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116 个结果
  • 简介:用photonic晶体(PC),轻射出的二极管(LEDs)的抽取效率能被photonic乐队差距(PBG)和栅栏衍射的效果极大地提高。二个理论方法也被讨论。同时,我们证明LEDs能由作为衍射栅栏采用photonic水晶完成高抽取效率。有圆柱的单位房间的方形的格子的PC被制作在轧了带的基于陷阱的蓝色的层。我们在场PC-LED的抽取效率的理论讨论,它依靠有效中等理论和传播矩阵方法调查格子常数的效果。当格子常数是270nm时,结果证明高效LEDs的抽取效率能完成61.8%。

  • 标签: 提取效率 光子晶体 LED 蓝色发光二极管 有效介质理论 光栅衍射
  • 简介:VO2thinfilmswithgoodswitchingpropertieswerepreparedbycontrollingtheannealingtimeandtheannealingtemperatureinavacuumsystem.Thestructural,opticalandelectricalpropertiesofthesampleswerecharacterizedbyusingXRD、XPS、UV-VISandelectricalmeasurements.TheswitchingparametersofVO2thinfilmwereinvestigatedtoo.TheresultsindicatethatbeforeandafterphasetransitiontheresistanceofVO2thinfilmschangesaboutthreeordersofmagnitude,thevariationoffilmtransmittanceof40%hasbeencarriedoutwiththeabsorptivityswitchingvelocityofabout0.2607/minat900nm.Thestructuralpropertyofsampleshasbeenimprovedbutthephase-transitionpropertieshavebeendecreasedbyincreasingtheannealingtimeandannealingtemperature.ThevalenceofVionsandthestructureofsampleshavegreateffectonphasetransitionpropertiesofVO2thinfilms.Discussionontheeffectsofannealingtimeandannealingtemperatureonthephase-transitiontemperatureandhysteresiswidthshowsthatthebestreasonableannealingtimeandannealingtemperaturecanbeachieved.

  • 标签: 氧化钒薄膜 相变 薄膜结构
  • 简介:Analternativemethodisproposedinthisletterfordescribingthearbitraryshapeandsizeforgranulesin2Dimage.Afterimagebinarization,theedgepointsoncontouraredetected,bywhichthecentroidoftheshapeinquestionissoughtusingthemomentcalculation.UsingPrincipalComponentAnalysis(PCA),themajorandminordiametersarecomputed.Basedonthesignaturecurve-fitting,thefirst-orderderivativeistakensoastoseekallthecharacteristicvertices.Byconnectingtheverticesfound,thesimplifiedpolygonisformedandutilizedforshapeandsizedescriptivepurposes.Thedevelopedalgorithmisrunontwogivenrealparticleimages,andtheexecutionresultsindicatethatthecomputedparameterscantechnicallywelldescribetheshapeandsizefortheoriginalparticles,beingabletoprovideaready-to-usedatabaseformachinevisionsystemtoperformrelateddataprocessingtasks.

  • 标签: 任意形状 二维图像 颗粒 机器视觉系统 直径计算 粒子图像
  • 简介:SprintNextel与WaltDisney旗下ABC集团在重新部署频谱使用问题上达成统一意见,协议中允许Sprint在超过2千兆赫的波段提供商业移动无线服务。Sprint将支付ABC重新部署网络所需的费用,其中包括了使用在新频率中设备资金。基于FCC美国联邦通信委员会的规定,持有2千兆赫广播辅助服务的许可人,例如ABC,必须在2007年9月前完成频率重新部署的工作。

  • 标签: SPRINT 移动服务 频谱 美国联邦通信委员会 ABC 使用问题
  • 简介:Theletterproposesathree-layermanageablemediadistributionnetworksystemarchi-tecturecalledMSPnet,whichisbasedonSessionInitiationProtocol[1]andPeertoPeer(SIPP2P)technology.MSPnetperformsapplication-levelstructuredDHTroutingandresourcelocationamongdomainsandunstructuredonesindomain.Exceptformediadistribution,itcanbeusedtosupportavarietyofP2Papplications,includingvideobroadcasting,videoondemand,VoIP,etc.MSPnetiscomposedofthreelayers,namely,thesignalcontrollayer,themanagementlayer,andthemediatransportationlayer.TheMSPnetprototypeconsistsoftheSIPserver,themanagementserver,themediaserver,andthenodeUserAgent(UA).Resultsfromaprototypeexperimentinalarge-scaleInternetenvironmentshowthatMSPnetisfeasible,scalableandmanageable.

  • 标签: 点对点技术 计算机技术 网络 设计方案
  • 简介:AnewcompactopticalFanofiltersuitableforbiologicalsensingisproposed,whichpatternsphotoncrystalinsinglecrystallinesiliconnanomembranes(SiNMs)andtransferringontotransparentglasssubstrates.Theeffectsofairholesizeandsiliconthicknessonthetransmissioncharacteristicsofnewfilterarenumericallyinvestigatedbyusingthree-dimensionalfinite-differencetime-domain(FDTD)technique,thespectralresponseisalsostudiedbyback-fillingbioliquid.Theresultsshowthatthedipwavelengthwillshifttowardlongerwavelengthbyeitherreducingairholeradiusorfillingbio-liquid.Thenumberofdipswillincreasewiththeincreaseofsiliconthickness.Thesizeofproposedfiltercanbelessthan1mm2.

  • 标签: 二维光子晶体 生物传感 玻璃基板 过滤器 三维有限差分 光学遥感器
  • 简介:1O月19日.第2届亚洲印刷奖颁奖大会在新加坡RitzCarltonHotel举行。作为此次亚洲印刷奖的重要赞助商之一。柯达保丽光印艺集团通过此次大会。又在提升亚洲印刷和包装质量的标准中发挥了重要作用。

  • 标签: 第2届 印刷 亚洲 柯达保丽光印艺集团 包装质量 新加坡
  • 简介:文章主要阐述了I^2C总线控制音响电路的工作原理,探讨I^2C总线控制音响电路的测试方法,介绍了在A370测试系统上使用高速数字模块(M621)对I^2C总线控制的编码方法以及配合M625和M601模拟模块对输出音频信号进行测试的软件开发。

  • 标签: I^2C总线 音响电路 测试系统
  • 简介:Videoobjectextractionisakeytechnologyincontent-basedvideocoding.AnovelvideoobjectextractingalgorithmbytwoDimensional(2-D)mesh-basedmotionanalysisisproposedinthispaper.Firstly,a2-Dmeshfittingtheoriginalframeimageisobtainedviafeaturedetectionalgorithm.Then,higherorderstatisticsmotionanalysisisappliedonthe2-Dmeshrepresentationtogetaninitialmotiondetectionmask.Afterpost-processing,thefinalsegmentingmaskisquicklyobtained.Andhencethevideoobjectiseffectivelyextracted.Experimentalresultsshowthattheproposedalgorithmcombinesthemeritsofmesh-basedsegmentingalgorithmsandpixel-basedsegmentingalgorithms,andherebyachievessatisfactorysubjectiveandobjectiveperformancewhiledramaticallyincreasingthesegmentingspeed.

  • 标签: 视频 对象分析 2-D 网孔 统计学
  • 简介:TheproblemsofcharacteristicpolynomialassignmentinFomasini-Marchesini(F-M)modelⅡof2-Dsystemsareinvestigated.Thecorrespondingclosed-loopsystemsdescribedbyF-MmodelIIareobtainedviathestatefeedback.Usingthealgebraicgeometrymethod,thecharacteristicpolynomialassignmentinthedosed-loopsystemsisdiscussed.Intermsofthetheoryofalgebraicgeometry,theproblemofcharacteristicpolynomialassignmentistransferredtotheonewhetherarationalmappingisonto.SufficientconditionsforalmostarbitraryassignmentcoefficientsofcharacteristicpolynomialinF-MmodelⅡof2-Dsystemsviastatefeedbackarederived,andtheyareavailableformulti-inputcases.Italsohasbeenshownthatthismethodcanbeappliedtoassignthecharacteristicpolynomialwithoutputfeedback.Thesufficientconditionsforalmostarbitraryassignmentcoefficientsofcharacteristicpolynomialofmulti-input2-DsystemsdescribedbyF-MmodelⅡwithoutputfeedbackareestablished.

  • 标签: F-M模型 特征多项式 代数几何 二维线性系统
  • 简介:<正>意法半导体、飞利浦和摩托罗拉等公司合作组成的Crolles2联盟日前在法国成立联合研发中心,致力于12英寸晶圆的新一代半导体制造技术。该联合研发中心将在未来的5年中致力于把目前90纳米CMOS工艺提升到32纳米,同时,中心内的一条12英寸晶圆生产线已正式启动。Crolles2联盟是全球几大公司在

  • 标签: Crolles2 意法半导体 半导体制造 微电子领域
  • 简介:ThekeyprobleminunstructuredP2Psystemishowtocontrol'Flood'.Somestudiesfocusonconstructingmoreefficienttopologywhileothersfocusonbetterqueryalgorithms.ThispaperpresentsHICUS(HierarchicalInterest-drivenCommunity-basedUnstructuredSystem)motivatedbyabasicthought-whethertheresourcescorrelatewithtopologydistinguishesstructuredandunstruc-turedP2Pessentially.Byintroducinghierarchical'interest',HICUSorganizesaquasi-structuredtopologythroughapuredistributedway,andprovidesanewplatformforqueryalgorithms.Westudytheprocedureandperformanceoftopologyorganization,andthesimulationsshowthatHICUSformsasmall-worldwhichcansignificantlyimprovetheroutingefficiency.

  • 标签: P2P系统 非结构化 拓扑结构 分布方式 仿真结果 执行情况
  • 简介:AnewschemebasedonSOA-MZIforall-optical2Rregenerationisproposed.Thecharacteristicsofgainandswitchingwindowofthisdeviceareinvestigatedindetail.Numericalsimulationresultsindicatethatthenonlineargaincompression,thetimedelaybetweentheinputopticalsignalandthewidthoftheopticalpulseareessentialparametersforagoodperformanceofall-optical2Rregeneration.

  • 标签: 半导体光放大器 SOA 光开关 MACH-ZEHNDER干涉仪 波分复用 光网络
  • 简介:<正>互联网时代,金融业作为传统行业中最封闭、坚硬的一块,正被新闯入者逐渐打破。以支付宝为代表的第三方支付在如履薄冰多年后,终于在最近两年里,陆续拿到期盼已久的牌照。这支互联网金融的先锋大军,早已从PC、移动设备端蚕食银行业的支付业务。而作为互联网金融的新贵,P2P网贷心怀远大,其意图染指的是银行业最重

  • 标签: 第三方支付 P2P 支付宝 支付业务 借款人 信用卡套现
  • 简介:ReactiveionetchingcharacteristicsofGaAs,GaSb,InPandInAsusingCl2/Arplasmahavebeeninvestigated,itisthat,etchingratesandetchingprofilesasfunctionsofetchingtime,gasflowratioandRFpower.Etchratesofabove0.45μm/rinand1.2μm/rinhavebeenobtainedinetchingofGaAsandGaSbrespectively,whileveryslowetchrates(<40nm/rin)wereobservedinetchingofIn-containingmaterials,whichwerelinearlyincreasedwiththeappliedRFpower.EtchedsurfaceshaveremainedsmoothoverawiderangeofplasmaconditionsintheetchingofGaAs,InPandInAs,however,werepartlyblackenedinetchingofGaSbduetoaroughappearance.

  • 标签: 反应离子蚀刻 GAAS GASB INP INAS 等离子体