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76 个结果
  • 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:Thestudyofnucleonresonanceisanimportanttopicinhadronphysics.Themostimportantwaytostudythenucleonresonancesisthecollisionofthephotonandnucleon.Uptonow,theknowledgeaboutthenucleonresonancesaround2GeVisstillscarce.Recently,theCLASCollaborationatJeffersonNationalAcceleratorFacilityreleasedtheirexclusivephotoproductioncrosssectionsfortheΛ(1520),Σ0(1385)andΛ(1405)forenergiesfromnearthresholduptoacenterofmassenergyWof2.85GeVwithlargerangeoftheKproductionangle[1].SincethethresholdforthephotoproductionofΛ(1520)isabout2.01GeV,thenewexperimentaldatawithhighprecisionreleasedbytheCLASCollaborationprovideanopportunitytostudythenucleonresonancesabove2GeV.

  • 标签: EXPERIMENTAL ACCELERATOR PHOTON RANGE MOST is
  • 简介:就有确定的标准的信息技术的增加的使用而言,例如在现代工业自动化的TCP/IP和XML,我们在场有FPGA(可编程的门穿的域)的一个高成本效率解决方案一个新奇可靠即时数据传输系统的实现基于环保协会(为植物自动化的以太网)协议和IEEE1588标准。这个联合罐头提供在自动化设备之间的更可预言、即时的通讯和在设备之间的精确同步。设计环保协会系统在XilinxSpartan3XC3S1500上被验证了,它消费了75%全部的片。试验性的结果证明新奇工业监督制度完成高同步精确并且提供在主人设备和奴隶之间的1.59-μs标准偏差。如此的一个即时数据传输系统是以比较地低的价格基于以太网要求精确同步的自动化设备的一个优秀候选人。

  • 标签: IEEE 1588 精确同步 EPA 数据转换
  • 简介:TostudytheinteractionbetweentheplasmaandwaveintheLHCDandECRHexperimentsonHL-2A.Itisnecessarytocontroltheexperimentsbycomputerinordertocarryontheexperimentseasilyandsafely.ThemaintaskofthecomputercontrollingsystemfortheLHCDexperimentinHL-2Aistomonitorthewholesystemoperation,

  • 标签: HL-2A 等离子体 波加热 微机控制 数据采集
  • 简介:AnewmethodisproposedtocalculatetheGrüneisenparameterdirectlyfromtheexperimentalHugoniotdata,withoutanyassumptiononthelatticevibrationalmodeofthematerialbeingstudied.Comparedwiththeresultscalculatedbythemethodsproposedpreviously,thevaluesoftheGrüneisenparametercalculatedhavethreedistinguishablefeaturesthatsupporttherationalityofthemethod.Anewphenomenonthatthelatticevibrationalmodechangeswiththethermodynamicstateofthesolidhasbeenfirstobservedfromthecalculatedresults,whichimpliesthatthematerialparameterg,characterizingthelatticevibrationalmode,ismaterialdependentratherthanamaterialconstant.

  • 标签: 固体 压缩 Grüneisen方程
  • 简介:WefallintodisusetheJUHUsystembasedonthePDP/11computerforRSX11Moperationsystem,andupdateourmulti-parameterdataaequisitionandanalysissystem’shardwareandsoftwarebasedonVAXIIcomputerandOpenVMSoperationsystem,makeitadaptedtotherecentphysicsexperiment.Inthispaper,wedescribetheupdatedinulti-parameterdataacquisitionandanalysissystem’shardware,softwareconfigurationandsystemfunction.

  • 标签:
  • 简介:DSPsarewidelyusedindataacquisitionsystemsonneutronspectrometersattheIBR-2pulsedreactor.Inthisreportseveralelectronicblocks,basedontheDSPoftheTMS320CXXXXfamilybytheTIfirmandintendedtosolvedifferenttasksinDAQsystems,aredescribed.

  • 标签: 中子散射实验 中子能谱仪 脉冲反应器
  • 简介:Theobjectiveofthisstudywastoobtainspatialdistributionmapsofpaddyricefieldsusingmulti-datemoderate-resolutionimagingspectroradiometer(MODIS)datainChina.Paddyricefieldswereextractedbyidentifyingtheuniquechar-acteristicofhighsoilmoistureinthefloodingandtransplantingperiodwithimprovedalgorithmsbasedonricegrowthcalendarregionalization.Thecharacteristiccouldbereflectedbytheenhancedvegetationindex(EVI)andthelandsurfacewaterindex(LSWI)derivedfromMODISsensordata.Algorithmsforsingle,early,andlatericeidentificationwereobtainedfromselectedtypicaltestsites.Thealgorithmscouldnotonlyseparateearlyriceandlatericeplantedinthesamefields,butalsoreducetheuncertainties.ThearealaccuracyoftheMODIS-derivedresultswasvalidatedbycomparisonwithagriculturalstatistics,andthespatialmatchingwasexaminedbyETM+(enhancedthematicmapperplus)imagesinatestregion.Majorfactorsthatmightcauseerrors,suchasthecoarsespatialresolutionandnoisesintheMODISdata,werediscussed.Althoughnotsuitableformonitoringtheinter-annualvariationsduetosomeinevitablefactors,theMODIS-derivedresultswereusefulforobtainingspatialdistributionmapsofpaddyriceonalargescale,andtheymightprovidereferenceforfurtherstudies.

  • 标签: 中等分辨率成像光谱仪 MODIS数据 水稻田 中国 空间分布图 脆弱性指数
  • 简介:WepresentseveralcomparisonsofGEANT4simulationswithtestbeamdataandGEANT3simulationsfordifferentliquidargon(LAr)calorimetersoftheATLASdetector,Allrelevantpartsofthetestbeamsetup(scintilators,multiwireproportionalchambers,cryostatetc.)aredescribedinGEANT4aswellasinGEANT3.MuonandelectrondataatdifferentenergieshavebeencomparedwithMonteCarloprediction.

  • 标签: ATLAS实验 电磁量热器 液态氩量热器 探测束数据模拟
  • 简介:TheHongKongObservatory(HKO)provideslow-levelturbulencealertingservicefortheHongKongInternationalAirport(HKIA)throughthewindshearandturbulencewarningsystem(WTWS).IntheWTWS,turbulenceintensitiesalongtheflightpathsoftheairportareestimatedbaseduponcorrelationequationsestablishedbetweenthesurfaceanemometerdataandtheturbulencedatafromresearchaircraftbeforetheopeningoftheairport.Theresearchaircraftdataarenotavailableonday-to-daybasis.Theremotesensingmeteorologicalinstruments,suchastheDopplerlightdetectionandranging(LIDAR)andradar,maybeusedtoprovidedirectmeasurementsofturbulenceintensitiesovertherunwaycorridors.TheperformancesofLIDAR-andradar-basedturbulenceintensitydataarestudiedinthispaperbasedonactualturbulenceintensitymeasurementsmadeon423commercialjetsforatypicalcaseofterrain-inducedturbulenceinassociationwithatyphoon.Itturnsoutthat,withthetuningoftherelativeoperatingcharacteristic(ROC)curvebetweenhitrateandfalsealarmrate,theLIDAR-basedturbulenceintensitymeasurementperformsbetterthantheanemometer-basedestimationofWTWSforturbulenceintensityatmoderatelevelorabove.Ontheotherhand,theradar-basedmeasurementdoesnotperformaswellwhencomparedwithWTWS.BycombiningLIDAR-andradar-basedmeasurements,theperformanceisslightlybetterthanWTWS,mainlyasaresultofcontributionfromLIDAR-basedmeasurement.Asaresult,theLIDAR-basedturbulenceintensitymeasurementcouldbeusedtoreplaceanemometer-basedestimatefornon-rainyweatherconditions.Furtherenhancementsofradar-basedturbulenceintensitymeasurementinrainwouldbenecessary.

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  • 简介:SISAK是国内外目前应用最广泛的短寿命同位素快化分离技术之一,在裂变产物、超重元素、远离β稳定线的非稳核研究方面有着广泛的应用。SISAK技术最新的发展主要集中在配套设备和计算机控制上。我们研制了一套以S7-200PLC为核心的SISAK自动控制系统,其组成和控制方案简单可靠,已在冷实验中取得了很好的效果。

  • 标签: SISAK 短寿命核素分离 PLC 自动控制