简介:WepresentthepreliminaryresultsofourcodeOPAQS(opacitycalculationusingquantumstatisticalmodel)thatisbasedontheselfconsistentHartree-Fock-Slatermodelfortheaverageatom.Thecodeiscapableofperformingrobustcalculationsofaveragechargestate,frequency-dependentandmeanopacities.Theaccuracyoftheatomicmodelisverifiedbycomparingthecalculationsofaveragechargestatewithvariouspublishedresults.ThemonochromaticopacitiesforironcomputedatdifferentsetsoftemperaturesanddensitiesarecomparedwithLEDCOP.TheRosselandandPlanckopacitiesforironandaluminumarevalidatedwithsomestate-of-the-artcodes.Theresultsareingoodagreementwiththepublisheddata.
简介:SinceGibbssynthesizedageneralequilibriumstatisticalensembletheory,manytheoristshaveattemptedtogeneralizedtheGibbsiantheorytonon-equilibriumphenomenadomain,howeverthestatusofthetheoryofnon-equilibriumphenomenacannotbesaidasfirmaswellestablishedastheGibbsianensembletheory.Inthiswork,wepresentaframeworkforthenon-equilibriumstatisticalensembleformalismbasedonasubdynamickineticequation(SKE)rootedfromtheBrussels-Austinschoolandfollowedbysomeup-to-dateworks.TheconstructedkeyistouseasimilaritytransformationbetweenGibbsianensemblesformalismbasedonLiouvilleequationandthesubdynamicensembleformalismbasedontheSKE.Usingthisformalism,westudythespin-Bosonsystem,ascasesofweakcouplingorstronglycoupling,andobtainthereduceddensityoperatorsfortheCanonicalensembleseasily.
简介:Clustering,asapowerfuldataminingtechniquefordiscoveringinterestingdatadistributionsandpatternsintheunderlyingdatabase,isusedinmanyfields,suchasstatisticaldataanalysis,patternrecognition,imageprocessing,andotherbusinessapplications.Density-basedSpatialClusteringofApplicationswithNoise(DBSCAN)(Esteretal.,1996)isagoodperformanceclusteringmethodfordealingwithspatialdataalthoughitleavesmanyproblemstobesolved.Forexample,DBSCANrequiresanecessaryuser-specifiedthresholdwhileitscomputationisextremelytime-consumingbycurrentmethodsuchasOPTICS,etc.(Ankerstetal.,1999),andtheperformanceofDBSCANunderdifferentnormshasyettobeexamined.Inthispaper,wefirstdevelopedamethodbasedonstatisticalinformationofdistancespaceindatabasetodeterminethenecessarythreshold.ThenourexaminationoftheDBSCANperformanceunderdifferentnormsshowedthattherewasdeterminablerelationbetweenthem.Finally,weusedtwoartificialdatabasestoverifytheeffectivenessandefficiencyoftheproposedmethods.
简介:TheentanglemententropyofanacousticblackholeinaBose–Einsteincondensates(BEC)isderived,whichisassociatedwiththephononsgeneratedviatheHawkingmechanisminasonichole.ConsideringthedispersionrelationofaBEC,werecalculatetheentanglemententropyoftheacousticblackholebymeansofstatisticalmethodintwolimits.Wefindthattheentropyisstillproportionaltotheareaofeventhorizon,butwithacoefcientdependentontheinfraredcutof.
简介:Atmosphericconcentrationsofpolycyclicaromatichydrocarbons(PAHs)weremeasuredduringvariousseasonsatsixdifferentcities/locationsinQingdaoalongshore.TheannualaveragePAHsconcentrationrangedfrom16ng/m3(atacleancom-paredsite)to308ng/m3(inanindustrysite).TheaveragetotalparticulatePAHsconcentrationwas74.5ng/m3withahigherconcentrationofparticulatePAHsinwinter.Basedonayear-rounddataset,thesourcesofPAHsintheairofQingdaoweredrawnbyprincipalfactoranalysisandcorrelationanalysis.TheresultsindicatedthatvehicleemissionsandoilburningwerethemainsourceofPAHsinQingdaoalongshore.
简介:Effect of Langevin Statistical Fluctuations on Heavy-ion Induced Fusion ReactionEffectofLangevinStatisticalFluctuationsonHeav...
简介:ThegoalofthisstudyistoanalyzethestatisticsofthebackscattersignalfrombovinecancellousboneusingaNakagamimodelandtoevaluatethefeasibilityofNakagami-modelparametersforcancellousbonecharacterization.Ultrasonicbackscattermeasurementswereperformedon24bovinecancellousbonespecimensinvitroandthebackscattersignalswerecompensatedforthefrequency-dependentattenuationpriortotheenvelopedetection.ThestatisticsofthebackscatterenvelopeweremodeledusingtheNakagamidistribution.Ourresultsrevealthatthebackscatterenvelopemainlyfollowedpre-Rayleighdistributions,andthedeviationsofthebackscatterenvelopefromRayleighdistributiondecreasedwithincreasingbonedensity.TheNakagamishapeparameter(i.e.,m)wassignificantlycorrelatedwithbonedensities(R=0.78–0.81,p<0.001)andtrabecularmicrostructures(|R|=0.46–0.78,p<0.05).Thescaleparameter(i.e.,?)andsignal-to-noiseratio(SNR)alsoyieldedsignificantcorrelationswithbonedensityandstructuralfeatures.Multiplelinearregressionsshowedthatbonevolumefraction(BV/TV)wasthemainpredictoroftheNakagamiparameters,andmicrostructureproducedsignificantlyindependentcontributiontothepredictionofNakagamidistributionparameters,explaininganadditional10.2%ofthevarianceatmost.TheinvitrostudyshowedthatstatisticalparametersderivedwithNakagamimodelmightbeusefulforcancellousbonecharacterization,andstatisticalanalysishaspotentialforultrasonicbackscatterboneevaluation.
简介:Inrealmultiple-inputmultiple-output(MIMO)systems,theperfectchannelstateinformation(CSI)maybecostlyorimpossibletoacquire.Butthechannelstatisticalinformationcanbeconsideredrelativelystationaryduringlong-termtransmission.Thestatisticalinformationcanbeobtainedatthereceiverandfedbacktothetransmitteranddonotrequirefrequentupdate.Byexploitingchannelmeanandcovarianceinformationatthetransmittersimultaneously,thispaperinvestigatestheoptimaltrans-missionstrategyforspatiallycorrelatedMIMOchannels.Anupperboundofergodiccapacityisderivedandtakenastheper-formancecriterion.Simulationresultsarealsogiventoshowtheperformanceimprovementoftheoptimaltransmissionstrategy.
简介:Weconstructanewtypeofphoton-addedsqueezedcoherentstategeneratedbyrepeatedlyoperatingthebosoniccreationoperatoronanewtypeofsqueezedcoherentstate[FanHYandXiaoM1996Phys.Lett.A22081].Wefindthatitsnormalizationfactorisrelatedtosingle-variableHermitepolynomials.Furthermore,weinvestigateitsstatisticalproperties,suchasMandel’sQparameter,photon-numberdistribution,andWignerfunction.Thenonclassicalityisdisplayedintermsoftheintenseoscillationofphoton-numberdistributionandthenegativityoftheWignerfunction.
简介:Statistical Threefold nagmentation in 25 MeV/u 40Ar Induced ReactionsStatisticalThreefoldnagmentationin25MeV/u40ArInduce...
简介:UsingtheFourierhelicaldecomposition,weobtaintheabsolutestatisticalequilibriumspectraofleft-andright-handedhelicalmodesintheincompressibleidealHallmagnetohydrodynamics(MHD).Itisshownthattheleft-handedhelicalmodesplayamajorroleonthespectraltransferpropertiesofturbulencewhenthegeneralizedhelieityandmagnetichelieityarebothpositive.Incontrast,theright-handedhelicalmodeswillplayamajorrolewhenbotharenegative.Furthermore,wealsofindthatifthegeneralizedhelieityandmagnetichelicityhaveoppositesigns,thetendencyofequilibriumspectratocondenseatthelargeorsmallwavenumberswillbepresentedindifferenthelicalsectors.ThisindicatesthatthegenerMizedhelicitydominatestheforwardcascadeandthemagnetichelicitydominatestheinversecascadepropertiesoftheHallMHDturbulence.
简介:在这篇论文,有它比1大的参数的Chebyshev方程的答案被获得。解决方案的衍生物的起始的值是磁化的表达式,它为任何旋转量数字S是有效的。Chebyshev方程从当我们应付了海森堡模型时,获得的一个平常的微分方程被转变,以便计算磁化的所有三个部件,由许多身体格林在随机的阶段近似下面的功能。Chebyshev与比1被讨论大的争论工作。有他们比1大的参数的Chebyshev多项式有的这论文hows他们的物理申请。
简介:Thispaperdiscussesastatisticalsecond-ordertwo-scale(SSOTS)analysisandcomputationforaheatconductionproblemwitharadiationboundaryconditioninrandomporousmaterials.Firstly,themicroscopicconfigurationforthestructurewithrandomdistributionisbrieflycharacterized.Secondly,theSSOTSformulaeforcomputingtheheattransferproblemarederivedsuccessivelybymeansoftheconstructionwayforeachcell.Then,thestatisticalpredictionalgorithmbasedontheproposedtwo-scalemodelisdescribedindetail.Finally,somenumericalexperimentsareproposed,whichshowthattheSSOTSmethoddevelopedinthispaperiseffectiveforpredictingtheheattransferperformanceofporousmaterialsanddemonstratingitssignificantapplicationsinactualengineeringcomputation.
简介:The12C+13Csystemhasbeenstudiedextensively,becauseofthesimilarityoftheentrancechanneltotheastrophysicallyimportant12C+12Creaction[1??3].Untilnow,threedifferentmethodshavebeenexploitedtoperformthefusioncrosssectionmeasurementsfor12C+13CundertheCoulombbarrier:(1)measuringtheyieldofcharacteristicrays,(2)thetotal-rayyieldsusingNaIsummingdetectorsand(3)theactivityofthereactionresidue24Na(T1=2=15.0h).Recently,thefusioncrosssectionof12C+13Chasbeenmeasureddownto0.9nbthroughtheactivitymeasurementbyourgroup[4].Althoughthestatisticalmodelcalculationsinallthesethreemethodshavebeenroutinelyusedtoconverttheobservedpartialcrosssectionsintothetotalfusioncrosssections[5],thesystematicuncertaintyinducedbythestatisticalcorrectionshasnotbeenstudiedverywell.