简介:针对STCW公约马尼拉修正案履约过渡期船员教育和培训工作,从中国海事局下发的"关于印发《STCW公约马尼拉修正案过渡规定实施办法》的通知"等对航海培训机构的要求和影响进行分析,提出履约过渡期的应对策略。
简介:Theaddedmasscoefficientandthewaterlevelindexformulasforthesame-phaseandanti-phasevibrationofrectangularliquidtanks'bulkheadswerederivedbasedondrymodetheory.Threefluid-structureinteractionnumericalmethodsincludingFluidFEMandFluidBEMwereusedinthiscase.ThecomparisonofnumericalandtheoreticalresultsbythepresentmethodshowsthatANSYS/FluidS0ismorecredible,theNASTRAN/VirtualMassMethodismoresuitableforengineeringcalculationsandresultsofthesame-phasevibrationbythepresentmethodismoreaccurate.
简介:S-surfacecontrolhasproventobeaneffectivemeansformotioncontrolofunderwaterautonomousvehicles(AUV).Howevertherearestillproblemsmaintainingsteadyprecisionofcourseduetotheconstantneedtoadjustparameters,especiallywheretherearedisturbingcurrents.Thusanintelligentintegralwasintroducedtoimproveprecision.AnexpertS-surfacecontrolwasdevelopedtotunetheparameterson-line,basedontheexpertsystem,itprovidesS-surfacecontrolaccordingtopracticalexperienceandcontrolknowledge.Topreventcontroloutputover-compensation,afuzzyneuralnetworkwasincludedtoadjusttheproductionrulestotheknowledgebase.ExperimentswereconductedonanAUVsimulationplatform,andtheresultsshowthattheexpertS-surfacecontrollerperformsbetterthananS-surfacecontrollerinenvironmentswithcurrents,producinggoodsteadyprecisionofcourseinarobustway.
简介:Arraycalibrationisimportantinengineeringpractice.Inthispaper,fastcalibrationmethodsforaULA'sgainandphaseerrorsbothinfarandnearfieldsareproposed.Inthefarfield,usingasinglesoundsourcewithoutexactorientation,thismethodhorizontallyrotatesthearrayexactlyonce,performseigenvaluedecompositionforthecovariancematrixofreceiveddata,thencomputesthegainandphaseerroraccordingtotheformulas.Inthenearfield,usingthesamesinglesoundsource,itisnecessarytorotatethearrayhorizontallyatmostthreetimes,buildequationsaccordingtogeometricrelations,thensolvethem.Usingtheformulaproposedinthispaper,sphericalwavesaremodifiedintoplanewaves.Theneigenvaluesdecompositionisperformed.Thesetwocalibrationmethodswereshowntobevalidbysimulationandarefast,accurateandeasytouse.Finally,ananalysisoffactorsinfluencingestimationprecisionisgiven.
简介:Oceanographicsurvey,orothersimilarapplicationsshouldbetheapplicationsofmultipleAUVs.Inthispaper,theskill&simulationbasedhybridcontrolarchitecture(S2BHCA)asthecontroller'sdesignreferencewasproposed.Itisamulti-robotcooperationorientedintelligentcontrolarchitecturebasedonhybridideas.TheS2BHCAattemptstoincorporatethevirtuesofthereactivecontrollerandofthedeliberativecontrollerbyintroducingtheconceptofthe"skill".Theadditionalonlinetasksimulationabilityforcooperationissupported,too.Asanapplication,amultipleAUVcontrolsystemwasdevelopedwiththree"skills"fortheMCMmissionincludingtwodifferentcooperativetasks.Thesimulationandtheseatrialsshowthatsimpletaskexpression,fastreactionandbettercooperationsupportcanbeachievedbyrealizingtheAUVcontrollerbasedontheS2BHCA.