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136 个结果
  • 简介:AMarkovianriskprocessisconsideredinthispaper,whichisthegener-alizationoftheclassicalriskmodel.ItisproperthatariskprocesswithlargeclaimsismodelledastheMarkovianriskmodel.Insuchamodel,theoccurrenceofclaimsisdescribedbyapointprocess{N(t)}_(t≥0)withN(t)beingthenumberofjumpsduringtheinterval(0,t]foraMarkovjumpprocess.TheruinprobabilityΨ(u)ofacompanyfacingsuchariskmodelismainlystudied.AnintegralequationsatisfiedbytheruinprobabilityfunctionΨ(u)isobtainedandtheboundsfortheconvergencerateoftheruinprobabilityΨ(u)aregivenbyusingageneralizedrenewaltechniquedevelopedinthepaper.

  • 标签: 风险程序 马尔可夫过程 方程式 解题方法
  • 简介:增加的人口和单个财富为精力和原料资源以及为鉴于资源的有效使用,处理技术并且在生产避免排出物并且再循环过程的稳定的改进导致了一个更高的要求。Presentsituation和再循环处理的未来趋势被例子从铝和钢工业讨论,汽车和消费者以后的市政的恢复再循环。热力学的法律并且4E策略的更多的强烈遵守的重要性“经济”,精力,环境和教育被构画出。

  • 标签: 工业进程 再循环 环境 持续能力 球循环
  • 简介:Magnetohydrodynamicsisoneofthemajordisciplinesinsolarphysics.Vigorousmagnetohydrodynamicprocessistakingplaceinthesolarconvectionzoneandatmosphere.Itcontrolsthegeneratingandstructuringofthesolarmagneticfields,causestheaccumulationofmagneticnon-potentialenergyinthesolaratmosphereandtriggerstheexplosivemagneticenergyrelease,manifestedasviolentsolarflaresandcoronalmassejections.Nowadaysdetailedobservationsinsolarastrophysicsfromspaceandonthegroundurgeagreatneedforthestudiesofmagnetohydrodynamicsandplasmaphysicstoachievebetterunderstandingofthemechanismormechanismsofsolaractivity.Ontheotherhand,thespectacularsolaractivityalwaysservesasagreatlaboratoryofmagnetohydrodynamics.Inthisarticle,wereviewedafewkeyunresolvedproblemsinsolaractivitystudiesanddiscussedtherelevantissuesinsolarmagnetohydrodynamics.

  • 标签: 太阳活动 日冕物质抛射 等离子体物理 太阳大气 太阳物理学 天体物理学
  • 简介:Inthispaper,anewprocesstofabricateanelectromagneticsteppingmicromotorusingsurfacescarificiallayertechnology(SSLT)isillustrated,andtheSEMphotoofthesteppingmicromotorisshowed.Thetorqueofthesteppingmicromotorwithmaxsimumtorqueof60μNmisdirectlycalculatedbyusingelectromagneticslawsandthelawofconservationofenergy.ThestatorandtheshaftandtherotorofthemicromotorwiththematerialofnickelarefirstallfabricatedbynormalLIGAprocessatthesametime.ThesacrificiallayerstructurewiththematerialofAZresistismadeonthesurfaceoftherotorbyusingSSLT.ThestatorandtheshaftarefixedtogetherwithcoppersubstrateinsteadoftheoldTisubstratebyelectroplating.AfterremovingtheTisubstrate,PMMAresistandthesacrificiallayerstructure,therotorisseparatedfromthestatorandnewcoppersubstrate,andcanrotateonthenewsubstratedrivenbymagneticforce.Thefourcoilswith300turnseacharewoundonironbarsbyhandusingmicroscopeandsteppingmotor.Thebarsareassembledbyhandintothestatorholesfromrearofnewcoppersubstratetofromamagneticcircuitwiththestatorandtherotor.Apowersupplywithfourconsecutivepulsesprovidesthecurrentforthecoilswoundontheironbarsadnproducesthemagneticforcetodrivetherotortorunwiththespeedof60rpm.

  • 标签: LIGA 光刻 电铸 塑铸 微加工 微步进电机
  • 简介:InthispaperareversibleMarkovprocessasachemicalpolymersreactionoftwotypesofmonomersisdefined.Byanalyzingthepartitionfunctionsoftheprocessweobtainthreedifferentdistributionsoftheaveragemolecularweight,dependingofthevalueofstrengthofthefragmentationreaction,andprovethatagelationoftheprocesswilloccurinthethermodynamiclimit.

  • 标签: 可逆Markov过程 聚合反应 冻结 平稳分布 分拆函数
  • 简介:SinceitserliestyearsofR&D[1],theGEANT4simulationtoolkithasbeendevelopedfollowingsoftwareprocessstandardswhichdictatedtheoverallevolutionoftheproject.Thecomplexityofthesoftwareinvolved,thewideareasofapplicationofthesoftwareproduct,thehugeamountofcodeandCategorycomplexity,thesizeanddistributednatureoftheCollaborationitselfareallingredientswhichinvolveandcorrelatetogetherawidevarietyofsoftwareprocesses.Althoughin"production"andavailabletothepublicsinceDecember1998,theGEANT4softwareproduct[1]includesCategoryDomainswhicharestillunderactivedevelopment.Thereforetheyrequiredifferenttreatmentalsointermsofimprovementofthedevelopmentcycle,system,testingandusersupport,ThisarticleismeanttodescribesomeofthesoftwareprocessesastheyareappliedinGEANT4forbothdevelopment,testingandmaintenanceofthesoftware.

  • 标签: GEANT4 软件处理 软件开发
  • 简介:Supernovaexplosionisapeculiarastronomicalphenomenon,whichhasarousedgreatinterestandextensiveresearchbyastronomers.Atpresent,however,itiserroneouslybelievedthatthesupernovaexplosionisasplendidfuneralofadyingstar.Infact,newastronomicalobservationsandtheauthor’stheoreticalstudieshaveshownthatintheprocessofastar’snever-endingevolution,numeroussupernovaexplosionsmayoccur,andsupernovaexplosionwillrunthroughmanystagesofstellarevolution.Whenevertheatmosphereofthestarbecomesverydenseanditssurfaceiscoveredwithathicklayerofmaterialagain,athermonuclearreactioncanbeignitedagain,causingasupernovaexplosion.Especially,whenthestarhasundergoneanumberofsupernovaeexplosionsanditssurfaceiscoveredwithmultiplelayersofsupernovaexplosionremnants,thecoreofthemassivestarmayundergosuddengravitationalcollapse,causingaviolentsupernova;whenastarisimpactedbyafallingcelestialbody,italsoproducesviolentsupernovaexplosions.

  • 标签: STELLAR EVOLUTION GALAXY SUPERNOVA explosions
  • 简介:Theelectrochemicalreductionbehaviorofbilirubin(BR)atplatinumelectrodeinDMFwasinvestigatedbycyclicvoltammetry,insituelectronspinresonancespectroscopyandinsiturapidscanningthinlayerspectroelectrochemistry.ExperimentalresultsrevealedthatthereductionofBRfirstlyundergoesanECEprocess:BR-+eBR-dimerize(BR)22-+e(BR)23-.Thegenerated(BR)23-canbere-oxidizedtoBRandthentopurpurin(Pu)byaseriesofoxidationprocesses:(BR)23--e(BR)22--2e2BR,BR--2eBV--2ePu.However,there-reductionreactionsofPuarenotthereverseprocesses.Thedifferentreductionmechanismsarediscussedindetail.

  • 标签: BILIRUBIN BILIVERDIN purpurin SPECTROELECTROCHEMISTRY BIOELECTROCHEMISTRY
  • 简介:Ultrasound(US)-inducedcavitationisaneffectivewayinoxidizingorganiccontaminantsinwastewatereitherastheindependentoperationunitorincombinationwithotheroxidationmethods.Inthispaper,blackliquorandfiltrateafteracidifyingandsettlingweresonicated.Theeffectofworkingparametersonultrasonicdegradationofblackliquor,suchasdifferentcombinationmethods,frequency,powersupply,initialconcentration,pH,durationtime,ionicstrengthandcatalystwerestudied.Theresultswereasfollows:(1)Attheconditionsof40kHz,100W,4h,pHat6andtemperature30±2℃,utilizingUS/US-H2O2/US-Fenton,weak-orangefiltrateturnedtocolloidwiththeincreaseoftimeandlittlesedimentproducedaftersettling.EspeciallyfiltratecametobemilkwhitecollidesandupperwaterapproachedtonearlyachromaticbyUS-Fenton.ComparedwiththeUS,US-H2O2/US-FentonCOD(Chemicaloxidationdemand)removalratiocanincrease15%,30%respectively.Becauseofmorehydroxylradicalsproducedinthereactionprocess;(2)Attheconditionof100Wand4h,thedegradationefficiencyofblackliquorwasbetterat40kHzoverat20kHz.Moreoverblackliquorcanbebiodegradedeasily.Thosebasedonthatthebigmoleculeofcontaminantsinaqueoussolutioncanbechangedintothelittlemoleculewithultrasound(3)Attheconditionof40kHzand4h,theCODremovalratioofblackliquorwasmorehigherat60Wthanat80W,whiletheremovalratioofCODat60Wwasnearlyclosetotheratioat100W;(4)Theinitialconcentrationofblackliquorinfluencedtheeffectofsonochemicaldegradation;(5)ThevariationofpHhadnoeffectondegradation;(6)Thelongerthedurationtime,thegreatertheremovalratioofCOD.Butthisratioincreasedslowlyafter4h;(7)Adding0.2g/LNaCltochangetheionicstrengthoftheblackliquor,theCODremovalratiocanincrease10%;(8)ThedegradationratesincreasedbythecoexistentcatalystsofTiO2,Co2+andAg+.

  • 标签: 降解反应 超声辐射 有机污染物 废水处理 黑色液体 化学需氧量
  • 简介:OneofthemostchallengingissuesfacedinHEPinrecentyearsisthequestionofhowtocapitaliseonsoftwaredevelopmentandmaintenanceexperienceinacontinuousmanner.Tocapitaliseinourcontextmeanstoevaluateandapplynewtechnologiesastheyarise,andtofurtherevolvetechnologiesarlreadywidelyinuse,Italsoimpliesthedefinitionandadoptionofstandards,whileensuringreproducibilityandqualityofresults.TheCMSprocessimprovementeffortistwo-pronged.ItaimsatcontinuousimprovementofthewayswedoObjectOrientedsoftware,aswellascontinuousimprovementintheefficiencyoftheworkingenviuronment.Inparticulartheuseandcreationofde-factosoftwareprocessstandardswithinCMShasproventobekeytooursuccessfulsoftwareprocessimprovementprogram.WedescribethesuccessfulCMSimplementationofasoftwareprocessimprovementstrategy,followingISO15504sincethreeyears.WegivethecurrentstatusofthemostimportantprocessesfamiliesformallyestablishedinCMS,andprovidetheguidelineswefollowedbothfortooldevelopment,andmethodologyestablishment.

  • 标签: 高能物理学 软件开发 软件处理
  • 简介:Inordertounderstandthebreakupperformanceofcoaxialporousinjectors,thespraysofcoaxialporousinjectorswithtwodifferentporousmaterialcylinderlengthswerecomparedwiththoseofconventionalshearcoaxialinjectors.Toallowcomparison,thewallinjectionlengthsweredesignedtobeequivalenttothevalueoftherecessdepth.Coldflowsprayswerevisualizedusingback-litphotographymethodsandanalyzedquantitativelywithalaserdiffractionapparatus,inordertostudytheeffectsofthemomentumfluxratioandWebernumberonthebreakupforeachtypeofinjector.Incaseoftheshearcoaxialinjector,thelargeliquidcorewasobservedinlowairmassflowratecondition.However,thedestabilizationoftheliquidjetfromthecoaxialporousinjectorisalmostcompletewithintheinnerregion,neartheinjectorfaceplate.Additionally,betterbreakupperformanceinlowgasflowrateconditionwasobtainedwhentheporouscylinderlengthdecreased,whiletheshearcoaxialinjectorsshowedbetterbreakupefficiencywhentherecesslengthincreased.Inconclusion,thedifferentbreakupprocesscausedbytheradialmomentumintheinnerregionoftheporousinjectordisintegratedtheliquidcore.

  • 标签: 多孔喷嘴 同轴 性能 破碎效率 崩解 喷油器
  • 简介:Acetonediffusioninpolycarbonatewasinvestigatedbyspin-echo1HNMRimagingmethodatroomtemperature.TheresultshowsthatthediffusionprocesssatisfiesCaseⅡdiffusion.Thevelocityofdiffusionfrontis13.8nmsec-1(0.05mm/h).

  • 标签: NM R IMAGING DIFFUSION Polycarbonate/Acetone
  • 简介:Thedefinitionsandpurposesofenergysystemsandprocesssystemsarecomparedinthispaperbyconsideringtheroleofenergyinsystemswithemphasisonthedifferencesinthemethodsusedtooptimizetheexergoeconomicbenefitsofbothtypesofsystems.TheprocesssystemexergoeconomicrelationshipprimarilyincludetheestablishmentoftheThree-linkmodelofprocesssystems,thecompositionofobjectivefunctions,andthecorrespondingboundaryconstraintconditionsforoptimization.TheThree-Link-Method(TLM)whichisbasedonexergoeconomics,canbeusedtoeffectivelyoptimizeprocesssystems.TheTLMusedtooptimizeprocesssystemsisoutlinedinthispaper,Someaspectswhichneedfurtherdevelopmentarealsoidentified.

  • 标签: 热能经济 过程系统 优化分析
  • 简介:Theeffectofresinstructureondesalinationofligninsolutionwasinvestigated,theoptimalstructureofresinisasfollows;crosslinkingdegreeas4%,ratioofcationogentoanionogenisnear1.withsuchresinthedesalinationofligninwasproducedverywellbecausetheresinhasbothmoleculesievingandionretardationproperties.Thesulfonationdegressofligninandtotalsaltcontentofligninsolutionweredeterminredwithionexchangetechnique,therelativeerrorlessthan1%.Thesaltcontentofsmallmoleculeintheligninsolutionwascalculatedfromsulfonationdegreeofligninandtotalsalt.Amonggelandmacroporousresinsthebestseparationofligninfromreducingsugarwasachievedwithinterpenetratingsulfonatedresin2×1.5×1.Theseparationofligninwithinterpenetratingresinwascarriedoutsimultaneouslywithfractionationoflignin,theeffectoffractionationwithmacroporoussulfonatedresinisbetterthanthatwithinterpenetratingresin,buttheformerhasadefinitesorptionofligninwhichdecreasedtherecoveryoflignin.

  • 标签: 木质素分离 木质素提纯 离子交换过程