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30 个结果
  • 简介:ThefundamentalsolutionsoftheorthotropicthickplatestakingintoaccountthetransversesheardeformationarederivedbymeansofHrmander’soperatormethodandaplane-wavedecompositionoftheDiracδ-functioninthispapey.Theboundaryintegralequationsofthethickplateshavebeenformulatedwhichareadaptedtoarbitraryboundaryconditionsandplaneforms.Thenumericalcalculationofthefundamentalsolutionsisdiscussedindetail.SomenumericalexamplesareanalyzedwithBEM.

  • 标签: ORTHOTROPIC THICK PLATES FUNDAMENTAL solutions BEM
  • 简介:Amethodhasbeendevisedtoanalyzemultilayerelectricallythickcircularmi-crostripantennaexcitedbyaprobe.Thecurrentontheprobeistakentobeuniform.Thismethodwasverifiedbyanalysisandexperimentofanelectricallythickcircularmicrostripan-tennawithanairgap.BasedonthefreespaceelectricdyadicGreen’sfunction,thefieldexpressionofanhorizontalelectricdipole(HED),whichislocatedatanypointofthemultilayermediaandpointsinanydirection,hasbeenderived.ByusingthisfieldexpressionandtheRichmondre-actionequation,anintegralequationintermsofelectriccurrentonthepatchisformulated.Byproperlychoosingcurrentexpansionmodes,thismethodcanbeusedforanelectricallythickmi-crostripantenna.Thetheoreticalresultsagreeverywellwithexperimentaldataforanelectricallythickcircularmicrostripantennawithanairgap.

  • 标签: ANTENNA MICROWAVE ANTENNA MULTILAYER SUBSTRATE
  • 简介:摘要:Thick translation是文化、文学经典跨文化翻译的一种重要途径,其研究在国内外都是较新的领域。国内近二十年产生了一批相关成果,其中个案研究居多,且存在概念的误读误用,多个译名混用的现象,理论深度和研究方法有待加强。在深入有关thick translation的理论研究的基础上,未来研究趋向在于深化其描写性和规定性研究,以促进该理论的健康发展,有效发挥其描写和解释翻译现象,评价和指导翻译实践的作用。

  • 标签: thick translation 文化典籍 翻译策略
  • 简介:在这篇论文,以便预言厚球形的结构的剩余变丑,一个焊接程序基于Ansys用APDL语言被编译,一个焊接例子的一个数字焊接实验被执行。焊接的温度领域第一被模仿,然后,热结构的联合分析被执行,并且最后,在焊接以后的剩余压力和变丑被得到。在那以后,数字实验结果与物理实验相比是一个。数字模拟与物理实验适合很好的比较分析表演。根据那,厚球形的壳结构的一个三维的数字实验被执行在焊接期间得到应力的变化规则和厚球形的壳结构的变丑。研究具有到用机器制造的剩余变丑和高精确的预言的大价值。

  • 标签: 数字焊接 焊接程序 热结构耦合分析 残差应力
  • 简介:Weinvestigateeffectsofannealingonmagneticpropertiesofathick(Ga,Mn)Aslayer,andfindadramaticincreaseoftheCurietemperaturefrom65to115Kbypostgrowthannealingfora500-nm(Ga,Mn)Aslayer.AugerelectronspectroscopymeasurementssuggestthattheincreaseoftheCurietemperatureismainlyduetodiffusionofMninterstitialtothefreesurface.Thedouble-crystalx-raydiffractionpatternsshowthatthelatticeconstantof(Ga,Mn)Asdecreaseswithincreasingannealingtemperature.Asaresult,theannealinginducedreductionofthelatticeconstantismainlyattributedtoremovalofMninterstitial.

  • 标签: 铁磁半导体 退火效应 磁性构造 薄膜厚度
  • 简介:Inthispaper,amethodofconstructingdisplacement-basedelmentforthick/thinplatesisdevel-opedbyusingthetechniqueofgeneralizedcompatibility,andarectangulardisplacement-basedelementwith12degreesoffreedomforthick/thinplatesispresented.Thismethodenjoysagoodaccuracywithsimpleformulationandisfreeofshear-lockingasthethicknessoftheplateapproacheszero.

  • 标签: THICK PLATE THIN PLATE GENERALIZED compatibility
  • 简介:一个网孔为解决中等厚的盘子的有弹性的动态问题的更少的本地光线的点插值方法(LRPIM)在这篇论文被介绍。板的discretized系统方程用一个局部地加权的剩余方法被获得。它使用一个光线的基础功能(RBF)作为试用功能,和使用结合了多项式基础功能是的四次的花键功能加权的剩余方法的测试功能。形状功能有Kronecker三角洲功能,和没有另外的处理的性质被做强加必要边界条件。为解决动态问题的Newmark方法在计算被采用。动态性质上的照子域和影响领域的尺寸的效果被调查。数字结果证明介绍方法能为中等厚的板的有弹性的动态问题给相当精确的结果。

  • 标签: 弹性动力分析 中厚板 无网格 TIAL金属间化合物 NEWMARK法 加权残值法
  • 简介:Atwo-dimensionalsteadyReynolds-averagedNavier–Stokes(RANS)equationwassolvedtoinvestigatetheeffectsofaGurneyflaponSFYT15thickairfoilaerodynamicperformance.Thisairfoilwasdesignedforflightvehicleoperatingat20kmaltitudewithfreestreamvelocityof25m/s.Thechordlength(C)is5mandtheReynoldsnumberbasedonchordlengthisRe=7.76×105.Gurneyflapswiththeheightsrangingfrom0.25%Cto3%Cwereinvestigated.Theshearstresstransport(SST)k-ωturbulencemodelwasusedtosimulatetheflowstructurearoundtheairfoil.ItisshowedthatGurneyflapcanenhancenotonlytheprestallliftbutalsolift-to-dragratioinacertainrangeofanglesofattack.Specially,atcruiseangleofattack(α=3°),Gurneyflapwith0.5%Cheightcanincreaselift-to-dragratioby2.7%,andliftcoefficientby12.9%,respectively.Furthermore,thesurfacepressuredistribution,streamlinesandtrailing-edgeflowstructurearoundtheairfoilareillustrated,whicharehelpfultounderstandthemechanismsofGurneyflaponairfoilaerodynamicperformance.Moreover,itisfoundthattheincreaseofairfoildragwithGurneyflapcanbeattributedtotheincreaseofpressuredragbetweenthewindwardandtheleewardsidesofGurneyflapitself.

  • 标签: GURNEY襟翼 翼型设计 数值模拟 STOKES 升力系数 表面压力分布
  • 简介:Theequationofstressintensityfactors(SIF)ofinternallypressurizedthick-walledcylinderwasusedasthereferencecase.SIFequationofrotatingthick-walledcylindercontainingaradialcrackalongtheinternalborewaspresentedinweightfunctionmethod.Theweightfumctionformulaswereworkedoutandcanbeusedforallkindsofdepthofcracks,rotatingspeed,material,sizeofthick-walledcylindertocalculatethestressintensityfactors.Theresultsindicatedthevalidityandeffectivenessoftheseformulas.Meanwhile,therulesofthestressintensityfactorsinrotatingthick-walledcylinderwiththechangeofcrackdepthsandtheratioofouterradiustoinnerradiuswerestudied.Thestudiesarevaluabletoengineeringapplication.

  • 标签: 重力函数 应力强度 断裂机械学 旋转柱体 边缘断裂
  • 简介:Stimulatedemissiondepletion(STED)microscopyisoneoffar-fieldopticalmicroscopytechniquesthatcanprovidesub-diffractionspatialresolution.ThespatialresolutionoftheSTEDmicroscopyisdeterminedbythespeciallyengineeredbeamprofileofthedepletionbeamanditspower.However,thebeamprofileofthedepletionbeammaybedistortedduetoaberrationsofopticalsystemsandinhomogeneityofaspecimen’sopticalproperties,resultinginacompromisedspatialresolution.Thesituationgetsdeterioratedwhenthicksamplesareimaged.Intheworstcase,theseveredistortionofthedepletionbeamprofilemaycausecompletelossofthesuperresolutioneffectnomatterhowmuchdepletionpowerisappliedtospecimens.Previouslyseveraladaptiveopticsapproacheshavebeenexploredtocompensateaberrationsofsystemsandspecimens.However,itisdifficulttocorrectthecomplicatedhigh-orderopticalaberrationsofspecimens.Inthisreport,wedemonstratethatthecomplicateddistortedwavefrontfromathickphantomsamplecanbemeasuredbyusingthecoherentopticaladaptivetechnique.Thefullcorrectioncaneffectivelymaintainandimprovespatialresolutioninimagingthicksamples.

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  • 简介:Inthispaper,theperformancecharacteristicsofASTMA19QS31803andASTMA1S2F51duplexstainlesssteelwereintroduced,andtheweldabilitieswereanalyzed.Theweldingrepairproceduresofthickwallduplexstainlesssteelweredevelopedbyweldingprocedurequalification.Researchshowsthattherepairweldinghaslesseffectonmechanicalpropertiesofweldedjointsandgreatinfluenceonphaseproportionsandpittingcorrosionresistance.Thetestresultsmeettherequirementsofprojectspecifications.Therepairweldingprocedurecanbeusedinproject,andonlyonetimerepairshallbeused.

  • 标签: DUPLEX STAINLESS steel large thickness welding
  • 简介:Bygivingupanyassumptionsaboutdisplacementmodelsandstressdistribution,themixedstateHamiltonequationfortheaxisymmetricproblemofthethicklaminatedclosedcantilevercylindricalshellsisestablished.Anidenticalanalyticalsolutionisobtainedforthethin,moderatelythickandthicklaminatedclosedcantilevercylindricalshells.Allequationsofelasticitycanbesatis-fied,andallelasticconstantscanbetakenintoaccount.

  • 标签: Hamilton CANONICAL EQUATION state EQUATION CANTILEVER
  • 简介:ThickGaNfilmsweregrownonthesapphiresubstratebyhydridevapourphaseepitaxy.ThepropertiesofGaNfilmswerefoundtobesignificantlyinfluencedbythedurationofexposingthesapphiresubstratetoammoniapriortotheGaNgrowthinitiation.ThecrystallinequalityofGaNfilmsrevealedbyhighresolutionX-raydiffractionwerestronglydependentonthenitridationtime,whichdeterminedsubstratesurfacetopography.ThedifferentnitridationschemesstronglyaffectedthemorphologyofGaNoverlayersresultingintheblueshiftofthemainexcitonicpeakinphotoluminescencespectraatroomtemperature.

  • 标签: GAN薄膜 氮化衬底 生长方法 氢化物气相外延
  • 简介:UsingtheexampleofthePHELIXhigh-energyshortpulselaserwediscussthetechnicalpreconditionstoinvestigateionaccelerationwithsubmicrometerthicktargets.Weshowhowthetemporalcontrastofthissystemwasimprovedtopreventpre-ionizationofsuchtargetsonthenanosecondtimescale.Furthermoretheinfluenceoftypicalfluctuationsoruncertaintiesoftheon-targetintensityonionaccelerationexperimentsisdiscussed.Wereporthowtheseuncertaintieswerereducedbyimprovingtheassessmentandcontroloftheon-shotintensityandbyoptimizingthepositioningofthetargetintothefocalplane.Finallywereportonexperimentalresultsshowingmaximumprotonenergiesinexcessof85MeVforionaccelerationviathetargetnormalsheathaccelerationmechanismusingtargetthicknessesontheorderofonemicrometer.

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  • 简介:Thispaperdemonstratestheplanestressstateandthestressfreethermo-elasticdeformationofFGMthickplateunderthermalloading.First,theSneddon-LocketttheoremontheplanestressstateinanisotropicinfinitethickplateisgeneralizedforacaseofFGMprobleminwhichallthermo-mechanicalpropertiesareoptionalfunctionsofdepthco-ordinate.TheproofisbasedonapplicationoftheIljushinthermo-elasticpotentialtodisplacementtypesystemofequationsthatreducesittotheplanestressstateproblem.Thenanexistenceofthepurelythermaldeformationisprovedintwoways:first,itisshownthattheuniquesolutionfulfilsconditionsofsimultaneousconstanttemperatureandlineargradationofthermalexpansioncoefficient,second,proofisbaseddirectlyonstresstypesystemofequationswhichstraightforwardlyreducestocompatibilityequationsforpurelythermaldeformationifonlystressfieldishomogeneousindomainandatboundary.Finally,coupleexamplesofapplicationtoanengineeringproblemarepresented.

  • 标签: 平面应力状态 功能梯度材料 载荷作用 厚板 自由变形 热弹性方程