简介:Inthisletter,acomparisonbetweenthreetypes(twolinearandonenonlinear)ofmodelsofskeletalmusclestiffnessisshown.ResultsarecomparedwithexperimentaldataforbicepsbrachiiinthecaseofmusclestretchingandwiththeHillequationforabiologicalmuscle.Itisshownthatresultsfornonlinearstiffnessmodelincaseoflength-forcerelationshipfitstotheexperimentaldata.
简介:Itisalreadyknownthatthereareseveralnonlinearitycriteriasuchasalgebrajcdegree,nonlinearity,distancetolinearstructures,correlationimmune,propagationcriterion,differentialuniformity,whichareusedtocheckwhetheracryptographicfunctionisweakornot,inthispaperwewilldiscussthesecriteriafromavaluationpointofview,andconsiderthelargesttransformationgroupwhichleaveacriterioninvariant,whichisnameditssymmetrygroup.itcanserveasawayofcoparingthestabilityofnonlinearitycriteriaundertheactionofinvertibletransformations.
简介:BasedontheFenlon‘stheorytheparametriceffectsinfluidsduetothenonlinearinteractionofalowfrequencypumpingwaveandahighfrequencyprobingwaveareanalysed.TheexpressionsofpressureamplitudeofsumordifferencefrequencysidebandandthefromulaofnonlinearityparameterB/Aforlossymediumarederived.Theoreticalcalculationdemonstrated,thatthesidebandcomponentsincreaselinearlywithpumpsignal.Therefore,amethodfordeterminationofB/Aisprovidedandtheval-uesforseveralbiologicalfluidsandmixturesaremeasured.
简介:Thisstudypresentsageneralapproachtoderivetheacousticnonlinearityparametersinducedbyvarioustypesofdislocationconfigurationsincludingdislocationstrings(monopoles),dislocationdipoles,dislocationpileupsandextendeddislocations.Itisfoundthatexpressionsoftheacousticnonlinearityparameterinducedbysuchavarietyofdislocationcon-figurationsshareacommonmathematicalform.Theyareallscaledwith(Lch/b)n,whereLchisacharacteristiclengthofthedislocationconfiguration,bisthemagnitudeoftheBurgersvector,andniseither3or4.Semiquantitativeanalysisispresentedtocomparethemagnitudesoftheacousticnonlinearityparametersamongdifferenttypesofdislocationconfigurations.
简介:WeaddresstheimpactofnonlocalityinthephysicalfeaturesexhibitedbysolitonssupportedbyKerr-typenonlinearmediawithanimprintedopticallattice.WediscussthesolitonssolutionforaclassofnonlinearSchr¨odingerequationsintheopticallatticewithnonlocalnonlinearity.Wealsoshowviaauniformprioriestimatethatexistenceanduniquenessoftheglobalsolutionfortheinitialproblem.
简介:Thispaperisconcernedwiththeharmonicequation(P_(■ε)):?u=0,u>0inB~nand?u/?ν+((n-2)/2)u=((n-2)/2)Ku~(n/(n-2)■ε)onS~(n-1)whereB~nistheunitballinR~n,n≥4withEuclideanmetricg_0,?B~n=S~(n-1)isitsboundary,KisafunctiononS~(n-1)andεisasmallpositiveparameter.Weconstructsolutionsofthesubcriticalequation(P_(-ε))whichblowupatonecriticalpointofK.WegivealsoasufficientconditiononthefunctionKtoensurethenonexistenceofsolutionsfor(P_(-ε))whichblowupatonepoint.Finally,weproveanonexistenceresultofsinglepeakedsolutionsforthesupercriticalequation(P_(+ε)).
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简介:TheelectricalnonlinearityofsiliconmodulatorsbasedonreversedPNjunctionswasfoundtoseverelylimitthelinearityofthemodulators.Thiseffect,however,wasinadvertentlyneglectedinpreviousstudies.Consideringtheelectricalnonlinearityinsimulation,a32.2dBdegradationintheCDR3(i.e.,thesuppressionratiobetweenthefundamentalsignalandintermodulationdistortion)ofthemodulatorwasobservedatamodulationspeedof12GHz,andthespuriousfreedynamicrangewassimultaneouslydegradedby17.4dB.ItwasalsofoundthatthelinearityofthesiliconmodulatorcouldbeimprovedbyreducingtheseriesresistanceofthePNjunction.Thefrequencydependenceofthelinearityduetotheelectricalnonlinearitywasalsoinvestigated.
简介:§I.IntroductionInthispaperwearelookingforsolutionsofthefollowingHamiltoniansystemofsecondorder:wherex=(x1,x2)andVsatisfies(V.1)V:R×R2→RisaC1-function,1-periodicInt,(V.2)Visperiodicinx1withtheperiodT>0,(V.3)V→O,Vx→Oas|x2|→∞,uniformlyin(t,x1).
简介:Weexperimentallydemonstrateself-trappingoflight,asaresultofplasmonicresonantopticalnonlinearity,inbothaqueousandorganic(toluene)suspensionsofgoldnanorods.Thethresholdpowerforsolitonformationisgreatlyreducedintolueneasopposedtoaqueoussuspensions.Itiswellknownthattheopticalgradientforcesareoptimizedatoff-resonancewavelengthsatwhichsuspendedparticlestypicallyexhibitastrongpositive(ornegative)polarizability.However,surprisingly,aswetunethewavelengthoftheopticalbeamfromacontinuous-wave(CW)laser,wefindthatthethresholdpowerisreducedbymorethanthreefoldattheplasmonicresonancefrequency.Byanalyzingtheopticalforcesandtorqueactingonthenanorods,weshowtheoreticallythatitispossibletoalignthenanorodsinsideasolitonwaveguidechannelintoorthogonalorientationsbyusingmerelytwodifferentlaserwavelengths.Weperformaseriesofexperimentstoexaminethetransmissionofthesoliton-formingbeamitself,aswellasthepolarizationtransmissionspectrumofalow-powerprobebeamguidedalongthesolitonchannel.Itisfoundthattheexpectedsyntheticanisotropicpropertiesaretoosubtletobeclearlyobserved,inlargepartduetoBrownianmotionofthesolventmoleculesandalimitedorderingregionwheretheopticalfieldfromtheself-trappedbeamisstrongenoughtoovercomethermodynamicfluctuations.Theabilitytoachievetunablenonlinearityandnanorodorientationsincolloidalnanosuspensionswithlow-powerCWlaserbeamsmayleadtointerestingapplicationsinall-opticalswitchingandtransparentdisplaytechnologies.
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简介:Theevolutioncharacteristicsofamatter-wavebrightsolitonareinvestigatedbymeansofthevariationalapproachinthepresenceofspatiallyvaryingnonlinearity.Itisfoundthattheatomdensityenvelopeofthesolitonischangedasaresultofthespatialvariationofthes-wavescatteringlength.Thestablesolitoncanexistinappropriateinitialconditions.Themovementofthesolitondependsonthesignandvalueofthecoefficientofspatiallymodulatednonlinearity.Thesetheoreticalpredictionsareconfirmedbythefullnumericalsimulationsoftheone-dimensionalGross-Pitaevskiiequation.
简介:Themodulationinstabilityofquasi-plane-waveopticalbeamsisinvestigatedintheframeofgeneralizedSchrodingerequationwiththenonlineartermofageneralform.Generalexpressionsarederivedforthedispersionrelation,thecriticaltransversespatialfrequency,aswellastheinstabilitygrowthrate.Theanalysisgeneralizestheknownresultsreportedpreviously.Adetaileddiscussiononthemodulationinstabilityinbiasedcentrosymmetricphotorefractivemediaisalsogiven.