学科分类
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401 个结果
  • 简介:作者在H2(Bn)上给一个作文操作符的必要标准的上面的界限,它在S.S定义的更高维的值分发理论包含数的函数。Chern。一个标准也被给保证H2(Bn)上的作文操作员被围住或压缩。

  • 标签: 复合算子 本性范数 BN H2 上界 值分布理论
  • 简介:Inthispaper,theconceptofthes-doublydiagonallydominantmatricesisintroducedandthepropertiesofthesematricesarediscussed.Withthepropertiesofthes-doublydiagonallydominantmatricesandthepropertiesofcomparisonmatrices,someequivalentconditionsforH-matricesarepresented.TheseconditionsgeneralizeandimproveexistingresultsabouttheequivalentconditionsforH-matrices.Applicationsandexamplesusingthesenewequivalentconditionsarealsopresented,andanewinclusionregionofk-multipleeigenvaluesofmatricesisobtained.

  • 标签: H-矩阵 S-双对角占优矩阵 余角 高斯变换
  • 简介:LinuxbasednetworkedPCsclustersarereplacingboththeVMEnonuniformdirectmemoryaccesssystemsandSMPsharedmemorysystemsusedpreviouslyfortheonlineeventfilteringandreconstrucion.ToallowanoptimaluseofthedistributedresourcesofPCclustersanopensoftwareframeworkispresentlybeingdevelopedbasedonadataflowparadigmforeventprocessing.Thisframeworkallowsforthedistributionofthedataofphysicseventsandassociatedcalibrationdatatomultiplecomputersfrommultipleinputsourcesforprocessingandthesubsequentcollectionoftheprocessedeventsatmultipleoutputs.Thebasisofthesystemistheeventrepository,basicallyafirst-infirst-outeventstorewhichmaybereadandwritteninamannersimilartosequentialfileaccess.Eventsarestoredinandtransferredbetweenrepositoriesassuitablylargesequencestoenablehighthroughput.Multiplereaderscanreadsimultaneouslyfromasinglerepositorytoreceiveeventsequencesandmultiplewriterscaninserteventsequencestoarepository,Hencerepositoriesareusedforeventdistributionandcollection.Tosupportsynchronisationoftheeventfolowtherepositoryimplementsbaaiers.Abarriermustbewrittenbyallthewritersofarepositorybeforeanyreadercanreadthebarrier,Areadermustreadabarrierbeforeitmayreceivedatafrombehindit.Onlyafterallreadershavereadthebarrieristhebarrieremovedfromtherepository.Abarriermayalsohaveattacheddata,Inthiswaycalibrationdatacanbedistributedtoallproessuingunits.Therepositoriesareimplementedasmulti-threadedCORBAobjectsinC++andCORMAisusedforalldatatransfers,JobsetupscriptsarewritteninpythonandinteractivestatusandhistogramdisplayisprovidedbyaJavaprogram.JobsrununderthePBSbatchsystemprovidingshareduseofresourcesforonlinetriggering,offlinemassreporcessinganduseranalysisjobs.

  • 标签: H1实验 数据流 数据处理
  • 简介:ThisarticleobtainsanexplicitexpressionoftheheatkernelsonH-typegroupsandthenfollowtheestimateofheatkernelstodeducetheHardy'suncertaintyprincipleonthenilpotentLiegroups.

  • 标签: 不确定性原理 类型分析 热核函数 数学
  • 简介:<正>在初中数学中与"动"有关的问题一般都是教学中的难点,而这类问题对培养学生的思维品质和各种能力都有很大的促进作用.新课程实施以来,很多省、市的中考题中都以"动态几何题"作为压轴题,以2007年的全国各地的中考试题为例,约有70%的省市的中考试题中有动态几何题,以压轴题出现的约占43%.动态几何题是研究在几何图形的运动中,伴随着出现一定的图形位置、数量关系的"变"与"不变"性.这类试题集代数与几何的众多知识于一体,赋运动、开放、探索于一题,并且渗透了分类讨论、数形结合等数学思想方法,因此,它具有很

  • 标签: 数学思想方法 中考试题 分类讨论 数量关系 集代数 数形结合
  • 简介:利用2-羟甲基吡啶(Hhmp)、三乙胺和Mn(CH3COO)2在室温下反应,合成了2D分子基磁性配位聚合物[Mn3Ⅱ(CH3COO)6(H2O)4·(H2O)2]n,其结晶为单斜空间群P21/c.在标题化合物中,Mn2+通过乙酸根离子连接形成线性三核Mn3(CH3COO)6单元;这些单元进一步通过乙酸根离子连接形成1个具有4-连接节点的二维层状44拓扑结构;最后,层与层之间通过氢键连接形成3D超分子网络结构.磁性研究表明,由于缺少反转中心,标题化合物在低温时表现出自旋倾斜反铁磁有序,这在纯乙酸基团构筑的体系中比较少见.

  • 标签: 配合物 晶体结构 磁性 自旋倾斜
  • 简介:Thecopper(Ⅱ)complex[Cu3(nta)2(azpy)2(H2O2)]·6H2O(nta=nitrilotriacetate,azpy=4,4′-azobispyridine)hasbeensynthesizedandcharacterized.TheX-rayanalysisrevealsthattherearetwokindsofcopper(Ⅱ)coordinationenvironments.Cu(1)hasadistortedsquareplanesymmetryandCu(2)hasadistortedoctahedralsymmetry.Cu(1)islinkedtoCu(2)throughntaandboundtoCu(1C)byazpy,andCu(2)islinkedtoCu(2A)throughazpy,whichextendstotwo-dimensionalnetworkwithlargerhombus1.2nm×1.7nm.

  • 标签: 合成 结构 二(次氮基三乙酸酯)二(偶二嘧啶酰胺)二水三铜络合物
  • 简介:借助密度泛函理论,用B3LYP和BP86方法,对一系列潜在的新型高能密度材料分子H2N5MN5H2(M=Be,Mg,Ca,Zn,和Cd)进行了理论预测研究.结果表明,这些材料分子都非常稳定,不容易分解,其中H2N5MN5H2最稳定.金属离子的配位作用对化合物的稳定起了重要作用.配体H2N5也因从金属M获得一个电子变成H2N^-离子而变得更稳定.

  • 标签: 高能密度材料 密度泛函理论 稳定性
  • 简介:AbinitiomolecularorbitalcalculationsofdoublynegativechargedB16H162-(D2)andneutralB16H16(Td)havebeendoneattheHF/6-31Glevel.TheyarepredictedtobechemicallyandkineticallystablebyvibrationalanalysesontheirrespectiveenergyhypersurfaceoftheHF/6-31Glevel.ThegeometricalstructureofthespeciesB16H1622-(D2)wasdiscussed.

  • 标签: Closo BORON hydrides ab INITIO MOLECULAR
  • 简介:从海南中考数学的试题命题来看,第24题主要考查的是函数与几何的综合应用试题,做为压轴题,本题一般都设3—4个问题,第(1)题容易上手,第(2)题中等难度,但一般还是属于常规题型,第(3)、(4)题较难,对学生的能力要求较高,探索性较强.试题呈现“起点低,坡度缓,尾巴略翘”的原则,本题涉及的知识点比较多,综合性强,具体考查的知识点有:“二次函数、一次函数、一元二次方程、平行四边形、三角形、线段垂直平分线、勾股定理、相似三角形”等知识,及动态几何问题中函数关系的建立、应用.

  • 标签: 考点分析 数学 中考 相似三角形 一元二次方程 二次函数
  • 简介:Yb3+complexeswithtwonitrilotriaceticacidmoleculeswerepreparedandtheircompositionsweredeterminedasK3[Yb(nta)2(H2O)]*5H2OandNa3[Yb(nta)2]*6H2Obyelementalanalyses.Theirstructureswerecharacterizedbysingle-crystalX-raydiffractionanalyses.IncomplexK3[Yb(nta)2(H2O)]*5H2O,theYbN2O7partformsanine-coordinatemonocappedsquareantiprismaticstructure.IncomplexNa3[Yb(nta)2]*6H2O,theYbN2O6partformsaneight-coordinatesquareantiprismaticstructure.Itcanbeseenthattheoutercations(K+andNa+)greatlyaffectthecoordinationnumberandcoordinatestructurefromtheseresults.

  • 标签: 次氮基三乙酸 镱配合物 合成 晶体结构 X射线衍射
  • 简介:Thispaperreportsthattheetchingmorphologyofdislocationsin8°off-axis4H-SiCepilayerisobservedbyusingascanningelectronicmicroscope.Itisfoundthatdifferenttypesofdislocationscorrespondwithdifferentdensitiesandbasalplanedislcation(BPD)arrayandthreadingedgedislocation(TED)pileupgroupliealongsomecertaincrystaldirectionsintheepilayer.Itisconcludedthattheelasticenergyofthreadingscrewdislocations(TSDs)ishighestandTEDsislowestamongthesedislocations,sothedensityofTSDsislowerthanTEDs.TheBPDscanconverttoTEDsbutTSDscanonlypropagateintotheepilyerinspiteofthehigherelasticenergythanTEDs.ThereasonoftheformofBPDsarrayinepilayeristhatthebigstepalongthebasalplanecausedbyfacedefectsblockedtheupstreamatoms,andTEDspileupgroupisthatthedislocationsslideisblockedbydislocationgroupsinepilayer.

  • 标签: 刃型位错 外延层 SiC 离轴 扫描电子显微镜 逃生装置
  • 简介:我们从氢的现在的泛音系列有不同电离精力Ip的分子的离子。由从氦离子和氢比较再结合矩阵元素分子的离子,我们证实在高顺序的泛音产生的干扰效果从再结合干扰发源。在仅仅当准确连续统wavefunction被使用时,o=Ek+Ip举行的1D表演的再结合矩阵元素上的数字研究,和在泛音系列的极值的职务能精确地被预言。我们证明在泛音系列的极值的职务被围住再结合干扰的潜在的依赖主要影响。[从作者抽象]

  • 标签: 高次谐波产生 氢分子离子 氢气 作者 干扰效应 矩阵元素
  • 简介:该型测量组合导航系统是在装船使用4年取得较好效果的情况下,于1993年2月通过部级技术鉴定,本文概要介绍了主要功能、技术途径、硬件设计特点、软件设计概况及数据处理技术,并综述了海上试验与试用情况等技术资料。

  • 标签: 组合导航系统 远海测量 数据采集接口 数学模型 导航定位 定位精度
  • 简介:ThenotionsoffuzzydotidealsandfuzzydotH-idealsinBCH-algebrasareintro-duced,severalappropriateexamplesareprovided,andtheirsomepropertiesareinvestigated.Therelationsamongfuzzyideal,fuzzyH-ideal,fuzzydotidealandfuzzydotH-idealsinBCH-algebrasarediscussed,severalequivalentdepictionsoffuzzydotidealareobtained.Howtodealwiththehomomorphicimageandinverseimageoffuzzydotideals(fuzzydotH-ideals)arestudied.Therelationsbetweenafuzzydotideal(fuzzydotH-ideal)inBCH-algebrasandafuzzydotideal(fuzzydotH-ideal)intheproductalgebraofBCH-algebrasaregiven.

  • 标签: 代数 模糊数学 同态现象 数学分析
  • 简介:TheauthorsconsiderthescatteringphenomenaofthedefocusingH~s-criticalNLS.ItisshownthatifasolutionofthedefocusingNLSremainsboundedinthecriticalhomogeneousSobolevnormonitsmaximalintervalofexistence,thenthesolutionisglobalandscatters.

  • 标签: 整体适定性 散焦 散射 SOBOLEV 时间间隔 NLS
  • 简介:Catalyticcombustionofpropane-airmixturewasinvestigated.Platinumcatalystsoveraflatstainlesssteelwithγ-aluminawashcoatwereemployed.Theemployedburnerhasthreecatalystssetparalleltothemixtureflow,spacedatanintervalof5,10and15mm.Bothexperimentandnumericalsimulationweremadeatinlettemperatureof553K,inletvelocityof3to7m/sandequivalenceratioof0.3to0.5.Inthenumericalsimulation,two-dimensional,steadystatemodelwasdevelopedtocalculatethetemperatureandspeciesconcentrationingas-phase.Inthismodel.chemicalreactiononthecatalystsurfaceandthatinthegasphasewereassumedtooccurinthree-steps.Thenumericalresultsshowgoodagreementwithexperimentalresults.Itwasfoundthatthepropertiesofthecatalyststronglyaffectthecatalystsurfacetemperature.Especially,thethermalconductivityofcatalysthasagreateffect,whiletheemissivityofcatalysthaslesseffect.

  • 标签: 燃气透平 催化燃烧 C3H8-空气混合
  • 简介:Usingtherecentlydevelopedfinite-basis-setmethodwithBsplines,excitedstatesofHatomsinamagneticfieldhavebeencalculated.Energylevelsarepresentedforthetenexcitedstates,2s_0,3d′_0,3p_0,3d_(-1),3d_(-1),4d_(-1),3d_(-2),4d_(-2),4f_(-2),and5f_(-2)asafunctionofmagneticfieldstrengthswitharangefromzeroupto2.35×10~6T.Theobtainedresultsarecomparedwithavailablehighaccuracytheoreticaldatareportedintheliteratureandfoundtobeinexcellentagreement.Thecomparisonalsoshowsthatthecurrentmethodcanproduceenergylevelswithanaccuracyhigherthantheexistinghighaccuracymethod[Phys.Rev.A54(1996)287].Herehighaccuracyenergylevelsareforthefirsttimereportedforthe3d′_0,4d_(-1),4d_(-2),4f_(-2),and5f_(-2)states.

  • 标签: 原子激发态 精度计算 能量水平 氢原子 磁场 数据精度
  • 简介:ThenewH.264videocodingstandardachievessignificantlyhighercompressionperformancethanMPEG-2.AstheMPEG-2ispopularindigitalTV,DVD,etc.,bandwidthormemoryspacecanbesavedbytranscodingthosestreamsintoH.264intheseapplications.Unfortunately,thehugecomplexitykeepstranscodingfrombeingwidelyusedinpracticalapplications.Thispaperproposesanefficienttranscodingarchitecturewithasmartdownscalingdecoderandafastmodedecisionalgorithm.Usingtheproposedarchitecture,hugebufferingmemoryspaceissavedandthetranscodingcomplexityisreduced.Performanceoftheproposedfastmodedecisionalgorithmisvalidatedbyexperiments.

  • 标签: 图像通信 视频自动译码 代码转换机 电子技术