简介:Theusual(1+1)-dimensionalSchwartzBoussinesqequationisextendedtothe(1+1)-dimensionalspace-timesym-metricformandthegeneral(n+1)-dimensionalspace-timesymmetricform.TheseextensionsarePainlevintegrableinthesensethattheypossessthePainlevproperty.Thesinglesolitonsolutionsandtheperiodictravellingwavesolutionsforarbitrarydimensionalspace-timesymmetricformareobtainedbythePainlev-Bcklundtransformation.
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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.
简介:Thefatiguebehaviorofahighstrengthsteel300Minthegigacycleregimewasinvestigated.Fullyreversedtension-compressionfatiguetestsatambienttemperaturewereperformedusinganultrasonicfatiguesystemoperatingat20kHz.Thestaircasetestmethodwasemployedtoobtainaccuratevaluesofthemeanfatiguestrengthcorrespondingtofixednumbersofcyclesupto10~9.Theseresultswerecomparedtothecurvewhichisestimatedbythedatatestedinthemid-longliferegimeonconventionalservohydraulictestmachineat20Hz.Resultsindicatethatthefatiguestrengthdeterminedfromultrasonicfatiguetestingislightlyhigherthanconventionaltestingintherangeof10~6-10~7cycles.Itisobviousthatnucleationsoffracturestendtooccurbelowthesurface,iffractureshappenaftermorethan10~7cycles.AllthefracturedspecimensfailsfrominternalSiO_2inclusionsorsmallercarbidesandcarbideclusters.
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简介:Spreadoffiresmokeintheelevatorshaftofahigh-risebuildingisinfluencedbymanydrivingfacts.Wesimulatesmokespreadingintheelevatorshaft,stairroom,andpre-chamberwithandwithoutdifferentsuppliedpressurizedair.Thesimulationshowsthatsmokemovesveryfastintheelevatorshaft.Whena12floorhigh-risebuildingisinfire,smokecanfilluptheelevatorshaftinlessthan1.5minafterafirestarted,temperatureintheelevatorshaftcanbehigherthan187?Cin5min,andtheconcentrationofCOcanalsoreachahighlevel.Theelevatorshafthasaverylowvisibilityinlessthanabout100s.
简介:BytheaidofanideaoftheweightedENOschemes,someweight-typehigh-resolutiondifferenceschemeswithdifferentordersofaccuracyarepresentedinthispaperbyusingsuitableweightsinsteadoftheminmodfunctionsappearinginvariousTVDschemes.Numericalcomparisonsbetweentheweightedschemesandthenon-weightedschemeshavebeendoneforscalarequation,one-dimensionalEulerequations,two-dimensionalNavier-StokesequationsandparabolizedNavier-Stokesequations.
简介:Heathandlinghasbeenasignificantproblemofthehighpowerfiberlasersystemsastheoutputpowerincreasesrapidly.Claddingpowerstripper(CPS)whichisusedtodealwiththeunwantedopticalpowerandlightisrequiredforhighercoolingability.Sothemethodsofstrippingtheunwantedlightattractedmuchattentionrecently,andthethermaleffectisgiven.However,fewinvestigationsfocusonthedissipationoftheheatconvertedfromtheunwantedlight.Inthispaper,anapproachofactivecoolingforCPSisdemonstrated.ThisisachievedbyusingmicrochannelcoolingtechnologyinheatsinkinginCPStoimprovetheefficiencyofheatexchange.InordertoexplainthemechanismofCPSthefunctionofitandconsistenceofcategoriesoftheunwantedlightaredetailedfirstly.Thenmicrochannelheatsinkingisproposedandverifiedbytheheatexchangetheory.Atlast,thedesignoftheCPSwithmicrochannelheatsinkingisshownandfollowingexperimentisconducted.Thefinaltemperatureofthedevicewith1000WcladdingpowerwasdemonstratedatlasttoverifytheabilityofheatdistributionoftheCPScomponent.ThissuggeststhattheseCPSscanbeusedtostripeathousandofwattsoflightinhighpowerdoublecladdingfiberlasers.
简介:AhighpressureenergydispersiveX-raydiffractionapparatuson3W1Abearmline,atBSRF,isdescribed.Aten-PolespermanentmagneticwigglerprovidedwhiteX-raybeam.Theextremehighpressureupto115GPahasbeenobtainedbyamodifiedMao-Belldiamondanvilcell.Amotorizedloadingsystemwithstrainsensorcanfinelycontrolthepressurechange.Theinsituexperimentalproceduresaredescribed.Someapplicationsarealsopresented.2001ElsevierScienceB.V.Allrightsreserved.
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.
简介:In2014,researchersinthehighenergynuclearphysicsgroupatIMPhavecarriedouttheirresearchworkonhadronphysics.Severalinterestingresultswereobtainedandpublished.Themesonandbaryonexcitedstateshavebeenstudiedinalargenumberofformationandproductionexperiments.Thestudyofmesonresonancesandthesearchforglueballs,hybrids,andmultiquarkstateshaveremainedanactiveandinterestingfieldofhadronphysics,whileforbaryons,theinvestigationofthebaryonspectrumandthebaryoncouplingsfromexperimentaldataarealsothemostimportantissuesinhadronicphysicsandtheyareattractingmuchattention.StudyinghadronresonancesiscrucialtounderstanddeeplytheQCDtheoryatnonperturbativeenergyregion,anditisalsoimportantfornuclearphysicsandparticlephysics.
简介:Waveguidesuperlattices,aspecialtypeofwaveguidearrays,canbedesignedtoachieveverylowcrosstalkatsubmicrometer/subwavelengthpitches.Thetheoreticalframeworkanddesignrationalesforsuchwaveguidesuperlatticeswillbepresentedindepth.Waveguidesidewallroughnesscanhelptodeterthecoherentcouplingbetweenidenticalwaveguidesinnearbysupercells,butitalsoinducesrandomfluctuationoftransmission.Statisticalbehaviorofthetransmissionduetoroughnessinawaveguidesuperlatticeissystematicallytreated.Complextransmissioncharacteristicsduetospectraloscillationandrandomroughnesswillbepresented,andtheirevolutionwiththesuperlatticelengthwillbeanalyzed.
简介:Furtheradvancementofhigh-energypulsedlasersrequiresaparalleldevelopmentofappropriateopticalcomponents.Severaldifferentopticalcomponents,suchasmirrorsandantireflection-coatedwindows,whichareessentialforthedesignofHiLASEhighaveragepowerlasersweretested.Thefollowingpapersummarizesresultsonthemeasurementsoflaser-induceddamagethresholdofsuchcomponents,andclearlyshowstheircapabilitiesandlimitationsforsuchademandingapplication.
简介:LargedistributedsystemssuchasComputational/DataGridsrequirelargeamountsofdatatobeco-locatedwiththecomputingfacilitiesforprocessing.Fromourworkdevelogpinascalabledistributednetworkcache.wehavegainedexperiencewithtechniquesnecessarytoachievehighdatathroughputoverhighbandwidthWideAreaNetworks(WAN).Inthispaper,wediscussseveralhardwareandsoftwaredsigntechniques,andthendescribetheirapplicationtoanimplementationofanenhancedFTPprotocolcalledGridFTP,WedescriberesultsfromtheSupercomputing2000conference.
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.