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Direct adaptive actuator failure compensation control:a tutorial

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Journal of Control and Decision 2014年第1期1卷 75-101页

作者： gang tao Department of Electrical and Computer Engineering University of VirginiaCharlottesvilleVAUSA College of Automation Engineering Nanjing University of Aeronautics and AstronauticsNanjingChina

A resilient control system is expected to have the capacity to restore the desired system stability and tracking performance in the presence of uncertain system faults such as actuator *** redundant actuators are used for actuator failure accommodation,uncertain actuator failures,whose failure time,pattern,and values may be unknown,can bring new challenges to feedback control design as such uncertain failures can introduce large structural,parametric,and actuation *** technical issues are associated with using redundant actuators:how redundant actuators should be coordinated for effective failure compensation control,and how a feedback control law should be adaptively designed to compensate uncertain actuator *** this paper,we present a tutorial on direct adaptive failure compensation-based solutions to these issues for different types of control systems:state tracking using state feedback,output tracking using state feedback or output feedback,for linear,non-linear,and multi-input multi-output *** give an overview on such adaptive actuator failure compensation designs which have special capacities to effectively use actuation redundancy to handle uncertain actuator failures,using either direct or indirect adaptive control approaches for direct adaptive actuator failure compensation without explicit failure detection,for fast and effective failure accommodation.

关键词： actuator failure adaptive compensation resilient control stability tracking

A parameter estimation based adaptive actuator failure compensation control scheme

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Journal of Systems Engineering and Electronics 2011年第1期22卷 1-11页

作者： gang tao Ruiyun Qi Chang Tan Depamnent of Electrical and Computer Engineering University of Virginia Charlottesville VA 22904 USA College of Automation Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 E R. China

An adaptive actuator failure compensation control scheme is developed using an indirect adaptive control method,by calculating the controller parameters from adaptive estimates of system parameters and actuator failure parameters.A key technical issue is how to deal with the actuator failure uncertainties such as failure pattern,time and values.A complete parametrization covering all possible failures is used to solve this issue for adaptive parameter estimation.A simultaneous mapping from the estimated system/failure parameters to the controller parameters is employed to make the control system capable of ensuring the desired system performance under failures,which is verified by simulation results.

关键词： actuator failure compensation adaptive control failure pattern and values parameter estimation stability and tracking uncertainty parametrization.

Adaptive actuator failure compensation and disturbance rejection scheme for spacecraft

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Journal of Systems Engineering and Electronics 2014年第4期25卷 648-659页

作者： Xuelian Yao gang tao Ruiyun Qi College of Automation Engineering Nanjing University of Aeronautics and Astronautics Department of Electrical and Computer Engineering University of Virginia

An adaptive actuator failure compensation scheme is proposed for attitude tracking control of spacecraft with unknown disturbances and uncertain actuator failures. A new feature of this adaptive control scheme is the adaptation of the failure pattern parameter estimates, as well as the failure signal parameter estimates, for direct adaptive actuator failure compensation. Based on an adaptive backstepping control design, the estimates of the disturbance parameters are used to solve the disturbance rejection problem. The unknown disturbances are compensated completely with the stability of the whole closed-loop system. The scheme is not only able to accommodate uncertain actuator failures, but also robust against unknown external disturbances. Simulation results verify the desired adaptive actuator failure compensation performance.

关键词： actuator failure compensation adaptive control failurepattern disturbance estimation spacecraft stability and tracking.

AN ASYMPTOTIC SOLUTION OF VELOCITY FIELD IN SHIP WAVES

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Journal of Hydrodynamics 2006年第4期18卷 387-392页

作者： WU Yun-gang tao Ming-de Department of Mechanics and Engineering Science and The Key Laboratory of Wave Scattering and RemoteSensing Information Fudan University Shanghai 200433 China

The stationary phase method in conventional Lighthill＇s two-stage scheme to get the expressions of the velocity field was given up in this paper. The method that Ursell had used in deducing the elevation expression of ship wave was adopted, and an asymptotic solution of velocity field of ship waves on an inviscid fluid that is perfectly fit for the region inside and outside the critical lines was obtained. It is very convenient to be used in SAR technique.

关键词： ship waves velocity field remote sensing,asymptotic solution

Microwave-assisted synthesis of diaryl or aryl-alkyl sulfones without catalyst

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Chinese Chemical Letters 2009年第1期20卷 17-20页

作者： Jiong Zou Feng Li Feng gang tao Department of Chemistry Fudan University Shanghai 200433 China

The microwave-assisted coupling reaction of electrondeficient aryl halides with sulfinic acid salts through SNAr-based addition reactions within 5-30 min. No catalysts were required under our conditions.

关键词： Microwave Sulfone SNAr-based addition reaction

Transgenic Tobacco Expressing a Modified VP6 Gene Protects Mice Against Rotavirus Infection

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Journal of Integrative Plant Biology 2005年第8期47卷 978-987页

作者： Jiang-Li DONG Bo ZHOU gang SHENG tao WANG State Key Laboratory of Agrobiotechnology China Agricultural University Beijing 100094 China

Elevated expression of the rotavirus VP6 antigen in transgenic plants is a critical factor in the development of a safe and effective rotavirus vaccine. Using codon optimization, a gene that encodes the inner capsid protein VP6 of the human group A rotavirus was synthesized （sVP6）. The VP6 and sVp6 genes were transformed into tobacco （Nicotiana tabacum L.） plants using Agrobacterium tumefaciens. The expression level of the sVP6 gene in transgenic plants was 3.8-34-fold higher than that of controls containing the non-modified VP6 gene, accounting for up to 0.34% of the total soluble protein （TSP）. Then, BALB/ c female mice that had been gavaged weekly with 10 mg TSP containing 34 p.g VP6 protein, in which VP6-specific serum IgG and mucosal IgA antibodies were investigated. The severity and duration of diarrhea caused by simian rotavirus SA-11 challenge were reduced significantly in passively immunized pups, which indicates that anti-VP6 antibodies generated in orally immunized female mice can be passed onto pups and provide heterotypic protection. An edible vaccine based on the VP6 of human rotavirus group A could provide a means to protect children and young animals from severe acute diarrhea.

关键词： capsid protein VP6 edible vaccine oral immunogenicity rotavirus tobacco transgenic plants.

Ultrastructure and phylogeny of Ustilago coicis

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2013年第4期14卷 336-345页

作者： Jing-ze ZHANG Pei-gang GUAN gang tao Mohammad Reza OJAGHIAN Kevin David HYDE Institute of Biotechnology College of Agriculture and BiotechnologyZhejiang University Guizhou Institute of Plant Protection Key Laboratory of Systematic Mycology and Lichenology Institute of MicrobiologyChinese Academy of Sciences Institutue of Excellence in Fungal Research School of ScienceMae Fah Luang University

Ustilago coicis causes serious smut on Coix lacryma-jobi in Dayang Town,Jinyun County,Zhejiang Province of *** this paper,ultrastructural assessments on fungus-host interactions and teliospore development are presented,and molecular phylogenetic analyses have been done to elucidate the phylogenetic placement of the *** growth within infected tissues was both intracellular and intercellular and on the surface of fungus-host interaction,and the fungal cell wall and the invaginated host plasma membrane were separated by a sheath comprising two distinct layers between the fungal cell wall and the invaginated host plasma *** development of teliospore walls was unique as they appeared to be originated from the *** addition,internal transcribed spacer(ITS) and large subunit(LSU) sequence data showed that *** is closely related to Ustilago trichophora which infects grass species of the genus Echinochloa(Poaceae).

关键词： Fungus-host interaction Molecular phylogenetics Smut Teliospore wall development

Lumped parameter model for resonant frequency estimation of a thermoacoustic engine with gas-liquid coupling oscillation

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第3期12卷 232-237页

作者： Ke TANG Tian LEI Xiao-gang LIN tao JIN Yu ZHANG Institute of Refrigeration and Cryogenics Zhejiang University Hangzhou 310027 China

Gas-liquid coupling oscillation is a novel approach to reducing the resonant frequency and to elevating the pressure amplitude of a thermoacoustic *** a thermoacoustic engine is used to drive low-frequency pulse tube refrigerators,the frequency matching between the thermoacoustic engine and the refrigerator plays an important *** on an acoustic-electric analogy,a lumped parameter model is proposed to estimate the resonant frequency of a standing-wave thermoacoustic engine with gas-liquid coupling ***,a simplified lumped parameter model is also developed to reduce the computation *** resonant frequency dependence on the mean pressure,the gas space volume,and the water column length is computed and *** impact of different working gases on the resonant frequency is also *** effectiveness of the models is validated by comparing the computed results with the experimental data of the gas-liquid coupling oscillation *** increase in the mean working pressure can lead to a rise in the resonant frequency,and a lower resonant frequency can be achieved by elongating the liquid *** comparison with nitrogen and argon,carbon dioxide can realize a lower frequency due to a smaller specific heat ratio.

关键词： Thermoacoustic engine Gas-liquid coupling oscillation Acoustic-electric analogy Resonant frequency

System Characterization and Adaptive Tracking Control of Quadrotors under Multiple Operating Conditions

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Guidance, Navigation and Control 2021年第2期1卷 1-39页

作者： Yu Sheng gang tao Department of Electrical and Computer Engineering University of Virginia CharlottesvilleVA 22904USA

This paper presents an adaptive controller design framework with input compensation for quadrotor systems,which deals with di®erent system operating conditions with a uniform update law for the controller *** motivation of the work is to handle the situation that existing adaptive control schemes are either restricted to the system equilibrium as the hover condition or unable to deal with the diverse system uncertainties which cause system interactor matrix and high-frequency gain matrix to *** adaptive control scheme equipped with an input compensator is constructed to make the system to have a uniform interactor matrix and a consistent pattern of the gain matrix signs over di®erent operating conditions,which are key prior design conditions for model reference adaptive control applied to quadrotor *** deal with the uncertain system high-frequency gain matrix,a gain matrix decomposition technique is employed to parametrize an error system model in terms of the gain parameters and tracking errors,for the design of an adaptive parameter update law with reduced system *** is ensured that all closed-loop system signals are bounded,and the system output tracks a reference output asymptotically despite the system parameter uncer-tainties and the uncertain o®sets at non-equilibrium operating *** proposed scheme expands the capacity of adaptive control for quadrotors to operate at multiple operating con-ditions in the presence of system *** results of a quadrotor with the proposed adaptive control scheme are presented to show the desired system performance.

关键词： Adaptive control quadrotors system uncertainties