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120 个结果
  • 简介:Thecomplexbandstructuresofa1Danisotropicgraphenephotoniccrystalareinvestigated,andthedispersionrelationsareconfirmedusingthetransfermatrixmethodandsimulationofcommercialsoftware.Itisfoundthattheresultofusingeffectivemediumtheorycanfitthederiveddispersioncurvesinthelowwavevector.Transmission,absorption,andreflectionatobliqueincidentanglesarestudiedforthestructure,respectively.Omni-gapsexistforanglesashighas80°fortwopolarizations.Physicalmechanismsofthetunabledispersionandtransmissionareexplainedbythepermittivityofgrapheneandtheeffectivepermittivityofthemultilayerstructure.

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  • 简介:<正>AneffectiverelativisticcontinuummassiveProcaLagrangianactionisusedtoaccountfortheLorentzvectorcondensationeffectsontheequationofstateofthestronglyinteractingfermionssystem.TheinteriorquantumfluctuationeffectsareincorporatedasanexternalfieldapproximationindirectlythroughafictivegeneralizedThomsonProblemcountertermbackground.Thegeneralanalyticalformulasforthed-dimensionalthermodynamicsaregivenneartheunitarylimitregion,Inthenon-relativisticlimitford=3,theuniversaldimensionlesscoefficientε=4/9andenergygap△/ε_f=5/18arereasonablyconsistentwiththeexistingtheoreticalandexperimentalresults.Intheunitarylimitford=2andT=0,theuniversalcoefficientcanevenapproachtheextremeoccasionξ=0correspondingtotheinfiniteeffectivefermionmassm~*=∞,whichcanbemappedtothestronglycoupledtwo-dimensionalelectronsandisquitesimilartothethree-dimensionalBose-Einsteincondensationofidealbosongas.Instead,ford=1,theuniversalcoefficientξisnegative,implyingthenon-existenceofphasetransitionfromsuperfluiditytonormalstate.ThesolutionsmanifestthequantumIsinguniversalclasscharacteristicofthestronglycoupledunitaryfermionsgas.

  • 标签: UNITARY FERMIONS THERMODYNAMICS BEC-BCS CROSSOVER STATISTICAL
  • 简介:IGUANA(InteractiveGraphicsforUserANAlysis)isaC++toolkitfordevelopinggraphicaluserinterfacesandhighperformance2-Dand3-Dgraphicsapplications,suchasdatabrowsersanddetectorandeventvisualisationprograms.TheIGUANAstrategyistousefreelyavailablesoftware(e.g.Qt,SoQt,OpenInventor,OpenGL,HEPVis)andpackageandextendittoprovideageneral-purposeandexperiment-independenttoolkit.WedescribetheevaluationandchoicesofpubliclyavailableGUI/graphicssoftwareandtheadditionalfunctionalitycurrentlyprovidedbyIGUANA.WedemonstratetheuseofIGUANAwithseveralapplicationsbuiltforCMSandD0.

  • 标签: 计算机图形学 交互图形 CMS DO CMS
  • 简介:Inthispaper,wepresentanovelSupportVectorMachineactivelearningalgorithmforeffective3Dmodelretrievalusingtheconceptofrelevancefeedback.Theproposedmethodlearnsfromthemostinformativeobjectswhicharemarkedbytheuser,andthencreatesaboundaryseparatingtherelevantmodelsfromirrelevantones.Whatitneedsisonlyasmallnumberof3Dmodelslabelledbytheuser.Itcangrasptheuser'ssemanticknowledgerapidlyandaccurately.Experimentalresultsshowedthattheproposedalgorithmsignificantlyimprovestheretrievaleffectiveness.Comparedwithfourstate-of-the-artqueryrefinementschemesfor3Dmodelretrieval,itprovidessuperiorretrievalperformanceafternomorethantworoundsofrelevance

  • 标签: 多媒体技术 计算机软件 3D技术 检索方法
  • 简介:在这研究,为波浪精力变换与固定指南翼推进一台推动汽轮机的表演的改进以便完成,表演上的指南翼形状的效果被实验调查。调查被模型在稳定的流动状况下面测试执行。作为结果,因为转矩的增加,有3D指南翼的汽轮机的效率比有2D指南翼的汽轮机的稍微优异,这被发现指南翼,尽管越过为3D案例的汽轮机的压力落下为2D案例比那稍微高。关键词液体机械-推动汽轮机-指南翼-波浪精力变换CLC数字TK735

  • 标签: 流体机械 冲量涡轮 风向导向标 波能量转化率 水轮机
  • 简介:Atopologymethodispresentedinthispapertorevealflowtructureoccurringinsieturbomachinery,inwhichnearwallflowstructureisrevealedbyusingwalllimitingstreamilinesandspaceflowfeatureisrevealedbyusingspacestreamilinesandcross-sectionstreamlines,Asanexample,acomputationalthree-dimensionalviscousflowfieldinsideatransonicturbinecascadeisstudied.Throughtheanalysis,theformandevolutionofvortexsystemandthewholeprocessofseparationoccurringwithinthiscascadearerevealed.Theapplicationoftopologymethodforanalyzeflowstructureinsideturbomachinmeryisveryimportantforunderstandingflowfeaturesandmechanismofflowlossevenforimprovingthedesignofturbomachineryandincreasingitsefficiency.

  • 标签: 超声速透平机 粘滞流体 拓扑结构
  • 简介:Wepropose,inthispaper,touseseveralmultivariateanalysismethodeandanewkindofvariablestoseparatebetweenfourclassesofeventsproducedatLEP2:theeventswith2jets,3jets,4jetsandthosehavingamoreabundantjettopology(njets,n>4)Neuralnetworkhaveproventhemselvestobemoreefficientclassifierthantheothertechniques.Theefficienciesandpuritiesachievedwiththeoptimizedneuralnetworkareinaverage1to7%higherthanthoseobtaindwiththeothermethods.

  • 标签: e^+e^-碰撞实验 神经网络 喷射注数
  • 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。

  • 标签: 跨音速压气机 转子 叶片参数 空气动力学设计 优化
  • 简介:在多孔的媒介和液体之间的热和集体转移是一个复杂联合过程,它广泛地在设计应用的各种各样的地里被使用,特别为在油和煤气的抽取的自然、人工的破裂。在这研究,一个新方法被建议在破裂处理流动和稳定的流动的热转移问题。在破裂的液体流动用象Mohais的一样的方法被描述,与多孔的墙,和不安方法把破裂看作了一条隧道的人,被用来解决数学模型。不同于以前的研究,shear跳Ochoa-Tapia和Whitaker建议的边界状况在在液体和多孔的媒介之间的接口被使用。主要方法是不安分析和申请砍跳边界条件。渗透的影响,隧道宽度,砍跳在隧道的流动和热转移上的度和有效动态粘性被分析分析答案学习。在有典型参数和热转移的敏感的变化的隧道的轴的速度的分发被获得。

  • 标签: 多孔介质 人工裂缝 流动传热 二维流动 模拟分析 通道宽度
  • 简介:Theshiftinthepercolationthresholdofcompressedcompositeswasstudiedbya3Dcontinuumpercolationmodel.AMonteCarlo(MC)methodwasemployedinthesimulations.Thepercolationthresholdwasfoundtorisewiththecompressionstrain,whichcapturesthebasictrendincompression-inducedconductivityvariationfromtheexperiments.Bothfiberbendingandtextureformationcontributetothepercolationthreshold.Theresultssuggestthatfillerswithahighaspectratioaremoredesirableforsensorandelectricalswitchapplications.

  • 标签: 蒙特卡洛模拟 压缩应变 复合材料 渗滤阈值 三维 漂移
  • 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.

  • 标签: 燃烧室 气-粒子流 数字模拟
  • 简介:Thenonstaggeredgridsareadoptedinthispaperforsolvingthegoverningequationsofflowsinthecurvilinearcoordinatesystems.Thepresentpaperdemonstratesthebasicreasonandcorrespondingeliminatingmethodforthepressureoscillation,anddeducesthecorrectedexpressionsforthecurvilinearvelocitycomponentsinwhichandadditionaltermrepresentingthedifferencebetweenthe1-δand2-δdifferencevaluesforthepressuregradientappears.Thusifanoscillatorypressurefiledwerearisen,themagnitudeofthistermwouldbelargeandwouldacttoremovetheoscillation;whereasfornonoscillatoryfieldthemagnitudeofthistermremainssmall.Asexaminationforthenumericalmethod3-Dturbulentflowinasquareductwith90°bendand3-Dturbulentmixinglowinalobed-mixerwerecalculatiedrespectively.Thenumericalresultsaresatisfactory.

  • 标签: 涡流 压强振荡 曲线坐标系
  • 简介:Basedonconsolidationequationsproposedforunsaturatedsoil,ananalyticalsolutionfor1Dconsolidationofanunsaturatedsingle-layersoilwithnonhomogeneousmixedboundaryconditionisdeveloped.Themixedboundaryconditioncanbeusedforspecialapplications,suchastestsoccurinlaboratory.Theanalyticalsolutionisobtainedbyassumingallmaterialparametersremainconstantduringconsolidation.Inthederivationoftheanalyticalsolution,thenonhomogeneousboundaryconditionisfirsttransformedintoahomogeneousboundarycondition.Then,theeigenfunctionandeigenvaluearederivedaccordingtotheconsolidationequationsandthenewboundarycondition.Finally,usingthemethodofundeterminedcoefficientsandtheorthogonalrelationoftheeigenfunction,theanalyticalsolutionforthenewboundaryconditionisobtained.Thepresentmethodisapplicabletovarioustypesofboundaryconditions.Severalnumericalexamplesareprovidedtoinvestigatetheconsolidationbehaviorofanunsaturatedsingle-layersoilwithmixedboundarycondition.

  • 标签: 英文摘要 编辑工作 优秀论文 医学期刊