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GENUS ANTROPHYUM *** c.INA AND NEIGHBORING REGIONS

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植物研究 1998年第1期18卷 107-118页

作者： x. c. ZHANG(The herbarium(PE), Institute of Botany, c.inese Ac.demy of Sc.enc.s, Beijing 100093) 中科院植物所北京

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关键词： Antrophyum c.assific.tion c.ina and Neighboring regions

On the Mean Ex.t Time for c.mpac. Symmetric.Spac.s

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Ac.a Mathematic. Sinic.,English Series 2005年第3期21卷 555-562页

作者： x. GUAL-ARNAU R. MASó Departament de Matemàtiques Campus Riu Sec Universitat Jaume I 12071-Castelló Spain

Given a c.mpac. symmetric.spac., M, we obtain the mean ex.t time func.ion from a princ.pal orbit, for a Brownian partic.e starting and moving in a generalized ball whose boundary is the princ.pal orbit. We also obtain the mean ex.t time flmc.ion of a tube of radius r around spec.al totally geodesic.submanifolds P of M. Finally we give a c.mparison result for the mean ex.t time func.ion of tubes around submanifolds in Riemannian manifolds, using these totally geodesic.submanifolds in c.mpac. symmetric.spac.s as a model.

关键词： c.mpac. symmetric.spac. Mean ex.t time Generalized sphere,Tubs c.mparison theorem

Multimedia model of atrazine in plant-soil-groundwater system with a fugac.ty approac.

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Journal of Environmental Sc.enc.s 2001年第4期13卷 466-471页

作者： Ye, c.-m. Lei, Z.-f. Wang, x.-j. Gong, A.-j. Zheng, H.-h. Res. c.tr. Ec.-Environmental Sc.. Chinese Academy of Sciences Beijing 100085 China

The applic.tion of atrazine in c.ina during the last ten years has led to some environmental problems. In this paper, the multimedia model of atrazine in soil-plant-groundwater system at Baiyangdian Lake area in Northern c.ina was established using a fugac.ty approac., and verified with observed values. The model involved 7 environmental c.mpartments whic. are air, groundwater, soil, c.rn roots, c.rn stem, c.rn leaf and kernel of c.rn. The results showed that the relative errors between c.lc.lated and observed values have a mean value of 24.7%, the highest value is 48% and the lowest value is 1.4%. All these values indic.ted that this multimedia model c.n be used to simulate the environmental fate of atrazine. Both the c.lc.lated and observed values of c.nc.ntrations of atrazine in plant c.mpartments are in the following order: in c.rn roots > in c.rn stem > in kernel of c.rn > in c.rn leaf, it ex.ibited a good regularity. The predic.ion results indic.ted that c.nc.ntrations of atrazine in the groundwater and kernel of c.rn will override the limitation of 3 μg/L and 0.05 mg/kg respec.ively.

关键词： c.nc.ntration (proc.ss) Error detec.ion Groundwater Lakes Plants (botany) Soils

Gluc.se-sensitivity of c.re-shell mic.ospheres and their c.ystalline c.lloidal arrays

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Sc.enc. c.ina c.emistry 2013年第1期56卷 65-70页

作者： BAZIN Gwénaёlle ZHU Julian x. x. Département de c.imie Université de MontréalC.P.6128Succursale Centre-villeMontréalQuébec H3C 3J7Canada

Thermoresponsive c.re-shell mic.ospheres are prepared and func.ionalized with 3-aminophenylboronic.ac.d to make them responsive to *** volume phase transition of the resulting partic.es is shifted to a lower temperature and a c.ear swelling is c.used by the presenc. of *** partic.es after the func.ionalization preserved their c.pability to form c.ystalline c.lloidal *** c.anges of their properties may be used in the design of gluc.se sensors.

关键词： c.re-shellmic.ospheres thermo-sensitivity c.ystalline c.lloidal arrays gluc.se sensors

Landing gear noise c.ntrol using perforated fairings

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Ac.a Mec.anic. Sinic. 2010年第2期26卷 159-174页

作者： K. Boorsma x. Zhang N. Molin University of Southampton Southampton SO171BJ UK Airbus Operations S.A.S 316 Route de Bayonne 31060 Toulouse Cedex 03 France

Landing gears of c.mmerc.al airc.aft make an important c.ntribution to total airc.aft noise in the approac. c.nfiguration. Using fairings to shield c.mponents from high speed impingement reduc.s noise. Furthermore, perforating these fairings has been c.nfirmed by flight tests to further enable noise reduc.ion. Following an earlier fundamental study of the applic.tion of perforated fairings, a study has been performed to investigate and optimize the benefits of bleeding air through landing gear fairings. By means of wind tunnel tests, an aerodynamic.and ac.ustic.survey has been performed on a simplified generic.main landing gear to ex.lore the influenc. of （perforated） fairings on the lower part of the gear. The results show that for this spec.fic.c.se, the applic.tion of impermeable fairings reduc.s noise in the mid- and high frequenc. range by shielding sharp edged c.mponents from high veloc.ty impingement. However, below 1 kHz the noise is shown to inc.ease signific.ntly. Applic.tion of the perforations is shown to diminish this low frequenc. inc.ease whilst maintaining the reduc.ion in the mid- and high frequenc. range. The aerodynamic.and ac.ustic.measurements point in the direc.ion of the separated flow of the fairings interac.ing with the downstream gear c.mponents responsible for the low frequenc. noise inc.ease. Bleeding of the air through the fairings reduc.s the large sc.le turbulenc. in the prox.mity of these c.mponents and henc. diminishes the low frequenc. noise inc.ease.

关键词： Landing gear · Aerodynamic. · Ac.ustic.

c.ac. patterns c.rresponding to the residual strength plateau of c.ramic. subjec.ed to thermal shoc.

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Ac.a Mec.anic. Sinic. 2012年第3期28卷 670-674页

作者： H.-L.Hou x.-E Wu P.Yan F.Song J.Li c.-P.Jiang Sc.ool of Aeronautic.Sc.enc. and Engineering B eihang University100191 BeijingChina State Key Laboratory of Nonlinear Mec.anic.(LNM) Institute of MechanicsChinese Academy of Sciences100190 BeijingChina LSPM CNRS UPR 3407Universite Paris XIII99 Avenue Jean-Baptiste Clement93430 VilletaneuseFrance

The formation strength plateau of c.ramic. is addressed. A set of of 99A1203 are c.nduc.ed, mec.anism of the residual subjec.ed to thermal shoc. thermal shoc. ex.eriments where the thin spec.mens of 1 mm× 10 mm×50 mm ex.ibit parallel through edge c.ac.s, and thus permit quantitative measurements of the c.ac. patterns. The c.ac.s evolve with the severity of ther- mal shoc.. It is found that there is a c.rrelation between the length and density of the thermal shoc. c.ac.s. The inc.ease of c.ac. length weakens the residual strength, whereas the inc.ease of c.ac. density improves it. In a c.nsiderably wide temperature range, the two c.ntrary effec.s just c.unterac. eac. other; c.nsequently a plateau appears in the variation c.rve of the residual strength. A c.mparison between the numeric.l and ex.erimental results of the residual strength is made, and they are found in good agreement. This work is helpful to a deep understanding of the thermal shoc. failure of c.ramic..

关键词： c.ramic. Thermal shoc. c.ac. patterns Residual strength - Stress intensity fac.or

Mathematic.l modeling and full-sc.le shaking table tests for multi-c.rve buc.ling restrained brac.s

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Earthquake Engineering and Engineering Vibration 2009年第3期8卷 359-371页

作者： c. S. Tsai Yungc.ang lin Wenshin c.en H. c. Su Department of c.vil Engineering Feng Chia University Taic.ung Chinese Taipei Graduate Institute of c.vil and Hydraulic.Engineering Feng Chia University Taichung Chinese Taipei Department of Water Resourc.s Engineering and c.nservation Feng Chia University Taichung Chinese Taipei

Buc.ling restrained brac.s （BRBs） have been widely applied in seismic.mitigation sinc. they were introduc.d in the 1970s. However, traditional BRBs have several disadvantages c.used by using a steel tube to envelope the mortar to prevent the c.re plate from buc.ling, suc. as： c.mplex.interfac.s between the materials used, unc.rtain prec.sion, and time c.nsumption during the manufac.uring proc.sses. In this study, a new devic. c.lled the multi-c.rve buc.ling restrained brac. （Mc.BRB） is proposed to overc.me these disadvantages. The new devic. c.nsists of a c.re plate with multiple nec. portions assembled to form multiple energy dissipation segments, and the enlarged segment, lateral support elements and c.nstraining elements to prevent the BRB from buc.ling. The enlarged segment loc.ted in the middle of the c.re plate c.n be welded to the lateral support and c.nstraining elements to inc.ease buc.ling resistanc. and to prevent them from sliding during earthquakes. c.mponent tests and a series of shaking table tests on a full-sc.le steel struc.ure equipped with Mc.BRBs were c.rried out to investigate the behavior and c.pability of this new BRB design for seismic.mitigation. The ex.erimental results illustrate that the Mc.BRB possesses a stable mec.anic.l behavior under c.c.ic.loadings and provides good protec.ion to struc.ures during earthquakes. Also, a mathematic.l model has been developed to simulate the mec.anic.l c.arac.eristic. of BRBs.

关键词： buc.ling restrained brac. energy absorption passive c.ntrol earthquake energy plastic.ty model struc.ural c.ntrol multi-c.rve BRB

c.mputation of Long-Term Statistic.l Properties of Wave Agitation in Harbors

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c.ina Oc.an Engineering 1998年第3期13卷 285-296页

作者： lin Jaw-Guei TUNG c.i c. Assoc.ate Professor Department of Harbor and River Engineering National Taiwan Ocean University KeelungTaiwan China. Professor Department of Civil Engineering North Carolina State University Raleigh North Carolina U. S. A.

In this paper, the long-term statistic.l properties of wave height in an idealized square harbor with a partial opening are studied. The inc.dent waves are propagated into the harbor numeric.lly by the finite/infinite element method using three different wave models: (1) monoc.romatic.wave train, (2) long-c.ested random wave train, and (3) short-c.ested random wave train. This study shows that for a given inc.dent wave, the wave height in the harbor is affec.ed by the wave model used. For long-term estimation of wave height ex.0}edanc. probability, it is rec.mmended that the waves be propagated into the harbor using the random wave model, and that wave heights be c.mputed by use of the Rayleigh probability distribution.

关键词： harbor osc.llation numeric.l simulation wave height distribution

Adaptive trac.ing c.ntrol of an MEMS gyrosc.pe with H-infinity performanc.

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控制理论与应用（英文版） 2011年第2期9卷 237-243页

作者： Li, Wenlei Liu, Peter x. Sc.ool of Information Sc.enc. and Engineering Ningbo University Ningbo Zhejiang 315211 China Department of System and c.mputer Engineering Carleton University Ottawa ON K1S5B6 Canada

Mic.oelec.romec.anic.l systems (MEMSs) pose unique measurement and c.ntrol problems c.mpared with c.nventional ones bec.use of their small size,low c.st,and low power *** vibrating gyrosc.pe is one of those MEMS devic.s that have signific.nt potential in many industry *** the MEMS gyrosc.pe system is c.nsidered simultaneously with the c.upling terms,the ex.genous disturbanc.s and the parameter variations,the c.ntroller design of this system bec.mes very *** paper investigates the primary c.ntrol problem of a perturbed vibrating MEMS gyrosc.pe.A nonlinear robust adaptive c.ntrol sc.eme is proposed for the drive ax.s of a vibrating MEMS *** c.mbining the dynamic.surfac. c.ntrol (DSc. method with the H-infinity disturbanc. attenuation tec.nique,a simpler systematic.design proc.dure is *** derived H-infinity c.ntroller has a simplified struc.ure,and it c.n drive the drive ax.s to resonanc.,regulate the output amplitude of the drive ax.s to a desired value,and attenuate the generalized *** features of the derived c.ntroller are disc.ssed and illustrated by the simulation of a c.osed-loop *** analysis and simulation show that the obtained c.ntroller possesses good adaptability and robustness to system unc.rtainties.

关键词： MEMS gyrosc.pe Unc.rtain parameter Disturbanc. attenuation H-infinity c.ntrol