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H2 /H∞ control of networked control system with random time delays

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Science china(Information Sciences) 2011年第12期54卷 2635-2650页

作者： QIU Li 1,2 , XU BuGong 1 & LI ShanBin 1 1 college of Automation Science and Engineering, South china university of Technology, Guangzhou 510640, china 2 college of Mechatronics and Control Engineering, Shenzhen university, Shenzhen 518060, china college of Automation Science and Engineering South China University of Technology Guangzhou China college of Mechatronics and Control Engineering Shenzhen University Shenzhen China

This paper investigates the H 2 /H ∞ control problem for a class of discrete-time networked control systems with random communication time delays. Both sensor-to-controller (S-C) and controller-to-actuator (C-A) random network-induced delays are considered. Two independent Markov chains are used to model the S-C and C-A random delays. The resulting closed-loop system is a jump linear time-delay system induced by two Markov chains. Sufficient conditions for existence of H 2 /H ∞ controller are established by free-weighting matrix and stochastic Lyapunov functions. A simulation example illustrates the effectiveness of the proposed method.

关键词： H 2 /H ∞ control networked control systems Markov chains random time delays

分流喷管出口构型对红外抑制器性能影响的数值和实验研究

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红外与激光工程 2024年第2期53卷 58-70页

作者：杜家栋单勇张靖周南京航空航天大学能源与动力学院航空飞行器热管理与能量利用工业和信息化部重点实验室江苏南京210016

在模型实验验证的基础上,采用数值模拟的方法,对比分析了分流喷管出口构型对直升机红外抑制器气动性能、温度场和红外辐射强度的影响。研究结果表明:相比基准分流喷管模型(Origin),分流喷管出口带一定外扩张角的波瓣出口结构(Lobe_1)的... 详细信息

在模型实验验证的基础上,采用数值模拟的方法,对比分析了分流喷管出口构型对直升机红外抑制器气动性能、温度场和红外辐射强度的影响。研究结果表明:相比基准分流喷管模型(Origin),分流喷管出口带一定外扩张角的波瓣出口结构(Lobe_1)的引射系数略微降低、总压恢复系数降低,中间混合管出口排气温度峰值却降低了65.1 K,同时降低了混合管上下方区域的壁面温度,但造成混合管中后段外侧壁面局部区域温度升高;外扩张角为0的波瓣出口结构(Lobe_2)增加引射系数3.8%,总压恢复系数与Lobe_1结构基本相当,中间混合管出口排气温度峰值也降低了62.8 K,尤其是其降低混合管壁面温度的效果最佳;分流喷管出口突片结构(Tab)增加引射系数10.6%,但总压恢复系数降低0.7%,同时,内侧混合管出口排气平均温度降低19.3 K,混合管壁面降温效果相对较差。总体来看,波瓣和突片结构都起到增强引射、强化混合的作用,尤其是波瓣出口结构(Lobe_2)对降低抑制器总体红外辐射效果最好,在3~5μm波段的红外辐射强度最大可降低21%;在8~14μm波段,其红外辐射强度最大可降低15%。

关键词：红外抑制器分流喷管引射系数红外辐射气动性能

Deformation and Densification Laws of Powder Cold Forging

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Journal of Wuhan university of Technology(Materials Science) 2007年第1期22卷 17-21页

作者：余世浩 college of Material Science and Engineering Wuhan University of Technology

The deformation and densification laws of preform upsetting and closed-die forging were researched based on experimental results of cold forging of deoxidized Fe powder sintering porous material under different initial conditions such as friction factor, ratio between height and diameter and relative density. The fracture limit criteria＂ for powder cold-forging upsetting and the limit strain curve were achieved. The effect of friction facto,, ratlt, between height and diameter and relative density on fracture strain limitation was emphatically analyzed. The limit process parameter curves for the deformation of upsetting were also confirmed. Laws of deformation, densification and density distribution for closed-die forging of powder perform during cold-forging were further analyzed and discussed with the help of experimental phase analysis. As a result, this experiment established theoretical foundations for the design of preform and die as well as optimization of technological process parameters.

关键词： powder cold-forging fracture limit strain criterion deformation law densification mechanism

On the general expressions of finite Hankel transform

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Science china(Physics,Mechanics & Astronomy) 2010年第11期53卷 2125-2130页

作者： JIANG Quan 1,2 & GAO CunFa 1 1 college of Aerospace Engineering,Nanjing university of Aeronautics and Astronautics,Nanjing 210016,china 2 School of Civil Engineering,Nantong university,Nantong 226019,china college of Aerospace Engineering Nanjing University of Aeronautics and Astronautics Nanjing China School of Civil Engineering Nantong University Nantong China

The general expressions of finite Hankel transform are naturally deduced with the help of the property of Bessel *** equations in this paper can degenerate into three kinds of boundaries since all the coefficients in the boundary conditions are taken into *** results can be adopted in solving physics problems involving the finite Hankel transform.

关键词： hankel transform bessel function finite integral

Endothelial Nitric Oxide Synthase Gene Intron 4, 27 bp Repeat Polymorphism and Essential Hypertension in the Kazakh Chinese Population

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Acta Biochimica et Biophysica Sinica 2007年第5期39卷 311-316页

作者： Fengmei DENG~1 , Qinghua HU~(2,3), Bin TANG~4, Fang HE~(2,3), Shuxia GUO~2, Jiang CHEN~4, Feng LI~2, Xuehua WU~2, Jun ZHANG~2, Huimin ZHANG~2, Juan ZHAO~2, Hua ZHONG~2, Ling HE~2, Jun LI~2, Le ZHANG~(1,2), and Shuren WANG~(1*) 1 West china School of Preclinical and Forensic Medicine, Sichuan university, Chengdu 610044, china 2 Key Laboratory of Xinjiang Endemic and Ethnic Diseases Cooperated by Education Ministry with Xinjiang Province, college of Medicine, Shihezi university, Shihezi 832002, china 3 Key Laboratory for Respiratory Diseases, Health Ministry of china, Wuhan 430030, china 4 First Affiliated Hospital, college of Medicine, Shihezi university, Shihezi 832008, china West china School of Preclinical and Forensic Medicine Sichuan UniversityChengdu 610044 China Key Laboratory of Xinjiang Endemic and Ethnic Diseases Cooperated by Education Ministry with Xinjiang Province College of Medicine Shihezi UniversityShihezi 832002 China Key Laboratory for Respiratory Diseases Health Ministry of ChinaWuhan 430030 China First Affiliated Hospital College of Medicine Shihezi UniversityShihezi 832008 China

To investigate the relationship between 27 bp repeat polymorphism in intron 4 in the endothelial nitric oxide synthase (eNOS4) gene and essential hypertension in the Kazakh Chinese population, 151 patients with essential hypertension and 138 healthy people were selected from the Boertonggu countryside of Shawan region in the Xinjiang Uygur Autonomous Region of china in 2006. The polymorphism of eNOS in the two groups was detected with polymerase chain reaction assays and the genotype frequencies in each group were calculated following the Hardy-Weinberg law. Four and five tandem 27 bp repeats were designated as "a" and "b", respectively. It was found that the frequencies of b/b, b/a and a/a genotypes of the eNOS4 gene were 84.06%, 15.22% and 0.72% in the control group, and 81.46%, 15.89% and 2.65% in the hypertension group, respectively. The frequencies of gene "b" and "a" were 91.67% and 8.33% in the control group and 89.40% and 10.60% in the hypertension group, respectively. It was found that plasma eNOS activity was not associated with genotypes and alleles of eNOS gene. Plasma eNOS activity in the hypertension group was significantly decreased compared with the control group (P<0.01). The results suggest that eNOS4 gene polymorphisms are unlikely to be the major genetic susceptibility factors for essential hypertension in the Xinjiang Kazakh population. However, a positive association between plasma eNOS activity and essential hypertension has been revealed.

关键词： hypertension eNOS4 gene polymorphism Kazakh Chinese

cDNA Cloning of PDC1 and ADH1 Function Analysis in Job’s-tears

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cDNA Cloning of PDC1 and ADH1 Function Analysis in Job’s-te...

Antagonist peptides of human interferon-α2b isolated from phage display library inhibit interferon induced antiviral activity

中国植物生理学会第十次会员代表大会暨全国学术年会

作者： Daqing Chen*, Yanan Li, Shuangjian Chen, Yunfen Zhu* college of Life Science, yangtze university, jingzhou 434025, china

＜正＞Alcohol fermentation is a metabolism substitute pathway in plants under anaerobic stress, the pyruvate decarboxylase is the key enzyme in this pathway and is cruical for anaerobic tolerance of plants. job’s-tears

关键词： PDC1 cloning semi-quantitative PCR, ADH1 transgeneic plant analysis anaerobic stress job’s- tears tabacco arabidopsis

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Acta Pharmacologica Sinica 2006年第8期27卷 1044-1050页

作者： Wang TIAN~1 Gang BAI~(2,3) Zheng-he LI~2 Wen-bo YANG~2 ~1Department of Microbiology,college of Life Sciences,Nankai university,Tianjin 300071,china," 2college of Life Sciences,Nankai university,Tianjin 300071,china Department of Microbiology College of Life Sciences Nankai University Tianjin China college of Life Sciences Nankai University Tianjin China

Aim:To screen human interferon(IFN)-α2b antagonist peptides from a phagedisplayed heptapeptide ***:WISH cells and polyclonal anti-IFN-α2b antibodies were used to select IFN receptor-binding peptides from a phagedisplayed heptapeptide *** specific binding of phage clones was exam-ined by phage ELISA and *** specific binding activitiesof synthetic peptides to WISH cells were detected by competition *** synthetic peptides to IFN-induced antiviral activity were analyzed by evaluat-ing the cytopathic effect(CPE)using the MTT ***:Twenty-threepositive clones were obtained after seven rounds of *** clones wererandomly picked from the positive clones and were *** correspond-ing amino acid sequences suggested 3 groups homologous to the 3 domains ofIFN-α2b,defined by residues 24-41,43-49,and 148-158 of IFN-α*** theypresented as corresponding to IFN receptor-binding domains,AB loop and Ehelix,clone № 26 and 35 were chosen for further characterization and shown tobind to WISH *** peptides corresponding to clone № 26 and 35,desig-nated SP-7(SLSPGLP)and FY-7(FSAPVRY)were shown to compete with GFP-IFN-α2b for binding to its receptor and to inhibit the IFN-α2b-induced ***:Both IFN-α2b antagonist peptides,SP-7 and FY-7,wereable to inhibit the IFN-induced antiviral activity,and could be helpful in laying thefoundation for the molecular mechanism of the interaction between IFN and itsreceptor.

关键词： interferon-α2b antagonist peptide phage display type Ⅰ IFN receptor cell selection

A thin-layer spectroelectrochemical study of 3,3',5,5'-tetramethylbenzidine at SnO_2:F film optically transparent electrode

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Science china Chemistry 2004年第4期47卷 267-275页

作者： JIAO Kui1, YANG Tao2 & NIU Shuyan1,2 1. college of Chemistry and Molecular Engineering, Qingdao university of Science and Technology, Qingdao 266042, china 2. college of Chemistry and Chemical Engineering, Ocean university of china, Qingdao 266003, china Correspondence should be addressed to Jiao Kui college of Chemistry and Molecular Engineering Qingdao University of Science and Technology Qingdao China college of Chemistry and Chemical Engineering Ocean University of China Qingdao China

The electrooxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) is dependent on the pH value of Britton-Robinson (B-R) buffer solution. In this work, the electrooxidation behavior of TMB was investigated with a SnO2:F film optically transparent thin-layer spectroelectrochemical cell. TMB underwent one two-electron electrooxidation process in the pH range from 2.0 to < 4.0, and two successive one-electron electrooxidation processes in the pH range from 4.0 to < 7.0 in the B-R buffer solution. At pH 6.5, the electrooxidative product of TMB generated a subsequent chemical reaction to yield an azo compound. Several spectroelectrochemical techniques, such as thin-layer cyclic voltammetry, thin-layer cyclic voltabsorptometry, thin-layer potential-controlled electrolysis absorptometry, thin-layer single-potential-step chronoabsorptometry, thin-layer dou-ble-potential-step chronoabsorptometry, thin-layer single-potential-step open-circuit relaxation chronoabsorptometry, were applied to this investigation. The formal potential E0’ and the electron transfer number corresponding to the electrooxidation of TMB in B-R buffer solution, and the reaction rate constant of the subsequent chemical reaction were determined.

关键词： 3,3′,5,5′-tetramethylbenzidine tin oxide film optically transparent electrode thin-layer spectroelectro-chemistry electrooxidation

Cycloaddition mechanism for the resin-OsO_4-catalyzed of styrene: A DFT study

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Science china Chemistry 2008年第1期51卷 19-24页

作者： ZHANG XingHui1, WANG KeTai1 & FANG Ran2 1 college of Chemical Engineering, Gansu Unite university, Lanzhou 730000, china 2 college of Chemistry and Chemical Engineering, Sun Yat-sen university, Guangzhou 510275, china college of Chemical Engineering Gansu Unite University Lanzhou China college of Chemistry and Chemical Engineering Sun Yat-sen University Guangzhou China

The postulated intermediates in the base-free and base-assisted addition of OsO4 to styrene have been investigated at the B3LYP/6-311G** level of the theory. N(CH3)2(Ph) was chosen as the base of the resin-OsO4. According to our model calculations the [2+3] addition was found to be favorable with an activation of 2+2] cycloaddition remain high (>155.00 kJ/mol). In addition, the electronic structure analysis of the molecules was carried out by na- ture bond orbital (NBO). The computational results were in reasonable agreement with experimental results.

关键词： cycloaddition resin-OsO4 density functional theory