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27 个结果
  • 简介:1.Tcetonicandmagmaticactivizationproeesscs(tcetonicandthermalregenerationofancientbasc-mentordiwa)occurrcdinPhancrozoicanda1soil1Prccan1briantimc.Activizationrcgin1csbccamcap-parcntalrcadyinArchcantimcandthcirimportanccsignificantlyincrcascdduringLatcProtcrozoicpcri-odwhcnmanypartsofArchcancrustwcrc

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  • 简介:统一通信联络中心解决方案提供商Aspect软件公司与电信服务供应商AireSpring日前共同宣布,成功地实现了Aspect基于会话初始协议(SIP)的联络中心解决方案与AireSpring的SIPTrunking(SIP中继)产品间的互用性。

  • 标签: ASPECT 互用性 SIP 会话初始协议 通信联络 服务供应商
  • 简介:象kinematics一样的形态学是在flapping飞行的性能的一个批评决定因素。在bio-flyers的气体动力学上理解结构的特点的效果,有在翼尖的1,2,和4表现象徘回一样正弦曲线kinematics的方面比率(AR)的三个矩形的翅膀基于雷纳兹数字5300试验性地被调查。沿着翅膀跨度的部分切割上的流动结构被比较。更强壮的K-H不稳定性与更高的方面比率在翅膀的前缘旋涡上被发现。旋涡爆炸仅仅出现在high-aspect-ratio翅膀的外部spanwise地点上。在high-aspect-ratio翅膀上爆炸的旋涡也许是为什么的原因之一bio-flyers通常有low-aspect-ratio翅膀。除了当旋涡爆炸发生时,定量分析在更高的方面比率翅膀上展出前缘旋涡(LEV)的更大的无尺寸的循环。沿着跨度的AR1和AR2的平均无尺寸的发行量几乎在50%跨度等于无尺寸的发行量。流动结构和发行量分析证明正弦曲线kinematics与在类似的研究使用的简化flappingkinematics相比压制LEV的故障。在在当前的Re范围,全面流动结构不对雷纳兹敏感的AR4表演的雷纳兹数字效果结果数。

  • 标签: 空气动力学效应 长宽比 扑翼 运动学性能 雷诺数效应 飞行
  • 简介:Thecomputationalproblemsoftwospecialdeterminantsareinvestigated.Thosedeterminantsappearintheconstructionofthefunction-valuedPade-typeapproximationforcomputingFredholmintegralequationofthesecondkind.Themaintooltobeusedinthispaperisthewell-knownSchurcomplementtheorem.

  • 标签: 函数值Padé逼近 计算问题 行列式 Schur余角定理
  • 简介:Aspect-orientedprogrammingmodularizescrosscuttingconcernsintoaspectswiththeadviceinvokedatthespecifiedpointsofprogramexecution.Aspectscanbeusedinaharmfulwaythatinvalidatesdesiredpropertiesandevendestroystheconceptualintegrityofprograms.Toassurethequalityofanaspect-orientedsystem,rigorousanalysisanddesignofaspectsarehighlydesirable.Inthispaper,wepresentanapproachtoaspect-orientedmodelingandverificationwithfinitestatemachines.Ourapproachprovidesexplicitnotations(e.g.,pointcut,adviceandaspect)forcapturingcrosscuttingconcernsandincrementalmodificationrequirementswithrespecttoclassstatemodels.Forverificationpurposes,wecomposetheaspectmodelsandclassmodelsinanaspect-orientedmodelthroughaweavingmechanism.ThenwetransformthewovenmodelsandtheclassmodelsnotaffectedbytheaspectsintoFSP(FiniteStateProcesses),whicharetobecheckedbytheLTSA(LabeledTransitionSystemAnalyzer)modelcheckeragainstthedesiredsystemproperties.Wehaveappliedourapproachtothemodelingandverificationofthreeaspect-orientedsystems.Tofurtherevaluatetheeffectivenessofverification,wecreatedalargenumberofflawedaspectmodelsandverifiedthemagainstthesystemrequirements.Theresultsshowthattheverificationhasrevealedallflawedmodels.Thisindicatesthatourapproachiseffectiveinqualityassuranceofaspect-orientedstatemodels.Assuch,ourapproachcanbeusedformodel-checkingstate-basedspecificationofaspect-orienteddesignandcanuncoversomesystemdesignproblemsbeforethesystemisimplemented.

  • 标签: 有限状态机 验证 建模
  • 简介:AbstractInthispaperwestudysomenonoverlappingdomaindecompositionmethodsforsolvingaclassofellipticproblemsarisingfromcompositematerialsandflowsinporousmediawhichcontainmanyspatialscales.Ourpreconditionerdiffersfromtraditionaldomaindecompositionpreconditionersbyusingacoarsesolverwhichisadaptivetosmallscaleheterogeneousfeatures.Whiletheconvergencerateoftraditionaldomaindecompositionalgorithmsusingcoarsesolversbasedonlinearorpolynomialinterpolationsmaydeteriorateinthepresenceofrapidsmallscaleoscillationsorhighaspectratios,ourpreconditionerisapplicabletomultiple-scaleproblemswithoutrestrictiveassumptionsandseemstohaveaconvergenceratenearlyindependentoftheaspectratiowithinthesubstructures.ArigorousconvergenceanalysisbasedontheSchwarzframeworkiscarriedout,andwedemonstratetheefficiencyandrobustnessoftheproposedpreconditionerthroughnumericalexperimentswhichincludeproblemswithmultipl

  • 标签: Multiscale ELLIPTIC PROBLEMS DOMAIN DECOMPOSITION SCHWARZ
  • 简介:CUTTINGDOWNORCHARDSINASSYRIANROYALINSCRIPTIONS—THEHISTORIOGRAPHICASPECT①B.Oded,UniversityofHaifaCutingdowntresingardens(kir^a...

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  • 简介:面试成功的关键因素不是你的经验或学历,不是你所学的课程或你所选的课外活动,也不是任何其他的基本资历,这些只是证明你有资格参加面试而已,面试成功的关键因素可以总结为两个字,那就是:态度。如果你想胜过在经验、学历或其他方面比你有优势的人,

  • 标签: 面试 成功 关键因素 学历 资历 经验
  • 简介:ByECHunderasteadyB_vfield,aclosedfieldequilibriumofalowaspectratioaslowasR/a=1.4isspontaneouslyformedintheLATEdevice.Afterthespontaneousformation,theplasmacurrenthasincreasedfurtheruptoI_P=7.2kAby2.45GHz,30kWandI_P=11kAby5GHz,120kW,byincreasingthemicrowavepowerwithaslowrampofB_vfortheequilibriumoftheplasmaloopatlargercurrents.Bothamountto12%ofthetotaltoroidalcoilcurrent.ECH/ECCDat2udharmonicresonanceofEBWsupportstheplasma.Anoutlineofthetheoreticalconsiderationsfortheformationprocessispresented.

  • 标签: ECH 球形托卡马克装置 自发构成 等离子体 稳定性
  • 简介:Wehavestudiedtheelectronic,bondingandenergeticcharacteristicsoftheFe-Sibinarysystemusingthetight-bondingextendedHuckelmethod.AmongtheFe-Sibinarycompounds,FeSihasthemostsymmetricgeometricarrangementinthecrystalstructure.Italsopossessesthelargestcohesiveenergyperatom.ThiscorrelatestothefactthatFeSiisthemoststablecongruently-meltingcompoundinthebulkphasediagram.Anestimateofinteractionenergiesbetweendifferentatomsisalsogiven.

  • 标签: FE-SI BINARY system BONDING EXTENDED Huckel
  • 简介:Poly(N-vinyl-2-pyrrolidone)(PVP)-stabilizedrutheniumnanorodswithhighaspectratiobyrefluxingruthenium(Ⅲ)chlorideinn-propanolhavebeensuccessfullypreparedbymeansofafacileandrapidmicrowaveheatingforthefirsttime.Thestructureandmorphologyoftheobtainedproductswerecharacterizedbytransmissionelectronmicroscopy(TEM),selectareaelectrondiffraction(SAED),ultraviolet-visiblespectrophotometry(UV-vis),X-rayphotoelectronspectroscopy(XPS)andFouriertransformspectroscopy(FT-IR).XPSanalysisrevealsthatthenanorodswereinthemetallicstate.TEMimagesshowedthatrutheniumnanorodshadanobviousone-dimensionalstructurewiththeaspectratiorangedfrom5to40nmandlengthupto600nm.SAEDpatternsindicatedthatthenanorodsweresingle-crystallinewithahexagonalstructure.

  • 标签: Poly(N-vinyl-2-pyrrolidone) RUTHENIUM NANORODS MICROWAVE
  • 简介:AnewconceptaboutthenextsteptokamakdeviceisrecentlyproposedbyacademicianLIZhengwu.HeindicatedthandevicewiththeaspectratioAnear2isablankinboththepresent-daytokamakdevicesandtheproposedorinconstructiontokamaks,includingtheITER-FEAT.

  • 标签: 托卡马克 聚变反应堆 中心等离子体 纵横比
  • 简介:Theheattransferfromanelectricallyheatedcylinder(wire)offinitelengthtothesurroundingfluidcanbedividedintoheatradiation,conductionandconvection.Atechnicalapplicationofthesecylinderswithtypicaldimensionsof1-2mmlengthandafewmicrometersdiameteristheHot-Wire-Anemometry.Thissystematicstudyshouldclarifytheinfluenceoffreeconvectiontothreedimensionalheattransferofcylinders.forthisaimitisplannedtoinvestigateReynoldsnumbersbelowRe=1(creepingflow).Forthisreasonmeasurementsshouldbedoneunder1gintheearthlaboratoryandalsoundermicrogravity(μg)conditions.Comparisonsofthesemeasurementsunderotherwisesameconditionsallowstodistinguishbetweenthepureconvectionheattransferandthecontributionsduetoconductionandothereffects.FormeasurementsunderμgtheDropTowerBremencanbeusedasresearchfacility.DuetothefastresponseofconvectiontochangesinthegravityconditionstheDropTowerisanidealandcostefficientexperimentaltool.Theexperimentalsetupisbuildtooperateatvelocityrangeof0-1m/swhichincludesthewholerangeofconvectionfrompurefreeconvectionat0m/sovermixedconvectionuptopureforcedconvectionatvelocitiesaboveabout0.15m/s.ThisvelocityregioncorrespondstoarangeoftheReynoldsnumberofRe=0-0.18foracylinderof5μmdiameteratTf=140℃inairatanambienttemperatureofabout21℃.

  • 标签: 热传导 自由对流 效应研究
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