简介:
简介:Thispaperaddressesanonlinearfeedbackcontrolproblemforthechaoticarchmicro-electro-mechanicalsystemwithunknownparameters,immeasurablestatesandpartialstate-constraintsubjectedtothedistributedelectrostaticactuation.Toreflectinherentpropertiesanddesigncontroller,thephasediagrams,bifurcationdiagramandPoincaresectionarepresentedtoinvestigatethenonlineardynamics.TheauthorsemployasymmetricbarrierLyapunovfunctiontopreventviolationofconstraintwhenthearchmicro-electro-mechanicalsystemfacessomelimits.AnRBFneuralnetworksystemintegratingwithanupdatelawisadoptedtoestimateunknownfunctionwitharbitrarilysmallerror.Toeliminatechaoticoscillation,aneuro-adaptivebacksteppingcontrolschemefusedwithanextendedstatetrackingdifferentiatorandanobserverisconstructedtolowerrequirementsonmeasuredstatesandprecisesystemmodel.Besides,introducinganextendedstatetrackingdifferentiatoravoidsrepeatedderivativeforthevirtualcontrolsignalassociatedwithconventionalbackstepping.Finally,simulationresultsarepresentedtoillustratefeasibilityoftheproposedscheme.
简介:Fromamathematicalmodelofonekindcomplicatedfinancialsystem,correspondinglocaltopologicalstructuresofsuchkindsystemonconditionofcertainparametercombination,unstableequilibriumpointofthesystem,conditionsonwhichHopfbifurcationiscreatedandstabilityofthelimitcirclecorrespondingtotheHopfbifurcationaswellasconditiononwhichthelimitcircleisstablehavebeenstudied.FromrelationshipbetweeneachparameterandtheHopfbifurcationallthewaytoroutewhichleadstochaosetchavebeenstudied.Followingtheabove,conditionsonwhichcomplicatedbehaviorscreatedlocallyinsuchkindsystemhasbeenanalyzed.Byapplyingfractaldimension,Lyapunovindex,theintrinsiccomplexityofthesystemonsuchconditionhasbeenstudied,andresultofthenumericalsimulationprovesthetheoryofthispapercorrect.