufficient conditions that guarantee the event-triggered consensus for multiple Euler-Lagrange systems are then presented, with the associated advantages of reducing controller update times. It is shown that the Zeno behavior of triggering time sequences is excluded for both strategies. Finally, multiple Euler-Lagrange systems that consist of six two-link manipulators are considered to illustrate the effectiveness of the proposed theoretical algorithms.

关键词： consensus event-triggered strategy Euler-Lagrange system distributed control

STABILIZED BARZILAI-BORWEIN METHOD

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Journal of Computational Mathematics 2019年第6期37卷 916-936页

作者： Oleg Burdakov Yuhong Dai na huang Department of Mathematics Linkoping UniversityLinkopingSweden LSEC ICMSECAcademy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China Department of Applied Mathematics College of ScienceChina Agricultural UniversityBeijing 100083China

The Barzilai-Borwein(BB)method is a popular and efficient tool for solving large-scale unconstrained optimization *** search direction is the same as for the steepest descent(Cauchy)method,but its stepsize rule is *** to this,it converges much faster than the Cauchy method.A feature of the BB method is that it may generate too long steps,which throw the iterates too far away from the ***,it may not converge,even when the objective function is strongly *** this paper,a stabilization technique is *** consists in bounding the distance between each pair of successive iterates,which often allows for decreasing the number of BB *** the BB met hod does not converge,our simple modification of this method makes it *** strongly convex functions with Lipsch计s gradients,we prove its global convergence,despite the fact that no line search is involved,and only gradient values are *** the number of stabilization steps is proved to be finite,the stabilized version inherits the fast local convergence of the BB met *** presented results of extensive numerical experiments show that our stabilization technique often allows the BB method to solve problems in a fewer计erations,or even to solve problems where the latter fails.

关键词： Unconstrained optimization Spectral algorithms Stabilization Convergence analysis.

Synthesis, Structures and Properties of Three New Compounds Based on Multidentate Ligand Containing Triazole and Pyrimidine

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Chemical Research in Chinese Universities 2015年第5期31卷 712-718页

作者： LU Lei MU Bao LI na huang Rudan Key Laboratory of Cluster Science Ministry of Education Department of Chemistry Beijing Institute of Technology Beijing 100081 P. R.China

Three new compounds, namely, [Zn（mtpo）2（H2O）4]（l）, [Cd（mtpo）2-CH3CH2OH].（2） and [Mn（mtpo）2·CH3CH2OH]n（3）（Hmtpo=4,7-dihydro-5-methyl-7-oxo-[1,2,4]triazolo[1,5-a]pyrimidine）, have been synthesized via hydrothermal or solvothermal methods and characterized by means of elemental analyses, Fourier transform infrared（FYIR） spectroscopy, powder X-ray diffraction（PXRD）, thermogravimetric analysis（TGA） and single-crystal X-ray diffraction. The results obtained from the single-crystal X-ray diffraction indicate that compound 1 has a mononuclear structure, and crystallizes in a monoclinic crystal system with P21/c space group, which exhibits a 2D supramolecular network constructed by hydrogen bonds and π-π interactions. Compounds 2 and 3 are isomorphous and crystallize in a tetragonal system with space group of I41/a. The M^2＋（M=Cd, Mn） ions in compounds 2 and 3 have the octahedral coordination geometry. Hmtpo acts as a bridging ligand linking the metal ions to form an infinite 3D framework with 4-connected {4^2·8^4} topology. There are hydrogen bonds between the guest ethanol molecules and the mtpo ligands, which make the ethanol molecules exist in a 3D framework. In addition, luminescent properties of compounds 1 and 2 as well as magnetic property of compound 3 were investigated and water vapor adsorption and nitrogen sorption for compounds 2 and 3 were researched at 298 and 77 K, respectively.

关键词： Metal-organic framework(MOF) Hydrogen bond Luminescent property Magnetic property Water vapor sorption Nitrogen sorption

Synthesis and characterization of biodegradable materials:PDLLA-(MAh-Diol)_n-PDLLA copolymer

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Chinese Chemical Letters 2007年第5期18卷 613-616页

作者： Jia Chen Yuan Liang Wang Mei na huang Research Center of Bioinspired Material Science and Engineering （BIMSEC） College of Bioengineering Chongqing University Chongqing 400044 PR China

The novel biodegradable copolymer PDLLA-（MAH-Diol）n-PDLLA with unsaturated bond was synthesized by copolymefizing lactide and prepolymer, which was prepared by the polycondensation of maleic anhydride and poly（ethylene glycol）, using ptoluene sulphonic acid as catalyst. The new copolymer has improved hydrophilicity and flexibility. The structure and properties of the novel polymers were studied by FTIR, NMR, GPC-MALLS and DSC.

关键词： Poly(ethylene glycol) Maleic anhydride PDLLA-(MAH-Diol)n-PDLLA Unsaturated bond

Distributed Observers Design for Leader-Following Control of Nonlinear Multi-agent Systems with Heterogeneous Topologies 36

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Distributed Observers Design for Leader-Following Control of...

Three-dimensional double-rough-walled modeling of fluid flow through self-affine shear fractures

第36届中国控制会议

作者： ShiJie Zhao Li Gao na huang Hangzhou Danzi University School of Automation

ISBN: (纸本)9781538629185

This paper focuses on consensus of multi-agent systems with leader-following and unknown nonlinear dynamics under heterogenous *** of all,we give a control algorithm for the condition that the system without leader under heterogeneous *** conditions in terms of linear matrix inequality（LMI） are established to guarantee distributed consensus of multi-agent *** second,we design distributed observers for the leader-following control of the multiagent *** Lyapunov function（CLF） method is applied to prove consensus of system with and without nonlinear *** simulation are provides to show that the states of all agents can reach consensus under proposed control laws.

关键词： Multi-agent systems Nonlinear dynamics Heterogeneous topologies

来源： cnki会议评论

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Journal of Rock Mechanics and Geotechnical Engineering 2020年第1期12卷 41-49页

作者： Richeng Liu Ming He na huang Yujing Jiang Liyuan Yu State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and TechnologyXuzhou221116China School of Engineering Nagasaki UniversityNagasaki852-8521Japan School of Petroleum Engineering China University of PetroleumQingdao266580China

This study proposes a double-rough-walled fracture model to represent the natural geometries of rough *** rough surface is generated using a modified successive random additions(SRA)algorithm and the aperture distribution during shearing is calculated using a mechanistic *** shear-flow simulations are performed by directly solving the navier-Stokes(NS)*** results show that the double-rough-walled fracture model can improve the accuracy of fluid flow simulations by approximately 14.99%-19.77%,compared with the commonly used single-rough-walled fracture *** ratio of flow rate to hydraulic gradient increases by one order of magnitude for fluids in a linear flow regime with increment of shear displacement from 2.2 mm to 2.6 *** solving the NS equations,the inertial effect is taken into account and the significant eddies are simulated and numerically visualized,which are not easy to be captured in conventional *** anisotropy of fluid flow in the linear regime during shearing is robustly enhanced as the shearing advances;however,it is either increased or decreased for fluids in the nonlinear flow regime,depending on the geometry of shear-induced void spaces between the two rough walls of the *** present study provides a method to represent the real geometry of fractures during shearing and to simulate fluid flow by directly solving the NS equations,which can be potentially utilized in many applications such as heat and mass transfer,contaminant transport,and coupled hydro-thermo-mechanical processes within rock fractures/fracture networks.

关键词： Double-rough-walled fracture navier-Stokes(NS)equations Anisotropy Fractal dimension

Interfacial growth of N,S-codoped mesoporous carbon onto biomass-derived carbon for superior potassium-ion storage

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nano Research 2024年第4期17卷 2619-2627页

作者： na huang Cheng Tang Hao Jiang Jie Sun Aijun Du Haijiao Zhang Institute of nanochemistry and nanobiology School of Environmental and Chemical EngineeringShanghai UniversityShanghai 200444China School of Chemistry and Physics and Centre for Materials Science Queensland University of TechnologyBrisbaneQLD 4001Australia Shanghai Engineering Research Center of Hierarchical nanomaterials Frontiers Science Center for Materiobiology and Dynamic ChemistrySchool of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China

Carbonaceous materials have been recognized as one of the most promising anode materials for potassium-ion batteries(PIBs)due to their abundant raw materials,controllable structure,superior conductivity,and good chemical ***,the large radius of K ions and the low potassium content of intercalation compounds result in the sluggish storage kinetics and low reversible capacity of carbon *** this work,we present a unique heteroatom-doped carbon composite(denoted as NS-MC/SC)through a facile interfacial assembly route and simple heat-treatment process,where NS-MC is well grafted onto the biomass-derived spore carbon(SC).This unique structural design endows it with abundant mesoporous channels,expanded layer spacing,and highly doped N and *** these merits,the NS-MC/SC anode in PIBs exhibits a high reversible capacity of 350.4 mAh·g^(-1) at 100 mA·g^(-1) after 300 cycles,and an outstanding cycling ***,in-situ Raman spectra further verify the high reversibility of K ions insertion/***,theoretical simulations also reveal that the N,S dual-doping is an efficient approach for improving the potassium-ion storage performance of NS-MC/SC.

关键词： mesoporous carbon(MC) biomass-derived carbon(BC) N S co-doping interfacial assembly potassium-ion batteries(PIBs)

Influences of Hot-Isostatic-Pressing Temperature on the Microstructure, Tensile Properties and Tensile Fracture Mode of 2A12 Powder Compact

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Acta Metallurgica Sinica(English Letters) 2016年第10期29卷 963-974页

作者： Gang Wang Li-Hui Lang Wen-Jun Yu Xi-na huang Fei Li School of Mechanical Engineering and Automation Beihang University Beijing 100191 China Avic Chengdu Aircraft Industrial (Group) Co. Ltd Chengdu 610000 China

2A12 aluminum alloy powders were hot-isostatic-pressed （HIPed） at representative temperatures for investi- gating the variation in microstructure, tensile property and fracture mode of the powder compact. It was found that the microstructure of raw powders changed from a dendrite structure to an equiaxed structure from room temperature to 600 ℃. The liquid phase produced by the eutectic reaction in the powder was gradually increased and finally formed a liquid pathway that ran through the entire powder from 490 to 600℃. Prior particle boundaries were observed in the powder compacts HIPed at 490 and 520℃. The liquid phase in the powder compacts was squeezed into the powder boundaries and the triple points of powder when HIPed at 580℃. However, the liquid phase located at the triple points of the powder was forced out and moved toward a small powder particle by HIP pressure under an HIPing temperature of 600℃, which led to a decrease in the mechanical properties and relative density. Better comprehensive properties were obtained at HIPing temperatures of 490 and 580℃. The low ductility exhibited by the P/M aluminum alloy HIPed at different temperatures was believed to arise from a combination of the existence of oxide film on the powder particle surface and the distribution characteristics of the liquid phase. Finally, three typical types of de-cohesion were classified.

关键词： Powder metallurgy Hot-isostatic-pressing Microstructural evolution Fracture mode Aluminum alloy Mechanical properties

Combined therapy with transcatheter arterial chemoembolization and percutaneous microwave coagulation for small hepatocellular carcinoma

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World Journal of Gastroenterology 2009年第6期15卷 748-752页

作者： Wei-Zhu Yang na Jiang Ning huang Jing-Yao huang Qu-Bin Zheng Quan Shen Interventional Radiology Department Union Hospital Fujian Medical University Fuzhou 350001 Fujian Province China

AIM:To assess the efficacy of combined transcatheter arterial chemoembolization(TACE)and percutaneous microwave coagulation therapy(PMCT)for small hepatocellular carcinoma(HCC). METHODS:Thirty-five patients with a total of 41 HCC nodules(≤3 cm in diameter)were treated with TACE followed by computed tomograghy(CT)-guided percutaneous microwave coagulation therapy(PMCT) within 1-3 wk. RESULTS:By biopsies and enhanced CT scans, complete necrosis of the tumor and 3-5 mm of the surrounding non-cancerous area were observed in 34 *** seven foci,incomplete necrosis of the surrounding parenchyma was *** alpha- fetoprotein(AFP)levels returned to normal 10 d after treatment in 25 patients who originally had high serum AFP *** follow-up period was 6-31 mo,and all patients remained *** patient had a recurrence in the subsegments of the liver,and another patient had a recurrence near the original lesion. CONCLUSION:Combined therapy with TACE and PMCT is a safe and effective treatment without severe complications for small HCC.

关键词： Liver neoplasms Therapy Hepatocellular carcinoma Transcatheter arterial chemoembolization Microwave coagulation therapy Percutaneous local treatment