简介:Inthenormaloperationcondition,aconventionalsquare-rootcubatureKalmanfilter(SRCKF)givessufficientlygoodestimationresults.However,ifthemeasurementsarenotreliable,theSRCKFmaygiveinaccurateresultsanddivergesbytime.ThisstudyintroducesanadaptiveSRCKFalgorithmwiththefiltergaincorrectionforthecaseofmeasurementmalfunctions.Byproposingaswitchingcriterion,anoptimalfilterisselectedfromtheadaptiveandconventionalSRCKFaccordingtothemeasurementquality.Asubsystemsoftfaultdetectionalgorithmisbuiltwiththefilterresidual.Utilizingaclearsubsystemfaultcoefficient,thefaultysubsystemisisolatedasaresultofthesystemreconstruction.Inordertoimprovetheperformanceofthemulti-sensorsystem,ahybridfusionalgorithmispresentedbasedontheadaptiveSRCKF.Thestateanderrorcovariancematrixarealsopredictedbythepriorifusionestimates,andareupdatedbythepredictedandestimatedinformationofsubsystems.Theproposedalgorithmswereappliedtothevesseldynamicpositioningsystemsimulation.TheywerecomparedwithnormalSRCKFandlocalestimationweightedfusionalgorithm.ThesimulationresultsshowthatthepresentedadaptiveSRCKFimprovestherobustnessofsubsystemfiltering,andthehybridfusionalgorithmhasthebetterperformance.Thesimulationverifiestheeffectivenessoftheproposedalgorithms.
简介:Theobjectiveofthisworkistoanalysefatiguereliabilityofdeckstructuressubjectedtocorrelatedcrackgrowth.Thestressintensityfactorsofthecorrelatedcracksareobtainedbyfiniteelementanalysisandbasedonwhichthegeometrycorrectionfunctionsarederived.TheMonteCarlosimulationsareappliedtopredictthestatisticaldescriptorsofcorrelatedcracksbasedontheParis-Erdoganequation.Aprobabilisticmodelofcrackgrowthasafunctionoftimeisusedtoanalysethefatiguereliabilityofdeckstructuresaccountingforthecrackpropagationcorrelation.Adeckstructureismodelledasaseriessystemofstiffenedpanels,whereastiffenedpanelisregardedasaparallelsystemcomposedofplatesandarelongitudinal.Ithasbeenproventhatthemethoddevelopedherecanbeconvenientlyappliedtoperformthefatiguereliabilityassessmentofstructuressubjectedtocorrelatedcrackgrowth.
简介:<正>Glasgow,UK18th-20thAugust2014AbouttheconferenceTheconferencewillbringtogetherresearchers,practitionerstoaddressthesafetyandreliabilityissuesasapplicabletodifferentstagesintheanalysis,designconstructionandin-servicelifeofmarinestructuressuchasship,offshore,submergedstructuresandtherenewableenergystructures.Thiswillinvolveadvancedanalysisbothforstrengthandloadmodelinordertoestablishsafetylevelbothfordeterministicmodel(WSDmethod)andforreliabilitybaseddesign(LRFDmethod).Oneoftheaimsofthedesignshouldbetoachieveadequatebutnotexcessivelevelofsafetywhichcanbesatisfiedthroughreliabilitybasedmethodandthistakesintoaccountuncertaintiesofdesignvariables.CurrentmoderncodesaretryingtoprovidedesignproceduresonLRFDformatalthoughnoexplicitreliabilityanalysisisdonetoarrivethesepartialsafetyfactors.Thisconferencewilldealwithalltheseissuesandseehowthesetechniquesareappliedtovarioustypesofmarinestructures.Glasgow,thevenueforthisconferenceisacitywhichhaslotofattractions.TheworldfamousLoch-LomondisonlyfewmilesawayandEdinburghis50minutesjourneybytrain.Thecitywillalsohostthe2014CommonwealthGames.