简介:FLASHatDESY,Hamburg,Germanyisthefirstfree-electronlaser(FEL)operatingintheextremeultraviolet(EUV)andsoftx-raywavelengthrange.FLASHisauserfacilityprovidingfemtosecondshortpulseswithanunprecedentedpeakandaveragebrilliance,openingnewscientificopportunitiesinmanydisciplines.Thefirstcallforuserexperimentshasbeenlaunchedin2005.TheFLASHlinearacceleratorisbasedonTESLAsuperconductingtechnology,providingseveralthousandsofphotonpulsespersecondtouserexperiments.Probingfemtosecond-scaledynamicsinatomicandmolecularreactionsusing,forinstance,acombinationofx-rayandopticalpulsesinapumpandprobearrangement,aswellassingle-shotdiffractionimagingofbiologicalobjectsandmolecules,aretypicalexperimentsperformedatthefacility.WegiveanoverviewoftheFLASHfacility,anddescribethebasicprinciplesoftheaccelerator.Recently,FLASHhasbeenextendedbyasecondundulatorbeamline(FLASH2)operatedinparalleltothefirstbeamline,extendingthecapacityofthefacilitybyafactoroftwo.
简介:摘要本文从网络教学平台的定义入手,简述了当前信息技术应用在教学过程中的问题,然后从两个方面论述了网络教学平台对FLASH课程教与学的促进作用,并结合自己对网络教学平台在FLASH课程中的应用,综合得出了网络教学平台在FLASH课程应用中的高品质效果。
简介:Understandingtheradiationmodelofaflashlampisessentialforthereflectordesignofalaseramplifier.Reflectordesignofteninvolvesseveralsimplifyingassumptions,likeapointorLambertiansource;eitheroftheseassumptionsmayleadtosignificanterrorsintheoutputdistribution.Inpractice,sourcenon-idealitiesusuallyresultinsacrificingtheamplifier’sgaincoefficient.Weproposeanoveltesttechniqueforattainingthexenonflashlampabsolutespectralintensityatvariousanglesofview,andthenaccuratelypredictradiationdistributionsandgeneratethereflectorshape.Itisshownthatduetotheabsorptionofemittedradiationbythelampitself,thebehavioroftheradiationmodelatvariouswavelengthsisdifferent.Numericalresultsofxenonplasmaabsorptioncoefficientwerecomparedwiththemeasureddata.Areasonableagreementwasobtainedfortheabsorptioncoefficientparameters.Thus,thisworkprovidesausefulanalyticaltoolfortheengineeringdesignoflaseramplifierreflectorsusingxenonflashlampsaspumps.
简介:摘要ADI公司的TS系列DSP在工业产品中得到了广泛应用,在实际产品中,对于多片DSP组成的并行处理系统多采用总线互联的紧耦合工作方式。本文介绍了一种单个FLASH芯片加载多个DSP的引导方法,相比较之前常用的LINK链路口顺序加载方法具有编译简单,加载方便,易于修改的特点。