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24 个结果
  • 简介:Inthispaper,weconsiderthenonsymmetricalhalf-planeprediction.Apredictiontheoreticproofofthefundamentalformulaaboutonesteppredictionerrorisgiven.AWold-typedecompositionanditsspectralrepresentationtheoremareproved.Spectralextractionproblemsofthehalf-planeinnova-tionsanditssingularcomponentsareinvestigated.

  • 标签: SINGULAR proof REGULARITY whenever PRED ANSWER
  • 简介:Let{N(t),t≥0}bethenonhomogeneousPoissonprocesswithcumulativeintensityparameterΛ(t),{δt,t≥0}theageprocess,and{yi,t≥0)theresiduallifetimeprocess.Inthepresentpapertheexpressionsofn-dimensionalsurvivaldistributionfunctionsoftheprocesses{δi}and{yi},andtheirLebesguedecompositionsarederived.

  • 标签: 不均匀布松过程 剩余时间 勒贝格分解 分布函数
  • 简介:Thelifetimeofanartificialsatellitemovinginthecircularorbitundertheactionofnonuniformrotatingatmosphericdragisstudiedfromanenergypointofviewinthispaper.Theangularvelocityofatmosphericrotationdecreaseswithheightaccordingtohydrodynamics.Theatmosphericdensitydecreaseswithheightaccordingtotheexponentialformula.Theexpressionforthelifetimeofasatelliteintheinstantaneouscircularorbitintheabove-mentionedrotatingatmosphericmodelisderived,andthenumericalestimationforthelifetimeofaconcretesatellitehasbeenmade.Theresultshowsclearlythatthesatellitelifetimecalculatedbythispaperisshorterthanthatcalculatedbytheuniformrotatingatmosphericmodel.

  • 标签: NONUNIFORM ROTATING ATMOSPHERIC drag satellite LIFETIME
  • 简介:Emission Time of Light Particles and Lifetime of Hot Nuclei Following Binary FissionEmissionTimeofLightParticlesandLifetimeof...

  • 标签: TIME
  • 简介:Inthispaper,wehavediscussedarandomcensoringtestwithincompleteinformation,andprovedthatthemaximumlikelihoodestimator(MLE)oftheparameterbasedontherandomlycensoreddatawithincompleteinformationinthecaseoftheexponentialdistributionhasthestrongconsistency.

  • 标签: 一致性 指数寿命分布 随机检验模型 极大似然估计量 MLE
  • 简介:Inthispaper,thetheoryofQuasi-steadyisappliedtothecalculationsofturbochargersmatchingtothedieselenginesandperformanceprediction.Theengineperformancepredictionprogramswritteninlanguaechavebeenusedforcalculationsofvariousturbochargeddieselengines.Ithasbeenconfirmedbythecomparisonswithexperimentaldatathattheresultsofthecalcuationarereasonable,reliableandsatisfiedfortheengineeringapplications.

  • 标签: 透平机 内燃机 性能鉴定 准稳定法
  • 简介:Afugacitymodelwasdevelopedforpredictionofmixedrefrigerantgashydratesformationconditionsbasedonthemoleculecongregationandsolutiontheories.Inthismodel,gashydrateswereregardedasnon-idealsolidsolutioncomposedofwatergroupsandguestmolecules,andtheexpressionsoffugacityofguestmoleculesinhydratephasewasproposedaccordingly.Ithasbeenshownthatthedevelopedmodelcanindicatesuccessfullytheeffectofguest-guestmoleculeinteraction.Theresultsshowedthatthemodelcandescribebetterthecharacteristicsofphaseequilibriumofmixedrefrigerantgashydratesandpredictionsareingoodagreementwithexperimentaldata.

  • 标签: 冷却气体 水化物 形成条件
  • 简介:TheeffectsofF^-ionsinagermanium-lead-telluriteglasssystemonthespectralandpotentiallaserpropertiesoftheYb^3+areinvestigated.Theabsorptionspectra,lifetimes,theemissioncross-sectionsandtheminimumpumpintensitiesoftheglasssystemwithandwithoutF^-ionshavebeenmeasuredandcalculated.TheresultsshowthatthefluorescencelifetimeandtheminimumpumpintensityofYb^3+ionsincreaseevidently,whichindicatesthatgermanium-lead-oxyfluoridetelluriteglassisapromisinglaserhostmatrixforhighpowergeneration.FT-IRspectrawereusedtoanalysetheeffectofF^-ionsonOH^-groupsinthisglasssystem.AnalysisdemonstratesthatadditionoffluorideremovestheOH^-groupsandresultsinimprovementoffluorescencelifetimeofYb^3+.

  • 标签: 荧光寿命 氟离子 锗-铅亚碲酸盐玻璃 掺杂方法 镱离子 激光操作
  • 简介:Amodelwasestablishedtopredictcondensationheattransfercoefficientonhorizontalrectangularfinnedtube.Drop-Offzoneatthetubebottomwasconsideredanddetermined,theknownHonda(andOwen)expressionofretentionanglewasalsomodifiedasaresultofconsideringdrop-offzone.Heatfluxonfintipsintheunfloodedregion,finflanks,finspacingsandfintipsinthefloodedregionwereanalyzedrespectively.COndensationonfintipsinemphasizedbyconsideringthevariationoffilmthicknessalongcircumferenceaswellashorizontally.FInefficiencywasconsideredincalculation.Thepredictionresultswerecomparedwithseveralresearchers'experimentaldataforthreekindsofworkingfluidsonsevendifferenttubegeometriesandforvarioustemperaturedifferences,Thesedataunderabout60testconditionswerepredictedwithdiscrepancyof±10%.PredictionbythepresentmodelforsteamandR-113condensationwerecomparedwithpreviousmodels.

  • 标签: 冷凝器 单水平矩形散热管 设计模型
  • 简介:Hydrodynamicandthermalcharacteristicsinapipewithsinusoidalwavysurfaceforsteadylaminarflowareinvestigatednumericallyinthepresentstudy.TheintegralformsofgoverningequationsarediscretizedusingcontrolvolumebasedFinitevolumemethodwithcollocatedvariablearrangement.SIMPLEalgorithmisusedandTDMAsolverisappliedforsolutionofsystemofequations.Apipeoflengthequalto4λisconsidered.Effectofsurfacewaviness,determinedbywavelength-amplituderatioλ/a(=L^*),onflowandthermalfieldispresented.ThesimulationworkhasbeencarriedoutforL^*=11.0-30.0foraReynoldsnumberrange50to2000.Resultsarepresentedintheformofstreamfunction,isothermallines,velocityandvorticityprofiles,changeofmeanfrictionfactor,variationinskinfriction,localandaverageNusseltnumberwithReynoldsnumber,wavenumber(n)andL^*.Foraparticulargeometry,lengthofcirculationzoneincreaseswithreynoldsnumberandapproachesalimitingvalueforhigherReynoldsnumber.Wallshearstressinthebulgepartofthechannelshowssmallervaluesthataffectlargely.therateofheattransferandNusseltnumbershowsminimumvaluesinthisregion.Thiscirculationzonedrasticallyincreaseswiththeincreaseofsurfacewavinessshowinghighmeanfrictionfactorperwavelength.MeanfrictionfactorinverselyvarieswithReynoldsnumber.Acorrelationisproposedforcalculatingfrictionfactorintheformf=C/(Re)^m,where‘C’and‘m’representstwopolynomialsofdegree4and2respectivelyandarefunctionofL^*.Higherwavinessofthesurfaceshowsthehigherheattransferratethanlowerwaviness.Heattransferratefallsalmostexponentiallyalongtheaxialdirectionwiththeincreaseofwavenumber.

  • 标签: 流体 波形管 热交换 特征
  • 简介:Thephenomenonofearingisinvestigatedinthepresentstudybasedonthetheoryofcrystalplasticitywiththedynamicexplicitfiniteelementprogramdeveloped.FirstlytextureanalysisiscarriedoutofrolledaluminiumalloyA15052bymeansofX-raytechnique.Thenfromthetexturecoefficientsananalyticalexpressionfortheorientationdistributionfunction(ODF)isderivedmakinguseofthecomputeralgebraiclanguageMathematica4.0,whichmakesiteasiertodiscretizetheODFintoaseriesofEuleriananglesrepresentingthedistributionoflatticesandfurtherthepreferredorientation(texture)ofcrystalsoftheoriginalsheets.Forthepolycrystalmodel,thematerialisdescribedusingcrystalplasticitywhereeachmaterialpointinthesheetisassumedtobeapolycrystallineaggregateofaverylargenumberofface-centeredcubic(FCC)grainswitheachgrainmodelledasanFCCcrystalwith12distinctslipsystems.ThemodifiedTaylortheoryofcrystalplasticityisusedandonlytheinitialtextureistakenintoconsiderationduringlargeplasticdeformation.Numericalsimulationofearinghasbeenperformedforanaluminiumsheetwithtextureandonewithcrystalsexhibitingrandomdistributiontodemonstratetheeffectoftextureofmaterialsontheirplasticanisotropyandformability.

  • 标签: EARING 质地 取向分发功能(ODF )
  • 简介:平淡的波浪重叠途径不能在一块协调的声学的地的重建和预言被使用,因为分开单个来源产生的压力是不可能的。根据协调的声学的地的重叠理论,一个新奇方法基于联合波浪重叠途径被开发重建并且由造匹配在全息图表面和来源之间的矩阵的联合压力预言协调的声学的地。方法能重建个人的表面的声学的信息采购原料,并且预言也从每来源和全部的协调的声学的地罐头散发的声学的地自发地被计算是可能的。试验性、数字的模拟结果证明这个方法能有效地解决holographic重建和协调的声学的地的预言,它能也被用作一种协调的声学的地分离技术。这个新奇方法上的学习扩大声学的雷射摄影术技术的应用程序范围。

  • 标签: 重建 预测 连贯声场 组合波 重叠逼近
  • 简介:Inthispaperwestudytheproximalpointalgorithm(PPA)basedpredictioncorrection(PC)methodsformonotonevariationalinequalities.Eachiterationofthesemethodsconsistsofapredictionandacorrection.ThepredictorsareproducedbyinexactPPAsteps.ThenewiteratesarethenupdatedbyacorrectionusingthePPAformula.Wepresenttwoprofitfunctionswhichservetwopurposes:Firstweshowthattheprofitfunctionsaretightlowerboundsoftheimprovementsobtainedineachiteration.Basedonthisconclusionweobtaintheconvergenceinexactnessrestrictionsforthepredictionstep.Secondweshowthattheprofitfunctionsarequadraticallydependentuponthesteplengths,thustheoptimalsteplengthsareobtainedinthecorrectionstep.Inthelastpartofthepaperwecomparethestrengthsofdifferentmethodsbasedontheirinexactnessrestrictions.

  • 标签: 计算方法 最接近点计算法 预测方法 变量 不等式
  • 简介:Theinitial-boundaryvalueproblemofBurgersequationisconsidered.Aprediction-correctionLegendrespectralschemeisproposed.Itpossessestheaccuracyofsecondorderintimeandhigherorderinspace.Thenumericalexperimentsshowthehighaccuracyofthisapproach.

  • 标签: Unsteady burgers equation prediction-correction LEGENDRE SPECTRAL
  • 简介:Withrespecttoobtainingtheeffectiveelasticmoduliofthecomposite,thepresenttheorydif-fersfrombothEshelby’sequivalentinclusionmethodandHill’sself-consistentone,bothofwhichonlyconsid-erthemechanicalpropertiesofthematrixandinclusions(fibers).Infact,theinclusion-inclusioninteractionismorepronouncedwhenthevolumefractionofinclusionsofthecompositeincreases.Hence,inthispapertheeffectiveelasticmoduliofthecompositearederivedbytakingintoaccounttheshapes,sizesanddistributionofinclusions,andtheinteractionsbetweeninclusions.Inaddition,itismoreconvincingtoassumeshort-fibersascylindricalinclusionsasinthepresentpaperthanasellipsoidalonesasinothers.Finally,numericalre-sultsaregiven.

  • 标签: microstructure CYLINDRICAL INCLUSION EFFECTIVE ELASTIC MODULI
  • 简介:ppΛ→pK~+Λ的反应。是一条很好的隧道通过他们的KΛ腐烂模式学习N~*回声,因为没有混合isospin我=1/2并且我=3/2due到isospin保存。在这个工作,我们扩大一个回声模型,它能复制全部的生气的节很好,到提议这反应的微分生气的节信息。它能用作一本参考书在Lanzhou更凉爽的存储戒指(CSR)造安排强子察觉者。在未来的这些微分生气的节的实验测量将供应我们模型和帮助上的更多的限制我们更好理解奇妙生产动力学。

  • 标签: 谐振模型 PP碰撞 理论物理 交叉段
  • 简介:为了解决非线性的补充问题(NCP),在每次重复,当时,古典近似的点算法解决调节得好的sub-NCP对数--二次近似(LQP)方法解决非线性的方程(LQP系统)的一个系统。这份报纸论述实际LQP为NCP的基于方法的预言修正方法。预言者经由在显著地放松的限制下面近似解决LQP系统被获得,并且新重申(修正者)被从原来的LQP方法导出的一个明确的公式直接计算。实现是很容易的被执行。方法的全球集中在象原来的LQP方法的一样的温和假设下面被证明。最后,交通平衡问题的数字结果被提供证实方法为一些实际问题是有效的。[从作者抽象]

  • 标签: 对数 近点法 线性互补问题 预测校正 LQP系统