学科分类
/ 19
376 个结果
  • 简介:D-η-珍视向量的功能的合适的prequasi-invexity被描绘借助于(弱)将近集合的凸状和密度。在更弱的假设下面,某等价物为D-调节η-合适的prequasi-invexity被导出。

  • 标签: 凸集 半连续性 弱函数 等效条件
  • 简介:Study on IMF Emission in 30 MeV/u 40Ar Induced ReattionsStudyonIMFEmissionin30MeV/u40ArInducedReattions¥ZhuYongtai;XuHus...

  • 标签:
  • 简介:ThepropertiesofPbn(n=2―30)clustersincludingbindingenergies,seconddifferencesinenergy,andHOMO-LUMOgaps,especiallyfragmentationenergiesandionizationpotentials,havebeenstudiedbyabinitiocalculation.ThemainfragmentationproductsofPbn+areshowntobePb+Pbn-1+forn≤14andtwosmallclusterfragmentsforlargeroneswithn>14.ThePb13+appearsfrequentlyastheproductsinthefragmentationsoflargeclusters.Also,thecalculatedionizationpotentialsoftheclustersareconsistentwiththeexperimentdata.

  • 标签: 电离势 碎裂 集群计算 HOMO LUMO 从头计算
  • 简介:Veryrecently,theBelleandBESIIIexperimentsobservedanewcharmonium-likestateX(3823),whichisagoodcandidatefortheD-wavecharmonium(13D2).BecausetheX(3823)isjustneartheDˉDthreshold,thedecayX(3823)!J=+??canbeagoldenchanneltotestthesignificanceofcoupled-channeleffects.Inthiswork[1],thisdecayisconsideredincludingboththehidden-charmdipionandtheusualquantumchromodynamicsmultipoleexpansion(QCDME)contributions.

  • 标签: IDENTIFY COUPLED-CHANNEL EFFECTS
  • 简介:或者方向性含蓄(ADI)计划通常在3D深度移植被使用。它切开3D沿着英文报纸之单行标题和嵌入的方向的方形根的操作员或者。在这糊,基于数据线,四方法的切开计划和他们的切开的错误为的理想有限差别(FD)方法和混合方法被调查。四方法的切开的计划的wavefieldextrapolation在一根数据线上被完成并且无条件地是稳定的。切开错误的数字分析证明双向FD迁居有可见数字各向异性的错误,和移植更不有的那四方法的FD比双向FD移植切开错误。为混合方法,在双向计划和四方法的计划之间的数字各向异性的错误的差别在更低的侧面的速度变化的情况中是小的。在这篇论文介绍的计划能在栈以后的3D或prestack深度移植被使用。3D深度移植的二数字计算被完成。一个人是四方法的FDand混合3D为推动回答的栈以后的深度移植,哪个各向异性的错误能在经常、可变的速度变化的情况中有效地被消除的表演。Theother是为有切开计划的two-wayhybrid的SEG/EAEG基准模型的3D射击侧面prestack深度迁居,它介绍好成像结果。基于射击数字传递接口(MPI)计划的消息被采用。

  • 标签: 3D深度偏移 多路分裂 数据线 波场计算 有限差分 数学分析
  • 简介:

  • 标签:
  • 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:Thisletterobtainsatyphoon-likevortexsolutionbysolvingtheBragg-Hawthorneequation.ThesolutiondescribesspiralpathsoffluidmaterialelementontheBernoullisurface,whereassomenewexactsolutionsareobtainedwhichareboundedinthewholeregion.Thefirstoneisacontinuedumbrellavortexsolution,whichisatyphoon-likevortex.Thesecondoneisamulti-planarsolution,whichisperiodicinz-coordinate.Withineachlayer,thereisanumbrellavortexsolutionsimilartothefirstone.Theabove...

  • 标签:
  • 简介:InthispaperwestudythecomputationalperformanceofvariantsofanalgebraicadditiveSchwarzpreconditionerfortheSchurcomplementforthesolutionoflargesparselinearsystems.Inearlierworks,thelocalSchurcomplementswerecomputedexactlyusingasparsedirectsolver.Therobustnessofthepreconditionercomesatthepriceofthismemoryandtimeintensivecomputationthatisthemainbottleneckoftheapproachfortacklinghugeproblems.InthisworkweinvestigatetheuseofsparseapproximationofthedenselocalSchurcomplements.TheseapproximationsarecomputedusingapartialincompleteLUfactorization.Suchanumericalcalculationisthecoreofthemulti-levelincompletefactorizationsuchastheoneimplementedinpARMS.Thenumericalandcomputingperformanceofthenewnumericalschemeisillustratedonasetoflarge3Dconvection-diffusionproblems;preliminaryexperimentsonlinearsystemsarisingfromstructuralmechanicsarealsoreported.

  • 标签: 稀疏逼近 三维 代数 求解器 舒尔补 SCHUR补
  • 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:Inthispaper,least-squaxesmirrorsymmetricsolutionformatrixequations(AX=B,XC=D)anditsoptimalapproximationisconsidered.Withspecialexpressionofmirrorsymmetricmatrices,ageneralrepresentationofsolutionfortheleast-squaresproblemisobtained.Inaddition,theoptimalapproximatesolutionandsomealgorithmstoobtaintheoptimalapproximationareprovided.

  • 标签: 反射对称矩阵 最佳逼近 矩阵方程 算法
  • 简介:Regardforthefuzzinessandtherandomnessinsomeacousticfields,amethodforthenumericalanalysisofthe2DacousticfieldwithFuzzy-Randomparameterswasproposedbasedontheequivalentconversionofinformationentropy.Intheproposedmethod,afuzzyrandomacousticfieldwastreatedasapurefuzzyacousticfieldorapurerandomacousticfieldbytransformingallthevariablesintofuzzyvariablesorrandomvariables.Perturbationfiniteelementmethodsforanalyzingthetwo-dimensionalacousticfuzzyandrandomfieldarededuced.Thesoundpressureresponseofa2Dacoustictubeandthe2Dacousticcavityofacarwithfuzzy-randomparameterswereanalyzedbytheproposedmethodandtheMonteCarlomethod,theresultsshowthattheproposedmethodcanbewellappliedtothenumericalanalysisofthe2Dacousticfieldwithfuzzy-randomparameters,andhasgoodprospectofengineeringapplication.

  • 标签: 数值分析方法 随机参数 模糊性 声场 二维 蒙特卡罗方法
  • 简介:Laminatedcompositematerialsarewidelyimplementedinseveralengineeringconstructions.Foritsrelativelightweight,thesematerialsaresuitableforaerospace,military,marine,andautomotivestructuralapplications.Toobtainsafeandeconomicalstructures,themodellinganalysisaccuracyishighlyrelevant.Sincemeshlessmethodsintherecentyearsachievedaremarkableprogressincomputationalmechanics,thepresentworkusesoneofthemostflexibleandstableinterpolationmeshlesstechniqueavailableintheliterature—theRadialPointInterpolationMethod(RPIM).Here,a2Dapproachisconsideredtonumericallyanalysecompositelaminatedbeams.Boththemeshlessformulationandtheequilibriumequationsrulingthestudiedphysicalphenomenonarepresentedwithdetail.Severalbenchmarkbeamexamplesarestudiedandtheresultsarecomparedwithexactsolutionsavailableintheliteratureandtheresultsobtainedfromacommercialfiniteelementsoftware.Theresultsshowtheefficiencyandaccuracyoftheproposednumerictechnique.

  • 标签: RADIAL POINT interpolators RPIM LAMINATED BEAM
  • 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