简介:Thispaperconstructedportfoliosaccordingtothegrowthratesandtheirstabilityoffirm'stotalstockholders'equitypershareandnetincomepershare,usingallthefirms'informationofShanghaiA-sharemarket.Wefoundthatthemarketexhibitssomeoverreactiontothegrowthraieoffirm'snetincomepershare,andisn'tsensitivetothestabilityoffirm'sgrowthrates.
简介:ANEFFICINTIMPLEMENTATIONOFMERRILL'SMETHODYANGBing(DepartmentofManagementEngineeringHarbinEngineeringUniversityHarbin150001)Ab...
简介:Let■Ω=Γ=Γ1+Γ2(seeFig.1),meas(Γ1)>0,V={v|v∈H1(Ω),v|Γ1=0},andV0={ω|Δω=hinΩ,ω|Γ=0,(?)h∈V}.LetV0′=thedualspaceofV0,a(u,v)=∫Ω▽u·▽Δvdx,andF(v)=∫Ωfvdx+∫Γ2g1Δvds-∫Γg2(?)ds,f∈V′0,g1∈H-(1/2)(Γ2),g2∈H-(3/2)(Γ).Considerthevariationalproblem:findu∈Vsuchthata(u,v)=F(v),(?)v∈V0.(1)UsingTartar’slemma,weprovethatforproblem(1)thereexistsauniqueu∈Vsatisfying■
简介:Inthiseraofadata-drivensociety,usefuldata(BigData)isoftenunintentionallyignoredduetolackofconvenienttoolsandexpensivesoftware.Forexample,weblogfilescanbeusedtoidentifyexplicitinformationofbrowsingpatternswhenusersaccesswebsites.Somehiddeninformation,however,cannotbedirectlyderivedfromthelogfiles.Wemayneedexternalresourcestodiscovermoreknowledgefrombrowsingpatterns.Thepurposeofthisstudyistoinvestigatetheapplicationofwebusageminingbasedonweblogfiles.Theoutcomeofthisstudysetsfurtherdirectionsofthisinvestigationonwhatandhowimplicitinformationembeddedinlogfilescanbeefficientlyandeffectivelyextracted.Furtherworkinvolvescombiningtheuseofsocialmediadatatoimprovebusinessdecisionquality.
简介:WU-RITT'SMETHODFORNONLINEARCONTROLSYSTEMS¥LIShurong(InstituteofSystemsScience,AcademiaSinica,Beijing100080,China)Abstract:Thi...
简介:TheanalysisandevaluationofanactualportsystemcontainingRdifferentship’skindsandNsubsystemseachofwhichconsistsofM.(i=1,2,…,N)portsarederived.TheexternalarrivalsofshipstothesystemcomefromRdifferentPoissonsourcesandtheinterarrivalstothequeueofeachportofasubsystemaredeterminedaccordingtoconditionprobabilities.EachporthasmultipleberthswhoseservicetimesaredistributedaccordingtoErlangprobabilitydistributionfunctions.EachportofasubsystemhasRinfinitecapacitybuffersforstoringshipsinterarrived.Thismethodprovidesagoodapproximationprocedureforobtainingsystemperfor-mancemeasuressuchaswaitingtimesofships,averagequeuelengths,etc.Optimumportcapacitycanthusbeevaluatedbyusingthisanalysis.Asimulationisalsopresentedtotestthisapproximateanalysis,andagoodagreementisobserved.Thismodelshallbeusedintheplanningofseveralactualportsystems.Throughtheapplicationofthismodel,itispossibletoanalyzeandevaluateperformancesofthesystems.