学科分类
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377 个结果
  • 简介:Thetightforeignexchangecontrolerahasgonewith,wind,andforeigncurrencyreserveofChinanowisupto300billionUSdollars;once"thecuffofoverseasinvestment",theforeignexchangecontrolsystemwillgowhere?

  • 标签:
  • 简介:SurvivabilityisoneoftheimportantissuesinATM-basednetworkssineevenasinglenetworkelementfailuremaycauseaseriousdataloss.Thispaperintroducesanewrestorationmechanismbasedonmulti-layerATMsurvivablenetworkmanagementarchitecture.ThismechanismintegratesthegeneralcontrolandrestorationcontrolbyestablishingtheWorkingVPslogicalnetwork,BackupVPslogicalnetworkandsparelogicalnetworkinordertooptimallyutilizethenetworkresourceswhilemaintainingtherestorationrequirements.

  • 标签: 异步传输模式 可生存性 恢复 集中控制
  • 简介:Summary1.Thereare12powersystemsincluding5regionalpowersystemswithover1000MWofcapacityeach.In1989CentralandEastChinapowersystemswereinterconnectedbya±500kVHVDCLine.2.Thehierarchicalcontrolorganizationcanbedividedinto5levels,i.e.NCC,6RCCs,25PCCs,250DCCsandmorethan2000CCCs.3.AllcontrolcenterswillbeequippedwithSCADAandEMSinthenearfuture.4.Chinapowersystemhasalarge,dedicatedcommunicationnetworkofitsown.

  • 标签: hierarchical interconnected DEDICATED installed HANDLE Power
  • 简介:Acompoundneuralnetworkisutilizedtoidentifythedynamicnonlinearsystem.Thisnetworkiscomposedoftwoparts:oneisalinearneuralnetwork,andtheotherisarecurrentneuralnetwork.Basedontheinversetheoryacompoundinversecontrolmethodisproposed.Thecontrollerhasalsotwoparts:alinearcontrollerandanonlinearneuralnetworkcontroller.Thestabilityconditionoftheclosed-loopneuralnetwork-basedcompoundinversecontrolsystemisdemonstratedbasedontheLyapunovtheory.Simulationstudieshaveshownthatthisschemeissimpleandhasgoodcontrolaccuracyandrobustness.

  • 标签: 神经系统 智能控制 反向控制 非线性系统
  • 简介:FortheARMAXsystemwithunknowncoefficientstheoptimaladaptivecontrolisdesignedsothatthefollowingrequirementsaremetsimultaneously:1)thetransferfunctionfromareferencesignaltothesystemoutputintheclosedloopequalsaprescribedrationalfunction;2)undertheconstraintmentionedin1)aquadraticlossfunctionisminimized;3)theparameterestimateisstronglyconsistent.

  • 标签: STOCHASTIC system adaptive control with CONSTRAINT
  • 简介:Thecourse-keepingcontrolofunderactuatedhovercraftwithtwoaftpropellerswasconsidered.Thecontroloftheheadingerrorandcross-trackerrorwasaccomplishedbytheyawtorquemerelyinthiscase.Thehovercraftdynamicmodelisnonlinearandunderactuated.AtfirsttheControllabilityofcourse-keepingcontrolforhovercraftwasproved,thenacourse-keepingcontrollawwasderivedthatkeepshovercraftheadingconstantaswellasminimizesthelateralmovementofhovercraft.Theproposedlawguaranteesheadingerrorandswayerrorallconvergetozeroexponentially.Simulationtestswerecarriedouttoillustratetheeffectivenessoftheproposedcontrollaw.Forfurtherresearch,thedisturbanceinfluencewouldbeconsideredinthedynamicequations.

  • 标签: 气垫船 非线性反馈控制 级数收敛 过程控制 数值模拟
  • 简介:Aclassofstationarymodelsofsingularstochasticcontrolhasbeenstudied,inwhichthestateisextendedtosolutionofaclassofS.D.E.fromWienerprocess.Theexistenceofoptimalcontrolhasbeenprovedinallcasesundersomeweakerconditions,andthestructureofoptimalcontrolmaybecharacterized.

  • 标签: 奇异积分控制 WIENER过程 存在性 最优控制
  • 简介:Thispaperpresentsthestabilityofdifferenceapproximationsofanoptimalcontrolproblemforaquasilinearparabolicequationwithcontrolsinthecoefficients,boundaryconditionsandadditionalrestrictions.Theoptimalcontrolproblemhasbeenconveredtooneoftheoptimizationproblemusingapenaltyfunctiontechnique.Thedifferenceapproximationsproblemfortheconsideredproblemisobtained.Theestimationsofstabilityofthesolutionofdifferenceapproximationsproblemareproved.Thestabilityestimationofthesolutionofdifferenceapproximationsproblembythecontrolsisobtained.

  • 标签: 最优控制理论 拟线性抛物方程 补偿函数 稳定性估计
  • 简介:Anewtypecontrolmethodinfrictionweldingissuggestedinthispa-per,thatiscompositivecontrolmethodoffrictiontorqueandfrictiontime,itcalledMtcontrolmethodforshort.TheprincipleofMtcontrolmethodanditsfeatureareconciselyexplained.

  • 标签: CONTROL METHOD FRICTION WELDING FRICTION TORQUE
  • 简介:Aclassoflarge-sealesystems,wheretheoverallobjectivefunctionisanonlinearfunctionofperformanceindexofeachsubsystem,isinvestigatedinthispaper.Thistypeoflarge-scalecontrolproblemisnon-separableinthesenseofconventionalhierarchicalcontrol.Hierarchicalcontrolisextendedinthepapertolarge-scalenon-separablecontrolproblems,wheremultiobjectiveoptimizationisusedasseparationstrategy.Thelarge-scalenon-separablecontrolproblemisembedded,under;ertainconditions,intoafamilyoftheweightedLagrangianformulation.TheweightedLagrangianformulationisseparablewithrespecttosubsystemsandcanbeeffectivelysolvedusingtheinteractionbalanceapproachatthetwolowerlevelsintheproposedthree-levelsolutionstructure.Atthethirdlevel,theweightingvectorfortheweightedLagrangianformulationisadjustediterativelytosearchtheoptimalweightingvectorwithwhichtheoptimaloftheoriginallarge-scalenon-separablecontrolproblemisobtained.Theoreticalbaseofthealgorithmisestablished.Simulationshowsthatthealgorithmiseffective.

  • 标签: LARGE-SCALE system HIERARCHICAL control MULTI-OBJECTIVE optimization.
  • 简介:Basedontheself-excitedvibrationtheoryofice,thevibrationcontroltechnologyofjacketplatformisstudiedinthispaper.Themagnetorheologicalsuspensions(MR)unitischosenasthedamper,thecontrolobjectivefunctionforvibrationexcitedbyiceisdeterminedbyinstantaneousoptimalcontrol(IOC)method,andgeneticalgorithm(GA)isusedtoselecttheoptimalcontrolforce.Forthejacketplatformof40minheightanda3-floordeck,thevibrationresponsesinducedbyicehavebeencalculatedbeforeandaftercontrolconsideringthedifferentthicknessandspeedofice.Itisshownthatthecontrolmethodpresentedinthispapercanreducethevibrationresponseby30%,anditisfeasibletoadoptMRabsorberandGAinthecontrolofvibrationinducedbyice.

  • 标签: 振动控制 导管架平台 遗传算法 瞬间最优控制 IOC GA