简介:ThenewH.264videocodingstandardachievessignificantlyhighercompressionperformancethanMPEG-2.AstheMPEG-2ispopularindigitalTV,DVD,etc.,bandwidthormemoryspacecanbesavedbytranscodingthosestreamsintoH.264intheseapplications.Unfortunately,thehugecomplexitykeepstranscodingfrombeingwidelyusedinpracticalapplications.Thispaperproposesanefficienttranscodingarchitecturewithasmartdownscalingdecoderandafastmodedecisionalgorithm.Usingtheproposedarchitecture,hugebufferingmemoryspaceissavedandthetranscodingcomplexityisreduced.Performanceoftheproposedfastmodedecisionalgorithmisvalidatedbyexperiments.
简介:ThispaperproposesanadaptivejointsourceandchannelcodingschemeforH.264videomulticastoverwirelessLANwhichtakesintoaccounttheusertopologychangesandvaryingchannelconditionsofmultipleusers,anddynamicallyallocatesavailablebandwidthbetweensourcecodingandchannelcoding,withthegoaltooptimizetheoverallsystemperformance.Inparticular,sourceresilienceanderrorcorrectionareconsideredjointlyintheschemetoachievetheoptimalperformance.Andachannelestimationalgorithmbasedontheaveragepacketlossrateandthevarianceofpacketlossrateisproposedalso.Twooverallperformancecriteriaforvideomulticastareinvestigatedandexperimentalresultsarepresentedtoshowtheimprovementobtainedbythescheme.
简介:In2010,theBESCollaboration[1]foundaclearenhancementintheK0K0massdistributionintheJ=ψ!ηK0K0decay.SuchanenhancementisusuallyasignatureofanL=0resonancearoundthreshold,whichinthiscasewouldcorrespondstoanh1statewithquantumnumbersIG(JPC)=0??(1+??).Thish1statewaspredictedbytheChiralUnitarytheoryintheKKinteraction.Becauseoftheconversationlaw,thisstatecanonlydecaytoK0K0channel,andcanbestudiedefficientlyintheJ=ψ!ηK0K0decay.
简介:ConstructingareasonablereactionkineticmodelforCr-containingwasteincinerationisofhighsignificancetostudytheeffectofvariousfactors,suchastemperature,Cl,onitshexavalentchromiumcompounds.Inthispaper,aprimaryCr/H/Air/ClreactionkineticmodelisbuiltandstudiedbyGaussian03codewithquantumchemistrytheory.Numericalresultsshowthattherearetwooverallreactionsinthemodel,eachofthetwooverallreactionsconsistsoftheirrespectivetwoelementaryreactions.Sothetwooverallreactionsshouldbeomittedfromthemodel.Instead,thefourelementaryreactionsshouldbeaddedintheCr/H/Air/Clreactionkineticmodel.Theactivationenergiesofthefourelementaryreactionsarealsocalculated.
简介:Experimentalresultsarepresentedforsuperfluid(HeⅡ)flowthroughporousplugliquid-vaporphaseseparators.Testshavebeenperformedonsevenporousplugswithdifferentthicknessesordifferentpermeabilities.Thetemperaturewasmeasuredfrom1.5Kto1.9K.Twoflowregionswereobservedinsmallandlargepressureandtemperaturedifferencesregionsrespectively.Theexperimentaldataarecomparedwiththeoreticalpredictions.Theperformanceandapplicabilityofthebasictheoryarediscussed.Hysteresisoftheflowrateisalsoobservedanddiscussed.
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:Thedefectchangesin6H-SiCafterannealingand10MeVelectronirradiationhavebeenstudiedbyusingavariable-energypositronbeam.Itwasfoundthatafterannealing,thedefectconcentrationinn-type6H-SiCdecreasedduetorecombinationwithinterstitials.Whenthesamplewasannealedat1400℃for30mininvacuum,a20-nmthicknessSilayerwasfoundonthetopoftheSiCsubstrate,thisisadirectproofoftheSiatomsdiffusingtosurfacewhenannealedathightemperaturestages.After10MeVelectronirradiation,forn-type6H-SiC,theSparameterincreasedfrom0.4739to0.4822,andtherelativepositron-trappingratewasabout27.878timesoftheoriginsample,thisshowsthattherearesomedefectscreatedinn-type6H-SiC.Forp-type6H-SiC,itisveryunclear,thismaybebecauseoftheoppositechargeofvacancydefects.
简介:LinuxbasednetworkedPCsclustersarereplacingboththeVMEnonuniformdirectmemoryaccesssystemsandSMPsharedmemorysystemsusedpreviouslyfortheonlineeventfilteringandreconstrucion.ToallowanoptimaluseofthedistributedresourcesofPCclustersanopensoftwareframeworkispresentlybeingdevelopedbasedonadataflowparadigmforeventprocessing.Thisframeworkallowsforthedistributionofthedataofphysicseventsandassociatedcalibrationdatatomultiplecomputersfrommultipleinputsourcesforprocessingandthesubsequentcollectionoftheprocessedeventsatmultipleoutputs.Thebasisofthesystemistheeventrepository,basicallyafirst-infirst-outeventstorewhichmaybereadandwritteninamannersimilartosequentialfileaccess.Eventsarestoredinandtransferredbetweenrepositoriesassuitablylargesequencestoenablehighthroughput.Multiplereaderscanreadsimultaneouslyfromasinglerepositorytoreceiveeventsequencesandmultiplewriterscaninserteventsequencestoarepository,Hencerepositoriesareusedforeventdistributionandcollection.Tosupportsynchronisationoftheeventfolowtherepositoryimplementsbaaiers.Abarriermustbewrittenbyallthewritersofarepositorybeforeanyreadercanreadthebarrier,Areadermustreadabarrierbeforeitmayreceivedatafrombehindit.Onlyafterallreadershavereadthebarrieristhebarrieremovedfromtherepository.Abarriermayalsohaveattacheddata,Inthiswaycalibrationdatacanbedistributedtoallproessuingunits.Therepositoriesareimplementedasmulti-threadedCORBAobjectsinC++andCORMAisusedforalldatatransfers,JobsetupscriptsarewritteninpythonandinteractivestatusandhistogramdisplayisprovidedbyaJavaprogram.JobsrununderthePBSbatchsystemprovidingshareduseofresourcesforonlinetriggering,offlinemassreporcessinganduseranalysisjobs.