简介:Inthispaperamodeloftransvcrsalfilterispresentedtostudytheadaptivematchofthetimevariantchannel.Theleastmeansquareerrorfil-teringmethodisusedtoobtaintheweightingcoeffcientsofthefilter.Withthepurposeofspeedinguptheconvergenceoftheiterationequationofadaptivefiltering,anadaptivefactoroftheiterationstepsizeμ_aisderivedinthispaper.Theresultofcomputersimulationshowsthatinthecaseofusingadaptiveμ_a,theconvergencespeedoftheiterationequationisincreased2timesapproximatelyincomparisonwithconstantμ_f.Thestudysuggeststhattheadaptivefilterwithadaptiveμ_a.havetheperformancetofollowthechangeoftime-variantcharacteristicsofthechannel.
简介:Anadaptivealgorithmforsolvinglargenonsymmetriclinearsystemsispresentedinthispaper.ThenewalgorithmcombinespolynomialpreconditioningtechniquewiththeCGNRmethod.Residualpolynomialisusedinthepreconditioningtoestimatetheeigenvaluesofthes.p.d.matrixArA,andtheresidualpolynomialisgeneratedfromseveralstepsofCGNRbyrecurrence.Thealgorithmisadaptiveduringitsimplementation.Therobustnessismaintained,andtheiterationconvergenceisspeededup.Twonumericaltestresultsarealsoreported.
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简介:Responseofadaptivematchedfilter,alsocalledadaptivecorrelator,tomultipathchannelisdiscussedinthispaper.Ithasbeenprovedthatthenewtypeprocessorcanbettermatchwithmultipathchan-nel.Theresultsofexperimentcarriedoutonlakeandinlaboratoryarepresented.Itshowsthattheprocessorhasgooddetectingperformanceintimedomain.
简介:Thispaperdescribestheinverstigationdevotedtoestablishsuitableweightsinafeed-forwardneuralnetworkrealizingthenarrow-bandfilteringmapinthecaseofadaptivelineenhancement(ALE)bytheutilityoftheoptimumcommonlearningratebackpropagation(OCLRBP)algorithm.Itisfoundthatafeed-forwardnetworkwith64linearinputandoutputneurons,and8oddsigmoidneuronsinthehiddenlayer,i.e.an(64→8→64)architecture,couldestablishthespecificinput-outputfunctioninthecaseofrelativelylowsignal-to-noiseradio.Onlyisaninputsignalconsistingofmixedperiodicandbroad-bandcomponentsavailabletothenetworksystem.Afterlearning,boththe"fanning-in-connectionpatterns",eachofwhichconsistsofweightsfanningintoahidden-neuronFromalltheoutputsofinput-neurons,andthe"fanning-out-connectionpatterns",eachofwhichconsistsofweightsfanningoutfromahidden-neurontoalltheinputsofoutput-neurons,aretunedtotheperiodicsignals.Thenonline
简介:SHELLADAPTIVETRIANGULATIONOFTRIMMEDNURBSSURFACEWangHuichengZhangXinfangZhouJiAbstractThepaperpresentsanewapproachfortriangula...
简介:Thispaperpresentanimprovedpreciseintegrationalgorithmfortransientanalysisofheattransferandsomeotherproblems.Theoriginalpreciseintegrationmethodisimprovedbymeanoftheinve-rseaccuracyanalysissothattheparameterN,whichhasbeentakenasaconstantandanindependentpa-rameterwithoutconsiderationoftheproblemsintheoriginalmethod,canbegeneratedautomaticallybythealgorithmitself.Thus,theimprovdealgorithmisadaptiveandtheaccucacyofthealgorithmisnotdependentonthelengthofthetimestepintheintegrationprocess.Itisshownthatthenumericalresultsobtainedbythemethodproposedaremoreaccuratethanthoseobtainedbytheconventionaltimeintegrationmethodssuchasthedifferencemethodandothers.Fourexamplesaregiventodemonstratethevalidity,accuracyandeffi-ciencyofthenewmethod.
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简介:FortheARMAXsystemwithunknowncoefficientstheoptimaladaptivecontrolisdesignedsothatthefollowingrequirementsaremetsimultaneously:1)thetransferfunctionfromareferencesignaltothesystemoutputintheclosedloopequalsaprescribedrationalfunction;2)undertheconstraintmentionedin1)aquadraticlossfunctionisminimized;3)theparameterestimateisstronglyconsistent.
简介:ThispaperpresentsapragmaticadaptiveschemeforTuCMoverslowlyfadingchannels.Theadaptiveschemeemploysasingleturbocodedmodulatorcomposedofavariable-rateturboencoderandavariable-ratevariable-powerMQAMforallfadingregions,soithasanacceptablecomplexitytoimplement.TheoptimaladaptiveTuCMschemeisdeterminedsubjecttovarioussystemconstraints.Simulationshavebeenperformedtomeasuretheperformanceoftheschemefordifferentparameters.Itisshownthatadoptingboththeturbocodedmodulatorandthetransmitpowerachievesaperformancewithin2.5dBofthefadingchannelcapacity.
简介:Anewadaptivetechniqueofr-andh-versionforvibrationproblemsutilizingthematrixper-turbationtheoryandelementenergyratioisproposed.Instructuralvibrationanalysis,throughther-conver-genceadaptivefiniteelementprocess,meshoptimizationcanberealized.Inthelightofthejudgementonthechangesinthemagnitudeoftheelementenergyratio,localrefinementcanbeachievedintheprocessofh-convergenceadaptivefiniteelementsothatmoreaccuratefiniteelementsolutionscanbeobtainedwithasfewmeshesaspossible.Manynumericalexamplesaregivenandtheproposedapproachisshowntobefeasibleandeffective.
简介:Totacklemulticollinearityorill-conditioneddesignmatricesinlinearmodels,adaptivebiasedestimatorssuchasthetime-honoredSteinestimator,theridgeandtheprincipalcomponentestimatorshavebeenstudiedintensively.Tostudywhenabiasedestimatoruniformlyoutperformstheleastsquaresestimator,somesufficientconditionsareproposedintheliterature.Inthispaper,weproposeaunifiedframeworktoformulateaclassofadaptivebiasedestimators.Thisclassincludesallexistingbiasedestimatorsandsomenewones.Asufficientconditionforoutperformingtheleastsquaresestimatorisproposed.Intermsofselectingparametersinthecondition,wecanobtainalldouble-typeconditionsintheliterature.
简介:Supplychainisacomplex,hierarchical,integrated,openanddynamicnetwork.Everynodeinthenetworkisanindependentbusinessunitthatunitesotherorganizationstodevelopitsvalue,thecompetitionandcooperationbetweentheseunitsarebasicimpetusofthedevelopmentandevolutionofthesupplychainsystem.Thecharacteristicsofsupplychainasacomplexadaptivesystemanditsmodelingarediscussedinthispaper,anduseanexampledemonstratingthefeasibilityofCASmodelinginsupplychainmanagementstudy.
简介:Inthispaper,atrustregionmethodforequalityconstrainedoptlmizationbasedonnondiferentiableexactpenaltyisproposed.Inthisalgorithin,thetrailstepischaracterizedbycomputationofitsnormalcomponentbeingseparatedfromcomputationofitstangentialcomponent,i.e.,onlythetangentialcomponentofthetrailstepisconstrainedbytrustradiuswhilethenormalcomponentandtrailstepitselfhavenoconstraints.Theothermaincharacteristicofthealgorithmisthedecisionoftrustregionradius.Here,thedecisionoftrustregionradiususestheinformationofthegradientofobjectivefunctionandreducedHessian.However,Maratoseffectwilloccurwhenweusethenondifferentiableexactpenaltyfunctionasthemeritfunction.Inordertoobtainthesuperlinearconvergenceofthealgorithm,weusethetwiceordercorrectiontechnique.Becauseofthespecialityoftheadaptivetrustregionmethod,weusetwiceordercorrectionwhenp=0(thedefinitionisasinSection2)andthisisdifferentfromthetraditionaltrustregionmethodsforequalityconstrainedopthnization.Sothecomputationofthealgorithminthispaperisreduced.Whatismore,wecanprovethatthealgorithmisgloballyandsuperlinearlyconvergent.
简介:Optimisingbothqualitativeandquantitativefactorsisakeychallengeinsolvingconstructionfinancedecisions.Thesemi-structurednatureofconstructionfinanceoptimisationproblemsprecludesconventionaloptimisationtechniques.Withadesiretoimprovetheperformanceofthecanonicalgeneticalgorithm(CCA)whichischaracterisedbystaticcrossoverandmutationprobability,andtoprovidecontractorswithaprofit-risktrade-offcurveandcashflowprediction,anadaptivegeneticalgorithm(AGA)modelisdeveloped.TenprojectsbeingundertakenbyamajorconstructionfirminHongKongwereusedascasestudiestoevaluatetheperformanceofthegeneticalgorithm(CA).TheresultsofcasestudyrevealthattheACAoutperformedtheCGAbothintermsofitsqualityofsolutionsandthecomputationaltimerequiredforacertainlevelofaccuracy.TheresultsalsoindicatethatthereisapotentialforusingtheGAformodellingfinancialdecisionsshouldbothquantitativeandqualitativefactorsbeoptimisedsimultaneously.
简介:Weconsiderinthispapertheproblemofrecursiveidentificationforstochasticsystemswhenthenoisemodeldoesnotsatisfythepositiverealconditionassociatedwithconvergenceofstandardalgorithms.Toavoidthepositiverealcondition,adaptivespectralfactorizationtechniquesareexploitedonthebasisofaclassofnon-standardtime-varyingrecursiveRiccatiequations.TheasymptoticpropertiesoftheRiccatiequationsarestudiedasacrucialsteptotheconvergenceresultsofthepaper.