学科分类
/ 1
12 个结果
  • 简介:用图像点燃你的数码日志随着Blog和MSNSpece的肆虐流行,在朋友圈子中如果没在网上建个窝好像是件挺丢人的事儿。

  • 标签: 日志 DC BLOG MSN 图像
  • 简介:针对DC/DC的质子位移效应,选取具有抗TID能力的DC/DC器件作为试验样品,在3MeV质子辐照条件下获取了器件的失效位移损伤剂量.结果表明,DC/DC功能失效是PWM控制器输出异常导致的.通过等效^60Coγ辐照及退火试验,排除了TID效应的影响,确定器件功能失效是由位移损伤引起的.高温退火后器件功能恢复,并立即对该器件进行了测试.结果表明,输出电压、电压调整度、负载调整度、交叉调整度、纹波及负载跃变时的输出电压均大幅衰退.利用这些敏感参数,获取了位移损伤导致的电源性能衰退模式.根据位移损伤缺陷类型及退火温度,分析了DC/DC的退火规律,可为DC/DC质子辐射损伤模拟试验方法的建立及其空间应用提供依据.

  • 标签: DC/DC 位移损伤效应 电离损伤效应 位移缺陷 退火
  • 简介:由阳光等在我们证明近似近似方法forDC功能的集中的这篇论文求婚了[6]。我们的分析也允许对待准确方法。Wethen在DC功能的第二个部件是可辨的并且提供证明了我们的方法的效率的一些计算经验的情况中建议有趣的结果。

  • 标签: DC最小化 临界点 次微分 近端成像 数学分析
  • 简介:Aself-consistenthybridMonteCarloFluidmodelispresentedtodescribethenitrogendcglowdischarge.ThemovementoffastelectronsissimulatedbytheMonteCarlomethodwhilethedynamicsofslowelectronsandionsisbyfluidequations.Thespatialfeaturesofthechargedspeciesandthecorrespondingelectricfieldthroughoutthedischargehavebeencalculated,whichincludethecreationratesofionsandslowelectrons,densitiesofthechargedspecies,theelectricfieldandthepotentialdistribution.Thesecloselyrelatedresultscangiveaselfconsistentexplanationofthedischargecharacteristicsthroughoutthespaceofnitrogendcglowdischarge.Thecalculatediondensityisalsocomparedwiththecorrespondingexperimentalresult.

  • 标签: 氮直流辉光放电 自洽描述
  • 简介:Non-transferreddcarcplasmageneratorsarewidelyusedinmaterialsprocessing.Theyaregenerallyconsideredsteadily-operatingdevises.However,unsteadyphenomenadoexistinthem,andmaycausenon-idealeffectsinprocesseswhichrequirehighcontrollabilityandreproducibility.Theseunsteadyphenomenacancauseparameterfluctuationsinthearcandtheplasmajet,someofwhichhavebeenstudiedinrecentyears.Severaltypesandmechanismsofthesephenomenahavebeenidentified.Thispaperreviewst...

  • 标签:
  • 简介:我们报导当前的摆动anddc-voltage-controlled的详细理论研究在做的GaAs/AlAs反响的通道超点阵在下面的混乱动力学交叉电并且磁场。当超点阵在否定微分速度区域被偏导时,当前的自激振荡与合适的做的集中被观察。当前的摆动模式和摆动频率能被dc电压偏爱影响,做密度,并且磁性删除。什么时候交流电与固定振幅删除,频率也被用于系统,不同非线性的性质与dcvoltage的变化出现在外部电路偏爱。我们小心地与不同检测混乱的方法学习这些非线性的性质。

  • 标签: 电流振荡 直流电压约束混乱动力学 半导体超晶格 电磁场
  • 简介:根据共轭函数和DC规划的性质,给出一类特殊DC规划的共轭对偶并讨论其对偶规划的特殊性质,然后利用该性质,把对这类特殊DC规划的求解转化为对一个凸规划的求解.

  • 标签: 共轭函数 DC规划 共轭对偶 凸规划
  • 简介:Weproposeapositionsensorlesscontrolschemeforafour-switch,three-phasebrushlessDCmotordrive,basedonthezerocrossingpointdetectionofphaseback-EMFvoltagesusingnewlydefinederrorfunctions(EFs).Thecommutationin-stantsare30°afterdetectedzerocrossingpointsoftheEFs.DevelopedEFshavegreatermagnituderatherthanphaseorlinevoltagessothatthesensorlesscontrolcanworkatalowerspeedrange.Moreover,EFshavesmoothtransitionsaroundzerovoltagelevelthatreducesthecommutationerrors.EFsarederivedfromthefilteredterminalvoltagesvaoandvbooftwolow-passfilters,whichareusedtoeliminatehighfrequencynoisesforcalculationoftheaverageterminalvoltages.Thefeasibilityoftheproposedsensorlesscontrolisdemonstratedbysimulationandexperimentalresults.

  • 标签: 无刷直流电动机 四开关逆变器 传感控制器 反电势 数字信号处理
  • 简介:Thelowfrequencylinecomponentsoftheradiatednoisefromanunderwatertargetusuallyhavebothhighspectrumlevelandsustainedstability.Thisfeaturecouldbeusedtoincreasethedetectionperformanceofconventionalbroadbandenergyintegrationmethod.Therequiredspectrumlevelistheoreticallydiscussedwhenthedetectionperformanceoftheknownlinedetectionisbetterthanthatofbroadbandenergyintegrationmethod.Undertheconditionofthetargetcanbedetectedinlinespectrumband,therelationshipbetweenthelinespectrumlevelandsignaltonoiseratio(SNR)isalsodiscussed.ThispaperproposesalinespectrumtargetdetectionmethodthatamatrixusingDCjumptofluctuationsratiosofsub-bandspatialspectrumandbeamspaceoutputisconstructed.Thismatrixactsasafilterthatthelinespectrumtargetwithcertainfrequencyandazimuthispassedatmost.Byfusingwiththeothersubbandresults,theconventionaldetectionperformancecanbeimproved.Atthesametime,theapplicableconditionanddetectionperformanceareanalyzedinthepaper.Thesimulationandtheseatrialdataprocessingresultsshowthatthealgorithmcaneffectivelyextractweakgoallinespectrumtargetundertheconditionofmulti-interference.Thealgorithmdoesn’tneedmulti-framestatisticsandthedetectionperformanceisclosertotheoptimallinespectrummethod.

  • 标签: 检测性能 波束空间 波动率 空间谱 目标融合 直流
  • 简介:Asidechainliquidcrystallinecopolysiloxane,whichwouldshowelectro-opticeffectsasknownfromlowmassliquidcrystal,wassynthesizedbyhydrosilylationreaction,andthetwohomologousmonomerswithdifferentlengthspacerscontainingSchiff’sbasemesogenwith—NO2terminatedgroupweregraftedtoapolysiloxanemainchain.Residualmonomerincrudeproductiseffectiveinreinforcingtheresponsetoanelectricfieldoverthatofpurepolymericliquidcrystal.

  • 标签: Liquid Crystalline POLYSILOXANE Schiff’s BASE MESOGENS