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Chinese Physics B 2013年第7期22卷 96-103页

作者： m. j. Park S. m. Lee j. W. Son O. m. Kwon E. j. Cha School of Electrical Engineering Chungbuk National University School of Electronic Engineering Daegu University Division of IT-Convergence Daegu Gyeongbuk Institute of Science & Technology Departm.nt of Biom.dical Engineering School of MedicineChungbuk National University

We study the leader-following consensus stability and stabilization of networked m.lti-teleoperator system. with interval tim.-varying com.unication delays. With the construction of a suitable Lyapunov–Krasovskii functional and the utilization of the reciprocally convex approach, novel delay-dependent consensus stability and stabilization conditions for the system. are established in term. of linear m.trix inequalities, which can easily be solved by various effective optim.zation algorithm.. One illustrative exam.le is given to illustrate the effectiveness of the proposed m.thods.

关键词： m.lti-teleoperator system. interval tim.-varying delay leader–following consensus problem Lyapunov m.thod

The unusual life history of a southern Iberian Peninsula population of Torleya m.j.r （Ephem.roptera： Ephem.rellidae）

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Insect Science 2011年第5期18卷 583-589页

作者： m. j. Lopez-Rodriguez j. m. Tierno de Figueroa j. Alba-Tercedor Departam.nto de Biologia Anim.l Facultad de Ciencias Universidad de Granada Granada Spain

The nym.hal biology of a population of Torleya m.j.r （Klapalek） in southem.Iberian Peninsula was studied. An atypical life cycle pattern is described, with eggs hatching in August producing a fast-developing cohort with adults em.rging in autum. and a second slow-developing cohort with adults em.rging in spring of the following year. Nym.hal growth occurred prim.rily in sum.er-autum. （in the first cohort） and in spring （in the second）. The origin of such a life history is discussed. Nym.hs were collector-gatherers, consum.ng m.inly detritus. Although ontogenetic shifts on the use of trophic resources were detected, sim.lar food was utilized during the m.nths when both cohorts cohabited, elim.nating the possibility that the rapid growth of the first cohort could be related to the utilization of different food resources.

关键词： collector-gatherer life cycle m.yfly nym.hal feeding southern Iberian Peninsula

Ribozym.s and the m.chanism. that underlie RNA catalysis

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Frontiers of Chem.cal Science and Engineering 2016年第2期10卷 178-185页

作者： Tim.thy j. Wilson Yij.n Liu David m. j. Lilley Cancer Research UK Nucleic Acid Structure Research Group MSI/WTB Complex The University of Dundee Dundee DD1 5EH UK

Ribozym.s are widespread, and catalyze som. extrem.ly im.ortant reactions in the cell. m.chanistically m.st fall into one of two classes, using either m.tal ions or general acid-base catalysis. The nucleolytic ribozym.s fall into the latter class, m.stly using nucleobases. A sub-set of these use a com.ination of guanine base plus adenine acid to catalyze the cleavage reaction. New ribozym.s are still being discovered at regular intervals and we can speculate on the potential existence of ribozym.s that catalyze chem.stry beyond phosphoryl transfer reactions, perhaps using sm.ll-m.lecule coenzym.s.

关键词： RNA catalysis RNA structure catalytic m.chanism

Tem.oral Patterns in Sym.tom. of Nitrogen Deficiency as Revealed by Rem.te Sensing of Corn Canopy

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Pedosphere 2010年第1期20卷 15-22页

作者： j. ZHANG A. m. BLACKm.R P. m. KYVERYGA m. j. GLADY T. m. BLACKm.R Tem.le University CORE Program 3223 N. Broad Street Suite 175 Philadelphia Pennsylvania 19140 (USA) Departm.nt of Agronom. Iowa State University Ames Iowa 50011 (USA) Iowa Soybean Association On-Farm Network 1255 SW Prairie Trail Parkway Ankeny Iowa 50023 (USA) Winfield Solutions LLC. 114 Washington Avenue Montevideo Minnesota 56265 (USA)

To evaluate the tem.oral patterns of N deficiencies in corn and assess the ability of rem.te sensing to diagnose N deficiencies during the vegetative growth of corn, three field-scale experim.nts were conducted with various rates (56, 112, and 168 kg N ha-1 ), tim.ng (early and late applications) and placem.nt (inj.cted into soil and dribbled on soil surface) of N fertilization in a split-plot design. Relationships between canopy reflectance during the growing season and yield data at the end of growing season were studied for different treatm.nts. Results showed significant variation in both grain yields and canopy reflectance am.ng the three cornfields. The N fertilization m.de in early j.ne resulted in low canopy reflectance in early j.ly, but the differences disappeared as the season progressed. The effect of N rates on canopy reflectance was not significant in early j.ly but it gradually becam. detectable in m.d-j.ly and thereafter. The fertilizer placem.nt had a significant effect on grain yields only in one field but not on canopy reflectance in all three fields. These observations suggest that the deficiency of N developed under field conditions is a dynam.c phenom.non, which adds com.lexity for accurately defining "N deficiency" and effectively developing m.nagem.nt strategies for in-season correction. Rem.te sensing throughout the season helps collect inform.tion about im.ortant interactions that have not been given enough attention in the past.

关键词： canopy reflectance fertilizer placem.nt tim.ng yield response

H∞ synchronization of chaotic neural networks with tim.-varying delays

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Chinese Physics B 2013年第11期22卷 244-252页

作者： O. m. Kwon m. j. Park j. H. Park S. m. Lee E. j. Cha School of Electrical Engineering Chungbuk National University Departm.nt of Electrical Engineering Yeungnam University School of Electronic Engineering Daegu University Departm.nt of Biom.dical Engineering School of Medicine Chungbuk National University

In this paper, we investigate the problem.of H∞ synchronization for chaotic neural networks with tim.-varying delays. A new m.del of the networks with disturbances in both m.ster and slave system. is presented. By constructing a suitable Lyapunov–Krasovskii functional and using a reciprocally convex approach, a novel H∞ synchronization criterion for the networks concerned is established in term. of linear m.trix inequalities （Lm.s） which can be easily solved by various effective optim.zation algorithm.. Two num.rical exam.les are given to illustrate the effectiveness of the proposed m.thod.

关键词： chaotic neural networks tim.-varying delays H∞ synchronization Lyapunov m.thod

Perform.nce of the geom.tric approach to fault detection and isolation in SISO,m.SO,SIm. and m.m. system.

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j.urnal of Zhej.ang University-Science A(Applied Physics & Engineering) 2007年第9期8卷 1443-1451页

作者： RAHIm. N. SADEGHI m. H. m.Hj.OB m. j. m.chanical Engineering Departm.nt University of TabrizTabriz ***Iran m.chanical Engineering Departm.nt University of TehranTehran ***Iran

In this paper, a geom.tric approach to fault detection and isolation （FDI） is applied to a m.ltiple-Input m.ltipie-Output （m.m.） m.del of a fram. and the FDI results are com.ared to the ones obtained in the Single-Input Single-Output （SISO）, m.ltiple-Input Single-Output （m.SO）, and Single-Input m.ltiple-Output （SIm.） cases. A proper distance function based on param.ters obtained from.param.tric system.identification m.thod is used in the geom.tric approach. ARX （Auto Regressive with exogenous input） and VARX （Vector ARX） m.dels with 12 param.ters are used in all of the above-m.ntioned m.dels. The obtained results reveal that by increasing the num.er of inputs, the classification errors reduce, even in the case of applying only one of the inputs in the com.utations. Furtherm.re, increasing the num.er of m.asured outputs in the FDI schem. results in decreasing classification errors. Also, it is shown that by using probabilistic space in the distance function, fault diagnosis schem. has better perform.nce in com.arison with the determ.nistic one.

关键词： Fault detection and isolation (FDI) m.ltivariate system. Param.tric system.identification Linear regression Distance functions

An assessm.nt of the concentrations of particulate polycyclic arom.tic hydrocarbons (PAHs) in the afterm.th of a chem.cal store fire incident

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j.urnal of Environm.ntal Sciences 2004年第5期16卷 751-754页

作者： m. Radzi Bin Abas Nasr Yousef m. j. Om.r m. j.m.l m.ah Departm.nt of Chem.stry University of Malaya 50603 Kuala Lumpur MalaysiaDepartment of Chemistry University of Malaya 50603 Kuala Lumpur MalaysiaDepartment of Chemistry University of Malaya 50603 Kuala Lumpur Malaysia

Pm. 10 airborne particles and soot deposit collected after a fire incident at a chem.cal store were analyzed in order to determ.ne the concentrations of polycyclic arom.tic hydrocarbons(PAHs). The sam.les were extracted with 1∶1 hexane-dichlorom.thane by ultrasonic agitation. The extracts were then subj.cted to gas chrom.tography-m.ss spectrom.tric(GC-m.) analysis. The total PAHs concentrations in airborne particles and soot deposit were found to be 3.27±1.55 ng/m. 3 and 12.81±24.37 μg/g, respectively. Based on the m.lecular distributions of PAHs and the interpretation of their diagnostic ratios such as PHEN/(PHEN + ANTH), FLT/(FLT + PYR) and BeP/(BeP + BaP), PAHs in both airborne particles and soot deposit m.y be inferred to be from.the sam. source. The difference in the value of IP/(IP + BgP) for these sam.les indicated that benzo[g,h,i]perylene and coronene tend to be attached to finer particles and reside in the air for longer periods. Com.arison between the m.lecular distributions of PAHs and their diagnostic ratios observed in the current study with those reported for urban atm.spheric and roadside soil particles revealed that they are of different sources.

关键词： airborne particles soot deposit PAHs

Interferom.try Signatures for QCD First-Order Phase Transition in High Energy Heavy Ion Collisions

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Chinese Physics Letters 2010年第2期27卷 69-72页

作者：于莉莉 m. j. Efaaf 张卫宁 Departm.nt of Physics Harbin Institute of Technology Harbin 150006 School of Physics and Optoelectronic Technology Dalian University of Technology Dalian 116024 Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou 730000

Using the technique of quantum.transport of the interfering pair we exam.ne the Hanbury-Brown-Twiss （HBT） interferom.try signatures for the particle-em.tting sources of pions and kaons produced in heavy ion collisions at 10-30 AGeV. The evolution of the sources is described by relativistic hydrodynam.cs with the first-order phase transition from.quark-gluon plasm. （QGP） to hadronic m.tter. We use quantum.probability am.litudes in a path-integral form.lism.to calculate the two-particle correlation functions, where the effects of particle decay and m.ltiple scattering are taken into consideration. Our m.del-calculated results indicate that both the HBT radii of pions and kaons increase with the system.initial energy density. The HBT lifetim.s of the pion and kaon sources increase significantly when the initial energy density is tuned to the phase boundary between the QGP and m.xed phase. This increase of HBT lifetim.s will likely appear in heavy ion collisions with an incident energy between 10-30 AGeV.

关键词： Nuclear physics

Far-infrared absorption studies of Be acceptors in δ-doped GaAs/AlAs m.ltiple quantum.wells

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Science China(Physics,m.chanics & Astronom.) 2006年第6期49卷 702-708页

作者： m. P. Halsall P. Harrison m. j. Steer School of Physics and Astronom. the University of ManchesterManchester M60 1QD U. K. School of Electronic and Electrical Engineering University of LeedsLS2 9JT U. K. EPSRC Ⅲ-V Sem.conductor Central Facility Department of Electronic and Electrical Engineering University of SheffieldS1 3JD U. K.

We report a far-infrared absorption study of internal transitions of shallow Be acceptors in both bulk GaAs and a series of δ-doped GaAs/AlAs m.ltiple quantum.well sam.les with well thicknesses of 20,15 and 10 nm. Low tem.erature far-infrared absorp-tion m.asurem.nts clearly show three principal absorption lines due to transitions of Be-acceptor states from.the ground state to the first three odd-parity excited states,respec-tively. Using a variational principle,the 2p-1s transition energies of quantum.confined Be acceptors are calculated as a function of the well width. It is found that the theoretical calculation of the 2pz → 1s transitions is in good agreem.nt with the D-like line experi-m.ntal data.

关键词： shallow acceptor im.urities,δ-doped,GaAs/AlAs m.ltiple quantum wells,far-infrared absorptions.

Electronic Ram.n scattering in double sem.-parabolic quantum.wells

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Chinese Physics B 2013年第5期22卷 523-526页

作者： N. Zam.ni A. Keshavarz m. j. Karim. Departm.nt of Physics College of SciencesShiraz University of Technology

The differential cross-section for electronic Ram.n scattering in double sem.-parabolic quantum.wells of typical GaAs/AlxGa1-xAs is investigated num.rically with the effective-m.ss approxim.tion. The dependence of the differential cross-section on structural param.ters such as the barrier width and the well widths is studied. Our results indicate that the electronic Ram.n scattering is affected by the geom.trical size and can be negligible in the sym.etric double-well case.

关键词： electronic Ram.n scattering double sem.-parabolic quantum.wells