简介:LetGbeap-seriesgroupandΩbeacompactsubgroupofG.Letλ(x,r)andλ,(x,r)beA-belp-poissontypekernelandproducttypekernelOnΩrespectively.Inthispaperwediscusstheap-proximationpropertiesofsuchkernels,givetheestimate5oftheirmoments,obtainthedirectandin-verseapproximationtheorems.
简介:ThePVCservesofmacroporoussulfoniccation-exchangeresinswerepreparedbythesulfonationofamacroporousPVCbeadwithconcentratedsulfonicacidorchlorosulfonicacid.theresultingsulfonicresinwasemployedintheinvestigationofcatalyticesterificationandsolfteningofwater,Theresultsshowthattheyieldsofestersreach60.0-84.4%accordingasdifferentfattyacidsandalcohols,therefractiveindexesofestersobtainedresemblethosereportedinthereferencesbasically,meanwhile,345Lsoftenedwaterwhichholds≤0.06mmol/Lhardnesswouldbepreparedby1Lwetsulfonicresinreusingfor4times.Theresultingsulfonicresinswouldhave1.6-2.0or2.5-3.0mmol/gexchangecapacitybyusingconcentratedsulfonicacidorchlorosulfonicacidassulfonatingagent,respectively,Thesulfonicresinhasamacroporousstructuretakingthemorphologywithagglomeratesofminutelysphericalgelparticlesascharacteristic.
简介:Inthispaper,opticalpulserepetitionratemultiplicationbasedonaseries-coupleddouble-ringresonatorisproposed.First,thespectralcharacteristicoftheseries-coupleddouble-ringresonatorissimulatedandtheoptimumcouplingcoefficientstoachieveaperiodicflat-toppassbandareobtained.Then,high-qualitypulserepetitionratemultiplicationisrealizedbyperiodicallyfilteringoutspectrallinesoftheinputpulsetrain.DifferentmultiplicationfactorsN2,3,4,5canbeobtainedbyadjustingtheringradii.Inaddition,comparedwithasingle-ringresonator,themultipliedoutputpulsetrainbyaseries-coupleddouble-ringresonatorexhibitsmuchbetterpoweruniformity.
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简介:Anovelmodelisproposedwhichcomprisesofabeambridgesubjectedtoanaxialloadandaninfiniteseriesofmovingloads.Themovingloads,whosedistancebetweentheneighbouringonesisthelengthofthebeambridge,coupledwiththeaxialforcecanleadthevibrationofthebeambridgetocodimension-twobifurcation.Ofparticularconcernisaparameterregimewherenon-persistencesetregionsundergoatransitiontopersistenceregions.Theboundaryofeachstriperepresentsabifurcationwhichcandrivethesystemoffakindofdynamicsandjumptoanotherone,causingdamageduetotheresultingamplitudejumps.TheGalerkinmethod,averagingmethod,invertiblelineartransformation,andnearidentitynonlineartransformationsareusedtoobtaintheuniversalunfoldingforthecodimension-twobifurcationofthemid-spandeflection.Theefficiencyofthetheoreticalanalysisobtainedinthispaperisverifiedvianumericalsimulations.
简介:Theboundaryvalueproblemofplatebendingproblemontwo-parameterfoundationwasdiscussed.Usingtwoseriesofthehigh-orderfundamentalsolutionsequences,namely,thefundamentalsolutionsequencesforthemulti-harmonicoperatorandLaplaceoperator,applyingthemultiplereciprocitymethod(MRM),theMRMboundaryintegralequationforplatebendingproblemwasconstructed.ItprovesthattheboundaryintegralequationderivedfromMRMisessentiallyidenticaltotheconventionalboundaryintegralequation.HencetheconvergenceanalysisofMRMforplatebendingproblemcanbeobtainedbytheerrorestimationfortheconventionalboundaryintegralequation.Inaddition,thismethodcanextendtothecaseofmoreseriesofthehigh-orderfundamentalsolutionsequences.
简介:<正>Someproblemsinusingv-supportvectormachine(v-SVM)forthepredictionofnonlineartimeseriesarediscussed.Theproblemsincludeselectionofvariousnetparameters,whichaffecttheperformanceofprediction,mixtureofkernels,anddecompositioncooperationlinearprogrammingv-SVMregression,whichresultinimprovementsofthealgorithm.ComputersimulationsinthepredictionofnonlineartimeseriesproducedbyMackey-GlassequationandLorenzequationprovidesomeimprovedresults.
简介:Aseriesof'hairy-rod'polyimides,BBPA(n),withmultiplealkylsidechainswaspreparedfrom3,3′,4,4′biphenyltetracarboxylicdianhydride(BPDA)and4,4′-biphenyldiaminesubstitutedinthe2,2′-positionswithbenzoate,whichwassubstitutedinthe3,4,5-positionswithethersidechainsofvaryinglengths.Thenumberofthemethyleneunits,n,inthesealkylsidechainswereinevennumbersrangingfrom8to18.Combiningtechniquesofone-dimensional(1D)and2Dwideanglex-raydiffraction,1DsmallangleX-rayscattering,differentialscanningcalorimetryexperiments,itwasfoundthatthisseriesof'hairy-rod'polyimidespossessamicro-phaseseparationbetweenthebackbonesandsidechains.Thisledtotheformationoforderedstructuresintwodifferentlengthscales,ofwhichbotharehexagonalpacking:oneisattributedtothealkylsidechainsonthesub-nanometerscale,andanotherisforthewholepolymerchainsonthenanometerscale.Thedevelopmentofthehexagonalstructureonthesub-nanometerscalewascriticallydependentuponthelengthsofthealkylsidechains.Threerelaxationprocesseswerecapturedbydynamicmechanicalanalysis,i.e.,segmentalmotionofthebackbones,α,themeltingofthesidechaincrystals,β1,whichexitsonlyforthematerialswithlongersidechains(n=18,16);andthesubglassrelaxationofsidechains,β2.Thepeakrelaxationtemperatureoftheαprocessdecreasedwithincreasingthelengthofsidechains,whiletheoneoftheβ2processincreased.Theactivationenergyoftheαrelaxationwasrelativelyindependentonthelengthofsidechain,whereas,β2processshowedtheincreasingofactivationenergywithincreasingthelengthofsidechains.
简介:Fivechiralstationaryphases(CSPs)wereusedtoseparatetheenantiomersofaseriesofO,O-diethyl(p-methyl-benzenesulfonamindo)-aryl(alkyl)-methylphosphonates.Achiralrecognitionmechanismwaspresentedtoexplaintheresolutionofthesecompounds.ResultsshowthatCSPwithstrongπ-acceptor3,5-dinitrobenzoylgroupandhighsterichindrancehasthebestresolutionabilityinchiralseparationofO,O-diethyi(p-methyl-benzenesulfonamindo)-aryl(alkyl)-methylphosphonates.WhenaCSPhasjustastrongπ-acceptor3,5-dinitrobenzoylorhighsterichindranceitdoesnothavegoodchiralresolutionability.ThechiralrecognitionismoredifficultwhentheCSPhasmorethanoneasymmetriccenter.
简介:Inthispaper,weshowthatnewmodifieddoublecosinetrigonometricsumsintroducedin[1]areinappropriate,theclassofdoublesequencesJdintroducedthereisunusableforsuchsumsandconsequentlytheresultsobtainedinitarecompletelyincorrect.WehereintroduceappropriatemodifieddoublecosinetrigonometricsumsmakingtheclassJdusableconsideringaparticulardoublecosinetrigonometricseries.