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Chinese Journal of Mechanical Engineering 2024年第3期37卷 189-203页

作者： Jian Hu Zhengyin yang Jianyong yao School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210094China

Effective fault diagnosis and fault-tolerant control method for aeronautics electromechanical actuator is concerned in this *** borrowing the advantages of model-driven and data-driven methods,a fault tolerant nonsingular terminal sliding mode control method based on support vector machine(SVM)is proposed.A SVM is designed to estimate the fault by off-line learning from small sample data with solving convex quadratic programming method and is introduced into a high-gain observer,so as to improve the state estimation and fault detection accuracy when the fault *** state estimation value of the observer is used for state reconfiguration.A novel nonsingular terminal sliding mode surface is designed,and Lyapunov theorem is used to derive a parameter adaptation law and a control *** is guaranteed that the proposed controller can achieve asymptotical stability which is superior to many advanced fault-tolerant *** addition,the parameter estimation also can help to diagnose the system faults because the faults can be reflected by the parameters *** comparative simulation and experimental results illustrate the effectiveness and advancement of the proposed controller compared with several other main-stream controllers.

关键词： Aeronautics electromechanical actuator Fault tolerant control Support vector machine State observer Parametric uncertainty

Gauss optimization method for the dynamics of unilateral contact of rigid multibody systems

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Acta Mechanica Sinica 2021年第3期37卷 494-506,I0003页

作者： Wenli yao Liusong yang Mingming Guo Qingdao Key Laboratory for Geomechanics and Offshore Underground Engineering School of ScienceQingdao University of TechnologyQingdao 266520China College of Pipeline and Civil Engineering China University of Petroleum(East China)Qingdao 266520China

The discontinuous dynamical problem of multi-point contact and collision in multi-body system has always been a hot and difficult issue in this *** on the Gauss’principle of least constraint,a unified optimization model for multibody system dynamics with multi-point contact and collision is *** paper presents the study of the numerical solution scheme,in which particle swarm optimization method is used to deal with the corresponding optimization *** article also presents the comparison of the Gauss optimization method(GOM)and the hybrid linear complementarity method(*** differential algebraic equations(DAEs)and linear complementarity problems(LCP)),commonly used to solve the dynamic contact problem of multibody systems with bilateral *** results illustrate that,the GOM has the same advantage of dynamical modelling with LCP and when the redundant constraint exists,the GOM always has a unique solution and so no additional processing is needed,whereas the corresponding DAE-LCP method may have singular cases with multiple solutions or no *** numerical examples,the GOM is verified to effectively solve the dynamics of multibody systems with redundant unilateral and bilateral constraints without additional redundancy *** GOM can also be applied to the optimal control of systems in the future and combined with the parameter optimization of systems to handle dynamic *** work given provides the dynamics and control of the complex system with a new train of thought and method.

关键词： Contact Collision Redundant constraint Gauss principle of least constraint Optimization method

Shear wave velocity structure of the crust and upper mantle in Southeastern Tibet and its geodynamic implications

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Science China Earth Sciences 2020年第9期63卷 1278-1293页

作者： Zhiqi ZHANG Huajian yao Yan yang Laboratory of Seismology and Physics of Earth’s Interior School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China Mengcheng National Geophysical Observatory University of Science and Technology of ChinaMengcheng 233500China CAS Center for Excellence in Comparative Planetology USTC Hefei 230026China

Southeastern Tibet,which has complex topography and strong tectonic activity,is an important area for studying the subsurface deformation of the Tibetan *** the two-station method on 10-year teleseismic Rayleigh wave data from 132 permanent stations in the southeastern Tibetan Plateau,which incorporates ambient noise data,we obtain the interstation phase velocity dispersion data in the period range of 5–***,we invert for the shear wave velocity of the crust and upper mantle through the direct 3-D inversion *** find two low-velocity belts in the mid-lower *** belt is mainly in the SongPan-GangZi block and northwestern part of the Chuan-Dian diamond block,whereas the other belt is mainly in the Xiaojiang fault zone and its eastern part,the Yunnan-Guizhou *** low-velocity belt in the Xiaojiang fault zone is likely caused by plastic deformation or partial melting of felsic rocks due to crustal ***,the significant positive radial anisotropy(VSH>VSV)around the Xiaojiang fault zone further enhances the amplitude of low velocity anomaly in our *** crustal low-velocity zone also extends southward across the Red River fault and farther to northern Vietnam,which may be closely related to heat sources in the upper *** two low-velocity belts are separated by a high-velocity zone near the Anninghe-Zemuhe fault system,which is exactly in the inner and intermediate zones of the Emeishan large igneous province(ELIP).We find an obvious high-velocity body situated in the crust of the inner zone of the ELIP,which may represent maficultramafic material that remained in the crust when the ELIP *** the upper mantle,there is a large-scale low-velocity anomaly in the Indochina and South China blocks south of the Red River *** low-velocity anomaly gradually extends northward along the Xiaojiang fault zone into the yangtze Craton as depth *** our velocity model,we think that southeastern Tibet is

关键词： Southeastern Tibet Surface wave tomography Shear wave velocity structure Xiaojiang fault system Emeishan large igneous province Asthenospheric upwelling

Corrosion resistance behavior of gradient microstructure induced by punching deformation and recovery treatment on cupronickel alloy surface

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Rare Metals 2017年第12期36卷 971-976页

作者： Xiang-yang Mao Hao Chen Hong-Yan yang yao yao Hong-Xing Wang Jiangsu Key Laboratory of Advanced Structural Materials and Application Technology School of Materials EngineeringNanjing Institute of Technology Nanjing 211167 China

In this study, the gradient grain induced by punching deformation and recovery treatment on a cupronickel alloy surface sample were investigated, and their effects on corrosion resistance were measured by atom force microscopy(AFM), X-ray diffraction(XRD),electrochemical measurement, electron work function(EWF), and contact electrical resistance(CER). The cupronickel alloy surface experienced punching deformation for 60 min and recovery at 300 ℃ for 1 h to produce gradient surface. The grain size measured by XRD is bigger than that measured by AFM, due to X-ray intensity of95 % produced at the depth of 12-20 μm for the crystal planes of(111),(200), and(220). The gradient grain surface, compared to the original surface, shows a 13.7-fold decrease in passivation current density(i), and corrosion potential(Ec) increases by approximately 9.8 %. These results are attributable to the increase in EWF and formation of passivation film with better adhesion and compactness after treatment.

关键词： Gradient grain Corrosion resistance Electron work function Punching deformation

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棉织物的碱性抗皱整理剂AC-PBE整理

印染 2018年第6期44卷 40-43页

作者：李富强吴乾史杨洋姚金龙向中林何瑾馨东华大学化学化工与生物工程学院上海201620 江苏联发纺织股份有限公司江苏南通226000 东华大学纺织面料技术教育部重点实验室上海201620

以丙烯酰氯和对位酯为原料,合成了一种新型碱性交联剂对(β-硫酸酯乙基砜)苯丙烯酰胺(ACPBE)。通过高效液相色谱(HPLC)及核磁氢谱(1HNMR)对AC-PBE的结构进行表征。将AC-PBE用于棉织物抗皱整理,研究了整理剂和碱的质量浓度、干燥时间、... 详细信息

以丙烯酰氯和对位酯为原料,合成了一种新型碱性交联剂对(β-硫酸酯乙基砜)苯丙烯酰胺(ACPBE)。通过高效液相色谱(HPLC)及核磁氢谱(1HNMR)对AC-PBE的结构进行表征。将AC-PBE用于棉织物抗皱整理,研究了整理剂和碱的质量浓度、干燥时间、汽蒸时间、汽蒸温度和湿度对整理效果的影响。结果表明,优化的整理工艺为AC-PBE质量浓度80 g/L,碳酸钠质量浓度15 g/L,50℃烘干5 min,汽蒸温度110℃,汽蒸湿度75%,汽蒸时间5 min。将AC-PBE与多元羧酸的整理效果进行对比,发现与多元羧酸折皱回复角相同的条件下,AC-PBE整理织物的强力保留率更高。

关键词：防皱整理碱性交联折皱回复角强力保留率棉织物

Lanthanide-DNA supramolecular hydrogels with tunable and responsive luminescence

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Science China(Technological Sciences) 2022年第5期65卷 1043-1051页

作者： yang Sen PAN XiaoRui TANG JianPu yao Chi yang DaYong Frontiers Science Center for Synthetic Biology Key Laboratory of Systems Bioengineering(MOE)Institute of Biomolecular and Biomedical EngineeringSchool of Chemical Engineering and TechnologyTianjin UniversityTianjin300350China

Supramolecular DNA hydrogels have been synthesized based on the assembly of DNA building-blocks such as branched DNA and long DNA *** structures and functions of sole-module DNA hydrogels remain *** methodologies by integrating hybrid components are desired to expand the synthesis of DNA ***,we synthesized a Ln^(3+)-containing luminescent supramolecular hydrogel by employing the coordination and electrostatic interactions between lanthanide ions(Tb^(3+)and Eu^(3+))and linear single-stranded DNA(ssDNA).Through the coordination between ssDNA and Ln^(3+),a series of luminescent supramolecular hydrogels were synthesized,among which the Tb-G_(n)/T_(n)and Eu-T_(n)hydrogels emitted the characteristic luminescence of Tb and Eu,*** luminescent intensities of the hydrogels were adjusted by designing DNA sequences with programmable bases and chain ***,the Tb/Eu co-doped luminescent supramolecular hydrogel displayed tunable luminescence from green to yellow by regulating the stoichiometric ratio of Tb/***,the hydrogel had reversible luminescent stimulation responsiveness toward Ag^(+)/*** expected that the synthesis of Ln^(3+)-containing luminescent supramolecular hydrogels enriched the strategies of the construction of DNA hydrogels,and promoted the development of stimuli-responsive supramolecular materials.

关键词： DNA hydrogel supramolecular self-assembly luminescent hydrogel lanthanide complex stimuli-responsiveness

Adaptive-surrogate-based robust optimization of transonic natural laminar flow nacelle

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Chinese Journal of Aeronautics 2021年第10期34卷 36-52页

作者： Yuan yao Dongli MA Muqing yang Liang ZHANG yang GUO School of Aeronautic Science and Engineering Beihang UniversityBeijing 100083China

Natural Laminar Flow(NLF)technology is very effective for reducing the skin friction drag of aircraft engine nacelle,but the aerodynamic performance of NLF nacelle is highly sensitive to uncertain working ***,it’s imperative to incorporate uncertainties into the design of NLF *** this study,for a robust optimization of NLF nacelle and for improving its efficiency,an adaptive-surrogate-based robust optimization strategy is established,which is an iterative optimization process where the surrogate model is updated to obtain the real Pareto front of multi-objective optimization problem.A case study is carried out to validate its feasibility and *** results show that the optimization increases the favorable pressure gradient region and the volume ratio of the nacelle by increasing its lip radius and reducing its maximum *** the aerodynamic robustness of the NLF nacelle is mainly determined by the lip radius,maximum diameter of nacelle and location of the maximum *** to the initial nacelle,the optimized nacelle maintains a wide range of low drag and high laminar flow ratio in the disturbance space,which extends the average laminar flow region to 21.6%and facilitates a decrease of 1.98 counts in the average drag coefficient.

关键词： Adaptive surrogate model Aerodynamic robustness Multi-objective optimization Natural laminar flow nacelle Uncertain working conditions

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Topological prime

Science China(Technological Sciences) 2020年第7期63卷 1314-1322页

作者： yang XuXu yang CanHui LIU JunJie yao Xi SUO ZhiGang John A.Paulson School of Engineering and Applied Sciences Kavli Institute for Bionano Science and TechnologyHarvard UniversityCambridge MA 02138USA State Key Laboratory of Fluid Power&Mechatronic System Key Laboratory of Soft Machines and Smart Devices of Zhejiang ProvinceDepartment of Engineering Mechanics and Center for X-MechanicsZhejiang UniversityHangzhou 310027China Department of Mechanics and Aerospace Engineering Southern University of Science and TechnologyShenzhen 518055China Key Lab for Special Functional Materials of Ministry of Education Henan UniversityKaifeng 475004China

This paper describes a general method, called topological prime, to stitch functional groups to a substrate of entropic polymer network. The precursor of a topological primer contains polymers, crosslinkers, and coupling agents. When the precursor is applied on the surface of the substrate, the crosslinkers link the primer polymers into a primer network, in topological entanglement with the substrate network, while the coupling agents link the primer network to the functional groups. The use of topological prime is demonstrated by priming a hydrophobic elastomer of an arbitrary shape for hydrophilic coating. We describe an approach that fulfills two fundamental requirements: wetting and adhesion. The coated elastomer maintains hydrophilicity and lubricity after stretch, scratch, swell, and slide. As a further demonstration, a hydrogel substrate is primed for hydrophobic coating. Topological prime opens an enormous space for applications in engineering and biomedicine.

关键词： elastomer hydrogel hydrophilic coating topological prime functional groups

Graphene-based electrocatalysts for advanced energy conversion

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Green Energy & Environment 2023年第5期8卷 1265-1278页

作者： Pingping yang Xin yang Wenzhu Liu Ruike Guo Zufu yao Key Laboratory of Research and Utilization of Ethnomedicinal Plant Resources of Hunan Province Hunan Engineering Laboratory for Preparation Technology of Polyvinyl Alcohol Fiber MaterialHuaihua UniversityHuaihua418000China Hunan Provincial Key Laboratory of Dong Medicine Hunan University of MedicineHuaihua418000China

Graphene-based nanocatalysts have appealed much interest as advanced electrocatalysts toward energy conversion reactions due to their outstanding electrocatalytic performance from the distinctive chemical composites and strong synergistic *** to better understand the role of graphene played in enhancing the catalytic performance and offer guidance for fabricating more efficient graphenebased electrocatalysts,we herein summarize the remarkable achievements of graphene-based electrocatalysts for energy-conversion-related *** by discussing applications of graphene in the electrocatalytic reactions,we have manifested the crucial role of graphene played in promoting the catalytic ***,many representative graphene-based catalyst hybrids for electrocatalytic reactions are also overviewed,showing many effective strategies for the fabrication of more efficient graphene-related materials for the practical ***,the perspective insights and challenging issues are also concluded to provide directions for the future development.

关键词： Graphene Electrocatalysis Energy conversion Activity

Game-theoretical Model for Dynamic Defense Resource Allocation in Cyber-physical Power Systems Under Distributed Denial of Service Attacks

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 41-51页

作者： Bingjing Yan Pengchao yao Tao yang Boyang Zhou Qiang yang the College of Electrical Engineering Zhejiang UniversityHangzhou 310027China Zhejiang Lab Hangzhou 311100China

Electric power grids are evolving into complex cyber-physical power systems(CPPSs)that integrate advanced information and communication technologies(ICTs)but face increasing cyberspace threats and *** study considers CPPS cyberspace security under distributed denial of service(DDoS)attacks and proposes a nonzero-sum game-theoretical model with incomplete information for appropriate allocation of defense resources based on the availability of limited *** time delay is applied to quantify the expected utility as CPPSs have high time requirements and incur massive damage DDoS *** resource allocation strategies are adopted by attackers and defenders under the three cases of attack-free,failed attack,and successful attack,which lead to a corresponding consumption of resources.A multidimensional node value analysis is designed to introduce physical and cybersecurity *** experiments and numerical results demonstrate the effectiveness of the proposed model for the appropriate allocation of defense resources in CPPSs under limited resource availability.

关键词： Game theory complex cyber-physical power system(CPPS) multidimensional evaluation distributed denial of service(DDoS)attack