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  • 简介:AbstractIntheparametertrackingoftime-varyingsystems,theordinarymethodisweightedleastsquareswiththerectangularwindowortheexponentialwindow.Inthispaperweproposeanewkindofslidingwindowcalledthemultipleexponentialwindow,andthenuseittofittime-varyingGaussianvectorautoregressivemodels.Theasymptoticbiasandcovarianceoftheestimatoroftheparameterfortime-invariantmodelsarealsoderived.Simulationresultsshowthatthemultipleexponentialwindowshavebetterparametertrackingeffectthanrectangularwindowsandexponentialones.

  • 标签: EXPONENTIAL WINDOW rectangular WINDOW MULTIPLE EXPONENTIAL
  • 简介:Faraday-cupControlandMeasurementProgramBasedonMSWindows¥ZhangGuixuandLuXueqiuAnewfaraday-cupcontrolprogramwhichrunsonMSWindow...

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  • 简介:Li0.33MnO2cathodematerialwassynthesizedbysolidstatereaction.Thematerialshowedasmallcoherentdomainsizeabout10nmdeterminedbyX-raydiffractionandtransmissionelectronmicroscopy.Theelectrochemicalpropertiesofthematerialwerestudiedindifferentpotentialwindowsof3.5―2.0Vand4.3―2.0V.Anirreversibletransformationtospinelphasewasobservedintheinitialseveralcycles,whichwasmoreprominentoncyclingat4.3―2.0V.ElectrochemicalimpedancespectroscopyshowedthattheLi+diffusioncoefficientofthematerialwasabout2×10–9cm2/s.Li0.33MnO2showedareversibledischargecapacityof140and200mA·h/ginthepotentialwindowsof3.5―2.0Vand4.3―2.0V,respectively.Butthecapacityretentionat4.3―2.0Vwaspoorduetothethickerspinellayerformedonthematerialsurface.

  • 标签: 固相合成反应 电化学性能 Windows 正极材料 视窗 尖晶石相
  • 简介:Whenmeasurementsareperformedinhighspeed,small-scalecompressors,theuseofcurvedglasswindowsisrequiredinordertoavoidanymismatchbetweenthemeasurementwindowandthecasing.However,theglasscurvatureleadstoopticaldistortions,whichhinderacceptablemeasurementsandcanevenpreventtheacquisitionofanydata.Thus,anoriginalopticalassembly,whichconsistsininsertingasimpleandinexpensivecorrectivewindowbetweenthefrontallensoftheanemometerandtheshroudwindow,isproposed.Thewayofdeterminingthegeometriccharacteristicsandthepositionofthiscorrectivewindow,whichrestoresveryacceptablefoci,ispresentedinthepaper.Thereliabilityofthiscorrectiveopticalassemblyishighlightedbycomparativemeasurementsinatestcase.Usingsuchanopticalsetting,L2Fmeasurementswererealisedalongasection,downstreamoftheinletguidevane(IGV)ofatransoniccompressorstage.Thespatialresolutionleadstoagooddescriptionoftheinteractionofthewakewiththeobliqueshockemanatingfromtheleadingedgeoftherotor.Aphenomenologicalstudyofthewake/shockinteractionwithachangeofframeisrealisedusingthestreamwiseequationofthetransportofvorticity.

  • 标签: 空气压缩机 风速测量 曲线窗形