简介：ThereisnoaccurateanalyticalapproachfortheacousticperformancepredictionofHelmholtzresonatorwithconicalneck,whichhasbroadbandacousticattenuationperformanceinthelowfrequencyrange.Topredicttheacousticperformanceoftheresonatoraccurately,ageneraltheorymodelbasedontheone-dimensionalanalysisapproachwithacousticlengthcorrectionsisdeveloped.Thesegmentationmethodisusedtocalculatetheacousticparametersforsoundpropagationinconicaltubes.Andthen,anapproximateformulaisdeducedtogiveaccuratecorrectionlengthsforconicaltubeswithdifierentgeometries.Thedeviationsoftheresonancefrequencybetweenthetransmissionlossresultsobtainedbythegeneraltheorywithacousticlengthscorrectionandtheresultsfromthefiniteelementmethodandexperimentsarelessthan2Hz,whichismuchbetterthantheresultsfromone-dimensionalapproachwithoutcorrections.Theresultsshowthatthemethodofacousticlengthcorrectionfortheconicalneckgreatlyimprovedtheaccuracyoftheone-dimensionalanalysisapproach,anditwillbequickandaccuratetopredictthesoundattenuationpropertyofHelmholtzresonatorwithconicalneck.

简介：Aquasi-steadymodeldescribingaerodynamicsofhoveringRuby-throatedhummingbirdsispresentedtostudyextentofthelow-ordermodelinrepresentingtheflowphysicsofthebirdandalsotoseparatelyquantifytheforcesfromthetranslational,rotational,andaccelerationeffects.Realisticwingkinematicsareadoptedandthemodeliscalibratedagainstcomputationalfluiddynamics(CFD)simulationsofacorrespondingrevolving-wingmodel.Theresultsshowthatthequasi-steadymodelisabletopredictoverallliftproductionreasonablywellbutfailstocapturedetailedforceoscillations.Thedownstroke-upstrokeasymmetryisconsistentwiththatinthepreviousCFDstudy.Furtheranalysisshowsthatsignificantrotationalforceisproducedduringmid-strokeratherthanwingreversal.

简介：金属橡胶材料的健全吸收表演理论上并且试验性地被学习。声学的阻抗率和健全吸收系数基于金属橡胶材料的声学的参数被导出。结构常数，压缩的可能性模量和结构的参数的关系试验性地被调查。结果证明有一样的吝啬的孔直径的金属橡胶的标本有一样的结构常数。为一样的结构的参数，金属橡胶材料的压缩的可能性模量在某些频率范围是近似不变的。计算声学的参数在对试验性的结果的好同意，表明理论模型的有效性。

简介：Therearemanyinneritemsinvacuumvessel,andhundredsofsealsonthevesselbortsintheHL-2Atokamak,soitisdifficulttogetexcellentvacuum.Duringtheengineeringtestin2002,theresultsofquadrupolemassspectrometershowedthatthepartialpressuresofoxygenandH2Owerehigherthannormalvalue,someleaksontheupperMP3coiljacketsandportsealshadbeendetected.Inordertocarryoutgooddischargeexperiment,thegoodvacuumandwallconditionmustbemaintained.

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简介：Theimpactsofthethickness,thespecificacousticimpedanceandthemechanicallossfactorofthebackingontheperformanceofthethicknessmodepiezoelectrictransduceraresystemicallystudied,whicharefocusedontheeffectiveelectromechanicalcouplingcoefficientandthemechanicalqualityfactornearthecenterfrequency.Theresultsshowthatwithcontinuousincreasingofthebackingthickness,theeffectiveelectromechanicalcouplingcoefficientandthemechanicalqualityfactorarefoundrapidlydeclinedbyoscillationway.Withtheincreaseofthedifferencevalueoftheacousticimpedancebetweenthebackingmaterialandthepiezoelectricmaterial,theeffectiveelectromechanicalcouplingcoefficientdeceasesandthemechanicalqualityfactorincreases.Underconditionthatthethicknessofthepiezoelectricmaterialisfixed,theeffectiveelectromechanicalcouplingcoefficientisfounddeclinedwiththeincreaseofthemechanicallossfactorbymonotonousway.Themechanicalqualityfactorhasminimumvalueandtheelectriccharacteristiccurvetendstobesmoothinagivenfrequencyrange.Theequivalentcircuittheoryresultisingoodagreementwiththeonesbyfiniteelementmethodandtheexperimentalresults.Theworkmentionedaboveprovidesatheoreticalguidanceforthedesignandexperimentalfabricationofthethicknessmodepiezoelectrictransducer.

简介：Thispaperpresentsaperformanceanalysisofaccessingtagdataclusteredintwodifferentways,namelyevent-wiseclustering(generictag)vs.attribute-wiseclustering(slicedtag).Theresultsshowthatespecially"Prefetch-optimisation"resultsinanadditionalperformancegainofslicedtagsovergenerictagswhenonlyasubsetofallthetagattributesisaccessed.

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简介：为了开发一个双人脚踏车弹头，那能有效地破坏具体目标，这篇论文借助于实验与不同的锥角度和班机材料探索塑造的费用的穿入表演进具体目标。穿入过程和由塑造的费用和动能射弹的具体目标的破坏机制被分析并且比较。试验性的结果建议运动精力充沛的射弹和塑造的充电能够破坏损坏的具体目标，而是大小是不同的。与动能射弹相比，塑造的费用有穿入的更多的重要效果进目标，并且引起很大的spalling区域。因此，塑造的费用对双人脚踏车弹头的第一阶段的充电相当合适。当洞直径变得更大时，随塑造的费用班机锥角度的增加，穿入的深度逐渐地减少，这也被发现。有铜班机的穿入深度比铝班机大，但是洞直径相对更小，并且有钢班机的塑造的起诉在上述二诉讼之间。有100°的一个锥角度的塑造的费用能形成喷气射弹费用(JPC)。与JPC，有具体目标上的最佳深度和直径的一个洞能被形成，它保证秒阶段弹头顺利渗透进洞并且在最佳深度爆炸在具体目标完成破坏的需要的水平。

简介：Inordertoimprovetheperformanceofawellsturbinetheeffectofguidevaneswithvariousgapsbetweenturbinerotorandguidevanehasbeenclarifiedbymodeltestingandnumericalsimulation.Theresultshavebeencomparedwiththoseofthecasewithoutguidevanes,ItisfoundthattheoverallCharacteriticsareconsiderablyimprovedbytheinletguidevanes.Furthermore,asuitablechoiceofdesignfactorforthegaphasbeensuggested.

简介：Weevaluatetheinfluenceofthethermallyassistedtunneling(TAT)mechanismonchargetrappingmemory(CTM)cellperformancebynumericalsimulation,andcomprehensivelyanalysetheeffectsofthetemperature,trapdepth,distributionoftrappedcharge,gatevoltageandparametersofTATonerasing/programmingspeedandretentionperformance.TATisanindispensablemechanisminCTMthatcanincreasethedetrappingprobabilityoftrappedcharge.OurresultsrevealthattheTATeffectcausesthesensitivityofcellperformancetotemperatureanditcouldaffecttheoperationalspeed,especiallyfortheerasingoperation.TheresultsshowthattheretentionperformancedegradescomparedwithwhentheTATmechanismisignored.

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简介：RapidgrowthprocessingofKDPcrystalswasimprovedbyemployingcontinuousfiltrationtoeliminatebulkdefects.TheperformancesoftheKDPcrystals,includingscatteringdefects,laserdamageresistanceandtransmittance,weremeasuredandanalyzed.Comparedwithrapid-grownKDPwithoutcontinuousfiltration,thetransmittanceinthenearinfraredwasincreasedbyatleast2%,almostallof‘micronsize’defectswereeliminatedand‘sub-micronsize’defectsweredecreasedbyapproximately90%.Laserdamagetestingrevealedthatthelaser-induceddamagethresholds（LIDTs）,aswellastheconsistencyoftheLIDTsfromsampletosample,wereimprovedgreatly.Moreover,itidentifiedthat‘micronsize’defectsweretheprecursorswhichinitiatedlaserdamageatrelativelowerlaserfluence(4–6Jcm-2),andtherewasalowercorrelationbetweensmallersizescatteringdefectsandlaserdamageinitiation.TheimprovedconsistencyintheLIDTs,attributedtoeliminationof‘micronsize’defects,andLIDTenhancementoriginatedfromthedecreasedabsorptionoftheKDPcrystals.

简介：Afiniteelement-Helmholtzintegralhybridmethodhasbeendevelopedtocalculatetheelectro-acousticperformanceofafinitelengthcylindricaltransducerimmersedinwater.Thenumericalstudyconcernedwithelectricalimpedancesandbeampatternsofthetransducerispresented.Experimentaldataareshowntosupportthenumericalstudy.

简介：Thispaperperformsanumericalsimulationofthree-dimensionalflowfieldinacentrifugalcompressorwithlonginletandoutletpipesusingCFXsoftware.Byarrangingvirtualprobesatdifferentpositionsinbothinletandoutletplanes,theaerodynamicperformanceofthecentrifugalcompressorismeasuredandcomparedwitheachother.Theneffectsofmeasuringpositionsonmeasurementresultsarediscussed.Theresultsshowthatitwillgeneratenotablemeasuringerrorsofthepressureratioandefficiencyiftheinlettotalpressureismeasuredusingasingle-pointprobe.Theinlettotalpressuredatacanbeaccuratewhentheyaremeasuredusinga3-pointrake.Theoutlettotalpressureandtotaltemperaturedatacannotbeaccurateiftheyarerespectivelymeasuredatonecircumferentialpositionevenusingamulti-pointrake.Increasingtangentialmeasuringpositionsattheoutletiseffectivetoimprovethetestaccuracy.Whentheoutlettotalpressureandtotaltemperaturearerespectivelymeasuredat3tangentialpositions,thedatacanbealmostaccurate.

简介：UnderstandinghowtheInternetisusedbyHEPiscriticaltooptimizingtheperformanceoftheinter-labcomputingenvironment.Typicallyuserequirementshavebeendefinedbydiscussionsbetweencollaborators.However,lateranalysisoftheactualtraffichasshownthisisoftenmisunderstoodandactualuseissignificantlydifferenttothatpredicted.Passivemonitoringoftherealtrafficprovidesinsightintothetruecommunicationsrequirementsandtheperformanceofalargenumberofalargenumberofinter-communicatingnodes.ItmaybeusefulinidentifyingperformanceproblemsthatareduetofactorsotherthanInternetcongestionespeciallywhencomparedtoothermethodssuchasactivemonitoringwheretrafficisgeneratedspecificallytomeasureitsperformance.Controlledactivemonitoringbetweendedicatedserversoftengivesanindicationofwhatcanbeachievedonanetwork,Passivemonitoringoftherealtrafficgivesapictureofthetrueperformance.ThispaperwilldiscussthemethodandresultsofcollectingandanalyzingflowsofdataobtainedfromtheSLACInternetborder,TheuniquenatureofHEPtrafficandtheneedsoftheHEPcommunitywillbehighlighted.Theinsightsthishasbroughttounderstandingthenetworkwillbereviewedandthebenefitiscanbringtoengineeringnetworkswillbediscussed.

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简介：细胞的神经/非线性的网络(CNN)是为图象和录像信号处理的一个强大的工具，机器、生物的视觉。这篇论文与在二进制图象提取关上的域的性能介绍一种CNN，并且为设计如此的一种CNN的模板给一个一般方法。一条定理为决定为实现的参数间隔规定了分别地处理功能的图象提供参数不平等。在二进制规模图象提取关上的域的Examplesfor被给。

简介：TheTerabyteAnalysisMachineProjectisDevelopinghardwareandsoftwaretoanalyzeTerabytescaledatasets.TheDistanceMachineframeworkprovidesfacilitiestoflexiblyinterfaceapplicationspecificindexingandpartitioningalgorthmstolargescientificdatabases.

简介：TheBaBarCopyProgram(bbcp)isanexcellentrepresentativeofpeer-to-peer(P2P)computing.Itisalsoapioneeringapplicationofitstypeinthep2parena.Builtuponthefoundationofitspredecessor,SecureFastCopy(sfctp),bbcpincorporatessignificantimprovementsperformanceandusability,Aswithsfcp,bbcpusecsshforauthentication;providinganelegantandsimpleworkingmodel-ifyoucansshtoalocation,youcancopyfilestoorfromthatlocation.Tofullysupportthisnotion,bbcptransparentlysupports3rdpartycopyoperations.Theprogramalsoincorporatesseveralmechanismtodealwithfirewallsecurity;thebaneofP2Pcomputing,Toachievehighperformanceinawideareanetwork,bbcpallowsausertoindependentlyspecily,thenumberofparallelnetworkstreams,tcpwindowsize,andthefileI/Oblockingfactor.Usingtheseparametersdataispipelinedfromsourcetotargettoprovideauniformtrafficpatternthatmaximizesrouterefficiency.Forimprovedrecoveralbiltiy,bbcpalsokeepstrackofcopyoperationssothatanoperationcanberestartedfromthepointoffailureatalatertime;minimizingtheamountofnetworktrafficintheeventofacopyfailure,Here,wepresetthebbcparchitecture,it'svariousfeatures,andthereasonsfortheirinclusion.