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Series-based approximate approach of optimal tracking control for nonlinear systems with time-delay

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Progress in Natural science:Materials International 2008年第12期18卷 1571-1576页

作者： Gongyou Tang~a Mingqu Fan~(a,b) a college of information science and Engineering,Ocean university of {4.,Qingdao 266100,{4. b college of information and Engineering,Shandong university of science and technology,Jinan 250031,{4. [a]college of information science and Engineering Ocean University of China Qingdao 266100 China [b]college of information and Engineering Shandong University of Science and Technology Jinan 250031 China

The optimal output tracking control (OTC) problem for nonlinear systems with time-delay is *** a series-based approx- imate approach,the original OTC problem is transformed into iteration solving linear two-point boundary value problems without time- *** OTC law obtained consists of analytical linear feedback and feedforward terms and a nonlinear compensation term with an infinite series of the adjoint *** truncating a finite sum of the adjoint vector series,an approximate optimal tracking control law is obtained.A reduced-order reference input observer is constructed to make the feedforward term physically *** exam- ples are used to test the validity of the series-based approximate approach.

关键词： Nonlinear systems Time-delay Tracking control Optimal control Observer

Development and application of ergodicity model with FRCM and FLAR for hydrological process

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science china(Technological sciences) 2009年第2期52卷 379-386页

作者： WANG HongRui1, FENG QiLei2, LIN Xin3 & ZENG WenYi4.1 college of Water science, Key Laboratory for Water and Sediment sciences of the Ministry of Education, beijing Normal {4., beijing 100875, china 2 School of science, beijing Institute of Education, beijing 100011, china 3 School of Mathematical sciences, beijing Normal {4., beijing 100875, china 4.college of information science and technology, beijing Normal {4., beijing 100875, china 1. college of Water science Key Laboratory for Water and Sediment Sciences of the Ministry of Education Beijing Normal University Beijing 100875 China 2. School of science Beijing Institute of Education Beijing 100011 China 3. School of Mathematical sciences Beijing Normal University Beijing 100875 China 4. college of information science and technology Beijing Normal University Beijing 100875 China

In this paper, a new ergodic property analysis model of hydrological process is proposed based on fuzzy-rough c-means clustering (FRCM), autocorrelogram, and fuzzy least absolute regression (FLAR). A precipitation time series (1951―2004. from Shanghai Hydrology Station is then analyzed with the model. The results show that the precipitation time series of April, May, June, and September has er-godic property. We conclude that in the long run, the precipitation of April, May, June, and September will not keep decreasing; it will converge to its mean value in some period.

关键词： hydrological process ergodic autocorrelogram fuzzy-rough c-means clustering fuzzy least absolute regression

Robust Design for Generalized Minimum Variance Controllers

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International Journal of Minerals,Metallurgy and Materials 1999年第2期13卷 144-148页

作者： Heping Liu Xin Shim (information Engineering School, university of science and technology {4., {4. 100083, china) (Shenyang Aircraft Corporation, Shenyang 110034. china) information Engineering School University of Science and Technology Beijing Beijing 100083 China Shenyang Aircraft Corporation Shenyang 110034 China

In order to improve the robustness and noise resistance of generalized minimum valance cothrol systems, several generalizedminimum variance control schemes are synthetically analyzed. The output variance caused by stochastic noise is decomposed to two parts. One part accords with the output variance of minboum vedance control and the other is the additional term of output variance causedby the control weighting factors. At the same time, the sensitivity function of modeling error is also deduced. A new robast design method that can minimize the sensitivity and the additional part of output variance is Presented by regulating variable parameters of contollers. The simulation results of self-tuning control show the effect of this method.

关键词： generalized minimum variance control variance robustness sensitivity

Influence of mesoscale topography on vortex intensity

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Progress in Natural science:Materials International 2008年第1期18卷 71-78页

作者： Zhexian Luo*,Yun Gao Remote Sensing college,Nanjing university of information science and {4.,Najing 21004.,china Remote Sensing college Nanjing University of Information Science and Technology Najing 210044 China

The effect of mesoscale topography on multi-vortex self-organization is investigated numerically in this paper using a barotropic prim- itive equation model with topographic *** the initial field there are one DeMaria major vortex with the maximum wind radius rm of 80 km at the center of the computational domain,and four meso-b vortices in the vicinity of rm to the east of the major vortex center. When there is no topography present,the initial vortices self-organize into a quasi-final state flow pattern,i.e.a quasi-axisymmetric vor- tex whose intensity is close to that of the initial major ***,when a mesoscale topography is incorporated,the spatial scale of the quasi-final state vortex reduces,and the relative vorticity at the center of the vortex and the local maximum wind speed remarkably *** possible mechanism for the enhancement of the quasi-final state vortex might be that the negative relative vorticity lump, generated above the mesoscale topography because of the constraint of absolute vorticity conservation,squeezes the center of positive vorticity towards the mountain slope area,and thus reduces the spatial range of the major ***,because the total kinetic energy is basically conservative,the squeezing directly leads to the concentration of the energy in a smaller area,*** strengthening of the vortex.

关键词： Mesoscale topography Vortex Self-organization Intensity change

Effect of surfactants on the structure and photoelectric properties of ITO films by sol-gel method

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Rare Metals 2010年第2期29卷 143-148页

作者： LIU Jiaxiang, WU Da, ZHANG Nan, and WANG Yue college of Materials science and Engineering, beijing university of Chemical {4., beijing 100029, china college of Materials science and Engineering Beijing University of Chemical Technology

The Indium tin oxide（ITO） thin film possesses excellent photoelectric properties that enable it to act as an ideal transparent *** obtain high-quality ITO films through sol-gel method, the ionic surfactant monoethanolamine and the non-ionic surfactant polyethylene glycol（PEG） were added to the ITO precursor *** influences of surfactants on the structural and photoelectric properties of ITO film samples were *** patterns indicated that surfactant monoethanolamine contributed to film predominant grain orientation along the（4.0） *** high transmittance（over 95%） was attributed to the preferred orientation and the grain size expansion of ITO *** showed that the surface particle size and the morphology of ITO films were strongly dependent on the kind of surfactants *** to the shortwave region, the absorption edge of the films exhibited the Burstein-Moss shift.

关键词： surfactants indium tin oxide films sol-gel structure photoelectricity

A characterization for a graphic sequence to be potentially C_r-graphic

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science china Mathematics 2010年第11期53卷 2893-2905页

作者： YIN JianHua Department of Mathematics, college of information science and technology, Hainan {4., Haikou 570228, china 1. Department of Mathematics College of Information Science and Technology Hainan University Haikou 570228 China

Let r 3, n r and π = (d1, d2, . . . , dn) be a graphic sequence. If there exists a simple graph G on n vertices having degree sequence π such that G contains Cr (a cycle of length r) as a subgraph, then π is said to be potentially Cr-graphic. Li and Yin (2004. posed the following problem: characterize π = (d1, d2, . . . , dn) such that π is potentially Cr-graphic for r 3 and n r. Rao and Rao (1972) and Kundu (1973) answered this problem for the case of n = r. In this paper, this problem is solved completely.

关键词： graph cycle degree sequence

Study on Tibetan Chicken embryonic adaptability to chronic hypoxia by revealing differential gene expression in heart tissue

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science china(Life sciences) 2009年第3期52卷 284-295页

作者： LI Mei & ZHAO ChunJiang college of Animal science and technology,china Agricultural {4.,beijing 100193,china 1. college of Animal science and technology China Agricultural University Beijing 100193 China

Oxygen concentration is essential for appropriate *** can exert a significant impact on physiological alteration of the cell and *** Chicken(Gallus gallus) is a Chinese indigenous breed inhabiting in Tibetan areas,which is also a chicken breed living at high altitude for the longest time in the *** has developed an adaptive mechanism to hypoxia,which is demonstrated by that Tibetan Chicken has much higher hatchability than low-land chicken breeds in high-altitude areas of *** the present study,Tibetan Chicken fertilized full sib eggs were incubated up to Hamburger-Hamilton stage 4. under 13% and 21% oxygen concentration,*** Chicken and Dwarf Recessive White Chicken were used as control *** hearts in all of the 3 chicken breeds under hypoxic and normoxic conditions were isolated and hybridized to Genechip Chicken Genome Array to study molecular mechanisms underlying the adaptation to high altitude of Tibetan *** a result,50 transcripts highly expressed in hypoxia are screened *** up-regulated genes,some are involved in the gene ontology(GO) such as cell growth,cell difference,muscle contraction and signal ***,the expression levels of 21 transcripts are lower in hypoxia than those in *** down-regulated genes take part in cell communication,ion transport,protein amino acid phosphorylation and signal ***,gene enrichment analyses of these differential gene expressions are mainly associated with immune system response and ion channel activity in response to ***,the transcriptional expression profiles analyzed by hierarchical clustering and CPP-SOM software in all of the 3 different chicken breeds revealed that Tibetan Chicken is much closely related to Shouguang Chicken rather than Dwarf Recessive White *** addition,12 transcripts of Tibetan Chicken breed-specific expressed genes were identified,which seem to result in a more

关键词： adaptation chronic hypoxia gene chip chicken genome array Tibetan Chicken(Gallus gallus) differential gene expression

yellow^0,a marker for low body weight in Drosophila melanogaster

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science china(Life sciences) 2009年第7期52卷 672-682页

作者： Li XinHai & Deng XueMei college of Animal science and technology,china Agricultural {4.,beijing 100193,china 1. college of Animal science and technology China Agricultural University Beijing 100193 China

Marker-assisted selection(MAS) is an important modern breeding technique,but it has been found that the effect of the markers for quantitative trait loci(QTL) is inconsistent,leading in some cases to MAS failure and raising doubts about its *** the model organism Drosophila melanogaster was employed to study whether an effective marker could be found and applied to *** crossed the stock carrying the y0 marker(a recessive mutation allele of the yellow gene on the X chromosome) with three other stocks carrying corresponding wild-type markers in an F2 design,and found that the y0 marker was in significant association with low body weight(P<0.001).This association was consistent across different backgrounds and the marker effects in female and male were approximately 0.95 σP(phenotypic standard deviation) and 0.68 σP,*** next introgressed a fragment via the y0 marker into a wild stock background over 20 generations of marker-assisted introgression(MAI),and constructed the introgression stock y0(OR)20 in which body weight decreased by 13% and 7%,in female and male,respectively,compared to the wild stock(P<0.0001).This indicated that there must be a single QTL for low body weight that is tightly linked to the y0 *** then shortened the introgressed fragment to less than 1.5 cM by a deeper MAI using the y0 marker and the white *** narrower fragment also resulted in a similar decrease in body weight to that induced by y0(OR)20,indicating that the QTL for low body weight is located within this less-than-1.5 cM *** characteristics of the y0 marker by PCR amplification and Southern blotting revealed that yellow gene was deficient in the y0 stock,leading to disappearance of melanin from the cuticle and probably influencing the developmental *** above results confirmed the existence of effective QTL markers applicable to MAS breeding schemes,and their potential application in breeding new stocks.

关键词： Drosophila low body weight yellow quantitative trait loci marker-assisted selection introgression

Approximately optimal tracking control for discrete time-delay systems with disturbances

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Progress in Natural science:Materials International 2008年第2期18卷 225-231页

作者： Gongyou Tang a,,Huiying Sun b,Haiping Pang c a college of information science and Engineering,Ocean university of {4.,Qingdao 266100,{4. b college of information and Electrical Engineering,Shandong university of science and technology,Qingdao 266510,{4. c college of Automation and Electronic Engineering,Qingdao university of science and technology,Qingdao 26604.,{4. college of information science and Engineering Ocean University of China Qingdao 266100 China college of information and Electrical Engineering Shandong University of Science and Technology Qingdao 266510 China college of Automation and Electronic Engineering Qingdao University of Science and Technology Qingdao 266042 China

Optimal tracking control (OTC) for discrete time-delay systems affected by persistent disturbances with quadratic performance index is considered. By introducing a sensitivity parameter,the original OTC problem is transformed into a series of two-point boundary value (TPBV) problems without time-advance or time-delay terms. The obtained OTC law consists of analytic feedforward and feedback terms and a compensation term which is the sum of an infinite series of adjoint vectors. The analytic feedforward and feedback terms can be found by solving a Riccati matrix equation and two Stein matrix equations. The compensation term can be obtained by using an iteration formula of the adjoint vectors. Observers are constructed to make the approximate OTC law physically realizable. A simulation example shows that the approximate approach is effective in tracking the reference input and robust with respect to exogenous persistent disturbances.

关键词： Discrete systems Time-delay systems Disturbances Optimal control Tracking control