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500 个结果
  • 简介:Multimediastreamingservedthroughpeer-to-peer(P2P)networksisboomingnowadays.However,theend-to-endstreamingqualityisgenerallyunstableduetothevariabilityofthestateofserve-peers.Ontheotherhand,proxycachingisabandwidth-efficientschemeforstreamingovertheInternet,whereasitisasubstantiallyexpensivemethodneedingdedicatedpowerfulproxyservers.Inthispaper,wepresentaP2PcooperativestreamingarchitecturecombinedwiththeadvantagesofbothP2Pnetworksandmultimediaproxycachingtechniquestoimprovethestreamingqualityofparticipatingclients.Inthisframe-work,aclientwillsimultaneouslyretrievecontentsfromtheserverandotherpeersthathaveviewedandcachedthesametitlebefore.Inthemeantime,theclientwillalsoselectivelycachetheaggregatedvideocontentsoastoservestillfutureclients.Theassociateprotocoltofacilitatethemulti-pathstreamingandadistributedutility-basedpartialcachingschemearedetailedlydis-cussed.Wedemonstratetheeffectivenessofthisproposedarchitecturethroughextensivesimulationexperimentsonlarge,Inter-net-liketopologies.

  • 标签: 分布式高速缓存 P2P网络 流媒体服务 体系结构
  • 简介:HL-2Atokamak(majorradiusR=165cm,minorradiusα=38-45cm)wassuccessfullyachievedsingle-nulldivertordischargewithgoodcontrolloftheplasmacurrentandpositioninexperiment.Parametersachievedinthiscompaignwereasfollows:toroidalmagneticfieldBT=1.4T,plasmacurrentIp=168kA,plasmaelectrondensityne=1.7×10^19/m^3,plasmaexisttimetp=920ms.

  • 标签: HL-2A 等离子体 光谱测量 偏滤器 稳定放电
  • 简介:AnelectroncyclotronresonanceheatingsystemwillbeconstructedinthenearfutureforECHandECCDinvestigationonHL-2Atokamak.ThenewECRHsystemwillprovideHL-2Awithapowercapabilityof1MWfor1satfrequencyof70GHz.Consequently,itisveryimportanttochooseasuitablegyrotronandsomecomponentsforHL-2AECRHsystem.

  • 标签: 电子回旋加热 电流驱动 核聚变 参数计算 ITER 等离子体
  • 简介:HfO2榆树被电子横梁蒸发在BK7玻璃底层上扔。在剩余压力和HfO2电影的结构上在100度C和400度C之间退火的影响被学习。系列,剩余压力和结构的小差别在在更低的温度退火以后被获得,这被发现。在在更高的温度退火以后,系列变到短波长,有增加退火的剩余压力增加温度。同时,雏晶尺寸增加,interplanardistance减少。光系列和剩余应力的变化对应于退火导致的结构的进化。

  • 标签: 退火 余力 氧化铪 薄膜
  • 简介:ReducingtheanthropogenicCO2emissionsfromfossilresourcecombustionandhumanactivitieshasbecomeoneofthemajorchallengeswearefacingtoday.BeyondthosepracticalapplicationsfortheutilizationofCO2,suchasthesynthesisofsalicylicacid,methanol,urea,NaHCO3-Na2CO3chemicalsandrecentlydevelopedpolycarbonatesynthesis,scientistsarestillseekingnewmaterialsandtechnologiesforefficientcapture,

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  • 简介:Visibleimageryisextremelyusefultooverviewtheedgeanddivertorstructure.Theplasmaconfigurationandthepositionofthestrikelinesonthetargetplatescanbealsoobservedbyimagingtechnique.Byimagingtheedgeorcoreplasmawithvisibleemissioninthedesiredwavelengthband,usuallywitha“tangential”view,theplasmapositioncanbedeterminedinprinciple.

  • 标签: HL-2A 等离子体 可见光成像 托卡马克装置 诊断方法
  • 简介:TheeffortonelectrochemicalreductionofCO2tousefulchemicalsusingtherenewableenergytodrivetheprocessisgrowingfastrecently.Inthisreview,weintroducetherecentprogressesontheelectrochemicalreductionofCO2insolidoxideelectrolysiscells(SOECs).Athightemperature,onlyCOisproducedwithhighcurrentdensitiesandFaradicefficiencywhilethereactoriscomplicatedandabettersealingtechniqueisurgentlyneeded.Thetypicalelectrolytessuchaszirconia-basedoxides,ceria-basedoxidesandlanthanumgallates-basedoxides,anodesandcathodesareintroducedinthisreview,andthecathodematerials,suchasconventionalmetal–ceramics(cermets),mixedionicandelectronicconductors(MIECs)arediscussedindetail.Inthefuture,togainmorevalue-addedproducts,theelectrolyte,cathodeandanodematerialsshouldbedevelopedtoallowSOECstobeoperatedattemperaturerangeof573–873K.Atthosetemperatures,SOECsmaycombinetheadvantagesofthelowtemperaturesystemandthehightemperaturesystemtoproducevariousproductswithhighcurrentdensities.

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  • 简介:X-γradiationbelongtotheionizingradiation.Ionizingradiationsinkstoenergyinorganismbutproduceadisservicetotheorganism.Justasmedicine,thedisserviceoftheradiationtowardsOrganismisdecidedbytoacceptradiationquantify,theradiationquantifywasnameddose.Radiationprotection'sbasicmissionsistowanttoresultthedosetofixquantify.InthissurveythedoseatworkplaceanditssurroundingsenvironmentsofHL-2Adevicewasmeasuredandtheassessmentwasgivenout.

  • 标签: X-γ辐射剂量 HL-2A 电离辐射 安全评价 磁约束受控热核聚变
  • 简介:以一个新方法在四维的欧几里德几何学的苏(2)杨工厂理论由分解苏(2)计量潜力,我们发现与一件马甲的isospin缺点有关的数字上的片刻命令参数能被Hopf索引和Brouwer度拓扑地使量子化。数字上的片刻只是在杨工厂理论的重要部门的isospin缺点的拓扑的费用的和,这也被显示出。

  • 标签: 拓扑量化 杨密SU(2)规范理论 瞬子 量子学
  • 简介:Tomeettherequirementoflong-timeacquisitionwithoutinterruptionsfortheplannednucleardecayexperimentsatCSRe,anewdataacquisitionsystemhasbeensuccessfullydevelopedin2016.DuringthebeamtimeinDec.2016,ournewsystemhasbeenrunningstablywithoutanyproblemsandcontinuouslyacquiringhundredsofdatawithoutanybreaks.Thewholesystemisbasedonaspectrumanalyzer(R&SFSVR7)andanIQrecorder(R&SIQR100).BothofthemareconnectedtoaserverviaEthernet.Thespectrumanalyzeracquiresthetime-domaininformationinthefrequencyrangeofinterestfromtheSchottkyresonator.TheIQrecordercollectstheinformationfromtheanalyzerandpacksitintodata.Oncethedatahavebeenentirelytransferredtotheserver,itwillimmediatelyberemovedfromIQrecorder.Thehigh-volumesolid-statedrive(1TB)ofIQrecorderallowsforavirtuallyunlimitedsizeofacquiredlestobestoredinpractice.Besides,inordertobypasstheunreliabletriggersystemofIQrecorder,webuiltanindependenttriggersystemwithamicrocontroller(ArduinoYun)totranslatetheTTLsignaltonetworkcommands.

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