简介：Inmostexitingportfolioselectionmodels,securityreturnsareassumedtohaverandomorfuzzydistributions.However,uncertaintiesexistinactualfinancialmarkets.Marketsareassociatednotonlywithinherentrisk,butalsowithbackgroundriskthatresultsfromthedifferencesamongindividualinvestors.Thispaperinvestigatedthecomplianceofstockyieldstothefuzzy-naturedhigh-ordermomentsofrandomnumbersinordertodevelopahigh-momenttrapezoidalfuzzyrandomportfolioriskmodelbasedonvariance,skewness,andkurtosis.DataobtainedfromtheShanghaiStockExchangeandShenzhenStockExchangewasusedtoassesstheinfluenceontheproposedmodelofbothbackgroundriskandthemaximumlevelofsatisfactionoftheportfolio.Theempiricalresultsdemonstratedthatthedifferencesbetweenthemaximumandminimumvariance,skewness,andkurtosisvaluesoftheportfoliowerepositivelycorrelatedwiththevarianceofthebackgroundrisk.

简介：Objective:ToevaluateHighResolutionComputerTomography(HRCT)inthediagnosisofexternalearcanalcholesteatoma.Methods:Inthisretrospectivestudy,HRCTsof27patientswithexternalearcanalcholesteatomawerereviewed.Thechangesintheexternalearcanal,tympanicmembrane(TM),scutum,tympanumandmastoidweremeasuredandcategorized.Results:Fourteenpatientsshowednoormilddestructionintheexternalearcanal(stageIgroup).Eightpatientshadobviousenlargementintheexternalearcanal(stageIIgroup)butshowedlimiteddestructionsofthemastoidboneandnodamageofthetympanums.Fivepatientshadseriousdestructionofthemastoidboneanddamageofthetympanum(stageIIIgroup).AllpatientsinthestageIIIgroupshowedacompressionofmanubriumsandTMs,with3havingdamagesonossicularchain.BonedestructionoftheverticalsectionoffacialnervecanalwasdiscoveredinonecaseinthestageIIIgroup.Conclusion:HRCTcanprovidedetailinformationabouttheextentofexternalearcanalcholesteatoma.Suchinformationcanbeusedtoidentifyspecialsituationswithseriouscomplicationsandtodifferentiateexternalearcanalcholesteatomafrommiddleearcholesteatoma.

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简介：Transitionmetal-dopingcouldeffectivelyextendthelightresponserangeofTiO2photocatalystsfromtheultraviolet(UV)tothevisibleregion.Co-dopedbrookitetitaniumdioxide(Co–TiO2)photocatalystsweresynthesizedviathehydrothermalmethodwithtitaniumtetrachlorideastherawmaterialandcobaltchloridehexahydrateasthedopant.ThepreparedCo–TiO2photocatalystswerecharacterizedbyX-raydiffraction(XRD),scanningelectronmicroscopy(SEM),transmissionelectronmicroscopy(TEM),Ramanspectroscopy,X-rayphotoelectronspectroscopy(XPS)andUV–Visdiffusereflectancespectroscopy(UV–VisDRS).ThephotocatalyticactivitiesofCo–TiO2photocatalystswereevaluatedbyphotocatalyticdegradationofisopropanolalcohol(IPA),atypicalvolatileorganiccompound(VOC),undervisiblelight.TheinfluencesofdifferentCodopingrates,initialconcentrationsofIPAgasandtheamountsofphotocatalystadditionwerealsostudied.Atthesametime,theenhancementmechanismofcobaltionsasatrapforphotogeneratedholeswasdiscussed.Thus,wefoundtheoptimumdopingrate,initialconcentrationofIPAgasandamountofphotocatalysttoadd.TheresultsshowthatthemesoporousCo–TiO2photocatalystspossesssmallersizeparticles,largerspecificsurfacearea,lowerforbiddenbandgapenergy(Eg)andbetterphotocatalyticactivitythanpurebrookiteTiO2.WhenthedopingofCowas7%bymass,theinitialconcentrationofIPAgaswas1.0×10?6mol/LandtheadditionofCo–TiO2photocatalystswas50mg,thebestphotocatalyticactivitywasachieved.Furthermore,thedegradationrateofIPAwasupto91%,whichshowsgreatpotentialforwastewatertreatment.

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简介：LatticeBoltzmannmethodisoneofthewidelyusedinmultiphasefluidflow.However,thetwomaindisadvantagesofthismethodaretheinstabilityofnumericalcalculationsduetothelargedensityratiooftwophasesandimpossibilityofthetemperaturedistributiontobefedbackintothevelocitydistributionfunctionwhenthetemperatureissimulated.BasedonthecombinationprescribedbyInamuro,thelargedensityratiotwo-phaseflowmodelandthermalmodelmakesthedensityratioofthemodelsimulationtobeincreasedto2778:1byoptimizingtheinterfacedistributionfunctionoftwo-phasewhichimprovestheaccuracyofdifferentialformat.Thephasetransitiontermisaddedassourcetermintothedistributionfunctioncontrollingtwophaseorderparameterstodescribethetemperatureeffectonthegas-liquidphasetransition.Thelatentheatgeneratedfromthephasechangeisalsoaddedasasourcetermintothetemperaturedistributionfunctionwhichsimulatesthemovementoftheflowunderthecommoncouplingofdensity,velocity,pressureandtemperature.Thedensityandthetemperaturedistributionofsinglebubblearesimulated.Comparisonofthesimulationresultswithexperimentalresultsindicatesagoodagreementpointingouttheeffectivenessoftheimprovedmodel.

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简介：ThelatestUSplanthatincludesrare-earthmetalsonits$200billiontarifflistwillraisecostsforAmericanbuyersandmayevenforceChinatofasttrackdevelopmentofitsownhigh-techapplicationssuchasmotorsforsuchmetalsinafewyears,analystssaid.