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500 个结果
  • 简介:Theusual(1+1)-dimensionalSchwartzBoussinesqequationisextendedtothe(1+1)-dimensionalspace-timesym-metricformandthegeneral(n+1)-dimensionalspace-timesymmetricform.TheseextensionsarePainlevintegrableinthesensethattheypossessthePainlevproperty.Thesinglesolitonsolutionsandtheperiodictravellingwavesolutionsforarbitrarydimensionalspace-timesymmetricformareobtainedbythePainlev-Bcklundtransformation.

  • 标签: HIGH-DIMENSIONAL INTEGRABLE model Schwartz BOUSSINESQ EQUATION
  • 简介:AfterhavingevaluatedvariousH.323productsforthesetwoyears,KEKandJapaneseHENPcommunitystartedtomovefromISDN(H.320)-basedvideoconferencingenvironmentintoIP(H.323)-basedone.PrimaryreasonforthemoveistocutdowntheeverincreasingISDNcommunicationcost.AtthesametimetheH.323canofferusmorepowerfulcollaborativeenvironment.InordertomakeKEKtobeacenterfortheH.323-basedcollaborativeenvironmentinJapan,PictureTel'sLIVEGATEWAYasaH.320/H.323gateway,whichisessentialforthesmoothtransition,CiscoIP/VA3510asaH.323/MCU,andCisco2610asagatekeeperwereinstalledatKEKinMarch2001,Andthetransitionstarted.Inthispaper,we'lldescribethecollaborativeenvironmentwhichouruserscanhave,togetherwithitsoperationalresults.

  • 标签: H.323 高能物理 核物理 实验
  • 简介:Thefatiguebehaviorofahighstrengthsteel300Minthegigacycleregimewasinvestigated.Fullyreversedtension-compressionfatiguetestsatambienttemperaturewereperformedusinganultrasonicfatiguesystemoperatingat20kHz.Thestaircasetestmethodwasemployedtoobtainaccuratevaluesofthemeanfatiguestrengthcorrespondingtofixednumbersofcyclesupto10~9.Theseresultswerecomparedtothecurvewhichisestimatedbythedatatestedinthemid-longliferegimeonconventionalservohydraulictestmachineat20Hz.Resultsindicatethatthefatiguestrengthdeterminedfromultrasonicfatiguetestingislightlyhigherthanconventionaltestingintherangeof10~6-10~7cycles.Itisobviousthatnucleationsoffracturestendtooccurbelowthesurface,iffractureshappenaftermorethan10~7cycles.AllthefracturedspecimensfailsfrominternalSiO_2inclusionsorsmallercarbidesandcarbideclusters.

  • 标签: 疲劳行为 寿命评估 高强度钢 政权 压缩疲劳试验 超声疲劳试验
  • 简介:与自我纺纱关联和微分操作符技术基于有效地的理论,有简单立方的、以身体为中心的立方,以及以脸为中心的格子上的二轴的水晶地的spin-2系统的物理性质被学习了。Theinfluences外部纵磁性在磁化,内部精力,特定的热,和危险性上删除详细被讨论了。处于扎根的状态的磁化看由二轴的横向的水晶领域生产的量效果的现象被发现了。

  • 标签: 二轴晶体场 磁学性质 量子效应 有效场理论 微分算子 各向异性晶体场
  • 简介:Spreadoffiresmokeintheelevatorshaftofahigh-risebuildingisinfluencedbymanydrivingfacts.Wesimulatesmokespreadingintheelevatorshaft,stairroom,andpre-chamberwithandwithoutdifferentsuppliedpressurizedair.Thesimulationshowsthatsmokemovesveryfastintheelevatorshaft.Whena12floorhigh-risebuildingisinfire,smokecanfilluptheelevatorshaftinlessthan1.5minafterafirestarted,temperatureintheelevatorshaftcanbehigherthan187?Cin5min,andtheconcentrationofCOcanalsoreachahighlevel.Theelevatorshafthasaverylowvisibilityinlessthanabout100s.

  • 标签: 高层建筑火灾 火灾烟雾 电梯井 模拟 烟气蔓延 空气传播
  • 简介:BytheaidofanideaoftheweightedENOschemes,someweight-typehigh-resolutiondifferenceschemeswithdifferentordersofaccuracyarepresentedinthispaperbyusingsuitableweightsinsteadoftheminmodfunctionsappearinginvariousTVDschemes.Numericalcomparisonsbetweentheweightedschemesandthenon-weightedschemeshavebeendoneforscalarequation,one-dimensionalEulerequations,two-dimensionalNavier-StokesequationsandparabolizedNavier-Stokesequations.

  • 标签: TVD SCHEMES ENO SCHEMES WENO SCHEMES
  • 简介:Heathandlinghasbeenasignificantproblemofthehighpowerfiberlasersystemsastheoutputpowerincreasesrapidly.Claddingpowerstripper(CPS)whichisusedtodealwiththeunwantedopticalpowerandlightisrequiredforhighercoolingability.Sothemethodsofstrippingtheunwantedlightattractedmuchattentionrecently,andthethermaleffectisgiven.However,fewinvestigationsfocusonthedissipationoftheheatconvertedfromtheunwantedlight.Inthispaper,anapproachofactivecoolingforCPSisdemonstrated.ThisisachievedbyusingmicrochannelcoolingtechnologyinheatsinkinginCPStoimprovetheefficiencyofheatexchange.InordertoexplainthemechanismofCPSthefunctionofitandconsistenceofcategoriesoftheunwantedlightaredetailedfirstly.Thenmicrochannelheatsinkingisproposedandverifiedbytheheatexchangetheory.Atlast,thedesignoftheCPSwithmicrochannelheatsinkingisshownandfollowingexperimentisconducted.Thefinaltemperatureofthedevicewith1000WcladdingpowerwasdemonstratedatlasttoverifytheabilityofheatdistributionoftheCPScomponent.ThissuggeststhattheseCPSscanbeusedtostripeathousandofwattsoflightinhighpowerdoublecladdingfiberlasers.

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  • 简介:AhighpressureenergydispersiveX-raydiffractionapparatuson3W1Abearmline,atBSRF,isdescribed.Aten-PolespermanentmagneticwigglerprovidedwhiteX-raybeam.Theextremehighpressureupto115GPahasbeenobtainedbyamodifiedMao-Belldiamondanvilcell.Amotorizedloadingsystemwithstrainsensorcanfinelycontrolthepressurechange.Theinsituexperimentalproceduresaredescribed.Someapplicationsarealsopresented.2001ElsevierScienceB.V.Allrightsreserved.

  • 标签: BSRF 北京同步辐射装置 X射线衍射 高压 发光性质 EDXD
  • 简介:Thereareseveralpetawatt-scalelaserfacilitiesaroundtheworldandthefidelityofthepulsestotargetiscriticalinachievingthehighestfocusedintensitiesandthehighestpossiblecontrast.TheUnitedKingdomhasthreesuchlaserfacilitieswhicharecurrentlyopenforaccesstotheacademiccommunity:OrionatAWE,AldermastonandVulcan&Astra-GeminiattheCentralLaserFacility(CLF),STFC(ScienceandTechnologyFacilitiesCouncil)RutherfordAppletonLaboratory(RAL).Thesefacilitiesrepresentthetwomainclassesofpetawattfacilities:themixedOPCPA/Nd:glasshigh-energysystemsofOrionandVulcanandtheultra-short-pulseTi:SapphiresystemofAstraGemini.Manyofthetechniquesusedtoenhanceandcontrolthepulsegenerationanddeliverytotargethavebeenpioneeredonthesefacilities.Inthispaper,wepresentthesystemdesignswhichmakethispossibleanddiscussthecontrastenhancementschemesthathavebeenimplemented.

  • 标签: PETAWATT laser CONTRAST WAVEFRONT correction plasma
  • 简介:In2014,researchersinthehighenergynuclearphysicsgroupatIMPhavecarriedouttheirresearchworkonhadronphysics.Severalinterestingresultswereobtainedandpublished.Themesonandbaryonexcitedstateshavebeenstudiedinalargenumberofformationandproductionexperiments.Thestudyofmesonresonancesandthesearchforglueballs,hybrids,andmultiquarkstateshaveremainedanactiveandinterestingfieldofhadronphysics,whileforbaryons,theinvestigationofthebaryonspectrumandthebaryoncouplingsfromexperimentaldataarealsothemostimportantissuesinhadronicphysicsandtheyareattractingmuchattention.StudyinghadronresonancesiscrucialtounderstanddeeplytheQCDtheoryatnonperturbativeenergyregion,anditisalsoimportantfornuclearphysicsandparticlephysics.

  • 标签: NUCLEON PHYSICS GROUP
  • 简介:Waveguidesuperlattices,aspecialtypeofwaveguidearrays,canbedesignedtoachieveverylowcrosstalkatsubmicrometer/subwavelengthpitches.Thetheoreticalframeworkanddesignrationalesforsuchwaveguidesuperlatticeswillbepresentedindepth.Waveguidesidewallroughnesscanhelptodeterthecoherentcouplingbetweenidenticalwaveguidesinnearbysupercells,butitalsoinducesrandomfluctuationoftransmission.Statisticalbehaviorofthetransmissionduetoroughnessinawaveguidesuperlatticeissystematicallytreated.Complextransmissioncharacteristicsduetospectraloscillationandrandomroughnesswillbepresented,andtheirevolutionwiththesuperlatticelengthwillbeanalyzed.

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  • 简介:Furtheradvancementofhigh-energypulsedlasersrequiresaparalleldevelopmentofappropriateopticalcomponents.Severaldifferentopticalcomponents,suchasmirrorsandantireflection-coatedwindows,whichareessentialforthedesignofHiLASEhighaveragepowerlasersweretested.Thefollowingpapersummarizesresultsonthemeasurementsoflaser-induceddamagethresholdofsuchcomponents,andclearlyshowstheircapabilitiesandlimitationsforsuchademandingapplication.

  • 标签: DIODE-PUMPED SOLID-STATE laser and applications LASER-INDUCED
  • 简介:LargedistributedsystemssuchasComputational/DataGridsrequirelargeamountsofdatatobeco-locatedwiththecomputingfacilitiesforprocessing.Fromourworkdevelogpinascalabledistributednetworkcache.wehavegainedexperiencewithtechniquesnecessarytoachievehighdatathroughputoverhighbandwidthWideAreaNetworks(WAN).Inthispaper,wediscussseveralhardwareandsoftwaredsigntechniques,andthendescribetheirapplicationtoanimplementationofanenhancedFTPprotocolcalledGridFTP,WedescriberesultsfromtheSupercomputing2000conference.

  • 标签: 广域网 高带宽数据传输 分布并行存储系统
  • 简介:Inrecentyears,developmentofhigh-performancesupercapacitorelectrodematerialshasstimulatedagreatdealofscientificresearch.Theelectrochemicalperformanceofasupercapacitorstronglydependsonitsmaterialstructures.Herein,wereportasimplestrategyforhigh-performancesupercapacitorsbybuildingpseudocapacitiveCuSnanosphereswithnanoporousstructures,nanosizedwalls(<10nm)andrelativelylargespecificsurfaceareaof65m~2/g.Thiselectrodedemonstratesexcellentelectrochemicalperformanceincludingamaximumspecificcapacitanceof814F/gat1A/g,significantratecapabilityof42%capacitanceretentionatanultrafastrateof50A/g,andoutstandinglong-termcyclingstabilityatvariouscurrentdensities.Theremarkableelectrochemicalperformanceofas-preparednanoporousCuSnanosphereselectrodehasbeenattributedtoitsuniquestructuresthatplaysakeyroleinprovidingshortionandelectrondiffusionpathways,facilitatediontransportandmoreactivesitesforelectrochemicalreactions.Thisworkshedsanewlightonthemetalsulfidesdesignphilosophy,anddemonstratesthatnanoporousCuSnanosphereselectrodeisapromisingcandidateforapplicationinhigh-performancesupercapacitors.

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