简介:Thenaturalmeasureofacertainareainphasespaceisdefinedfirstly.Onthebasisofnaturalmeasure,theexpressionofLyapunovexponentbasedonunstableperiodicorbits(UPOs)ofchaoticsystemsisdeducedfromtheoreticalaspect.Then,bymeansoftheinherentrelationbetweenUPOsandsystematicLyapunovexponent,thetransitionalmechanismandrouteofchaoticsystemsfromlow-dimensionalchaostohigh-dimensionalchaosareexplained.Intheend,anovelmethodforcomputingsystematicLyapunovexponentsbasedonUPOsisproposed.Itscomputingprocedureisalsosummarized.ThechaoticsystemdescribedbyHenonmapistakenasexample.ThroughcalculatingtheLypunovexponentsofthissystem,validityofthesuggestedmethodisverified.