简介:Apowerallocationschemeformulti-usermultiple-inputmultiple-outputorthogonalfrequencydivisionmultiplexing(MIMO-OFDM)systemswithchannelstateinformation(CSI)ontransmitterandreceiverispressed.Multi-userpowerallocationcanbedecoupledintosingleuserpowerallocationthroughoutnullspacemappingofmulti-userchannelandpowerallocationcanbeperformedthroughoutspatial-spectralwater-fillingforperuser.Todealwithmoreusersinsystemandfadingcorrelation,schedulingisperformedtomaintainthegainofpowerallocation.Theproposedschemecansubstantiallyimprovesystem'sspectralefficiencywithlowomplexity.Simulationresultsvalidatetheaccuracyoftheoreticanalyses.
简介:Analgorithmofhighlymaneuveringtargettrackingisproposedtosolvetheproblemoflargetrackingerrorcausedbystrongmaneuver.Inthisalgorithm,anewestimator,namedasmulti-parameterfusionSinger(MF-Singer)modelisderivedbasedontheSingermodelandthefuzzyreasoningmethodbyusingradialaccelerationandvelocityofthetarget,andappliedtotheproblemofmaneuveringtargettrackinginstrongmaneuveringenvironmentandoperatingenvironment.ThetrackingperformanceoftheMF-Singermodelisevaluatedandcomparedwithothermanueveringtrackingmodels.ItisshownthattheMF-Singermodeloutperformsthesealgorithmsinseveralexamples.
简介:Inthispaper,weproposeadynamicmulti-descriptorfusion(DMDF)approachtoimprovingtheretrievalaccuracyof3-dimensional(3D)modelretrievalsystems.First,anindependentretrievallistisgeneratedbyusingeachindividualdescriptor.Second,weproposeanautomaticrelevant/irrelevantmodelsselection(ARMS)approachtoselectingtherelevantandirrelevant3Dmodelsautomaticallywithoutanyuserinteraction.Aweighteddistance,inwhichtheweightassociatedwitheachindividualdescriptorislearntbyusingtheselectedrelevantandirrelevantmodels,isusedtomeasurethesimilaritybetweentwo3Dmodels.Furthermore,adescriptor-dependentadaptivequerypointmovement(AQPM)approachisemployedtoupdateeveryfeaturevector.Thissetofnewfeaturevectorsisusedtoindex3Dmodelsinthenextsearchprocess.Four3DmodeldatabasesareusedtocomparetheretrievalaccuracyofourproposedDMDFapproachwithseveraldescriptorsaswellassomewell-knowninformationfusionmethods.ExperimentalresultshaveshownthatourproposedDMDFapproachprovidesapromisingretrievalresultandalwaysyieldsthebestretrievalaccuracy.
简介:Amemeticalgorithm(MA)foramulti-moderesourceconstrainedprojectschedulingproblem(MRCPSP)isproposed.WeuseanewfitnessfunctionandtwoveryeffectivelocalsearchproceduresintheproposedMA.Thefitnessfunctionmakesuseofamechanismcalled'strategicoscillation'tomakethesearchprocesshaveahigherprobabilitytovisitsolutionsarounda'feasibleboundary'.Oneofthelocalsearchproceduresaimsatimprovingthelowerboundofprojectmakespantobelessthanaknownupperbound,andanotheraimsatimprovingasolutionofanMRCPSPinstanceacceptinginfeasiblesolutionsbasedonthenewfitnessfunctioninthesearchprocess.AdetailedcomputationalexperimentissetupusinginstancesfromtheprobleminstancelibraryPSPLIB.ComputationalresultsshowthattheproposedMAisverycompetitivewiththestate-of-the-artalgorithms.TheMAobtainsimprovedsolutionsforoneinstanceofsetJ30.
简介:Thewide-swathmethodbasedonmulti-receiverisanovelandhighlyaccuratewide-swathmethod,whichrequiresaverypreciseviewangle.Theestimatedanglehaserrorbecauseoftheatmosphererefraction,angleerrorofviewandtargetheight.Amethodisproposedinthispapertoestimatetheangleerrorfromthereturnsignal.Themethodmakesuseoftherelationshipbetweentheviewangleerrorandthesignalcorrelationofthesubswathstoestimatetheangleerror.Theprecisionofthismethodisanalyzedbythelawofgreatnumberanditturnsouttobeindirectproportiontotherootsquarenumberofaveraging.Thesimulationresultisgivenandtheangleprecisionis0.025°.
简介:AMinimizingIntermediateMulticastRoutingprotocol(MIMR)isproposedfordynamicmulti-hopadhocnetworks.InMIMR,multicastsessionsarecreatedandreleasedonlybysourcenodes.Ineachmulticastsessionprocess,thesourcenodekeepsalistofintermediatenodesanddestinations,whichisencapsulatedintothepacketheaderwhenthesourcenodesendsamulticastpacket.Nodesreceivingmulticastpacketsdecidetoacceptorforwardthepacketaccordingtothelist.Dependingontopologymatrixmaintainedbyunicastrouting,theshortestvirtualhierarchyroutingtreeiscon-structedbyimprovedDijkstraalgorithm.MIMRcanachievetheminimumnumberofintermediatenodes,whicharecomputedthroughthetree.Nocontrolpacketistransmittedintheprocessofmul-ticastsession.Loadofthenetworkislargelydecreased.ExperimentalresultshowsthatMIMRisflexibleandrobustfordynamicadhocnetworks.
简介:Uncertainandhesitantinformation,widelyexistinginthereal-worldqualitativedecisionmakingproblems,bringsgreatchallengestodecisionmakers.Hesitantfuzzylinguistictermsets(HFLTSs),aneffectivelinguisticcomputationaltoolinmodelingandelicitingsuchinformation,havehencearousedmanyscholars’interestsandsomeextensionshavebeenintroducedrecently.However,thesemethodsarebasedonthediscretelinguistictermframeworkwiththelimitedexpressiondomain,whichactuallydepictqualitativeinformationusingseveralsinglevalues.Therefore,itishardtoensuretheintegrityofthesemanticsrepresentationandtheaccuracyofthecomputationresults.Todealwiththisproblem,asemanticsbasisframeworkcalledcompletelinguistictermset(CLTS)isdesigned,whichadoptsaseparationstructureoflinguisticscaleandexpressiondomain,enrichingsemanticsrepresentationofdecisionmakers.Onthisbasistheconceptoffuzzyintervallinguisticsets(FILSs)isputforwardthatemploystheintervallinguistictermwithprobabilitytoincreasetheflexibilityofelicitingandrepresentinguncertainandhesitantqualitativeinformation.Forpracticalapplications,afuzzyintervallinguistictechniquefororderpreferencebysimilaritytoidealsolution(FILTOPSIS)methodisdevelopedtodealwithmulti-attributegroupdecisionmaking(MAGDM)problems.Throughthecasesofmovieandenterpriseresourceplanning(ERP)systemselection,theeffectivenessandvalidityoftheproposedmethodareillustrated.
简介:Theparallelinterferencecancellationformulti-carrierDS-CDMA(whichistermedFDC-PIC)isproposedbyintegratingfrequencydiversitycombination.ThesimulationsaremadeoverFDC-PICwithrespecttodifferentdecisionways-hard,softandlineardecisions,respectively,andweconcludethatFDC-PICacquiressuperiorperformanceimprovementovercorrelationreceptionofmulti-carrierDSCDMA.Withanincreaseininterferencecancellationstages,thesystemperformanceisimprovedfurther.Theinitial2stagesbringaboutthemostdominantperformanceimprovement,butuptothe3rdstagethesystemperformanceisimprovedlittle.ItisalsoshownbythesimulationresultsthatFDC-PICwithsoftdecisionwouldexhibitthebestperformancewithahighimplementationcomplexity,whileFDC-PICwithlineardecisionacquiresperformancecomparabletothatofFDC-PICwithsoftdecisionwithareduced-complexityifthenumberoftheinterferencecancellationstagesisthesame,whichindicatesthatFDC-PICwithlineardecisionhasoptimalperformance/complexitytradeoffandthereforewillbesuitableforpracticalapplicationinfuture.
简介:Basedontheelectromagneticfieldtheory,theopticalsignaltransmissioncharacteristicsininput/outputwaveguides,slabwaveguidesandarrayedwaveguidesofthearrayedwaveguidegrating(AWG)multi/demultiplexerareanalyzed.TherelationshipbetweenthephysicalparameterssuchasgeometrysizesandrelativerefractiveindexinAWGmulti/demultiplexerandtheopticalsignaltransmissioncharacteristicsarediscussed.ThistheoreticalstudycanbeusedforoptimizingthedesignandimprovingtheperformanceoftheAWGmulti/demultiplexer.
简介:Inthispaper,anAntColonySystem(AC)basedheuristicalgorithmispresentedtofindthemulti-constraineddynamicQualityofService(QoS)multicastrouting.WealsoexplorethescalabilityoftheACalgorithmandmulticasttreebyusing"Pull"modeinsteadof"Push"mode,andtheimprovementonthetimecomplexityofACalgorithmbyusinganewdatastructure,I.e.,apointerarrayinsteadoftheprevious"matrix"structure.Ourextensivetestsshowthatthepresentedalgorithmcanfindtheglobaloptimumorsuboptimum,andhasagoodscalabilitywithdynamicadaptationtothechangeofmulticastgroup,andgivesbetterperformanceintermsofthetotalcostthanothertwoalgorithms.
简介:Gettingalongwiththeimprovementofgreencommunications,theenergyefficiency(EE)ofwirelessnetworkbecomesmoreandmoreimportant.However,inmulti-relay-assistedsystems,therelatedworkobviouslydependsontheend-to-endperformance,whereasEEofrelayshasnotattractedenoughattention.Theauthorsproposeanorthogonalfrequencydivisionmultiplexing(OFDM)multi-relaysystembasedonamplifyandforward(AF)mode.TakingincorporatingEEandremainingenergyasfactor,decisioncriteriaofattendingcooperationisdesigned.TheEEbasedasynchronouspoweriterationmethodispresented,andtheexistenceandconvergenceofnashequilibrium(NE)isproven.Furthermore,ajointalgorithminsubcarrierpairing,relayselectionandpowerallocationisgiven.Geneticalgorithm(GA)anditerationmethodareintegratedtoimprovetheconvergencespeedadditionally.SimulationdemonstratestheobviousimprovementofEE,decreaseofpowerconsumptionandincreaseoflifetimeinrelaysofthisalgorithmwiththeconstraintofminimumdatatransmissionrate.
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:Thispaperproposesanantennadesignconcepttoachieveamulti-reconfigurableband-notchantennabyusingasetofmicroswitches.Theproposedideawasprovedbythedesignofthecoplanarwaveguide(CPW)-fedslotantenna.Thesampledesigngivesawidebandantennatheimpedancebandwidthofwhichcoversthefrequencyrangedfrom1.9GHzto6.55GHz.Theantennacouldbeconfiguredtoworkeitherinsingle-bandmodeorinoneofthedefineddual-bandmodes.
简介:Anovelhorizontalpush-pullmulti-substrateepitaxyboatwiththreeseparatecellsisintroducedinthisarticle,withmulti-substrateLPEprocessingisfeasibleinhorizontalLPEfurnace.TheprocessesofLPEAlxGa1-xAs/GaAssolarcellsarestudiedandtheefficiencyofthesolarcellsachieved19.8%(AM0,25℃,120mW/cm^2).
简介:mc2llvmisaprocess-levelARM-to-x86binarytranslatordevelopedinourlabinthepastseveralyears.Currently,itisabletoemulatesinglethreadedprograms.Weextendmc2llvmtoemulatemulti-threadedprograms.Ourmaintaskistoreconstructitsarchitectureformulti-threadedprograms.Registermapping,codecachemanagement,andaddressmappinginmc2llvmhaveallbeenmodified.Inaddition,tofurtherspeeduptheemulation,wecollecthotpaths,aggressivelyoptimizeandgeneratecodeforthematruntime.Additionalthreadsareusedtoalleviatetheoverhead.Thus,whenthesamehotpathiswalkedthroughagain,thecorrespondingoptimizednativecodewillbeexecutedinstead.Inourexperiments,oursystemis8.8XfasterthanQEMU(quickemulator)onaveragewhenemulatingthespecifiedbenchmarkswith8guestthreads.
简介:Afuzzyparticleswarmoptimization(PSO)onthebasisofelitearchivingisproposedforsolvingmulti-objectiveoptimizationproblems.First,anewperturbationoperatorisdesigned,andtheconceptsoffuzzyglobalbestandfuzzypersonalbestaregivenonbasisofthenewoperator.Afterthat,particleupdatingequationsarerevisedonthebasisofthetwonewconceptstodiscouragetheprematureconvergenceandenlargethepotentialsearchspace;second,theelitearchivingtechniqueisusedduringtheprocessofevolution,namely,theeliteparticlesareintroducedintotheswarm,whereastheinferiorparticlesaredeleted.Therefore,thequalityoftheswarmisensured.Finally,theconvergenceofthisswarmisproved.TheexperimentalresultsshowthatthenondominatedsolutionsfoundbytheproposedalgorithmareuniformlydistributedandwidelyspreadalongtheParetofront.
简介:磁电机眼(瞬间)与微波magnetostatic波浪(MSW)指导光波浪联合同时由信号能导致的多重收音机频率(RF)激动RF信号的multifrequency衍射效果然后并行处理能被衍射效率(Des)是的特征使用认识到近似在里面到RF信号紧张和衍射角度的直接比例与在线性瞬间相互作用区域以内的相应RF信号的频率有关。在这份报纸,学习了是在一阶的瞬间相互作用近似的multifrequency瞬间布拉格衍射,并且获得是为原则衍射效率(PDE)的近似分析表示。另外,提出基于单个频率的衍射是RF信号的相对紧张的一个平行成像方法。由计算和分析,相对错误是为在内的三个RF信号的盒子的不超过0.3dB60MHz的频率空间,这被显示出。