简介:Thinfilmsofpolymerblendscomposedofalternatingcopolymer,diblockcopolymerand/orhomopolymerarestudiedusingMonteCarlosimulation.Amultilayermorphologyisobservedinthefilm,thatis,theblendedpolymersassembleintoindividualdomainsarrangedfrominteriortothesurfacesofthefilm.Thecoexistingcomponentsresidingthroughouttheneighboringdomainsinthefilmmakenodistinguishableinterfacebetweenanyneighboringdomains.Bythismeans,itformsaverticalcompositiongradientinthepolymericfilm.Beingdifferentfromlayer-by-layerdepositionofpolyelectrolyteorhydrogenbondingapproachetc.,thelayeredstructureinthisstudyisformedbypolymerblendinginonestep.Alternatingcopolymersarefoundtobeessentialcomponentstoformverticalcompositiongradient(layeredstructure)inthinfilms.
简介:StdHepC++[1]isaCLHEP[2]MonteCarloeventclasslibrarywhichprovidesacommoninterfacetoMonteCarloEventGenerators,ThisworkisanextensiveredesignoftheStdHepFortraninterfacetousethefullpowerofobjectorienteddesign,AgeneratedeventmapsnaturallyontotheDirectedAcyclicGraphconceptandwehaveusedtheHepMCclassestoimplementthis.Thefullimplementationallowstheusertocombineeventstosimulatebeampileupandaccessthemtransparentlyasthoughtheywereasingleevent.
简介:Basedonthepreparativeexperimentsofthelight-emittingdiode(LED)encapsulant,threetypesofmonomermodelswithdifferentfunctionalgroupsarecarriedouttostudythepolymerizationprocessbydynamicMonteCarlo(DMC)simulationandbondfluctuationmodel(BFM).Wecalculatethedegreeofpolymerization,theradiusofgyrationandthefrequencyofvoidspherestodiscussthepolymerizationprocess,themolecularsizeandthespatialdistributionatdifferentvolumefractionsandproportions.OurresultsareinagreementwithGrest'sdecayrateandFlory'sscalelaw.Simulationsshowthatthepolymerizationprocessdependsontheappropriatevolumefractionandproportionexceedingly,andthevolumecontractioninthepolymerizationprocesscanalsobeobservedinthisstudy.Theseinvestigationscouldprovidesomeinsightsintotheunderstandingofthepolymerizationprocessoftheencapsulantandhelpustoadjusttheparametersinlaterexperiments.
简介:TheMonte-CarloArrayProcessor(MAP)hasbeendesignedusingcommodityofftheshelf(COTS)itemstoprovidetheCPUrequirementsoffulleventsimulationfortheLHCexperiments.Thesolutionishowevercompletelygeneral,soandCPUintensiveapplicationwithlimitedinputrequirementscanberunonthesystem.Operatingcontrolsoftwarehasbeenwrittentomanagethedataflowoiverthe100BaseTethernetconnectingthe300nodes(400MHzPII's)tothe6mastercontrolnodes700MHzPIII'seachwith500Gbofdisk),Upgradeto1000nodesisplkanned.Jobcontrolsoftwarethatallowstheusertorunthesamejobonallnodes,whilstallowingforsmalldifferencesininitialisationparametersbetweennodeshasalsobeenwritten.GMAPistheGRIDawareMAPcontrolsoftware,Thisallowsremotejobpreparationandsubmissionusingglobustoolkitforauthentificationandcommunication.ThesoftwarewillbeavailableandopensthepossibilityfordoingmassiveMonteCarloproductionoverseveralremoteMAPsitessimultaneously.
简介:Tosharpentheimagingofstructures,itisvitaltodevelopaconvenientandefficientquantitativealgorithmoftheopticalcoherencetomography(OCT)sampling.InthispaperanewMonteCarlomodelissetupandhowlightpropagatesinbio-tissueisanalyzedinvirtueofmathematicsandphysicsequations.Therelations,inwhichlightintensityofClassIandClass2lightwithdifferentwavelengthschangeswiththeirpermeationdepth,andinwhichClassIlightintensity(signallightintensity)changeswiththeprobingdepth,andinwhichangularlyresolveddiffusereflectanceanddiffusetransmittancechangewiththeexitingangle,arestudied.TheresultsshowthatMonteCarlosimulationresultsareconsistentwiththetheorydata.
简介:ThefundamentalelemetsoftheLHCbMonteCarloproductionsystemaredescribed,coveringsecurity,Jobsubmission,execution,datahandlingandbookkeeping,AnanalysisisgivenofthemainrequirementsforGRIDfacilities,togetherwithsomediscussionastohowtheGRIDcanenhancethissystem.AsummaryisgivenofthefirstexperiencesinmovingthesystemtoaGRIDenvironment.ThefirstplanningforinterfacingtheLHCbOOframeworktoGRIDservicesisoutlined.
简介:Thispaperintroducestwokindsofmethodswithhighaccuracyforfi-niteelementprobabilitycomputingmethod,bywhichthefunctionvalueononeorafewnodescanbecalculatedwithoutformingthetotalstiffnessmatrix.
简介:Reconstructionofabsorptioncoefficientμ_aandscatteringcoefficientμ_aisveryimportantforapplicationsofdiffuseopticaltomographyandnearinfraredspectroscopy.Aimingattheearlycancerdetectionofcervixandstomach,wepresentafastinverseMonte-Carloschemeforextractingμ_aandμ_sofatubulartissuefromthemeasurementonfrequencydomain.Resultsshowthatthecomputationtimeforreconstructingonesetofμ_aandμ_sislessthan1minandtherelativeerrorsinreconstructionarelessthan±10%fortheopticalpropertiesofnormalcervicaltissueandprecancerouslesions.
简介:Thestochasticmodelsoftheusualjointsarefirstestablishedthroughintro-ducingtheconceptsof“clearancecharacteristicelement”and“clearancespace”.Afterde-rivingtheprobabilitydensityfunctionofthejointclearanceandmakingtheprobabilisticanalysisoftheresultedkinematicerrors,thesamplingformulasoftheindependentvaria-blesofthejointclearancesarefurtherdeduced.ThroughMonteCarlosimulation,thesta-tisticalcharacteristicsandfrequencyhistogramsofthekinematicerrorsarethenanalysedoncomputer.
简介:Inthispaperweproposedanovelexactfixed-nodequantumMonteCarlo(EFNQMC)algorithm,whichisaself-optimizingandself-improvingprocedure,IncontrasttothepreviousEFNQMCmethod,thetrialfunctionisoptimizedsynchronisticallyinthediffusionprocedure,butnotbeforethebeginningofEFNQMCcomputation.Inordertooptimizethetrialfunction,theimprovedsteepestdescenttechniqueisused,inwhichthestepsizeisautomaticallyadjustable.Theprocedureisquasi-Newtonandconvergessuperlinearly.Wealsouseanoveltrialfunction,whichhascorrectelectron-electronandelectron-nucleuscuspconditions.ThenovelEFNQMCalgorithmandthenoveltrialfunctionareemployedtocalculatetheenergiesof1^1A1stateofCH2,^1AgstateofC8andtheground-statesofH2,LiH,Li2,H2O,respectively.Thetestresultsshowthatboththenovelalgorithmandthetrialfunctionproposedinthepresentpaperareveryexcellent.
简介:对核参数敏感度和不确定性分析的理论方法进行了探讨,在敏感度系数的基础上所定义的积分指标Esum能定量地表示出两个不同核裂变装置的相似性,即可用于定量地比较一个基准核裂变实验装置与一个欲评估核裂变装置的相似程度。不确定性的分析提供了一个计算核裂变系统中由于截面数据方差而导致系统中七疆方差的方法,并且也提供了一个计算不同核裂变系统中Keff协方差的方法。不确定性的分析方法是将截面数据的方差信息通过与能量有关的敏感度系数传播给Keff行。某一材料截面数据的方差可以传播给所有含有该材料的临界装置。有着相同材料的临界装置将产生关联。