简介：AcalibratingdevicefortheRogowskicoilisdeveloped,whichcanbeusedtocal-ibratetheRogowskicoilhavingapartialresponsetimewithintensofnanoseconds.Itskeycomponentisastepcurrentgenerator,whichcangeneratetheoutputwitharisetimeoflessthan2nsandadurationoflargerthan300ns.Thestepcurrentgeneratoriscomposedbyapulseformingline(PFL)andapulsetransmissionline(PTL).ATEM(transverseelectromagneticmode)coaxialmeasurementunitisusedasPTL,andthecoiltobecalibratedandthereferencedstandardRogowskicoilcanbefixedintheunit.TheeffectofthedimensionsoftheTEMunitisdiscussedtheoreticallyaswellasexperimentally.

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简介：Anovelandefficientmethodfordecomposingasignalintoasetofintrinsicmodefunctions(IMFs)andatrendisproposed.Unliketheoriginalempiricalmodedecomposition(EMD),whichusessplinefitstoextractvariationsfromthesignalbyseparatingthelocalmeanfromthefluctuationsinthedecomposingprocess,thisnewmethodbeingproposedtakesadvantageofthetheoryofvariablefiniteimpulseresponse(FIR)filteringwherefiltercoefficientsandbreakpointfrequenciescanbeadjustedtotrackanypeak-to-peaktimescalechanges.TheIMFsateresultsofamultiplevariablefrequencyresponseFIRfilteringwhensignalspassthroughthefilters.Numericalex-amplesvalidatethatincontrastwiththeoriginalEMD,theproposedmethodcanfine-tunethefrequencyresolutionandsuppressthealiasingeffectively.

简介：Adoublycladdingsingle-modefiberhumiditysensorisfabricatedbyagarose.Thesensorhasaninsertionlossof0.08dBandapowerchangeof17.83dB.Theresponsesofthesensortoarelativehumidity(RH)rangeform30%to100%atatemperaturerangeform25to34Carevalidated.TheexperimentsdemonstratethattheabsorbabilityofagarosegeltomoisturedecreaseswithincreasingRHinmeasuredgas.Weproposeacalibrationmethodthatuseslookuptablesandconstructacorrespondingcalibrationmatrix.Usingthesensor,weconductreal-timemonitoringofRHinfreshconcreteduringitshardeningprocess.