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Adaptive Finite Time Stabilization of Nonholonomic systems in Perturbed Chained Form

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Adaptive Finite Time Stabilization of Nonholonomic Systems i...

Compact difference approximation with consistent boundary condition

第二十四届中国控制会议

作者： Jiankui Wang~1, Yiguang Hong , Xinghuo Yu~2 1 Institute of systems science, chinese academy of sciences, beijing 100080, P.R. china 2 School of Electrical and Computer Engineering, RMIT University, Australia

＜正＞ In this paper, the finite-time stabilization problem of chained form systems with parametric uncertainties is investigated. A novel switching control strategy is proposed for adaptive finite-time control design with the help of Lyapunov-based method and time-rescaling technique. With the proposed control law, the uncertain closed-loop system under consideration is finite-time stable within a given settling time.

关键词： Finite time convergence Parameter uncertainty Adaptive control

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Progress in Natural science:Materials International 2003年第10期 10-15页

作者： FU Dexun*, MA Yanwen, LI Xinliang and LIU Mingyu(Laboratory of Nonlinear Mechanics, Institute of Mechanics, chinese academy of sciences, beijing 100080, china) Laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China

For simulating multi scale complex flow fields it should be noted that all the physical quantities we are interested in must be simulated well. With limitation of the computer resources it is preferred to use high order accurate difference schemes. Because of their high accuracy and small stencil of grid points computational fluid dynamics (CFD) workers pay more attention to compact schemes recently. For simulating the complex flow fields the treatment of boundary conditions at the far field boundary points and near far field boundary points is very important. According to authors’ experience and published results some aspects of boundary condition treatment for far field boundary are presented, and the emphasis is on treatment of boundary conditions for the upwind compact schemes. The consistent treatment of boundary conditions at the near boundary points is also discussed. At the end of the paper are given some numerical examples. The computed results with presented method are satisfactory.

关键词： complex flow fields numerical simulation boundary conditions upwind compact scheme.

Direct Current Electric Arc-Electroslag Ladle Furnace

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Journal of University of science and Technology beijing 2001年第2期8卷 98-100页

作者： Ping Wang, Jie Fu, Minsheng Sun, Xiangmao Kong, Zhimin Ma, Meilun Shi, Xingjiang Wang (Metallurgy School, University of science and Technology beijing, beijing 100083, china) (Machinery Engineering School, University of science and Technology beijing, Be Univ Sci & Technol beijing Met Sch Beijing 100083 Peoples R China Univ Sci & Technol beijing Machinery Engn Sch Beijing 100083 Peoples R China Anyang Iron & Steel Grp Co Ltd Anyang 455004 Peoples R China

In order to solve the high consumption problem of small capacity ladle furnace (LF), the operation principle and control method of the DC are and electroslag heating ladle furnace are introduced. With only one arcing electrode, the distance between the are and the wall of ladle is enlarged, and consequently the consumption of the ladle refractory is decreased. In the invention, a signal electrode is embedded in the refractory lining of the ladle, which contacts directly with the liquid steel and the ladle shell. Two graphite anode ends are submerged in the slag layer. The signal electrode is used as voltage reference during refining process. The electroslag voltage between anode end and liquid steel is applied to control the depth of anode end in the slag layer during the refining process with this ladle furnace.

关键词： ladle furnace secondary refining DC electroslag

The enhancement of astrocytic-derived monocyte chemoattractant protein-1 induced by the interaction of opiate and HIV tat in HIV-associated dementia

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Journal of Pharmaceutical Analysis 2009年第4期21卷 277-281页

作者： Xiao Han Biomedical Experimentation,School of Basic Medical sciences,Peking University Health science Center,beijing 100191,china Biomedical Experimentation School of Basic Medical Sciences Peking University Health Science Center Beijing 100191 China

HIV-associated dementia(HAD)is a public health problem and is particularly prevalent in drug *** neuropathogenesis of human immunodeficiency virus(HIV)infection involves a complex cascade of inflammatory events,including monocyte/macrophage infiltration in the brain,glial immune activation and release of neurotoxic *** these events,astrocytic-derived monocyte chemoattractant protein-1(MCP-1)plays an important role,whose release is elevated by HIV transactivator of transcription(HIV tat)and could be further elevated by *** review will also consider some critical factors and events in MCP-1 enhancement induced by the interactions of opiate and HIV tat,including the mediating role of mu opioid receptor(MOR)and CCR2 as well as the possible signal transduction pathways within the ***,it will make some future perspectives on the exact pathways,new receptors and target cells,and the vulnerability to neurodegeneration with HIV and opiates.

关键词： dementia HIV transactivator of transcription astrocyte morphine monocyte chemoattractant protein-1

Thermal stability of nanostructured NiCrC coating prepared by HVAF spraying of cryomilled powders

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Rare Metals 2008年第4期27卷 418-424页

作者： CUI Hua TAO Kai ZHOU Xianglin ZHANG Jishan School of Materials science and Engineering University of Science and Technology Beijing Beijing 100083 China State Key laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China

Thermal stability of nanostructured NiCrC coating prepared by high velocity air-fuel （HVAF） spraying of cryomilled feedstock powders was investigated. Transmission electron microscopy （TEM）, differential scanning calorimetry （DSC）, and X-ray diffraction （XRD） were utilized for characteristic analysis. Recrystallization and normal grain growth occur when isothermal treatment is performed at 923 K （0.55 TM） for up to 100 h, and the average grain size increases from initial 41 nm for as-deposited state to around 100 nm for nearly equilibrium state. Isochronal treatment at 823 K and 1023 K was also conducted for comparison. Accordingly, for 0.49 to 0.61 T/TM, the time exponent n deduced from D^1/n - D0^1/n = kt increases from 0.15 to 0.30. The observed high thermal stability is attributed primarily to a Zener pinning mechanism arising from the fine Cr2O3 dispersions and the solute drag effect as well.

关键词： nanostructure coatings grain growth heat treatment high velocity air fuel (HVAF) cryomilling

Constructing the Metabolic and regulatory Pathways in Germinating Rice Seeds through Proteomic Approach

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Constructing the Metabolic and regulatory Pathways in Germin...

SYNTHESIS OF BLOCK COPOLYMER BY INTEGRATED LIVING ANIONIC POLYMERIZATION-ATOM TRANSFER RADICAL POLYMERIZATION(ATRP)

第二届全国种子科学与技术学术研讨会

作者： Dongli He1,Chao Han1,Jialing Yao2,Shihua Shen3,Pingfang Yang1 (1 Key Laboratory of Plant Germplasm Enhancement and Speciality Agriculture,Wuhan Botanical Garden,chinese academy of sciences,Wuhan 430074 china 2 College of life science,Huazhong Agriculture University,Wuhan,china 3 The Research and Development Center for Energy Plants,Institute of Botany,chinese academy of sciences,beijing 100093,china)

Construction of metabolic and regulatory pathway from proteome can contextualize the large scale data within the overall physiological scheme of an *** is an efficient way to predict metabolic phenotype or regulatory *** did protein profiling for the germinating rice seeds through one-dimensional electrophoresis via liquid chromatography tandem mass spectrometry proteomic shotgun *** than 670 proteins were identified,and could be sorted into 14 functional *** metabolic proteins were integrated into different metabolic pathways to show the style of reserves mobilization and precursor preparation during the *** of the regulatory proteins indicated that regulation of redox homeostasis and gene expression also play important roles for the rice seed *** transcription is unnecessary,it could ensure the rapidity and uniformity for the *** with the stored mRNA is required for the *** study will help us to further understand how the rice seed initiate and regulate its germination.

关键词： germination metabolic pathway proteomics rice seed

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chinese Journal of Polymer science 2000年第1期18卷 39-43页

作者： Bing Liu Feng Liu Ning Luo Sheng-kang Ying Qing Liu Laboratory of Living Polymerization, East china University of science and Technology, Shanghai 200237, china Research Institute of beijing Yanshan Petrochemical Corporation, beijing 102549, china E china Univ Sci & Technol Lab Living Polymerizat Shanghai 200237 Peoples R China beijing Yanshan Petrochem Corp Res Inst Beijing 102549 Peoples R China

Alpha-trichloroacetoxy terminated polystyrene oligomer (PS-CH2CH2OCOCCl3) and poly-(styrene-b-butadiene) oligomer [P(S-b-B)-CH2CH2OCOCCl3)] were synthesized by living anionic polymeri-zation using n-butyllithium as initiator. Then the PS-CH2CH2OCOCCl3 (PS-Cl-3) or P(S-b-B)-CH2CH2O-COCCl3 (PSB-Cl-3) was used as the macroinitiator in the polymerization of(meth)acrylates in the presence of CuX/bpy. AB diblock and ABC triblock copolymers were prepared by the integrated living anionic polymerization (LAP)-atom transfer radical polymerization (ATRP). The structures of the PSB-Cl-3 and the P(S-b-MMA) were identified by FTIR and H-1-NMR spectrum, respectively. A new way to design block copolymers (the combination of LAP and ATRP) was developed.

关键词： living anionic polymerization atom transfer radical polymerization block copolymer

The empirical likelihood goodness-of-fit test for regression model

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science china mathematics 2007年第6期50卷 829-840页

作者： Li-xing ZHU, Yong-song QIN & Wang-li XU Department of mathematics, Hong Kong Baptist University, Kowloon Tong, Hong Kong, china School of Mathematical sciences, Guangxi Normal Uinversity, Guilin 541004, china School of Statistics, Renmin University of china, beijing 100875, china Department of mathematics Hong Kong Baptist University Kowloon Tong Hong Kong China School of Mathematical sciences Guangxi Normal Uinversity Guilin 541004 China School of Statistics Renmin University of China Beijing 100875 China

Goodness-of-fit test for regression modes has received much attention in literature. In this paper, empirical likelihood (EL) goodness-of-fit tests for regression models including classical parametric and autoregressive (AR) time series models are proposed. Unlike the existing locally smoothing and globally smoothing methodologies, the new method has the advantage that the tests are self-scale invariant and that the asymptotic null distribution is chi-squared. Simulations are carried out to illustrate the methodology.

关键词： regression model AR time series models empirical likelihood asymptotic normality goodness-of-fit 62G05 62G20 62G30

Chemical and Strontium Isotopic Compositions of the Hanjiang Basin Rivers in china:Anthropogenic Impacts and Chemical Weathering

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Chemical and Strontium Isotopic Compositions of the Hanjiang...