简介:Inthispaper,wepresentanovelSupportVectorMachineactivelearningalgorithmforeffective3Dmodelretrievalusingtheconceptofrelevancefeedback.Theproposedmethodlearnsfromthemostinformativeobjectswhicharemarkedbytheuser,andthencreatesaboundaryseparatingtherelevantmodelsfromirrelevantones.Whatitneedsisonlyasmallnumberof3Dmodelslabelledbytheuser.Itcangrasptheuser'ssemanticknowledgerapidlyandaccurately.Experimentalresultsshowedthattheproposedalgorithmsignificantlyimprovestheretrievaleffectiveness.Comparedwithfourstate-of-the-artqueryrefinementschemesfor3Dmodelretrieval,itprovidessuperiorretrievalperformanceafternomorethantworoundsofrelevance
简介:Atopologymethodispresentedinthispapertorevealflowtructureoccurringinsieturbomachinery,inwhichnearwallflowstructureisrevealedbyusingwalllimitingstreamilinesandspaceflowfeatureisrevealedbyusingspacestreamilinesandcross-sectionstreamlines,Asanexample,acomputationalthree-dimensionalviscousflowfieldinsideatransonicturbinecascadeisstudied.Throughtheanalysis,theformandevolutionofvortexsystemandthewholeprocessofseparationoccurringwithinthiscascadearerevealed.Theapplicationoftopologymethodforanalyzeflowstructureinsideturbomachinmeryisveryimportantforunderstandingflowfeaturesandmechanismofflowlossevenforimprovingthedesignofturbomachineryandincreasingitsefficiency.
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简介:现在的纸为与快速的3D片和格子生成器(RAPID3DGRID)相结合的turbomachinery的空气动力学的设计描述优化方法论,一个N.S解答者,一个片parameterization方法(BPM),一个基于坡度的analyseparameterization方法(GPAM),有激增的一个反应表面方法(RSM)算法和一个简单坡度方法。由片parameterization方法的使用,一个接近音速的压缩机转子能被一套多项式表示,然后它使我们能转变表示坐标的片数据到表示参数然后减少参数的数字。与改变任何一个参数,我们能获得几组样品。这里,仅仅十个参数被认为寻找一个优化压缩机转子。由于优化,断热的效率被1.73%增加。
简介:Theshiftinthepercolationthresholdofcompressedcompositeswasstudiedbya3Dcontinuumpercolationmodel.AMonteCarlo(MC)methodwasemployedinthesimulations.Thepercolationthresholdwasfoundtorisewiththecompressionstrain,whichcapturesthebasictrendincompression-inducedconductivityvariationfromtheexperiments.Bothfiberbendingandtextureformationcontributetothepercolationthreshold.Theresultssuggestthatfillerswithahighaspectratioaremoredesirableforsensorandelectricalswitchapplications.
简介:The3-Dturbulentgas-particleflowsinaninnovativecombustorcalled“Spouting-CycloneCombustor”aresimulatedusingak-ε-Aptwo-phaseturbulencemodel.Theresultsshowthat:(1)THepredictedresultsinthespoutingzoneareingoodagreementwiththeexperimentalones;thepredictedgasflowfieldinthecyclonezoneisneartothatmeasured;(2)Inthespoutingzone,thereisalarge-sizegasparticlerecirculationzoneandasmall-sizeoneinthex-rplane,whichisfavorabletoburningcoarsecoalparticles;Inalmosteveryr-θplane,thereareseveralgas-particlevortices,whichisbeneficialtothemixing,heatandmasstransferbetweentwophases,thus,tothetwo-phasecombustion.(3)Thereisremarkablevelocityslipbetweengasandparticlephases;(4)Inthecyclonezone,predictionsshowtheoccurrenceofrecirculatingsecondaryflowsandcounterswirlingflowsinsomecrosssections,suchphenomenaaredifficulttobeobservedbyexperimentalmethods.
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简介:Thenonstaggeredgridsareadoptedinthispaperforsolvingthegoverningequationsofflowsinthecurvilinearcoordinatesystems.Thepresentpaperdemonstratesthebasicreasonandcorrespondingeliminatingmethodforthepressureoscillation,anddeducesthecorrectedexpressionsforthecurvilinearvelocitycomponentsinwhichandadditionaltermrepresentingthedifferencebetweenthe1-δand2-δdifferencevaluesforthepressuregradientappears.Thusifanoscillatorypressurefiledwerearisen,themagnitudeofthistermwouldbelargeandwouldacttoremovetheoscillation;whereasfornonoscillatoryfieldthemagnitudeofthistermremainssmall.Asexaminationforthenumericalmethod3-Dturbulentflowinasquareductwith90°bendand3-Dturbulentmixinglowinalobed-mixerwerecalculatiedrespectively.Thenumericalresultsaresatisfactory.
简介:Thispaperpresentsanexperimentalstudyofthethree-dimensionalturbulentflowfieldsinalowspeedannularcascadeofhighturningangleturbineblades.Detailedmeasurementswereperformedonthebladesurfacesandmid-streamsurfaceinthepassageandatthreeaxialplanesdownstreamofthecascadebyusingwallstaticpressuretaps,afive-holeprobeandahot-wireanemometer,Thetestdataincludestaticpressuredistributiononbladesurfaces,totalpressurelosscofeeicient,meanflowvelocitycomponents.radialflowangle,turbulenceintensityandReynoldsshearstress.Analysesofthethree-dimensionalcascadeflowcharacteristicsweremadeonthenosetlocationofhighlossvortices.thevariationofpressuregradientinsidethecascadepassageandthepropertiesofendwallboundarylayerstotalpressurelossdistributions,secondaryvortexturbulentdissipationandwakedecaydowntreamofthecascade.Theseexperimentalresultsarevaluableforrevealingthedetailsofthecomplexvortexflowstructureinmodernhighlyloadedaxialturbomachinesandvalidatingthethree-dimensionalflownumericalcomputationcodes.
简介:Inthiswork,anewmethodtodealwiththeunconnectedpixelsinmotioncompensatedtemporalfiltering(MCTF)ispresented,whichisdesignedtoimprovetheperformanceof3Dliftedwaveletcoding.Furthermore,multipledescriptionscalablecoding(MDSC)isinvestigated,andnovelMDSCschemesbasedon3Dwaveletcodingareproposed,usingtheliftingimplementationoftemporalfiltering.TheproposedMDSCschemescanavoidthemismatchprobleminmultipledescriptionvideocoding,andhavehighscalabilityandrobustnessofvideotransmission.Experimentalresultsshowedthattheproposedschemesarefeasibleandadequatelyeffective.