简介:TheproblemofpicksequencingintherotaryrackS/Rsystem(PPS-RRS)isinvestigatedwiththeobjectiveofminimizingtheexecutiontime.TherotaryrackS/RsystemconsistsofoneS/Rmachineandmultiplelevelsofcarouselsthatcanrotateindependentlyinbi-directions.Theroutingpolicy,namelythedecisiononthestorageorretrievalsequence,dominatestheefficiencyandthethroughputforsuchS/Rsystems,duetothecomplicatedrelationshipbetweenalllevelsofcarouselsandtheS/Rmachine.ForthepurposeofoptimizingthePPS-RRS,acomputationalmodelisdevelopedintermsofexecutiontimeforpickingmultipleitemsinonetrip.CharacteristicsofthePPS-RRSareanalyzedandalocalsearchheuristicbasedonanewlyproposedneighborhoodispresented.Integratedwiththeproposedlocalsearchprocedureanewhybridgeneticalgorithmisdeveloped.Experimentalresultsdemonstratethestructurecharacteristicsofgoodsequenceandtheefficiencyandeffectivenessoftheproposedsequencingalgorithms.
简介:Adiscretegain-varyingunknowninputobserver(UIO)methodispresentedforactuatorfaultdetectionandisolation(FDI)problemsinthispaper.Anovelresidualschemetogetherwithamovinghorizonthresholdisproposed.ThisdesignmethodologyisappliedtoanonlinearF16systemwithpolynomialaerodynamicscoefficientexpressions,wherethecoefficientexpressionsfortheF16systemandUIOsmaybeslightlydifferent.ThesimulationresultsillustratethatasatisfactoryFDIperformancecanbeachievedevenwhentheF16systemisundertheenvironmentofmodeluncertainties,exogenousnoiseandmeasurementerrors.