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A novel posture alignment system for aircraft wing assembly

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第11期10卷 1624-1630页

作者： bin ZHANG bao-guo YAO Ying-lin KE College of Mechanical and Energy Engineering Zhejiang University Hangzhou 310027 China

A novel 6-degree of freedom (DOF) posture alignment system, based on 3-DOF positioners, is presented for the assembly of aircraft wings. Each positioner is connected with the wing through a rotational and adsorptive half-ball shaped end-effector, and the positioners together with the wing are considered as a 3-PPPS (P denotes a prismatic joint and S denotes a spherical joint) redundantly actuated parallel mechanism. The kinematic model of this system is established and a trajectory planning method is introduced. A complete analysis of inverse dynamics is carried out with the Newton-Euler algorithm, which is used to find the desired actuating torque in the design and path planning phase. Simulation analysis of the displacement and actuating torque of each joint of the positioners based on inverse kinematics and dynamics is conducted, and the results show that the system is feasible for the posture alignment of aircraft wings.

关键词： Aircraft wings Three-coordinate positioner Posture alignment Kinematics Dynamics

SYNTHESIS AND CHARACTERIZATION OF FUNCTIONALIZED CARBON BLACK/POLY(VINYL ALCOHOL) HIGH REFRACTIVE INDEX NANOCOMPOSITES

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Chinese Journal of Polymer Science 2012年第5期30卷 652-663页

作者： Peng-fei Xue Ji-bin Wang Yu-bin bao 李秋影 Chi-fei Wu Polymer Alloy Laboratory and Key Laboratory of Ultrafine Materials of Ministry of Education East China University of Science and TechnologyShanghai200237China Shanghai Key Laboratory Polymeric Materials East China University of Science and TechnologyShanghai200237China

Carbon black （CB）/polymer composites with high refractive index （RI） were fabricated from poly（vinyl alcohol）（PVA） and covalently functionalized nano-CB （PVA-es-CB） by simple esterification reaction. Transmission electron microscopy showed that tmifonn aggregates of PVA-es-CB nanoparticles with a size smaller than I00 nm formed in the nanocomposite films. Ellipsometric measurements indicated that the PVA-es-CB/PVA composite films had a RI in the range 1.520-1.598 linearly increased with the PVA-es-CB volume content. Theoretical equation based on Lorentz-Lorenz theory provided reasonably close estimation of the refractive indices to the experimentally observed values. The hybrid films also revealed relatively good surface planarity, thermal stability and optical transparency.

关键词： High refractive index Carbon black Poly(vinyl alcohol) Nanocomposite.

Malicious Synchrophasor Detection Based on Highly Imbalanced Historical Operational Data

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CSEE Journal of Power and Energy Systems 2019年第1期5卷 11-20页

作者： Jingyu Wang Zhengwei Sun bin bao Dongyuan Shi State Key Laboratory of Advanced Electromagnetic Engineering and Technology School of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074China Northeast Branch of State Grid Corporation of China Shenyang 110180China

By maliciously manipulating the synchrophasors produced by phasor measurement units in power systems,cyber attackers can mislead the control center into taking wrong *** the viewpoint of machine learning,normal and malicious synchrophasors may exhibit different spatial distribution characteristics when mapped into a latent ***,a malicious synchrophasor detector can be acquired by training a classification model with instances derived from historical operational synchrophasor ***,malicious synchrophasors occur infrequently in *** is likely to incur a great deal of effort and may even introduce inevitable experience errors when extracting and labeling a sufficient number of malicious synchrophasors from historical operational data for *** most existing detectors,if they are directly trained with highly imbalanced datasets,their performances may severely *** this paper,a novel type of malicious synchrophasor detector is developed based on a combinatorial use of data rebalancing,Bagging-based ensemble learning,and the widely recognized eXtreme Gradient Boosting(XGBoost)*** show that although fewer malicious instances are provided,the proposed detector is still capable of detecting malicious synchrophasors.

关键词： Data rebalancing ensemble learning malicious synchrophasor detection XGBoost

Influences of Iridium and Palladium on Oxidation Resistance of PtAl Coating

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Acta Metallurgica Sinica(English Letters) 2021年第8期34卷 1120-1130页

作者： Ling-Yi Qian Jing Wang Yun-Shan Guo He Liu Ze-bin bao AECC Commercial Aircraft Engine Co. LtdShanghai 201108China Shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China

The overarching goal of present study is to investigate the effects of Ir and Pd additions on the oxidation behaviour of PtAl coatings. Prior to depositing standard PtAl coating, Ir layer was electroplated by IrBr 3 aqueous solution while Pd layer was prepared using electroless deposition. Comparing with normal PtAl coating, cyclic oxidation tests were carried out on both the Ir-and Pd-modified aluminide coatings. The results showed that Ir-modified PtAl coating exhibited better oxidation resistance than both Pd-modified and normal PtAl coatings because Ir partly served as diffusion barrier to reserve Al while Pd did not.

关键词： Thermal barrier coating PtAl coating Oxidation resistance Iridium Palladium

Correlativity between coal permeability and strain in quasi-plane strain state

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Journal of Coal Science & Engineering(China) 2013年第4期19卷 493-499页

作者： bao-bin GAO Yun-Peng LIU Stage Key Laboratory Cultivation Base for Gas Geology and Gas Control (Henan Polytechnic University) Jiaozuo 454000 China Opening Project of Key Laboratory of Deep Mine Construction Henan Polytechnic University Jiaozuo 454000 China School of Safety Science and Engineering Henan Polytechnic University Jiaozuo 454000 China

To simulate the variety of big coal sample permeability during the rupture process under quasi-plane strain state, a series of experiments have been performed by a set of self-made coal-gas coupling test system. The test results indicate that the development trend between the permeability rate-strain curve and the stress-strain curve of big coal sample is almost consistent. The permeability rate-strain curve is general hysteretic to stress-strain curve, indicating the close relativity between the evolvement of damage and the development of permeability rate. However, there is time interval between them and the perme- ability rate peaks value when the sample reaches the softened stage after the peak stress. Based on the characteristics of per- meability rate-strain curve, three stages were plotted out： the stage before minimum permeability rate （/co）, the stage between minimum and maximum of permeability rate and the stage after the maximum permeability rate （kmax）. According to the three stages of permeability rate, the segmental curve equations of permeability rate-strain were fitted： the first stage can be fitted with negative exponential function; the second stage can be fitted with Boltzmann equation; and the last stage can be fitted with multinomial equation.

关键词： permeability quasi-plane strain coal-gas coupling test system stress-strain

Thermal cycling behavior of nanostructured and conventional yttria-stabilized zirconia thermal barrier coatings via air plasma spray

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Rare Metals 2023年第11期42卷 3859-3869页

作者： Cheng-Yang Jiang Min Feng Chun-Tang Yu Ze-bin bao Sheng-Long Zhu Fu-Hui Wang Shenyang National Laboratory for Materials Science Northeastern UniversityShenyang110819China Institute of Metal Research Chinese Academy of SciencesShenyang110016China

Two thermal barrier coating(TBC)systems comprising NiCoCrAlY bond coat onto a second-generation Ni-based single crystal superalloy and nano structured4 mol%Y_(2)O_(3)-stabilized ZrO_(2)(4YSZ)and conventional yttria-stabilized zirconia(YSZ)top coats upwardly were deposited by approaches of arc ion plating(AIP)and air plasma spray(APS).As indicted by the experimental results,the 4YSZ TBCs exhibited superior thermal cycling resistance compared with conventional YSZ TBCs at 1100℃.The 4YSZ top coat exhibited higher toughness due to its intrinsic property of nanocrystalline structure,homogeneously distributed and diverse directions of pores and preexisted *** cracks and spallation in 4YSZ TBCs occurred at the interface of top coat and thermally grown oxide(TGO)***,the crack initiation and propagation started along the lamellar interface in the top coat of conventional YSZ TBCs,leading to the rapid crack bridging and subsequent spalling of top ***,before and after oxidation,the 4YSZ top coat showed higher hardness compared to conventional YSZ top *** mechanism and distribution of residual stress in TGO for the 4YSZ TBCs were investigated in the current study.

关键词： TBC Nanocrystalline TGO Thermal cycling Toughness

First Observation of Neoclassical Tearing Modes in the HL-2A Tokamak

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Chinese Physics Letters 2010年第6期27卷 137-140页

作者： JI Xiao-Quan YANG Qing-Wei LIU Yi ZHOU Jun FENG Bei-bin YUAN bao-Shan Southwestern Institute of Physics Chengdu 610041

The m/n = 2/1 neoclassical tearing modes are first observed in HL-2A low density, low beta plasma with central electron cyclotron resonance heating. The neoclassical tearing modes （NTMs） are triggered by a sawtooth crash with m/n = 1/1 precursors, which are toroidal coupled with a small scale m/n = 2/1 mode. The time history of the island width is compared with the prediction of the NTM theory, showing a good agreement between theory and experiment.

关键词： OBSERVATION (Scientific method) TOKAMAKS PLASMA (Ionized gases) ELECTRON cyclotron resonance sources HEATING MAGNETIC fields PREDICTION models

Identification and Fibrinolytic Evaluation of an Isoindolone Derivative Isolated from a Rare Marine Fungus Stachybotrys Iongispora FG216

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Chinese Journal of Chemistry 2015年第9期33卷 1089-1095页

作者： Ge Wang Wenhui Wu Quangang Zhu Shiqing Fu Xiaoyu Wang Shaotong Hong Ruihua Guo bin bao College of Food Science and Technology Shanghai Ocean University Shanghai 201306 China Institute of Marine Science Shanghai Ocean University Shanghai 201306 China Department of Chinese Pharmacy Yueyang Hospital of Integrated Chinese and Western Medicine Shanghai University of Traditional Chinese Medicine Shanghai 200437 China Shanghai Engineering Research Center of Aquatic-Product Processing andPreservation Shanghai 201306 China

An isoindolone derivative, Fungi fibrinolytic compound （R）-2,5-bis（（2R,3R）-2-（（E）-4,8-dimethylnona-3,7-dien- 1-y1）-3,5-dihydroxy-2-methy--7-oxo-3,4,7,9-tetrahydr pyrano[2,3-e]isoindol-8（2H）-yl）pentanoic acid （FGFC1, Fungi fibrinolytic compound 1）, was isolated from a rare marine microorganism strain Stachybotrys longispora FG216. The structure of FGFC1 was elucidated by 1H NMR, 13C NMR, IR, and MS data; moreover, it was also evaluated for fibrinolytic activity in vitro and in vivo. The results showed that 0.1--0.4 mmol/L of FGFC1 could stimulate generation of plasmin activity （increased by 2.05--11.44 folds） by measuring Glu-plasminogen and Lys-plasminogen activation in vitro. The experiment of fluorescein isothiocyanate （FITC）-fibrinogen degradation indicated that the effect of FGFCI on fibrinolytic activity was mediated by plasminogen and scuPA. In addition, FGFC 1 （10 mg/kg） could dissolve most of pulmonary thrombus of Wistar rat in vivo. It is possible that FGFC 1 is a potential thrombolytic agent in the future.

关键词： Stachybotrys longispora FG216 marine microorganism plasmin activity fibrinolytic activity

Oxidation Performance and Interdiffusion Behavior of a Pt-Modified Aluminide Coating with Pre-deposition of Ni

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Acta Metallurgica Sinica(English Letters) 2019年第12期32卷 1490-1500页

作者： He Liu Shuai Li Cheng-Yang Jiang Chun-Tang Yu Ze-bin bao Sheng-Long Zhu Fu-Hui Wang Institute of Metal Research Chinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Shenyang National Laboratory for Materials Science Northeastern UniversityShenyang 110819China

To refrain the interdiffusion of elements while holding good oxidation resistance,a(Ni,Pt)Al/Ni composite coating was prepared by sequential treatments of electroplating Ni and Pt and successive gaseous *** comparison with normal(Ni,Pt)Al coating,high-temperature performance of the composite coating was evaluated in isothermal oxidation test at 1100℃.Both the two coatings exhibited good resistance against high-temperature oxidation,but the interdiffusion of elements between composite coating and single-crystal(SC)superalloy substrate was greatly relieved,in which the thickness of secondary reaction zone(SRZ)and the amount of precipitated topologically close-packed phase in the SC alloy matrix were significantly *** responsible for delaying rate of coating degradation and SRZ growth/propagation are discussed.

关键词： Aluminide coating Oxidation Interdiffusion Microstructure