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  • 简介:Westudythenormretrievalbyprojectionsonaninfinite-dimensionalHilbertspaceH.Let{e_i}_(i∈I)beanorthonormalbasisinHandW_i={e_i}~⊥foralli∈I.Weshowthat{W_i}_(i∈I)doesnormretrievalifandonlyifIisaninfinitesubsetofN.Wealsogivesomepropertiesofnormretrievalbyprojections.

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  • 简介:TheauthorsdefinetheGaussmapofsurfacesinthethree-dimensionalHeisenberggroupandgivearepresentationformulaforsurfacesofprescribedmeancurvature.Furthermore,asecondorderpartialdifferentialequationfortheGaussmapisobtained,anditisshownthatthisequationisthecompleteintegrabilityconditionoftherepresentation.

  • 标签: 三维表面 海森堡群 偏微分方程 高斯映射 可积性条件 平均曲率
  • 简介:Anticipatedbackwardstochasticdifferentialequation(ABSDE)studiedthefirsttimein2007isanewtypeofstochasticdifferentialequations.Inthispaper,weestablishageneralcomparisontheoremforABSDEs.

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  • 简介:Anovelcomplex,[Cu2(phen)(sal)(Hsal)2]n(1),wassynthesizedandstructurallycharacterized.Thebasicdimericunitsareholdbysalligandsandextendedinto1-Dnetwork.Thecarboxylategrougsofsalicylatescoordinatetothecentralioninthreedifferentcoordinationmodes:chelating,bridgingandbridging-chelating.Inthecaseofbridging-chelatingofthecarboxylategroupofthesalicylate,allthreeoxygenatomsofsalicylatearebidentatelycoordinatedtocopperion,namely,μ4-η^3bindingmode.

  • 标签: 铜络合物 合成 晶体结构 表征求意见水杨酸盐 邻二氮杂菲
  • 简介:THREE-DIMENSIONALMODELLINGFORLUBRICATIONWITHREFERENCETOHUMANJOINTSZhanJie-min(DepartmentofAppliedMechanicsandEngineering,Zhon...

  • 标签: LUBRICATION HUMAN JOINTS VISCOELASTIC fluid 3-D
  • 简介:新奇木柴堆格子结构被建议。把方法基于飞机波浪扩大(PWE),新奇木柴堆的完全的photonic乐队差距(PBG)三维(3D)有减少的对称相对的兆兆赫(THz)photonic水晶(PC)一,face-centred-tetragonal(fct)对称被改变一些结构的参数优化,thehighest乐队差距比率能到达27.61%。比作传统的木柴堆格子,novelwoodpile格子有大量充满获得高质量的PBG的比率,哪个为生产过程的providesgreater便利。新奇木柴堆3DPC将是很THz功能的部件的promisingfor材料。

  • 标签: 三维光子晶体 木料堆 晶格结构 平面波扩展
  • 简介:一个维的Bose气体是不平常的超流体。与更高空间的尺寸相对照,非古典的旋转惯性的存在直接没被连接到无穷小的杂质的无驱散的运动。最近,有原子开始了的ultracold的试验性的测试和为drag力量的量的预言由动人的障碍经历了变得可得到。这热门评论讨论在与superfluidity的四轮马车标准的关系从线性反应理论获得的drag力量。基于在之上改进了动态结构因素的分析、数字的理解,不同障碍潜力的结果被获得包括单个杂质,光格子和随机的潜力从点缀模式产生了。在随机的潜力的superfluidity的动态故障在这些系统在与安德森本地化和预言的超流体绝缘体转变的关系被讨论。

  • 标签: 超流理论 玻色气体 阻力 一维 空间维度 转动惯量
  • 简介:Thequasi-2Dmodel,takingintoaccounttheaxialvelocityprofileinthecrosssectionandneglectingtheconvectiveterminthe2-Dequation,canmoreaccuratelysimulatethewaterhammerthanthe1-Dmodelusingthecross-sectionalmeanvelocity.However,ascomparedwiththe1-Dmodel,thequasi-2Dmodelbearsahighercomputationalburden.Inordertoimprovethecomputationalefficiency,the1-Dmethodisproposedtobeusedtosolvedirectlythepressureheadandthedischargeinthequasi-2Dmodelinthispaper,basedonthefactthatthepressureheadobtainedasthesolutionofthetwo-dimensionalcharacteristicequationisidenticaltothatsolvedbythe1-Dcharacteristicequations.Theproposedschemesolvesdirectlythe1-DcharacteristicequationsforthepressureheadandthedischargeusingtheMOCandsolvesthe2-Dcharacteristicequationfortheaxialvelocitiesinordertocalculatethewallshearstress.Iftheradialvelocityisneeded,itcanbeevaluatedeasilybyanexplicitequationderivedfromtheexplicit2-Dcharacteristicequation.Inthenumericaltest,theaccuracyandtheefficiencyoftheproposedschemearecomparedwithtwoexistingquasi-two-dimensionalmodelsusingtheMOC.Itisshownthattheproposedschemehasthesameaccuracyasthetwoquasi-2Dmodels,butrequireslesscomputationaltime.Therefore,itisefficienttousetheproposedschemetosimulatethe2-Dwaterhammerflows.

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  • 简介:集中和为在一个维的设定的一个不可思议地使不安的模型问题的不连续的Galerkin(DG)方法的超级集中性质被学习。由与DG答案的适当地选择的数字踪迹,存在和唯一使用DG方法,最佳的顺序L2错误界限,和2p+i顺序数字踪迹斧子的超级集中建立了。数字结果显示DG方法不甚至在一致网孔下面生产任何摆动。数字实验证明在一致网孔下面,获得数字踪迹的一致超级集中似乎不可能。不过,对所谓的Shishkin类型的实现的感谢协调,一致2p+1顺序超级集中数字地被观察。

  • 标签: 超收敛 间断Galerkin法 一维奇异摄动 数值迹
  • 简介:Unsaturatedradionuclidemigrationexperimentswereconductedinapitinsidethetestinghall.Severaltypesofradionuclideswereusedintheexperiments.Tritiumwasusedasatracerforwatermovementinunsaturatedloess.Otherkindsofradionuclideswerealsousedinordertoobtainfundamentalparametersforradionuclidemigrationsothatfurtherenvironmentalassessmentoflow—levelradioactivewastedisposalcanbecar-riedout.Mechanismsgoverningunsaturatedflowinloess,thatis,principlesofone—waylateralflow,arepresentedqualitativelyinthispaper.Andacontinuumone—dimensionalmodelforradionuclidemigrationtestingisdevelopedbasedontheex-perimentsconductedundertheparticularconditionsatthetestsite.Thedatameasuredfromthetestswerecomparedwithsolutionsofthisone—dimensionalmodel.Resultsshowthatthismodelisfeasibleformodelingradionuclidemigrationinunsaturatedloess.

  • 标签: RADIONUCLIDE MIGRATION the TRACER LAYER LOESS
  • 简介:AbstractPurpose:Secondary displacement represents a frequent complication of conservative treatment of fractures, particularly of the distal radius. The gap space between skin and cast may lead to a certain degree movements and this increased mobility might favor redisplacement. The aim of this study was to develop a new 3D method, to measure the gap space in all 3 geometrical planes, and to validate this new technique in a clinical setting of distal radius fractures.Methods:This study applies 3D imaging to measure the space between plaster and skin as a potential factor of secondary displacement and therefore the failure of conservative treatment. We developed and validated a new methodology to analyze and compare different forearm casts made of plaster of Paris and fiberglass. An unpaired t-test was performed to document differences between the investigated parameters between plaster of Paris and fiberglass casts. The significance level was set at p< 0.05.Results:In a series of 15 cases, we found the width of the gap space to average 4 mm, being slightly inferior on the radial side. Comparing the two different casting materials, plaster of Paris and fiberglass, we found a significantly larger variance of space under casts made of the first material (p=0.39). A roughness analysis showed also a markedly significantly higher irregularity of the undersurface of plaster of Paris as compared with fiberglass.Conclusion:This study allows for a better understanding of the nature of the "gap space" between cast and skin and will contribute to develop and improve new immobilization techniques and materials.

  • 标签: Forearm Wrist casts Radius fractures Conservative treatment Gap space
  • 简介:在这评论,我们在场拓扑的绝缘体(TI)和超导的nanowires和电影的一些最近的实验的一篇摘要。电子电子相互作用(EEI),弱反本地化(WAL)和效果由运输大小在拓扑的绝缘体电影发现了的各向异性的磁致电阻(AMR)被报导。然后,在非超导的nanowires的超导的电影,桥和nanowires和最近效果的运输性质被描述。最后,在拓扑的绝缘体和超导体(SC)之间的相互影响也被讨论。

  • 标签: 电子输运性质 超导薄膜 超导体 绝缘体 拓扑 低维
  • 简介:Thed-dimensionalclassicalHardyspacesHp(Td)areintroducedanditisshownthatthemaximaloperatoroftheRiemannsumsofadistributionisboundedfromHp(Td)toLp(T2)(d/(d+1)

  • 标签: 心气 外簇 日工 火石
  • 简介:Anewmethodformeasuring3-Drigidbodydisplacementsisproposed,inwhichtwoperpendicularbeamsareemittedontotwosensitiveplanesofPSDsleingperpendiculartoeachother.Themethodcanbeusedtomeasure1-Dor2-Ddisplacementswhenrequired.Moreover,theexperimentalresultsarepresented,whichdemonstratethatthenewmethodhashighaccuracy,fastprocessingspeed,highreliability,andeasilybeingrealized.

  • 标签: 显示测量 三维物体 光感测器
  • 简介:Avortexringimpingingonathree-dimensionalbumpisstudiedusinglargeeddysimulationforaReynoldsnumberRe=4×104basedontheinitialtranslationspeedanddiameterofthevortexring.Theeffectsofbumpheightonthevorticalflowphenomenaandtheunderlyingphysicalmechanismsareinvestigated.Basedontheanalysisoftheevolutionofvorticalstructures,twotypicalkindsofvorticalstructures,i.e.,thewrappingvorticesandthehair-pinvortices,areidentifiedandplayanimportantroleintheflowstateevolution.Thecirculationoftheprimaryvortexringreasonablyelucidatessometypicalphasesofflowevolution.Furthermore,themechanismofflowtransitionfromlaminartoturbulentstatehasbeenrevealedbasedonanalysisofturbulentkineticenergy.

  • 标签: 三维数值模拟 涡环 湍流动能 物理机制 大涡模拟 涡流现象