简介:Aclassoflarge-sealesystems,wheretheoverallobjectivefunctionisanonlinearfunctionofperformanceindexofeachsubsystem,isinvestigatedinthispaper.Thistypeoflarge-scalecontrolproblemisnon-separableinthesenseofconventionalhierarchicalcontrol.Hierarchicalcontrolisextendedinthepapertolarge-scalenon-separablecontrolproblems,wheremultiobjectiveoptimizationisusedasseparationstrategy.Thelarge-scalenon-separablecontrolproblemisembedded,under;ertainconditions,intoafamilyoftheweightedLagrangianformulation.TheweightedLagrangianformulationisseparablewithrespecttosubsystemsandcanbeeffectivelysolvedusingtheinteractionbalanceapproachatthetwolowerlevelsintheproposedthree-levelsolutionstructure.Atthethirdlevel,theweightingvectorfortheweightedLagrangianformulationisadjustediterativelytosearchtheoptimalweightingvectorwithwhichtheoptimaloftheoriginallarge-scalenon-separablecontrolproblemisobtained.Theoreticalbaseofthealgorithmisestablished.Simulationshowsthatthealgorithmiseffective.
简介:Watershedtransformationisapowerfulmorphologicaltoolimagesegmentation.However,theperformanceoftheimagesegmentationmethodsbasedonwatershedtransformationdependslargelyonthealgorithmforcomputingthegradientoftheimagetobesegmented.Inthispaper,wepresentamulti-scalegradientalgorithmbasedonmorphologicalopenatorsforwatershed-basedimagesegmentation,witheffectivehandlingofbothstepandblurrededges.Wealsopresentanalgorithmtoeliminatethelocalminimaproducedbynoiseandquantizationerrors.Experimentalresultsindicatethatwatershedtransformationwiththealgorithmsproposedinthispaperproducesmeaningfulsegmentations,evenwithoutaregion-mergingstep.
简介:Asimplecriterionfordelay-independentstabilityoflarge-scalelineartime-varyingsystemsisdeducedbyemployingatypeofLyapunoyfunction.Thenotablefeaturesoftheresultsinthispaperareitssimplicityandefficiencyintestingthestabilitylarge-scalelineartime-varyingsystems.Someillustrativeexamplesaregiventodemonstratetheadvantagesoftheobtainedresultsoverthoseinliterature.
简介:Afamilyofarraycodeswithamaximumdistanceseparable(MDS)property,namedLcodes,isproposed.ThegreateststrengthofLcodesisthatthenumberofrows(columns)inadiskarraydoesnotberestrictedbytheprimenumber,andmorediskscanbedynamicallyappendedinarunningstoragesystem.Lcodescantolerateatleasttwodiskerasuresandsomesectorlosssimultaneously,andcantoleratemultiplediskerasures(greaterthanorequaltothree)underacertaincondition.BecauseonlyXORoperationsareneededintheprocessofencodinganddecoding,LcodeshaveveryhighcomputingefficiencywhichisroughlyequivalenttoXcodes.AnalysisshowsthatLcodesareparticularlysuitableforlarge-scalestoragesystems.
简介:Anovelandefficientmethodfordecomposingasignalintoasetofintrinsicmodefunctions(IMFs)andatrendisproposed.Unliketheoriginalempiricalmodedecomposition(EMD),whichusessplinefitstoextractvariationsfromthesignalbyseparatingthelocalmeanfromthefluctuationsinthedecomposingprocess,thisnewmethodbeingproposedtakesadvantageofthetheoryofvariablefiniteimpulseresponse(FIR)filteringwherefiltercoefficientsandbreakpointfrequenciescanbeadjustedtotrackanypeak-to-peaktimescalechanges.TheIMFsateresultsofamultiplevariablefrequencyresponseFIRfilteringwhensignalspassthroughthefilters.Numericalex-amplesvalidatethatincontrastwiththeoriginalEMD,theproposedmethodcanfine-tunethefrequencyresolutionandsuppressthealiasingeffectively.
简介:Anadaptivedigitalimagewatermarkalgorithmwithstrongrobustnessbasedongray-scalemorphologyisproposedinthispaper.Theembeddedstrategiesinclude:Thealgorithmseeksandextractsadaptivelytheimagestrongtextureregions.Thealgorithmmapstheimagestrongtextureregiontothewavelettreestructures,andembedsadaptivelywatermarkintothewaveletcoefficientscorrespondingtotheimage'sstrongtextureregions.Accordingtothevisualmaskingfeatures,thealgorithmadjustsadaptivelythewatermark-embeddingintensity.Experimentalresultsshowthealgorithmisrobusttocompression,filtering,noiseaswellasstrongshearattacks.Thealgorithmisblindwatermarkscheme.Theimagestrongtextureregionextractionmethodbasedonmorphologyinthisalgorithmissimpleandeffectiveandadaptivetovariousimages.
简介:De-duplicationusingbiometricshasgainedmuchattentionfromresearchcommunitiesasitprovidesauniqueidentityforeachandeveryindividualamongthelargepopulation.De-duplicationistheprocessofremovingtheinstancesofmultipleenrollmentsbythesamepersonusingtheperson’sbiometricdata.Animportantissueinthelarge-scalede-duplicationapplicationsisthespeedofmatchingandtheaccuracyofthematchingbecausethenumberofpersonstobeenrolledrunsintomillions.Thispaperpresentsanefficientmethodtoimprovetheaccuracyoffingerprintde-duplicationinde-centralizedmanner.De-duplicationaccuracydecreasesbecauseofthenoisepresentinthedata,whichwouldcauseimproperslapfingerprintsegmentation.Inthispaper,anattemptismadetoremovethenoisepresentinthedatabyusingbinarizationofslapfingerprintimagesandregionlabelingofdesiredregionswith8-adjacencyneighborhood.Thedistinctfeatureofthistechniqueistoremovethenoisepresentinthedataforanaccurateslapfingerprintsegmentationandimprovethede-duplicationaccuracy.Experimentalresultsdemonstratethatthefingerprintsegmentationrateandde-duplicationaccuracyareimprovedsignificantly.
简介:UnderstandingtheNatureofPredatoryPriciginLarge-ScaleMarketEconomywithGeneticAlgorithmsTXUnderstandingtheNatureofPredatoryPrici...
简介:Theproblemofpartialstabilityisinvestigatedforaclassofcontinuous-timelarge-scalesystems.Underassumptionthatthenullsolutionoftheisolatedsubsystemsisstable,basedondecomposition-aggregationmethodsandLyapunovsecondmethod,sometheoremsconcerningthegloballypartialasymptoticstabilityandgloballypartialexponentialstabilityareobtainedviautilizingtheinequalityanalysistechniqueandcomparisontechnique.Finally,anexampleispresentedtoillustratetheresults.
简介:Inthispaper,wepresentarobotvisionbasedsystemforcoordinatemeasurementoffeaturepointsonlargescaleautomobileparts.Oursystemconsistsofanindustrial6-DOFrobotmountedwithaCCDcameraandaPC.Thesystemcontrolstherobotintotheareaoffeaturepoints.Theimagesofmeasuringfeaturepointsareacquiredbythecameramountedontherobot.3Dpositionsofthefeaturepointsareobtainedfromamodelbasedposeestimationthatappliestotheimages.Themeasuredpositionsofallfeaturepointsarethentransformedtothereferencecoordinateoffeaturepointswhosepositionsareobtainedfromthecoordinatemeasuringmachine(CMM).Finally,thepoint-to-pointdistancesbetweenthemeasuredfeaturepointsandthereferencefeaturepointsarecalculatedandreported.Theresultsshowthattherootmeansquareerror(RMSE)ofmeasurevaluesobtainedbyoursystemislessthan0.5mm.Oursystemisadequateforautomobileassemblyandcanperformfasterthanconventionalmethods.
简介:Aimingattheconceptof'diagnosis',asimpleandeffectivebroadbandradarcrosssection(RCS)measurementsystemisconstructed,andsomemulti-dimensionalscatteringpropertiesdiagnosistechniquesarepresentedbasedonthesystem.Firstly,astepped-frequencysignalisemployedtoachievehighrangeresolution,combiningwithavarietyofsignalprocessingtechniques.Secondly,cross-rangeresolutionisgainedwitharotatingtable,andthehigh-resolutiontwo-dimensional(2-D)imagingofthescalemodelisobtainedbythemicrowaveimagingtheory.Finally,tworeceivingantennaswithasmalldistanceinaltitudeareused,andthethree-dimensional(3-D)heightdistributionofscatteringpointsonthescalemodelisextractedfromthephaseofimages.Sometypicalbodiesandascaleaircraftmodelarediagnosedinananechoicchamber.Theexperimentalresultsshowthat,afterscalingwithametalsphere,theaccurateonedimensional(1-D)RCSpatternofthemodelisobtained,andithasalargedynamicrange.Whenthebandwidthofthetransmittingsignalis4GHz,theresolutionofthe2-Dimagecanreachto0.0375m.The3-Dheightdistributionofscatteringpointsisgivenbyinterferometricmeasurement.Thispaperprovidesafeasiblewaytoobtainhigh-precisionscatteringpropertiesparametersofthescaleaircraftmodelinaconventionalrectangularanechoicchamber.
简介:Howtoeffectivelyreducetheenergyconsumptionoflarge-scaledatacentersisakeyissueincloudcomputing.Thispaperpresentsanovellow-powertaskschedulingalgorithm(LTSA)forlarge-scaleclouddatacenters.Thewinnertreeisintroducedtomakethedatanodesastheleafnodesofthetreeandthefinalwinneronthepurposeofreducingenergyconsumptionisselected.Thecomplexityoflarge-scaleclouddatacentersisfullyconsider,andthetaskcomparsoncoefficientisdefinedtomaketaskschedulingstrategymorereasonable.Experimentsandperformanceanalysisshowthattheproposedalgorithmcaneffectivelyimprovethenodeutilization,andreducetheoverallpowerconsumptionoftheclouddatacenter.
简介:Asimplemethodtofabricateone-dimensional(1-D)andtwo-dimensional(2-D)orderedmicro-andnano-scalepatternsisdevelopedbasedontheoriginalmastersfromopticaldiscs,usingnanoimprinttechnologyandsoftstamps.Polydimethylsiloxane(PDMS)wasusedtoreplicatethenegativeimageofthe1-DgratingpatternonthemastersofCD-R,DVD-RandBD-Ropticaldiscs,respectively,andthenthe1-DpatternononeofthePDMSstampswastransferredtoablankpolycarbonate(PC)substratebynanoimprint.The2-DorderedpatternswerefabricatedbythesecondimprintingusinganotherPDMSstamp.Different2-DperiodicpatternswereobtaineddependingonthePDMSstampsandtheanglebetweenthetwotimesofimprints.Thismethodmayprovideawayforthefabricationofcomplex2-Dpatternsusingsimple1-Dmasters.
简介:Average(mean)voterisoneofthecommonestvotingmethodssuitablefordecisionmakinginhighly-availableandlong-missionsapplicationswheretheavailabilityandthespeedofthesystemarecritical.Inthispaper,anewgenerationofaveragevoterbasedonparallelalgorithmsandparallelrandomaccessmachine(PRAM)structureareproposed.Theanalysisshowsthatthisalgorithmisoptimalduetoitsimprovedtimecomplexity,speed-up,andefficiencyandisespeciallyappropriateforapplicationswherethesizeofinputspaceislarge.
简介:Amodifiedbottleneck-based(MB)heuristicforlarge-scalejob-shopschedulingproblemswithawell-definedbottleneckissuggested,whichissimplerbutmoretailoredthantheshiftingbottleneck(SB)procedure.Inthisalgorithm,thebottleneckisfirstscheduledoptimallywhilethenon-bottleneckmachinesaresubordinatedaroundthesolutionsofthebottleneckschedulebysomeeffectivedispatchingrules.ComputationalresultsindicatethattheMBheuristiccanachieveabettertradeoffbetweensolutionqualityandcomputationaltimecomparedtoSBprocedureformedium-sizeproblems.Furthermore,itcanobtainagoodsolutioninashorttimeforlarge-scalejob-shopschedulingproblems.
简介:Fromtheperspectiveofcompressedsensing(CS)theory,thechannelestimationprobleminlarge-scalemultipleinputmultipleoutput(MIMO)-orthogonalfrequencydivisionmultiplexing(OFDM)systemisinvestigated.Accordingtothetheory,thesmallermutualcoherencethereconstructionmatrixhas,thehighersuccessprobabilitytheestimationcanobtain.Aimingtodesignapilotthatcanmakethesystemreconstructionmatrixhavingthesmallestmutualcoherence,thispaperproposesalowcomplexityjointalgorithmandobtainsakindofnon-orthogonalpilotpattern.Simulationresultsshowthatcomparedwiththeconventionalorthogonalpilotpattern,applyingtheproposedpatternintheCSchannelestimationcanobtainthebetternormalizedmeansquareerrorperformance.Moreover,thebiterrorrateperformanceofthelarge-scaleMIMO-OFDMsystemisalsoimproved.
简介:Theproblemofadaptivefuzzycontrolforaclassoflarge-scale,time-delayedsystemswithunknownnonlineardead-zoneisdiscussedhere.Basedontheprincipleofvariablestructurecontrol,adesignschemeofadaptive,decentralized,variablestructurecontrolisproposed.Theapproachremovestheconditionsthatthedead-zoneslopesandboundariesareequalandsymmetric,respectively.Inaddition,itdoesnotrequirethattheassumptionsthatallparametersofthenonlineardead-zonemodelandthelumpeduncertaintyareknownconstants.Theadaptivecompensationtermsoftheapproximationerrorsareadoptedtominimizetheinfluenceofmodelingerrorsandparameterestimationerrors.Bytheoreticalanalysis,theclosed-loopcontrolsystemisprovedtobesemi-globallyuniformlyultimatelybounded,withtrackingerrorsconvergingtozero.Simulationresultsdemonstratetheeffectivenessoftheapproach.