简介：Thispaperpresentsanewmethodforresynchronizationattack,whichisthecombinationofthedifferentialcryptanalysisandalgebraicattack.Byusingthenewmethodonegetsasystemoflinearequationsorlow-degreeequationsaboutinitialkeys,andthesolutionofthesystemofequationsresultsintherecoveryoftheinitialkeys.Thismethodhasalowercomputationalcomplexityandbetterperformanceofattackincontrasttotheknownmethods.Accordingly,thedesignoftheresynchronizationstreamgeneratorsshouldbereconsideredtomakethemstrongenoughtoavoidourattacks.WhenimplementedtotheToyocrypt,ourmethodgainsthecomputationalcomplexityofO(217),andthatofO(267)forLILI-128.
简介：Anewiterativemethodforsignal,restorationhasbeenpresented.AnestimateoperatorW_κwhichisrelatedtoerroroperatorB_κintherestorationprocessisintroducedtodecreasetheestimateerrorandincreasetheconvergencerate.Theeffectofnoiseontheestimateprocesshasalsobeendescribed.Finally,themethodhasbeenappliedtothedeconvolutionofablurredsignal,andtheresultsvalidatethemethod.Acomparisonbetweenthepresentedmethodandthegeneralmethodhasalsobeengiven.
简介：Aprecisetwo-degree-of-freedommeasuringsystem(2DMS)isdevelopedbasedonsingle-modeopticalfiber,LD,cubecornerretroreflectorandfour-quadrantphotodetector(4-Q),andthesimultaneouson-linemeasurementoflateralandverticaldirectionstraightnesserrorsofthelinearstageiscarriedout.Themovingpartiswireless,whicheliminatesanyerrorsintroducedbypushingandpullingthewires.Thesensitivityofthestraightnesserrormeasurementcanbeimprovedbyafactorof2withthecubecornerretroreflector.Thisfiber-basedopticallyalignedbeamisusedtoestablishareferencelineforthestraightnessmeasurementofanymechanicalsystem.4-Qdetectorisusedtoreceivethelaserbeam.Achipmicrocomputerisdevelopedtoconductalldataacquisitionandsignalprocessing.Thebeamdriftinfluencecanberemovedinthegreatestextentfromthesystem.Theexperimentsonthemeasurementsystemstability,repeatabilityanditscomparisonwiththeHP5528double-frequencylaserinterferometerarecarriedout.
简介：Basedonuniformcirculararrayanditselementoutputsignaldelaydelayanovelmethodforestimationofspatialfrequency,azimuthandelevationispresented.Withoutanyspectralpeaksearchandparameterspairing,theresultingmethodis(?)resolutionandsmallvariance,eveninshortdatalength.Computersimulation(?)effectivenessofthismethod.
简介：Ageonetricalmoirémethodfordisplayingdirectlyisochromaticsandisoclinicsofadiametricallypressedcirculardiskispresented.ItisdemonstratedthatbyusingtwoidenticalordifferentWulffnets(orgrids)notonlythestressfieldsofacirculardiskcanbedisplayed,buttheu-andv-displacementfieldscanalsobeproduced.
简介：Thedatausedintheprocessofknowledgediscoveryoftenincludesnoiseandincompleteinformation.Theboundariesofdifferentclassesofthesedataareblurandunobvious.Whenthesedataareclusteredorclassified,weoftengetthecoveringsinsteadofthepartitions,anditusuallymakesourinformationsysteminsecure.Inthispaper,optimalpartitioningofincompletedataisresearched.Firstly,therelationshipofsetcoverandsetpartitionisdiscussed,andthedistancebetweensetcoverandsetpartitionisdefined.Secondly,theoptimalpartitioningofgivencoverisresearchedbythecombingandpartingmethod,acquiringtheoptimalpartitionfromthreedifferentpartitionssetfamilyisdiscussed.Finally,thecorrespondingoptimalalgorithmisgiven.Therealwirelesssignalsofftencontainalotofnoise,andtherearemanyerrorsinboundarieswhenthesedataisclusteredbasedonthetradionalmethod.Inourexperimant,theproposedmethodimprovescorrectrategreatly,andtheexperimentalresultsdemonstratethemethod’svalidity.
简介：Inthispaper,alowcomplexityESPRITalgorithmbasedonpowermethodandOrthogo-nal-triangular(QR)decompositionispresentedfordirectionfinding,whichdoesnotrequireaprioriknowledgeofsourcenumberandthepredeterminedthreshold(separatesthesignalandnoiseei-gen-values).Firstly,accordingtotheestimationofnoisesubspaceobtainedbythepowermethod,anovelsourcenumberdetectionmethodwithouteigen-decompositionisproposedbasedonQRde-composition.Furthermore,theeigenvectorsofsignalsubspacecanbedeterminedaccordingtoQmatrixandthenthedirectionsofsignalscouldbecomputedbytheESPRITalgorithm.Todeterminethesourcenumberandsubspace,thecomputationcomplexityoftheproposedalgorithmisapproximatedas(2log_2n+2.67)M~3,wherenisthepowerofcovariancematrixandMisthenumberofarrayele-ments.ComparedwiththeSingleVectorDecomposition(SVD)basedalgorithm,ithasasubstantialcomputationalsavingwiththeapproximationperformance.Thesimulationresultsdemonstrateitseffectivenessandrobustness.
简介：Thispaperproposesanovelexemplar-basedmethodforreducingnoiseincomputedtomography(CT)images.Intheproposedmethod,denoisingisperformedoneachblockwiththehelpofagivendatabaseofstandardimageblocks.Foreachnoisyblock,itsdenoisedversionisthebestsparsepositivelinearcombinationoftheblocksinthedatabase.Weformulatetheproblemasaconstrainedoptimizationproblemsuchthatthesolutionisthedenoisedblock.Experimentalresultsdemonstratethegoodperformanceoftheproposedmethodovercurrentstate-of-the-artdenoisingmethods,intermsofbothobjectiveandsubjectiveevaluations.
简介：Inthispaper,thesubspacefittingmodelsfordirection-of-arrival(DOA)estimationisanalyzed,aneffectivealgorithmicapproachisgiven.Astheinitializationvalueissocriticaltotheglobalconvergence,thecontinuationtheoryisalsousedtodevelopanewframeworkwhichsolvestheinitializationproblempowerfully.Somenumericalevidencewillbegiventoshowthattheperformanceofthenewalgorithmisverypromising.
简介：Severalmethodsforinvestigatingthethicknessuniformityofpolymerthinfilmsarepresentedaswellastheirmeasurementprinciples.Acomparisonoftheseexperimentalmethodsisgiven.Thecylindricallightwavereflectionmethodisfoundtocanobtainthethicknessdistributionalongacertaindirection.Itisasimpleandsuitablemethodtoevaluatethefilmthicknessuniformity.
简介：Deadlockmustbeavoidedinamanufacturingsystem.Inthispaper,anefficientalgorithmforfindinganoptimaldeadlock-freeschedulesinamanufacturingsystemwithverylimitedbufferispresented.Thisalgorithmisbasedonheeffectivegeneticalgorithm(GA)searchmethod,andaformalPetrinetstructureisintroducedtodetectthetokenplayerassuringdeadlock-free.InordertomaketheschedulingstrategygeneratedbyGAmeettherequiredconstraintofdeadlock-free,someresultsofthestruetureanalysisofPetrinetareinvolvedasacriteriontoselectdeadlock-freeschedulefromthepopulationgeneratedbyGA.Theeffectivenessandefficiencyoftheproposedapproachisillustratedbyusinganexample.
简介：Thecoreofnetworksecurityistheriskassessment.Inthisletter,ariskassessmentmethodisintroducedtoestimatethewirelessnetworksecurity.Themethod,whichcombinesAnalyticHier-archyProcess(AHP)methodandfuzzylogicalmethod,isappliedtotheriskassessment.Fuzzylogicalmethodisappliedtojudgetheimportantdegreeofeachfactorintheaspectsoftheprobability,theinfluenceandtheuncontrollability,nottodirectlyjudgetheimportantdegreeitself.Theriskas-sessmentiscarvedup3layersapplyingAHPmethod,thesortweightofthethirdlayeriscalculatedbyfuzzylogicalmethod.Finally,theimportantdegreeiscalculatedbyAHPmethod.Bycomparingtheimportantdegreeofeachfactor,theriskwhichcanbecontrolledbytakingmeasuresisknown.Thestudyofthecaseshowsthatthemethodcanbeeasilyusedtotheriskassessmentofthewirelessnetworksecurityanditsresultsconformtotheactualsituation.
简介：TheBi-LSmethodbasedonQRdecompositionprovidesaconvenientframeworkforde-velopingefficientsubspacetrackingalgorithms.ToovercometheshortcomingofthebacksubstitutionstepandimprovetheparallelarchitectureoftheBi-LSalgorithms,aBi-LSsubspacetrackingalgorithmbasedonInverseQR(IQR)decompositionisdeveloped.TheproposedIQRiterativealgorithmforsubspacetrackingiswellsuitedfortheparallelimplementationinthesystolicarray.SimulationresultsarepresentedtoillustratetheeffectivenessoftheproposedIQRsubspacetrackingalgorithm.
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