简介:Higher-bandself-trappingandoscillation(rotation)ofnonlinearquadruplebeamsintwo-dimensional(2D)squarephotoniclatticesarenumericallydemonstrated.Underappropriateconditionsofnonlinearity,aquadruple-likebeamcanself-trapintolocalizedmodesthatresideinthesecondBraggreflectiongapthroughsingle-siteexcitation.Bychangingtheinitialorientationoftheincidentquadruplebeamrelatedtothelattices,periodicoscillationsofthelocalizedquadruplemodemaybeobtained.Thelocalizedquadruplestatebecomesarotatingdoublychargedopticalvortex(DCV)duringrotationandshouldundergocharge-flippingwhentherotatingdirectionisreversed.
简介:与传统宽波段成像系统相比,多光谱成像系统在性能表征、测试方法等方面有较大不同,而相关研究较为欠缺。因此,需要重点研究多光谱成像系统的综合性能评估方法。解决了目标光谱反射率等效控制、宽波段光谱维度的带内细分和标准靶标辐亮度调节等关键技术,设计了基于AOTF的多光谱成像系统二维鉴别率阈值测试平台及测试方法。在理论分析基础上,实际搭建了基于AOTF的可见光多光谱成像系统,叙述了系统标定方法和测试步骤,并基于所述方法在实验室条件下完成了系统空间分辨率、目标光谱反射率与对比度阈值的三维曲面测试实验。测试结果标明,所提出的方法可较好地反映不同谱段响应特性的差异,实现对多光谱成像系统的性能表征。基于该方法,可综合评估系统光谱分辨率、空间分辨率、灵敏度、对比度等性能指标,从而为多光谱成像系统性能的定量表征提供技术支持。
简介:九年前推出的D90是尼康的经典机型,也是那个年代最值得购买的单反相机之一.它的摄像功能虽然不完善,但在那时5000元级别的单反里也是独一份.当然,今天要聊的D90可不是前段时间天天被传着要破产的尼康,而是上汽大通新推出的SUV.这款车型似乎也有独一份的噱头,那它会不会在九年后也能成为老司机们的谈资呢?
简介:由消费者定价的C2B概念被眼前这台轴距近3米的全尺寸SUV拉开了序幕。3-8座内部布局、18英寸~21英寸轮毂、五种进气格栅可选。单凭这些可选配置,就有理由在自主品牌的汽车发展史上留下重要一笔。
简介:Theeffectofλ/2SiO2overcoatonthelaserdamagecharacteristicsofHfO2/SiO2high-reflector(HR)coatingsisinvestigatedwith1-on-1andN-on-1laserdamagetestmethods.Thelaserdamagesurfaceof1-on-1isanalyzedbyastepanalyzer.ThesurfacemorphologiesshowthatlaserdamagemakesthecoatingdamagedareaprotrudentandroughforHRcoatingwithoutλ/2silicaovercoat,butconcaveandsmoothforHRcoatingwithλ/2silicaovercoat.Theresultof10-on-1multi-pulseirradiationonthesamepointofthecoatingshowsthatthereisanenergydensitystageonthedamagecurve.Ifthelaserenergydensityiswithintherangeofthestage,HfO2/SiO2HRcoatingswithλ/2silicaovercoatwillnotbedamagedmorethan2timesformulti-shots,andthesurfacedamagesareveryslightsothatthereisnoimpactonthecoatingperformance.Anotherinterestingresultisthattheenergydensitystageextendsfromthedamagethresholdtothepointofabout3timesofthreshold,whichissimilartotheeffectofthelaserconditiononcoating.
简介:Thereappeartobethreeprincipleforcesdrivingthefutureofnewdrugdevelopment:under-standingthegenome-transcrip-tome-protemecorrelations,under-standingandmappingproteinposttrans-lationalmodification(PTM)pathways,andintegrationofmassspectrometry(MS)techniquesintoroutineproteinidentificationandcharacterization.
简介:简要及综合性地叙述了特瑞堡密封系统有限公司拥有知识产权的佐康?热塑性弹性体密封材料;D型格来?圈的结构及推荐应用的细分市场。