简介：Atransformertypeironcoresnubber,asaprotectivedeviceagainstthestraycapacitanceduringthebreakdowninEAST,isanalyzedindetail.Threekindsoftopologyarepresented.Thenwiththeanalysisforequivalentcircuit,therangesofthreekeyparameters,i.e.,secondarysideresistance,leakageinductanceandsnubberinductance,aredetermined.Byconsideringthesaturationofthemagneticmaterial,adesignprincipleisalsopresented.Anearly1:10coresnubberistested.Itisprovedthatahighpermeabilitycorewithsecondaryresistorcanrestrainthedischargecurrenteffectively.

简介：

简介：Inatmosphericradio-frequency(rf)discharges,theplasmaparameters,suchaselectrondensity,sheaththicknessandsheathvoltage,arenoteasytobeprobedexperimentally,whiletheelectricalcharacteristics,suchasimpedance,resistanceandreactance,arerelativelyconvenienttobemeasured.Inthispaperwepresentedasimpletheoreticalmodelderivedfromthefluiddescriptionofgeneratedplasmaswithoutconsideringthecircuitmodel,toinvestigatetherelationshipbetweentheplasmaimpedanceandplasmaparameters.Byintroducingarelaxationfrequency,theplasmaimpedancecouldbepredictedbyformulaspresentedinthisstudy,andthemeanelectrondensityandsheaththicknesscanalsobecalculatedfromthemeasuredorsimulatedimpedanceandreactance,respectively.

简介：Anexperimentaladvancedsuperconductingtokamak(EAST)operationwindowwiththelowerhybridcurrentdrive(LHCD)inH-modeisestimatedbyusingacore-SOL-divertor(C-S-D)modelvalidatedbythepresentEASTdivertorexperiments.Theoperationwindowconsistsoffourlimitsincludingtwousuallimits,oneofwhichisthemaximumallowableheatloadontothedivertorplate,andtwoadditionallimitsassociatedwiththeLHCD.ThepredictiveEASToperationwindowisnotqualifiedtofulfillitsmissionforhighinputpower.Toextendtheoperationwindow,gaspuffingandimpurityseedingarepresentedastwoeffectivemethods.Inaddition,theeffectoftheLHCDcurrentontheoperationwindowisalsodiscussed.OurnumericalanalysisresultsprovideareferenceforthesafeoperationofEASTexperimentswithLHCDinfuture.

简介：

简介：Itwasrecentlysuggestedthattheperiodicandfractalprecipitaionofcalciumsaltsandproteinsincholesterolgallstonesiscloselyrelatedtotheprocessofstoneformation.Thepresentstudyistomimictheprocessofgallstonegrowthinvitro.Wedemonstrateforthefirsttimethatathree-dimensionalstructureofperiodicrings(Liesegangring)and/orfractalpatternscanbeproducedbymetalionanddeoxycholateprecipitaitonwhicharesimilartogallstones.Precipitationinaperiodicpatternoccursmoreoftenthaninafractalstructure,UsingX-raydiffraction.polarizedlightmicroscope,Fouriertransform-infrared(FT-IR),andextendedX-rayabsorptionfinestructure(EXAFS),westudiedthepatternformationmechanismsofbothtypesofstructure.Theresultsindicatethattherateofnucleationinthecrystalgrowthisacrucialelementofaffectthepatternformation.Thepatternselectionbetweenperiodicandfractaltypedependsonthecrystalgrowthspeedandtherateofnucleation.

简介：Thenet-baryonnumberisessentiallytransportedbyvalencequarksthatprobethesaturationregimeinthetargetbymultiplescattering.Thenet-baryondistributions,nuclearstoppingpowerandgluonsaturationfeaturesintheSPSandRHICenergyregionsareinvestigatedbytakingadvantageofthegluonsaturationmodelwithgeometricscaling.Predicationsaremadeforthenet-baryonrapiditydistributions,meanrapiditylossandgluonsaturationfeaturesincentralPb+PbcollisionsatLHC.

简介：Atwo-dimensionalhybridcodeisdevelopedtomodelthetransportofahigh-currentelectronbeaminadenseplasmatarget.Thebeamelectronsaretreatedasparticlesanddescribedbyparticle-in-cellsimulationincludingcollisionswiththetargetplasmaparticles.Thebackgroundtargetplasmaisassumedtobeastationaryfluidwithtemperaturevariations.Thereturncurrentandtheself-generatedelectricandmagneticfieldsareobtainedbycombiningAmpere’slawwithoutthedisplacementcurrent,theresistiveOhm’slawandFaraday’slaw.Theequationsaresolvedintwo-dimensionalcylindricalgeometrywithrotationalsymmetryonaregulargrid,withcenteredspatialdifferencingandfirst-orderimplicittimedifferencing.Thealgorithmsimplementedinthecodearedescribed,andanumericalexperimentisperformedforanelectronbeamwithMaxwelliandistributionejectedintoauniformdeuterium-tritiumplasmatarget.

简介：Theaccuracyoflaser-inducedbreakdownspectroscopy(LIBS)quantitativemethodisgreatlydependentontheamountofcertifiedstandardsamplesusedfortraining.However,inpracticalapplications,onlylimitedstandardsampleswithlabeledcertifiedconcentrationsareavailable.Anovelsemi-supervisedLIBSquantitativeanalysismethodisproposed,basedonco-trainingregressionmodelwithselectionofeffectiveunlabeledsamples.Themainideaoftheproposedmethodistoobtainbetterregressionperformancebyaddingeffectiveunlabeledsamplesinsemi-supervisedlearning.First,effectiveunlabeledsamplesareselectedaccordingtothetestingsamplesbyEuclideanmetric.Twooriginalregressionmodelsbasedonleastsquaressupportvectormachinewithdifferentparametersaretrainedbythelabeledsamplesseparately,andthentheeffectiveunlabeledsamplespredictedbythetwomodelsareusedtoenlargethetrainingdatasetbasedonlabelingconfidenceestimation.Thefinalpredictionsoftheproposedmethodonthetestingsampleswillbedeterminedbyweightedcombinationsofthepredictionsoftwoupdatedregressionmodels.Chromiumconcentrationanalysisexperimentsof23certifiedstandardhigh-alloysteelsampleswerecarriedout,inwhich5sampleswithlabeledconcentrationsand11unlabeledsampleswereusedtotraintheregressionmodelsandtheremaining7sampleswereusedfortesting.Withthenumbersofeffectiveunlabeledsamplesincreasing,therootmeansquareerroroftheproposedmethodwentdownfrom1.80%to0.84%andtherelativepredictionerrorwasreducedfrom9.15%to4.04%.