简介:Averysimpleschemeispresentedforteleportinganunknownfrequencystatewiththesuccessfulprobabilityof50%.Twoacoustic-opticalmodulatorsandfournarrowbandphotodetectorsintheproposedschemeareused.OneadvantageofourschemeisthatnoBell-statemeasurementisneedandnoanyunitarytransformationisperformed.
简介:TheHamiltonianformulationsofthelinear'good'Boussinesq(L.G.B.)equationandthemulti-symplecticformulationofthenonlinear'good'Boussinesq(N.G.B.)equationareconsidered.Forthemulti-symplecticformulation,anewfifteen-pointdifferenceschemewhichisequivalenttothemulti-symplecticPreissmannintegratorisderived.Wealsopresentnumericalexperiments,whichshowthatthesymplecticandmultisymplecticschemeshaveexcellentlong-timenumericalbehavior.
简介:Thecompressedsensing(CS)ofaccelerationdatahasbeendrawingincreasingattentioningaittelemonitoringapplication.Insuchapplication,therestillexistsomechallengingissuesincludinghighenergyconsumptionofbody-worndeviceforaccelerationdataacquisitionandthepoorreconstructionperformanceduetononsparsityofaccelerationdata.Thus,thenovelschemeofcompressivesensingofaccelerationdataisneededurgentlyforsolutionsthatarefoundtotheseissues.
简介:Spectrumsensingisoneofthecoretechnologiesforcognitiveradios(CR),wherereliabledetectionofthesignalsofprimaryusers(PUs)ispreconditionforimplementingtheCRsystems.AcooperativespectrumsensingschemebasedonanadaptivedecisionfusionalgorithmforspectrumsensinginCRisproposedinthispaper.ThisschemecanestimatethePUpriorprobabilityandthemissdetectionandfalsealarmprobabilitiesofvarioussecondaryusers(SU),andmakethelocaldecisionwiththeChair-Varshneyrulesothatthedecisionsfusioncanbedonefortheglobaldecision.SimulationresultsshowthatthefalsealarmandmissdetectionprobabilitiesresultedfromtheproposedalgorithmaresignificantlylowerthanthoseofthesingleSU,andtheperformanceoftheschemeoutperformsthatofthecooperativedetectionbyusingtheconventionaldecisionfusionalgorithms.
简介:Anewalternatingdirection(AD)finiteelement(FE)schemefor3-dimensionalnonlinearparabolicequationandparabolicintegro-differentialequationisstudied.ByusingAD,the3-dimensionalproblemisreducedtoafamilyofsinglespacevariableproblems,calculationworkissimplified;byusingFE,highaccuracyiskept;byusingvarioustechniquesforprioriestimatefordifferentialequationssuchasinductivehypothesisreasoning,thedifficultyarisingfromthenonlinearityistreated.ForbothFEandADFEschemes,theconvergencepropertiesarerigorouslydemonstrated,theoptimalH1-andL2-normspaceestimatesandtheO((△t)2)estimatefortimevariableareobtained.
简介:Anewfairoff-lineelectroniccashschemeonellipticcurvecryptographywaspresented.Thenewschemeismoreefficientthanthosebyextendingfairoff-lineelectroniccashschemefromfinitefieldintoellipticcurvecryptographyandintroducinganewellipticcurvediscretelogarithmassumption.Theexpirydateanddenominationareembeddedintotheblindlysignedcoinbyintegratingpartiallyblindsignaturewithrestrictiveblindsignature.Abankneednotusedifferentpublickeysfordifferentcoinvalues,shopsandusersneednotcarryalistofbank'spublickeystoverifyintheirelectronicwallet.Atthesametime,thebankjustneedstokeepundueelectroniccoinsfordoublespendingcheckinhisdatabase,thusbank'sdatabasecanbedramaticallyreduced.
简介:AllwatermarksaresharedintoshadowimagesusingVCS(VisualCryptographyScheme).Onlyonespecificshadow(asanewwatermark)isembeddedintothehostsignalandtheotheronesaredistributedtoeveryuserineachgroupasakey.Inthewatermarkingextractionprocedure,usersindifferentgroupcanobtaindifferentwatermarkbycombiningtheirshadowswiththeextractedonefromthewatermarkedsignal.Analysisandexperimentalresultsshowthatthenewwatermarkingmethodisnovel,secureandrobust.
简介:TheuseoftheLaserMegaJoulefacilitywithintheshockignitionschemehasbeenconsidered.Inthefirstpartofthestudy,one-dimensionalhydrodynamiccalculationswereperformedforaninertialconfinementfusioncapsuleinthecontextoftheshockignitionschemeprovidingtheenergygainandanestimationoftheincreaseofthepeakpowerduetothereductionofthephotonpenetrationexpectedduringthehigh-intensityspikepulse.Inthesecondpart,weconsideredaLaserMegaJouleconfigurationconsistingof176laserbeamsthathavebeengroupedprovidingtwodifferentirradiationschemes.Inthisconfigurationthemaximumavailableenergyandpowerare1.3MJand440TW.Optimizationofthelaser–capsuleparametersthatminimizetheirradiationnon-uniformityduringthefirstfewnsofthefootpulsehasbeenperformed.ThecalculationstakeintoaccountthespecificellipticallaserintensityprofileprovidedattheLaserMegaJouleandtheexpectedbeamuncertainties.Asignificantimprovementoftheilluminationuniformityprovidedbythepolardirectdrivetechniquehasbeendemonstrated.Three-dimensionalhydrodynamiccalculationshavebeenperformedinordertoanalysethemagnitudeoftheazimuthalcomponentoftheirradiationthatisneglectedintwodimensionalhydrodynamicsimulations.
简介:ThispaperpresentsasimpleandrobustspeedcontrolschemeofPermanentMagnetSynchronousMotor(PMSM).Itistoachieveaccuratecontrolpeffommancemthepresenceofloadtorqueandplantparametervariation.Arobustdisturbancecancellationfeedforwardcontrollerisusedtoestimatethetorquedisturbance.ThesimpleandpracticalcontrolschemeiseasilyimplementedonaPMSMdriverusingaTMS320LF2407DSP.Theeffectivenessoftheproposedrobustspeedcontrolapproachisdemonstratedbysimulationandexperimentalresults.
简介:Afamilyofarraycodeswithamaximumdistanceseparable(MDS)property,namedLcodes,isproposed.ThegreateststrengthofLcodesisthatthenumberofrows(columns)inadiskarraydoesnotberestrictedbytheprimenumber,andmorediskscanbedynamicallyappendedinarunningstoragesystem.Lcodescantolerateatleasttwodiskerasuresandsomesectorlosssimultaneously,andcantoleratemultiplediskerasures(greaterthanorequaltothree)underacertaincondition.BecauseonlyXORoperationsareneededintheprocessofencodinganddecoding,LcodeshaveveryhighcomputingefficiencywhichisroughlyequivalenttoXcodes.AnalysisshowsthatLcodesareparticularlysuitableforlarge-scalestoragesystems.
简介:AFourierspectralschemeisproposedforsolvingtheperiodicproblemofnonlinearKlein-Gordonequation.Itsstabilityandconvergenceareinvestigated.Numericalresultsarealsopresented.
简介:Thispaperconsiderstheone-dimensionaldissipativecubicnonlinearSchrdingerequationwithzeroDirichletboundaryconditionsonaboundeddomain.Theequationisdiscretizedintimebyalinearimplicitthree-levelcentraldifferencescheme,whichhasanalogousdiscreteconservationlawsofchargeandenergy.Theconvergencewithtwoordersandthestabilityoftheschemeareanalysedusingaprioriestimates.Numericaltestsshowthatthethree-levelschemeismoreefficient.