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Robust H-infinity fuzzy control for uncertain Markovian jump nonlinear singular systems with wiener process

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控制理论与应用（英文版） 2010年第2期8卷 205-210页

作者： Aiqing ZHANG 1 , Huajing FANG 2.(1.college of Mathematics and Computer Science, Jianghan University, Wuhan Hubei 430056, china {2. of Control Science and Engineering, Huazhong University of Science and Technology, Wuhan Hubei 430074, china) college of Mathematics and Computer Science Jianghan University Wuhan Hubei China department of Control Science and Engineering Huazhong University of Science and Technology Wuhan Hubei China

This paper deals with the problems of robust stochastic stabilization and H-infinity control for Markovian jump nonlinear singular systems with Wiener process via a fuzzy-control approach. The Takagi-Sugeno (T-S) fuzzy model is employed to represent a nonlinear singular system. The purpose of the robust stochastic stabilization problem is to design a state feedback fuzzy controller such that the closed-loop fuzzy system is robustly stochastically stable for all admissible uncertainties. In the robust H-infinity control problem, in addition to the stochastic stability requirement, a prescribed performance is required to be achieved. Linear matrix inequality (LMI) sufficient conditions are developed to solve these problems, respectively. The expressions of desired state feedback fuzzy controllers are given. Finally, a numerical simulation is given to illustrate the effectiveness of the proposed method.

关键词： Fuzzy control H-infinity control Singular systems Stochastic stability Linear matrix inequality (LMI)

Utilization of a spiropyran derivative in a polymeric film optode for selective fluorescent sensing of zinc ion

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Science china Chemistry 2006年第3期49卷 246-255页

作者： ZHANG Ying1, SHAO Na1, YANG Ronghua1, LI Ke’an1, LIU Feng1, CHAN Winghong2.& MO Tian2.1. college of Chemistry and Molecular Engineering, Peking University, Beijing 100871, china 2. {2. of Chemistry, Hong Kong Baptist University, Hong Kong, china 1. college of Chemistry and Molecular Engineering Peking University Beijing 100871 China 2. department of Chemistry Hong Kong Baptist University Hong Kong China

A new spiropyran derivative was synthesized and first utilized in a polymericfilm-based optical sensor for zinc ion. Spiropyrans, combining the characteristics of metal bindingand signal transduction, show potential function in the design of optical chemical sensors(optodes) toward metal ions. When embedded in a plasticized poly (vinyl chloride) (PVC) membrane,the newly synthesized spiropyran derivative 1 exhibits obvious fluorescence enhancement at 630 nm inthe presence of zinc ion in aqueous solution. With the optimum condition described, the optodemembrane responds to zinc ion over a dynamic range of 4.94x10^(-7) to 4.15x10^(-4)mol·L^(-1), witha detection limit of 1.51x10^(-7) mol·L^(-1). The membrane not only displays excellentphotostability, reproducibility and reversibility, but also exhibits high selectivity toward zincion over transition metal ions including Hg^(2.), Cd^(2.), Pb^(2.), Cu^(2.), Fe^(3+) and commoncationic ions presented in the physiological fluids.

关键词： spiropyran, sensor, PVC membrane, zinc ion, fluorescent spectroscopy.

Reducing sympathetic nervous tone in aged rats bettered cardiomyocyte contraction by improving the response of β_2.adrenoceptor

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中国病理生理杂志 2010年第A10期26卷 2044-2045页

作者： Wang Ying1,Zhao Zhi2.Hao Yan-ling2.Xu Chuan-ying2.Sun Yi-wei2.Sun Hong2.1department of Pathophysiology,2.0} of physiology,XuZhou medical college,Xuzhou2.1002.china)

The study was to investigate the effect of reducing central sympathetic nervous tone with clonidine on cardiomyocyte contraction,and further to analyze the influence of reducing the central sympathetic nervous tone on response of β1 and β2.AR in aged ventricular ***-Dawley rats were randomly divided into three groups:adult group,aged group and aged group with clonidine.

关键词： sympathetic adrenoceptor contraction cytes shortening antagonist pretreatment reduc evident clearly

Microwave peak absorption frequency of liquid

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Science china(Physics,Mechanics & Astronomy) 2008年第9期51卷 1254-1263页

作者： HAN GuangZe1 & CHEN MingDong2.1 department of Physics,South china University of Technology,Guangzhou 510640,{2. 2.Guangzhou Auto college,South china University of Technology,Guangzhou 510800,{2. 1. department of Physics South China University of Technology Guangzhou 510640 China 2. Guangzhou Auto college South China University of Technology Guangzhou 510800 China

Microwave-assisted extraction is a new effective method which has practical ap-plications in many fields. Microwave heating is one of its physical mechanisms,and it also has the characteristic of selectivity. When the applied microwave fre-quency equals a certain absorption frequency of the material (or specific compo-nent),the material will intensively absorb microwave energy. This is also known as resonant absorption,and the frequency is called the peak absorption frequency which depends on the physical structure of the material. In this work,dynamic hy-drogen bond energy was included in molecular activation energy; with the liquid cell model,the expression of interaction energy between dipolar molecules was derived. The rotational relaxation time was gotten from the Eyring viscosity formula. Then based on the relationship between dielectric dissipation coefficient and re-laxation time,the expression of microwave peak absorption frequency as a func-tion of the material physical structure,rotational inertia and electrical dipole mo-ment of molecules was established. These theoretical formulas were applied to water and benzene,and the calculated results agree fairly well with the experi-mental data. This work can not only deepen the study of the interaction between microwave and material,but also provide a possible guide for the experiment of microwave-assisted extraction.

关键词： microwave-assisted extraction microwave heating relaxation time liquid viscosity peak absorption fre-quency

Threshold Signature Scheme Based on Discrete Logarithm and Quadratic Residue

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Wuhan University Journal of Natural Sciences 2004年第5期9卷 770-774页

作者： FEI Ru-chun 1,2., WANG Li-na 1 1.School of Computer, Wuhan University, Wuhan 430072. Hubei, china 2.department of Information Engineering, Benxi {2. of Metallurgy, Benxi 11702.,Liaoning,china Wuhan University School of Computer Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) Benxi college of Metallurgy Department of Information Engineering Benxi Liaoning China (GRID:grid.49470.3e) Wuhan University School of Computer Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***)

Digital signature scheme is a very important research field in computer security and modern cryptography. A (k, n) threshold digital signature scheme is proposed by integrating digital signature scheme with Shamir secret sharing scheme. It can realize group-oriented digital signature, and its security is based on the difficulty in computing discrete logarithm and quadratic residue on some special conditions. In this scheme, effective digital signature can not be generated by anyk?1 or fewer legal users, or only by signature executive. In addition, this scheme can identify any legal user who presents incorrect partial digital signature to disrupt correct signature, or any illegal user who forges digital signature. A method of extending this scheme to an Abelian group such as elliptical curve group is also discussed. The extended scheme can provide rapider computing speed and stronger security in the case of using shorter key. Key words threshold scheme - digital signature - discrete logarithm - quadratic residuc - threshold digital signature CLC number TP 309. 7 Foundation item: Supported the National Nature Science Foundation of china, Hubei Province (90104005, 2.02.AB0039)Biography: FEI Ru-chun (1964-), male, Ph. D candidate, Associated professor, research direction: information security and cryptography.

关键词： threshold scheme digital signature discrete logarithm quadratic residuc threshold digital signature

A New Bianthraqinonc Glycoside from Eremurus chinensis

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Chinese Chemical Letters 2000年第2期11卷 135-138页

作者： Jian Gong SHI1 Chong LI2.Ying Peng ZHANG2.Cheng Zhong ZHANG2.(1Institute of Materia Medica, Chinese Academy of medical Sciences and Peking Union medical, {2., Beijing, 100050 2.3} of Pharmacy, Lanzhou medical {2., Lanzhou 730000) Institute of Materia Medica Chinese Academy of Medical Sciences Peking Union Medical College Beijing 100050 China department of Pharmacy Lanzhou Medical College Lanzhou 730000 China

A new bianthraquinone glycoside, 8-O-β-D-glucopyranosyl-2.7'-bi(1,8-dihydroxy-3- methyl-9, 10-anthraquinonyl)1 was isolated from Eremurus chinensis Fedtch. Its structure was established by spectroscopic techniques in... 详细信息

关键词： Eremurus chinensis Liliaceae bianthraquinone glycoside.

Effects of NaNbO_3-Co_2._3 Co-additive on the Properties of PZN-PZT Ceramics

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Journal of Wuhan University of Technology(Materials Science) 2007年第4期22卷 722-724页

作者：邓毅华 college of Material Science and Engineering South China University of Technology department of Electronic Science and Technology Huazhong University of Science and TechnologyWuhan 430074China

NaNbO3-Co2.3 co-added PZN-PZT （PZCNNT） ceramics were prepared using conventional solid state reaction. The piezoelectric and dielectric properties were measured. The experimental results show that the addition of 0.3mo1% Co2.3 leads to low dielectric loss （tgδ） in PZCNNT ceramics and the proper addition of NaNbO3 not only improves piezoelectric properties but also decreases intensively dielectric loss and mechanical loss. The optimal ceramic having d33=310 pC/N, kp=0.59, εr=985, tgδ=0.0034, Qm=1380 was obtained.

关键词： PZN-PZT piezoelectric constant dielectric constant dielectric loss

Coupling analysis of unsteady seepage and stress fields in discrete fractures network of rock mass in dam foundation

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Science china(Technological Sciences) 2011年第S1期54卷 133-139页

作者： CHAI JunRui 1,2.& XU WeiSheng 2.1 college of Hydraulic and Environmental Engineering,china Three Gorges University,Yichang 443002.china 2.college of Hydropower Engineering,Xi’an University of Technology,Xi’an 710048,china 1. college of Hydraulic and Environmental Engineering China Three Gorges University Yichang 443002 China2. College of Hydropower Engineering Xi’an University of Technology Xi’an 710048 China

The drag force of water flow through single fracture and the coupling characteristics of seepage and stress in single fracture surface are analyzed,and a three dimensional model of coupled unsteady seepage and stress fields is *** model is used to the analysis of foundation rock mass of a high *** the coupling effects are considered,the changes of boundary heads have less influence on the inner head of rock mass,and the strong permeability of main fractures *** the coupling effects are not considered,the fractures distribution affects the inner head more *** the upstream water head declines,the inner head of dam foundation slightly declines and the hydraulic gradient distribution becomes smoother.A bigger upstream water level declining velocity has a stronger lag effect,meanwhile the values of stress components change more *** the upstream water level declining velocity directly affects the stability of rock mass in dam foundation and we should take into account the above factors to make sure the safety of the dam during reservoir level fluctuation period.

关键词： hydraulic engineering unsteady seepage stress coupling fractures network rock mass

Ability of Agrogyron elongatum to accumulate the single metal of cadmium, copper, nickel and lead and root exudation of organic acids

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Journal of Environmental Sciences 2001年第3期13卷 368-375页

作者： YANG Hong 1, Jongathan W.C.Wong 2. YANG Zhi min\+1, ZHOU Li xiang 1(1. college of Science, Nanjing Agricultural University, Nanjing\ 2.0095, china. 2. {2. of Biology, Hong Kong Baptist University, china) college of Science Nanjing Agricultural University Nanjing 210095 China.

Agrogyron elongatum were grown in nutrient solution containing moderate to high amounts of separate heavy metal of Cd, Cu, Ni and Ph in a greenhouse for a 9 - day. Cd, Cu, Ni and Ph generally led to decrease in the elongation of roots although the length of seedlings exposed to Cd and Ph at 0.05 and 0.5 mg/L showed to be slightly greater than that of controls. Of the four metals in the experiment, Ph was absorbed and accumulated to the highest level, with the concentrations of 92.54 mg/kg dry weight (DW) in roots and 11683 mg/kg DW in shoots. Cd was moderately accumulated in Agrogyron elongatum, but the maximum bioaccumulation coefficients (BCs) for roots and shoots were observed. The patterns for Cu and Ni uptake and distribution in plants differed from those of Ph and Cd, as it was showed that the shoot accumulation of Cu and Ni was significantly higher than in roots. A. elongation had the highest Ni concentration in shoots (302.1 mg/kg DW) at the external concentration of 2.0 mg/L. Cu ranked second, with a shoot concentration of 12.30 mg/kg DW when 50 mg/L Cu in solution was applied. For the four trace elements tested, the highest concentrations in shoots decreased by the order of Ni > Cu > Ph > Cd (mg/kg DW), and those in roots were Ph > Cd > Ni > Cu (mg/kg DW). Malic, oxalic and citric acids exuded by roots exposed to 1 and 50 mg/L of the metals were detected. Release of organic acids from plants significantly differed among the metal treatments. Cu was most effectively in inducing root exudation of the three types of organic acids. Cd, and Ni were also the inducers of secretion of malic and oxalic acids. With reference of Pb, a small amounts of malic and oxalic acids were detected in the root exudates, but few quantities, of citric acid were. found. However, no correlation between alternations in root exudation of organic acids and metal accumulation could be established.

关键词： heavy metal organic acid Agrogyron elongation hyperaccumulation