简介:Theliquidcrystalcompositematerialsconsistofmicrodroplersofliquidcrystalswhicharespontaneouslyformedinamatrixofapolymeratthetimeofitspolymerization.Thedirectorconfigurationinliquidcrystaldroplets.themodeloforientationofdroplets,andthecontrastratiosofacellareinvestigated.Dropletsize,spacinganddistributionarereadilycontrolledinthesematerialstoallowoptimizationofdisplaysbaseduponelectricallycontrolledlightscatteringfromtheliquidcrystaldroplets.Preliminaryexperimentalandtheoreticalstudiesofthelightscatteringandelectro-opticresponseofnewmaterialshowthatthesematerialscanoffernewfeaturessuitableforlargeareadisplaysandlightvalves.
简介:Theabilitytomodulateanopticalfieldviaanelectricfieldisregardedasakeyfunctionofelectro-opticinterconnects,whichareusedinopticalcommunicationsandinformation-processingsystems.Oneofthemaindevicesrequiredforsuchinterconnectsistheelectro-opticmodulator(EOM).CurrentEOMsbasedonelectro-opticandelectro-absorptioneffectsoftenarebulkyandpower-inefficientduetotheweakelectro-opticpropertiesoftheirconstituentmaterials.Here,weproposeanewmechanismtoproduceanarbitrary-waveformEOMbasedonquantuminterference,inwhichbothrealandimaginarypartsofthesusceptibilityareengineeredcoherentlywithsuper-highefficiency.BasedonthisEOM,awaveforminterconnectfromthevoltagetothemodulatedopticalabsorptionisrealized.Weexpectthatsuchanewtypeofelectro-opticinterconnectwillhaveabroadrangeofapplications,includinginopticalcommunicationsandnetworks.
简介:Afiniteelement-Helmholtzintegralhybridmethodhasbeendevelopedtocalculatetheelectro-acousticperformanceofafinitelengthcylindricaltransducerimmersedinwater.Thenumericalstudyconcernedwithelectricalimpedancesandbeampatternsofthetransducerispresented.Experimentaldataareshowntosupportthenumericalstudy.
简介:InstitutionofModernPhysics(IMP)hasdesigned,fabricatedandinstalledthefirstSRFcavityelectropolishingsystemofChina.It’ssizedfor1.3GHzSRFcavities,andalsocanworksformultiplecellcavitieswithfurtherupgradeofstructure.
简介:Thecreepeffectofsuspensionsinelectro-dynamicloudspeakerswasmodeledbasedonfractionalorderderivatives.Thefractionalstandardlinearsolid(FSLS)modelwaspresentedbysubstitutingtheAbeldashpotforNewtondashpotinStandardLinearSolid(SLS)model.TheelectricalimpedanceaswellasthetransferfunctionbetweendiaphragmdisplacementandinputvoltageofthetwotestedmidrangeloudspeakerswasmeasuredbyKlippellaseranalyzersystem,andthemodelparameterswereidentifiedbytheleast-mean-squaremethod.BycomparingthefittingresultsofFSLSmodelwiththeothertwoclassicalmodels-4ParameterLogarithmicmodelandSLSmodel,theresultsshowthattheFSLSmodelcanrightlypredictthefrequencydependentcompliancelossfactorandyieldhigheraccuracyformodelingthecreepeffectinloudspeakersuspensions.
简介:Thispaperaddressesanonlinearfeedbackcontrolproblemforthechaoticarchmicro-electro-mechanicalsystemwithunknownparameters,immeasurablestatesandpartialstate-constraintsubjectedtothedistributedelectrostaticactuation.Toreflectinherentpropertiesanddesigncontroller,thephasediagrams,bifurcationdiagramandPoincaresectionarepresentedtoinvestigatethenonlineardynamics.TheauthorsemployasymmetricbarrierLyapunovfunctiontopreventviolationofconstraintwhenthearchmicro-electro-mechanicalsystemfacessomelimits.AnRBFneuralnetworksystemintegratingwithanupdatelawisadoptedtoestimateunknownfunctionwitharbitrarilysmallerror.Toeliminatechaoticoscillation,aneuro-adaptivebacksteppingcontrolschemefusedwithanextendedstatetrackingdifferentiatorandanobserverisconstructedtolowerrequirementsonmeasuredstatesandprecisesystemmodel.Besides,introducinganextendedstatetrackingdifferentiatoravoidsrepeatedderivativeforthevirtualcontrolsignalassociatedwithconventionalbackstepping.Finally,simulationresultsarepresentedtoillustratefeasibilityoftheproposedscheme.
简介:影印石版术实验与electrooptically悦耳的阶段步借助于一个光阶段面具被执行。阶段面具由转换铁电体领域的六角形的格子在z切割锂niobate底层上制作了的2-dimensional组成。电镀物品光学地悦耳的阶段步在转换领域之间,被一个外部电场的应用程序经由透明电极沿着水晶的z轴获得。氩激光的瞄准横梁通过阶段面具和近的领域紧张模式,在Talbot长度并且为应用电压的不同价值的不同飞机,被用于光刻的实验。初步的结果被显示出,进一步的应用被讨论。这研究部分是的CLC数字TN305在FIRB工程以内由MIUR资助了(没有。RBNE01KZ94)并且部分由MIUR工程(号码77DDN.1105/2002)。
简介:Byusingthewell-developedintegraltransformmethodology,thedynamicresponseofstressandelectricdisplacementaroundafinitecrackinaninfinitepiezoelectricstripareinvestigatedunderarbitrarydynamicanti-planeloads.Thedynamicstressintensityfactorsandelectricdisplacementareobtainedanalytically.Itisshownthatthedynamiccrack-tipstressandelectricfieldstillhaveasquare-rootsingularity.Numericalcomputationsforthedynamicstressintensityfactorshowthattheelectricloadhasasignificantinfluenceonthedynamicresponseofstressfield.Thehighertheratioofthecracklengthtothewidthofthestrip,thehigherthepeakvalueofthedynamicstressintensityfactoris.Ontheotherhand,thedynamicresponseoftheelectricfieldisdeterminedsolelybytheappliedelectricload.Theelectricfieldwillpromoteorretardthepropagationofthecrackdependingonthetimeelapsesincetheapplicationoftheexternalelectro-mechanicalloads.