简介:ThispaperproposesanadaptivejointsourceandchannelcodingschemeforH.264videomulticastoverwirelessLANwhichtakesintoaccounttheusertopologychangesandvaryingchannelconditionsofmultipleusers,anddynamicallyallocatesavailablebandwidthbetweensourcecodingandchannelcoding,withthegoaltooptimizetheoverallsystemperformance.Inparticular,sourceresilienceanderrorcorrectionareconsideredjointlyintheschemetoachievetheoptimalperformance.Andachannelestimationalgorithmbasedontheaveragepacketlossrateandthevarianceofpacketlossrateisproposedalso.Twooverallperformancecriteriaforvideomulticastareinvestigatedandexperimentalresultsarepresentedtoshowtheimprovementobtainedbythescheme.
简介:ThelongtermaccessibilityofitsdataisanimportantconcernoftheDELPHIcollaboration.Itisourassumptionthatthestorageofthedataitselfwillbeaminorissueduetotheprogressinstoragetechnologies.ThereforeDELPHIfocusesonareorganisationofthedata,whichshouldprovideaflexibleandcoherentframeworkforphysicsanalysisinthefuture.ThispaperdescribesthecurrentstatusoftheIDEA(ImprovedDElphiAnalysis)projectwhichwillensureusabilityofDELPHIdataforfuturegenerationsofphysicists.
简介:Inadditiontodeploymentofthecommercialmanagementproducts,anumberofpublicandselfdevelopedtoolsaresuccessfullyusedatFermilabformonitoringofthecampusnetwork.Asuiteoftoolsconsistingofseveralprogramsrunninginadistributedenvironmenttomeasurenetworkparameterssuchasaverageround-triptime.traffic,throughput,errorrate,DNSresponsesandothersfromdifferentlocationsinthenetworkisused.Thesystemmaintainsacentralarchiveofdata,makesanalysisandgraphicalrepresentationavailableviaaweb-basedinterface.ThedevelopedtoolsarebasedonintegrationwithwellknownpublicsoftwareRRD,Cricketfping,iperf.
简介:TheneuralnetworkrealtimeeventselectionfortheDIRACewperimentatCERNispresented.Itcomprisesoftwoindependentparts.OneusesplasticscintillatorsandtheothertheverticalScintillatingFibres,Theglobaleventdecisionistakeninlessthan250ns.Signaleventsareselectedwithanefficiencyosmorethan0.99withabackgroundratereductionofabout2.
简介:Wepresentthepropagationofcylindricalwavesinthemediawhosepermittivityvarieswithtimeabruptlyorcontinuously.Bythemethodofvariableseparation,wederivethegeneralexpressionofelectricfieldofTM-polarizedwavesintwo-dimensionalspacewithexcitationofanypointatanytime.Withthisexpression,thesolutionforaspatiallyandtemporallydistributedsourcecanbeobtainedtheoretically.Thefocusingofreflectedwavesinthecrosssectionisshownwhenthemediaundergoesasuddenorcontinuouschange.Thewavepropagationintime-invariantmediacanbeconsideredasaspecialcaseofthemediaunderexponentialvariance.
简介:自相关函数并且有非线性的推迟时间的反馈的一个自治随机的系统跨关联被使用随机的模拟方法调查。在一个自治随机的系统的关联上二次的推迟时间的反馈和立方的推迟时间的反馈的角色之间有突出的差别。在二次的推迟时间的反馈下面,非线性的时间延期没能改进自治随机的系统的吵闹的状态,自相关单调地减少到零,并且跨关联的增加单调地到零与腐烂时间。在立方的推迟时间的反馈下面,非线性的时间延期能改进自治随机的系统的吵闹的状态;自相关和跨关联的表演期刊摆动和变细,最后与腐烂时间趋于到零。比较系统在之间的关联与非线性的推迟时间的反馈和线性推迟时间的反馈,我们发现非线性的推迟时间的反馈降低自治随机的系统的关联力量。
简介:Inthispaper,weconsiderthestationaryprobabilityandfirst-passagetimeofbiasedrandomwalkon1Dchain,whereateachstepthewalkermovestotheleftandrightwithprobabilitiespandqrespectively(0p,q1,p+q=1).Wederiveexactanalyticalresultsforthestationaryprobabilityandfirst-passagetimeasafunctionofpandqforthefirsttime.Ourresultssuggestthatthefirst-passagetimeshowsadoublepower-lawF~(N-1)~γ,wheretheexponentγ=2forN<|p-q|~(-1)andγ=1forN>|p-q|~(-1).Ourstudyshedsusefulinsightsintothebiasedrandom-walkprocess.
简介:Thestationarycorrelationfunctionandtheassociatedrelaxationtimeforageneralsystemdrivenbycrosscorrelatedwhitenoisesarederived,byvirtueofaStratonovich-likeansatz.Theeffectsofcorrelatednoisesontherelaxationtimeofabistablekineticmodelcoupledtoanadditiveandamultiplicativewhitenoisesarestudied.ItisprovedthatforsmallfluctuationstherelaxationtimeTcasafunctionofλ(thecorrelatedintensitybetweennoises)exhibitsverydifferentbehavioursforαD(αandD,respectively,standfortheintensitiesofadditiveandmultiplicativenoises).Whenα>D,Tcincreaseswithincreasingλ.Butwhenα
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简介:Theuniaxialratchetingbehaviorofapolyetherimide(PEI)polymer'TECAPEI'wasstudiedusingstress-controlledcyclicloadingatroomtemperature,includingbothcyclictension-compressionwithnon-zerotensilemeanstressandtension-unloadingtests.Theexperimentalobservationswerefocusedonthetime-dependentratchetingofthePEIpolymerrevealedincyclictestsatdiversestressratesandwithdifferentpeakstressholdingtimes.TheresultsshowedthatthePEIpolymershowsobviousratchetingdeformation;i.e.,theratchetingstrainaccumulatesprogressivelyinthetensiledirectionduringstress-controlledcyclictestswithnon-zeromeanstress.Theratchetingishighlydependentontheappliedmeanstressandstressam-plitude,andisalsocharacterizedbyastrongtime-dependencyduringthecyclicstressingatdiversestressratesandwithdifferentpeakstressholdingtimes.Thetime-dependentratchetingofthePEIpolymeriscausedmainlybyitsremarkableviscosity.AcomparisonoftheratchetingoccurringbeforeandbeyondtheultimatestresspointofthePEIpolymershowedthattheratchetingbeyondtheultimatestresspointismoresignificantthanthatoccurringbeforethatpoint.
简介:在氧化的缺氧的硫化物(ASO)的最佳的操作条件生物反应器被调查。最大的移动为硫化物评价;硝酸盐被发现是4.18kg/(m[3]·d);1.73kg/(m[3]·d)分别地。装载在固定底层集中整个减少的水力的保留时间(HRT)观察的率(LR)的volumetricalvolumetri比由在固定HRT增加底层集中的那些高。在ASO反应堆的硫化物氧化部分正在生产两硫酸盐;硫;但是生产的硫酸盐的数量是约三分之一硫的。这个过程能高容忍硫化物集中,当流入的集中直到580mg/L时,硫化物移动百分比总是在99%附近留下了。它容忍了因为当流入的集中在110mg/L上面被增加时,移动百分比落下到85%,相对降低硝酸盐集中。这个过程能容忍更短的HRT但是小心的操作被需要。自从当HRT从3.12h被减少到2.88h时,进程性能突然地败坏了,硝酸盐变换比硫化物变换对HRT更敏感。以便在反应堆避免亚硝酸根累积,流入的硫化物;硝酸盐集中应该在280mg/L被保留;67.5mg/L分别地。现在的生物工学为把硫化物从下水道移开是有用的;原油。