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  • 简介:ApplicationofFoxprotoManagementofArticles¥HuangTuanhuaThedatabasemanagementsystemofFoxpro2.5forwindowsisapopularsoftwareforda...

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  • 简介:在教学,经常会遇到条件不明确的问题,学生常顾此失彼,导致少解或漏解,这需要对不明确条件逐一分析讨论、做出正确的判断,这就是物理分类思想。

  • 标签: 分类思想 物理教学 中学 教学方法
  • 简介:Twodifferentpulsecleaningtechniquesforultra-highcontrastlasersystemsarecomparablyanalysedinthiswork.Thefirstpulsecleaningtechniqueisbasedonnoncollinearfemtosecondoptical-parametricamplification(NOPA)andsecond-harmonicgeneration(SHG)processes.Theotherisbasedoncross-polarizedwave(XPW)generation.Withadoublechirpedpulseamplifier(double-CPA)scheme,althoughtemporalcontrastenhancementinahigh-intensityfemtosecondTi:sapphirechirpedpulseamplification(CPA)lasersystemcanbeachievedbasedonbothofthetechniques,thetwodifferentpulsecleaningtechniquesstillhavetheirownadvantagesandaresuitablefordifferentcontrastenhancementrequirementsofdifferentlasersystems.

  • 标签: PULSE CLEANING TEMPORAL CONTRAST CHIRPED PULSE
  • 简介:Nanocarbonmaterialsplayacriticalroleinthedevelopmentofneworimprovedtechnologiesanddevicesforsustainableproductionanduseofrenewableenergy.Thisperspectivepaperdefinessomeofthetrendsandoutlooksinthisexcitingarea,withtheeffortofevidencingsomeofthepossibilitiesofferedfromthegrowinglevelofknowledge,astestifiedfromtheexponentiallyrisingnumberofpublications,andputtingbasesforamorerationaldesignofthesenanomaterials.Thebasicmembersofthenewcarbonfamilyarefullerene,graphene,andcarbonnanotube.Derivedfromthemarecarbonquantumdots,nanohorn,nanofiber,nanoribbon,nanocapsulate,nanocageandothernanomorphologies.Secondgenerationnanocarbonsarethosewhichhavebeenmodifiedbysurfacefunctionalizationordopingwithheteroatomstocreatespecifictailoredproperties.Thethirdgenerationofnanocarbonsisthenanoarchitecturedsupramolecularhybridsorcompositesofthefirstandsecondgenerationnanocarbons,orwithorganicorinorganicspecies.Theadvantagesofthenewcarbonmaterials,relatingtothefieldofsustainableenergy,arediscussed,evidencingtheuniquepropertiesthattheyofferfordevelopingnextgenerationsolardevicesandenergystoragesolutions.

  • 标签: 纳米碳材料 可再生能源 应用 存储解决方案 可持续生产 太阳能装置
  • 简介:LIGAtechniquehasbeendevelopedsince1993atBSRF,includingthefabricationofLIGAmask,deepX-rayLithography,electroplating,thepouringmoldingandtheapplicationsinsomefields.TheLIGAmaskwithgoldabsorbingstructuresof20μmthicknessand5μmwidthandKaptonmembraneofaround5μmthicnesshasbeensuccessfullfabricatedandappliedtothedeepX-raylithographywiththePMMAstructureof1mmthicknessorobove.thebeamlineformawigglerisusedforthedeepX-raylithographyofLIGAstatiionandisopentootheinstitutesresearchingthedeepX-raylithography.ThenormalprocessofLIGAtechniquewiththeexceptionofmoldinghasbeenestablishedwiththePMMAstructuresof500μmthicknessatBSRF.ThelargestaspectratioofPMMAstructruescanreachabout50withtheheightof500μmandthelateralsiaeof10μm.Thenickelandcopperstructureswiththetheicknessof0.5mmand1mmhavebeenmadebyusingtheelectroplatingtechnique.TheSU8asaresistmaterialofdeepetchlithographywithUVlightisalsodevelopedinthefabricationofLIGAmaskandsomedevicesatBSRF.Electromagneticsteppingmicromotor,haetexchange,accelerator,structuresusedintheEDM(electrodischargemachinging)arebeingdevelopedforthefutureapplications.

  • 标签: BSRF 北京同步辐射装置 X射线 LIGA 微加工 超微步进电机
  • 简介:Thedefinitionsandpurposesofenergysystemsandprocesssystemsarecomparedinthispaperbyconsideringtheroleofenergyinsystemswithemphasisonthedifferencesinthemethodsusedtooptimizetheexergoeconomicbenefitsofbothtypesofsystems.TheprocesssystemexergoeconomicrelationshipprimarilyincludetheestablishmentoftheThree-linkmodelofprocesssystems,thecompositionofobjectivefunctions,andthecorrespondingboundaryconstraintconditionsforoptimization.TheThree-Link-Method(TLM)whichisbasedonexergoeconomics,canbeusedtoeffectivelyoptimizeprocesssystems.TheTLMusedtooptimizeprocesssystemsisoutlinedinthispaper,Someaspectswhichneedfurtherdevelopmentarealsoidentified.

  • 标签: 热能经济 过程系统 优化分析
  • 简介:Nuclearfusionhasenormouspotentialtogreatlyaffectglobalenergyproduction.Thenext-generationtokamakITER,whichisaimedatdemonstratingthefeasibilityofenergyproductionfromfusiononacommercialscale,isunderconstruction.Wallerosion,materialtransport,andfuelretentionareknownfactorsthatshortenthelifetimeofITERduringtokamakoperationandgiverisetosafetyissues.Thesefactors,whichmustbeunderstoodandsolvedearlyintheprocessoffusionreactordesignanddevelopment,areamongthemostimportantconcernsforthecommunityofplasma-wallinteractionresearchers.Todate,lasertechniquesareamongthemostpromisingmethodsthatcansolvetheseopenITERissues,andlaser-inducedbreakdownspectroscopy(LIBS)isanidealcandidateforonlinemonitoringofthewallsofcurrentandnext-generation(suchasITER)fusiondevices.LIBSisawidelyusedtechniqueforvariousapplications.Ithasbeenconsideredrecentlyasapromisingtoolforanalyzingplasma-facingcomponentsinfusiondevicesinsitu.ThisarticlereviewstheexperimentsthathavebeenperformedbymanyresearchgroupstoassessthefeasibilityofLIBSforthispurpose.

  • 标签: LIBS NUCLEAR fusion plasma-facing COMPONENTS
  • 简介:Sportsvideoappealstolargeaudiencesduetoitshighcommercialpotentials.Automaticallyextractingusefulsemanticinformationandgeneratinghighlightsummaryfromsportsvideotofacilitateusers'accessingrequirementsisanimportantproblem,especiallyintheforthcomingbroadbandmobilecommunicationandtheneedforuserstoaccesstheirmultimediainformationofinterestfromanywhereatanytimewiththeirmostconvenientdigitalequipments.Inthispaper,asystemtogeneratehighlightsummariesorientedformobileapplicationsisintroduced,whichincludeshighlightextractionandvideoadaptation.Inthissystem,severalhighlightextractiontechniquesareprovidedforfieldsportsvideoandracketsportsvideobyusingmulti-modalinformation.Toenhanceusers'viewingexperienceandsavebandwidth,3Danimationfromhighlightsegmentisalsogenerated.Asanimportantproceduretomakevideoanalysisresultsuniversallyapplicable,videotranscodingtechniquesareappliedtoadaptthevideoformobilecommunicationenvironmentanduserpreference.Experimentalresultsareencouragingandshowtheadvantageandfeasibilityofthesystemformultimediacontentpersonalization,enhancementandadaptationtomeetdifferentuserpreferenceandnetwork/devicerequirements.

  • 标签: VIDEO analysis VIDEO transcoding HIGHLIGHT summary
  • 简介:Multipaction,causedbythesecondaryelectronemissionphenomenon,hasbeenachallengeinspaceapplicationsduetotheresultingdegradationofsystemperformanceaswellasthereductionintheservicelifeofhighpowercomponents.Inthispaperwereportanovelapproachtorealizeaneffectiveincreaseinthemultipactionthresholdbyemployingmicro-poroussurfaces.Twomicro-porousstructures,i.e.,aregularmicro-porousarrayfabricatedbyphotolithographypatternprocessingandanirregularmicro-porousarrayfabricatedbyadirectchemicaletchingtechnique,areproposedforsuppressingthesecondaryelectronyield(SEY)andmultipactionincomponents,andthebenefitsarevalidatedboththeoreticallyandexperimentally.Thesesurfaceprocessingtechnologiesarecompatiblewiththemetalplatingprocess,andoffersubstantialflexibilityandaccuracyintopologydesign.Thesuppressioneffectisquantifiedforthefirsttimethroughtheproperfittingofthesurfacemorphologyandthecorrespondingsecondaryemissionproperties.Insertionlosseswhenusingthesestructuresdecreasedramaticallycomparedwithregularmillimeter-scalestructuresonhighpowerdielectricwindows.SEYtestsonsamplesshowthatthemaximumyieldofAg-platedsamplesisreducedfrom2.17to1.58fordirectlychemicaletchedsamples.MultipactiontestingofactualC-bandimpedancetransformersshowsthatthedischargethresholdsoftheprocessedcomponentsincreasefrom2100Wto5500Wforphotolithographypatternprocessingand7200Wfordirectchemicaletching,respectively.Insertionlossesincreasefrom0.13dBtoonly0.15dBforbothsurfacetreatmentsinthetransmissionband.Theexperimentalresultsagreewellwiththesimulationresults,whichoffersgreatpotentialinthequantitativeanti-multipactiondesignofhighpowermicrowavecomponentsforspaceapplications.

  • 标签: 高功率微波器件 空间应用 微放电 抑制方法 化学蚀刻技术 次级电子发射
  • 简介:BeamalignmentdependsonCCDreal-timeimageanalysisandprocessing.Inordertoimprovethequalityofthealignment,multiplefiltersareusedinfar-fieldandnear-fieldimageprocessings.Thesemultiplefiltersareconstitutedofanaveragefilterandamedianfilterindifferentconnectionsequences,sothattheycandealwithdifferentkindsofnoise.Toreducetheeffectoftheunknownnonlinearrelationshipbetweenmotorrunningstepsanddeviationpixels,afeasiblemethodologyisofferedtoimprovethisphenomenonandafuzzyalgorithmisappliedtothemotorfeedbackcontrolprocess.Becauseofthefuzzycontrolitisnotnecessarytoestablishanaccuratemathematicalmodel,sotheimpactofthenonlinearrelationshipwillbereduced.

  • 标签: ALIGNMENT FUZZY control IMAGE processing MULTIPLE
  • 简介:为软件开发基于一个新DIY概念,在当有限元素程序生成器(FEPG)提供发展的一个平台,叫的一个软件系统上依附的一种自动产生节目的技术编程序,通过哪个一个科学研究人员能为解决方案以一个更直接、方便的方法提交他的特殊physico数学的问题到系统。为由使用有限元素方法解决流动和热问题,稳定技术和部分步方法被采用克服主要由于统治传送对流引起的数字困难。几个基准问题作为例子在这份报纸被给说明用法和自动程序产生技术的优势,包括在一个盖驱动的洞的流动,在一根圆形的管子的开始的流动,在一个方形的洞的自然传送对流,并且经过圆形的柱体的流动,等等。他们也作为算法的确认被给看。

  • 标签: 传热与流体流动问题 程序生成技术 应用 稳定有限元法