外文翻译--不规则制造系统的动态代理人模型和说明书.doc
1附录1:翻译(英文)ModelingandspecifcationsofdynamicagentsinfractalmanufacturingsystemsKwangyeolRyua,YoungjunSonb,MooyoungJunga,*aDepartmentofIndustrialEngineering,PohangUniversityofScienceandTechnology,Pohang,SouthKoreaSystemsandIndustrialEngineeringDepartment,TheUniversityofArizona,Tucson,AZ,USAbReceived9September2002;accepted16April2003AbstractInordertorespondtoarapidlychangingmanufacturingenvironmentandmarket,manufacturingsystemsmustbeflexible,adaptable,andreusable.Thefractalmanufacturingsystem(FrMS)isoneofthenewmanufacturingparadigmsthataddresstheneedforthesecharacteristics.TheFrMSiscomprisedofanumberofbasiccomponents,eachofwhichconsistsoffivefunctionalmodules:(1)anobserver,(2)ananalyzer,(3)anorganizer,(4)aresolver,and(5)areporter.Eachofthesemodules,usingagenttechnology,autonomouslycooperatesandnegotiateswithotherswhileprocessingitsownjobs.Theresultingarchitecturehasahighdegreeofself-similarity,oneofthemaincharacteristicsofafractal.DespitethemanyconceptualadvantagesoftheFrMS,ithasnotbeensuccessfullyelaboratedandimplementedtodatebecauseofthedifficultiesinvolvedindoingso.Inthispaper,thestaticfunctionsanddynamicactivitiesofeachagentaremodeledusingtheunifiedmodelinglanguage(UML).Then,relationshipsamongagents,workingmechanismsofeachagent,andseveralfractal-specificcharacteristics(selfsimilarity,self-organization,andgoal-orientation)aremodeledusingtheUML.Then,amethodfordealingwithseveraltypesofinformationsuchasproducts,orders,andresourcesintheFrMSispresented.Finally,apreliminaryprototypefortheFrMSusingAgletsTMispresented.#2003ElsevierB.V.Allrightsreserved.Keywords:Fractalmanufacturingsystem(FrMS);Agenttechnology;UML;ModelingAbbreviations:FrMS,fractalmanufacturingsystem;BFU,basicfractalunit;DRP,dynamicrestructuringprocess;UML,uni?edmodelinglanguage;HMS,holonicmanufacturingsystem;BMS,bionic/biologicalmanufacturingsystem;CNP,contractnetprotocol;MANPro,mobileagent-basednegotiationprocess;NMA,networkmonitoringagent;EMA,equipmentmonitoringagent;SEA,scheduleevaluationagent;DRA,dispatching-ruleratingagent;RSA,real-timesimulationagent;SGA,schedulegenerationagent;GFA,goalformationagent;TGA,taskgoverningagent;NEA,negotiationagent;KDA,knowledgedatabaseagent;DMA,decision-makingagent;FSM,fractalstatusmanager;FAM,fractaladdressmanager;REA,restructuringagent;NCA,networkcommandagent;ECA,equipmentcommandagent;STA,systemagent;NTA,networkagent;MP,materialprocessor;MH,materialhandler;MT,materialtransporter;BS,bufferstorage;MRP,materialremovalprocessor;MFP,materialformingprocessor;MIP,materialinspectionprocessor;PD,passivedevice;FMH,?xedmaterialhandler;MMH,movablematerialhandler;FMT,fixedmaterialtransporter;MMT,movablematerialtransporter;ABS,activebufferstorage;PBS,passivebufferstorageE-mailaddress:myjungpostech.ac.kr(M.Jung).*Correspondingauthor.Tel.:t82-54-279-2191;fax:t82-54-279-5998.0166-3615/$seefrontmatter#2003ElsevierB.V.Allrightsreserved.doi:10.1016/S0166-3615(03)00099-X1.IntroductionFacingintensifiedcompetitioninagrowingglobalmarket,manufacturingenterpriseshavebeenreengineeringtheirproductionsystemstoachievecomputerintegratedmanufacturing(CIM).MajorgoalsofCIMinclude,butarenotnecessarilylimitedto,loweringmanufacturingcosts,rapidlyrespondingtochangingcustomerdemands,shorteninglead2times,andincreasingthequalityofproducts13.However,thedevelopmentofaCIMsystemisanincrediblycomplexactivity,andtheevolutiontoCIMhasbeenslowerthanexpected4,5.Thiscanbedirectlyattributedtohighsoftwaredevelopmentandmaintenancecosts.Therefore,inordertoachieveacompetitiveadvantageintheturbulentglobalmarket,themanufacturingenterprisemustchangemanufacturingprocessesfromallanglesincludingordering,productdesign,processplanning,production,sales,etc.AsacontrolmodelforimplementingCIMsystems,hierarchicaldecompositionofshopflooractivitieshasbeencommonlyusedintheshopfloorcontrolsystem(SFCS),thecentralpartofaCIMsystem2.Generally,acentraldatabaseprovidesaglobalviewoftheoverallsystem,andcontrollersgenerateschedulesandexecutethem.Hierarchicalcontroliseasytounderstandandislessredundantthanotherdistributedcontrolarchitecturessuchasheterarchicalcontrol.However,ithasacrucialweakpoint,whichisthatasmallchangeinonelevelmaysignificantlyandadverselyaffecttheotherlevelsinthehierarchy.Therefore,itisnormallysaidthathierarchicalcontrolofCIMsystemsismuchmoresuitableforproductioninasteadyenvironmentthaninadynamicallychangingenvironmentbecauseitissodiffculttoapplycontrolhierarchychangesimmediatelytotheequipment.Furthermore,itisdiffculttomeetdynamicallychangingcustomerrequirementsbecausethehierarchicalcontrolarchitectureisnotflexibleenoughtohandlethereconfigurationoftheshop.Therefore,themanufacturingsystemoftomorrowshouldbeflexible,highlyreconfigurable,andeasilyadaptabletothedynamicenvironment.Furthermore,itshouldbeanintelligent,autonomous,anddistributedsystemcomposedofindependentfunctionalmodules.Tocopewiththeserequirements,newmanufacturingparadigmssuchasabionic/biologicalmanufacturingsystem(BMS)6,7,aholonicmanufacturingsystem(HMS)8,9,andafractalmanufacturingsystem(FrMS)1013havebeenproposed.Tharumarajahetal.14provideacomprehensivecomparisonamongaBMS,aHMS,andanFrMSintermsofdesignandoperationalfeatures.AnFrMSisanewmanufacturingconceptderivedfromthefractalfactoryintroducedbyWarnecke13.Itisbasedontheconceptofautonomouslycooperatingmulti-agentsreferredtoasfractals.ThebasiccomponentoftheFrMS,referredtoasabasicfractalunit(BFU),consistsoffivefunctionalmodulesincludinganobserver,ananalyzer,aresolver,anorganizer,andareporter10,11.ThefractalarchitecturalmodelrepresentsahierarchicalstructurebuiltfromtheelementsofaBFU,andthedesignofabasicunitincorporatesasetofpertinentattributesthatcanfullyrepresentanylevelinthehierarchy12.Inotherwords,thetermfractalcanrepresentanentiremanufacturingshopatthehighestleveloraphysicalmachineatthebottom-level.EachBFUprovidesservicesaccordingtoanindividual-levelgoalandactsindependentlywhileattemptingtoachievetheshoplevelgoal.AnFrMShasmanyadvantagesforadistributedanddynamicmanufacturingenvironment.Automaticreconfigurationofasystemthroughadynamicrestructuringprocess(DRP)isthemostdistinctivecharacteristicoftheFrMS.Inthispaper,thescopeofthereconfigurationdoesnotincludereconfigurablehardware15andexternallayoutdesign.Rather,itfocusesontheinteriorstructureofsoftwarecomponentsthatcanbereorganizedwithsoftwaremanipulations.Thereconfigurationorrestructuringinthispaperconsidersbothdynamicclusteringoftheagentsandconstruction/destruction/cloningofagents,whichaffectthenumberofagentsinthesystem.ThefunctionofafractalisnotspecificallydesignatedatthetimeofitsfirstinstallationintheFrMS.Thereconfigurationaddressedinthispaperalsoincludessituationswheretheagentsenrollmentsarechanged,meaningthattheagentsareassignedanewgoalandnewjobs,buttheircompositiondoesnotchange.Thispaperfocusesonformalmodelingofagentsandfractal-specificcharacteristicsthatwillprovideafoundationforthedevelopmentoftheFrMS.Becauseassociateddifficultieshave,todate,preventedafractal-basedsystemfrombeingembodied,itisnecessarytofirstexplicitlydefineaconcept,mechanisms,andcharacteristics.3Theobjectiveofthispaper,therefore,istoclearlydefineandmodelfractal-specifccharacteristicsforamanufacturingsystemtohavesuchcharacteristics.Inordertodeveloptheagents,interandintra-fractalactivitiesarefirstclarified.Then,dynamicactivitiesforeachagentandrelationshipsbetweenagentsaremodeled.InordertomorefullydeveloptheFrMS,severalfractal-specificcharacteristicsarealsomodeled.Tosupportembodimentofmodeledcharacteristics,amethodfordealingwithinformationaboutproducts,orders,andresourcesintheFrMSisinvestigated.Throughthisresearch,mechanismsofagentsandcharacteristicsoftheFrMScanbedescribedwithsimplediagramsthatmakethesystemeasiertounderstand.TheworkcontainedinthispaperextendstheFrMSfrompreviouspapersbyemphasizinganddetailingitscharacteristics.Theactivitiesofagentsarespecifiedusingactivitymodelssothattheagentscanusetheactivitymodelstoforecasttheirnextactivitiesatrun-time.Therestofthispaperisorganizedasfollows:Section2describesfunctionsanddynamicactivitiesofagentsusingfunctionalandactivitymodelsofunifiedmodelinglanguage(UML).InSection3,inter-andintra-fractalactivitiesarespecified.Severalfractal-specificcharacteristicsaredescribedusingUMLmodelsinSection4.Section5describesamethodfordealingwithinformationaboutproductsandresourcesintheFrMS.Section6concludesthepaper.2.Agent-basedfractalmanufacturingsystem(FrMS)2.1.BackgroundofanFrMSAnoverviewoftheFrMSisdepictedinFig.1.Everycontrollerateverylevelinthesystemhasaselfsimilarfunctionalstructurecomposedoffunctionalmodules.Inaddition,eachofthesemodules,regardlessofitshierarchicallevel,consistsofasetofagents.Aftertheinitialsetupofasystem,theconfigurationofthesystemmayneedtobereorganizedinresponsetounexpectedeventssuchasmachinebreakdown.Thesystemwillalsoneedtobereconfiguredwhenthesetofpartstobeproducedinthesystemchangesduetoachangeincustomerneeds.Inthesecases,fractalsintheFrMSautonomouslyanddynamicallychangetheirstructure,viatheactionsofagentsfortheappropriateworkingmechanismsofthefractals.Fig.1showstwofacilitylayoutsandthecorrespondingcompositionsoffractalsbeforeandaftertherestructuringprocess.Whenamachine(M)andarobot(R3)areaddedtothesystem,fractalsreorganizetheirinteriorconfigurationswiththemechanismofdynamicrestructuringprocessinawaythatthesystemcontinuestoworkwithgreatestefficiency.AfractalconsistsoffivefunctionalmodulesillustratedwiththeirrelationshipsinFig.2.Thefunctionsofeachmodulecanbedefineddependingupontheapplicationdomain.Fig.1.ReorganizationofthesystemusingadynamicrestructuringprocessintheFrMS.However,whenthetargetdomainisdetermined,themainfunctionsofeachmodulewillbe4consistentthroughoutthesystem.Forexample,thefunctionofaresolvermaybedifferentdependinguponwhetheritisdefinedforcontrollingamanufacturingsystemorformanagingsupplychains.However,themainfunctionofaresolverinamanufacturingsystemissimilartootherresolversinthatsystemregardlessoftheirlevelinthehierarchy.Abottom-levelfractalhassimilarfunctionstothoseofaconventionalequipmentcontrollerinaSFCS.Afractal,whichisdirectlyconnectedtoequipment(e.g.machine,robot,etc.),receivessensorysignalsofequipmentandreturnsmessagesorcommands.Thefunctionofanobserveristomonitorthestateoftheunit,toreceivemessagesandinformationfromouterfractals,andtoFig.2.FunctionalmodulesandrelationshipsofafractalinanFrMS.transmitcompositeinformationtocorrespondentfractals.Thefunctionofananalyzeristoanalyzealternativejobprofileswithstatusinformation,toratedispatchingrules,andtosimulateanalyzedjobprofilesinreal-time.Theanalyzerfinallyreportsresultstotheresolversothattheresolvercanusethemtomakedecisions.Aresolverplaysthemostimportantroleinafractal,generatingjobprofiles,goal-formationprocesses,anddecision-makingprocesses.Duringgoal-formationprocesses,theresolvermayemployavarietyofnumericaloptimizationorheuristictechniquestooptimizethefractalsgoal.Ifnecessary,theresolverexecutesnegotiations,cooperation,andcoordinationamongfractals.Thefunctionofanorganizeristomanagethefractalstatusandfractaladdresses,particularlyfordynamicrestructuringprocesses.Theorganizermayusenumericaloptimizationtechniquestofindanoptimalconfigurationwhilereconfiguringfractals.Thefractalstatusisusedtoselectthebestjobprofileamongseveralalternatives,andthefractaladdressisusedtofindthephysicaladdressofthefractal(e.g.machine_name,port_number,etc.)onthenetwork.Thefunctionofareporteristoreportresultsfromallprocessesinafractaltoothers.Inthecaseofabottom-levelcontroller,thefractalissimilartoatraditionalequipmentcontroller.Therefore,mostofitsmessagesarecommandsforcontrollingthehardware.2.2.AgentsinanFrMSAgenttechnologyhasbeenwidelyusedforvariousapplicationsincludinginformationfilteringandgathering16,knowledgemanagement17,supplychainmanagement18,