简介:ThisarticledescribesalocalerrorestimatorforGlimm'sschemeforhyperbolicsystemsofconservationlawsandusesittoreplacetheusualrandomchoiceinGlimm'sschemebyanoptimalchoice.Asaby-productofthelocalerrorestimator,theprocedureprovidesaglobalerrorestimatorthatisshownnumericallytobeaveryaccurateestimateoftheerrorinL1(R)foralltimes.Althoughthereispartialmathematicalevidencefortheerrorestimatorproposed,atthisstagetheerrorestimatormustbeconsideredad-hoc.Nonetheless,theerrorestimatorissimpletocompute,relativelyinexpensive,withoutadjustableparametersandatleastasaccurateasotherexistingerrorestimators.Numericalexperimentsin1-DforBurgers'equationandforEuler'ssystemareperformedtomeasuretheasymptoticaccuracyoftheresultingschemeandoftheerrorestimator.
简介:<正>InthepresentnotethealgebraicindependenceofvaluesofseveralMahlerserieswithcertainparticularanddifferentparametersatalgebraicpointsisestablishedbymeansofatypicalapproximationmethodhandlingtheLiouvilletypeseries.
简介:InthispaperwediscusstheconvergenceofamodifiedNewton’smethodpresentedbyA.Ostrowski[1]andJ.F.Traub[2],whichhasquadraticconvergenceorderbutreducesoneevaluationofthederivativeateverytwostepscomparedwithNewton’smethod.Aconvergencetheoremisestablishedbyusingaweakconditiona≤3-2(21/2)andasharperrorestimateisgivenabouttheiterativesequence.
简介:LetH1andH2beseparableHilbertspaces,andB(H1,H2)allofboundedlinearoperatorsfromH1intoH2.Inthisnote,weprovethefollowingtheorem:foranypositiveintegerNandT∈B(H1,H2)withaclosedrange,thereexistsanouterinverseT#NwithfiniterankNsuchthatT+y=liraT#Nyforanyy∈H2,whereT+N→∞denotestheMoore-PenroseinverseofT.ThuscomputingT+isreducedtocomputingouterinversesT#NwithfiniterankN.Moreover,becauseofthestabilityofboundedouterinverseofaT∈B(H1,H2),thisisveryuseful.
简介:1IntroductionForann×nmatrixAwhichisaninverseM-matrix,M.Neumannin[1]conjecturedthattheHadamardproductA·AisaninverseofanM-matrix.TheyhavecheckedhisconjecturewithoutfailureonUltrametricmatricesandinverseofMMA-matrices,Uni-pathicmatricesandtheWillongbyinverseM-matrices.Bo-YingWangetal.in[2]haveinvestigatedTriangularinverseM-matriceswhichareclosedundertheHadamardmultipli-cation.LuLinzheng,SunWeiweiandLiWenin[3]presentedamoregeneralconjecture
简介:证明0是具有可选服务的M/M/1排队模型的主算子及其共轭算子的几何重数为1的特征值,由此推出该模型的时间依赖解强收敛于该模型的稳态解.
简介:InthispaperaconnectivestudyofGould'sannihilationcoefficientsandAbel-Gontscharoffpolynomialsispresented.ItisshownthatGould'sannihilationcoefficientsandAbel-Gontscharoffpolynomialsareactuallyequivalenttoeachotherundercertainlinearsubstitutionsforthevariables.Moreover,apairofrelatedexpansionformulasinvolvingGontscharoff'sremainderandanewformofitaredemonstrated,andalsoillustratedwithseveralexamples.
简介:InthispaperwestudythesolutionsandstabilityofthegeneralizedWilson’sfunctionalequation∫_Gf(xty)dμ(t)+∫_Gf(xtσ(y))dμ(t)=2f(x)g(y),x,y∈G,whereGisalocallycompactgroup,σisacontinuousinvolutionofGandμisanidempotentcomplexmeasurewithcompactsupportandwhichisσ-invariant.Weshowthat∫_Gg(xty)dμ(t)+∫_Gg(xtσ(y))dμ(t)=2g(x)g(y)iff≠0and∫_Gf(t.)dμ(t)≠0,where[∫_Gf(t.)dμ(t)](x)=∫_Gf(tx)dμ(t).WealsostudysomestabilitytheoremsofthatequationandweestablishthestabilityonnoncommutativegroupsoftheclassicalWilson’sfunctionalequationf(xy)+χ(y)f(xσ(y))=2f(x)g(y)x,y∈G,whereχisaunitarycharacterofG.
简介:ABanachspaceoperatorsatisfiesgeneralizedRakoevi'sproperty(gw)ifthecomplementofitsuppersemiB-WeylspectruminitsapproximatepointspectrumisthesetofeigenvaluesofTwhichareisolatedinthespectrumofT.Inthisnote,wecharacterizehypecyclicandsupercyclicoperatorssatisfyingtheproperty(gw).