简介：Thesonarsystemswhichworkinshallowwaterenvironmentsuffergreatlyfrominfluencesofoceanicnoises,acousticpropagationseesawandmultipath.Withshallowwaterenvironmentandhigherrange-bearingresolutionofsonarsystems,therearenotenoughindependentscattererswithinaresolutioncellforthecentrallimittheoremtohold.Thereverberationenvelopeprobabilitydensityfunction(pdf)divergesfromRayleighpdf.Thenon-Rayleighpdfwithheaviertailsiscomplicated,anditisdifficulttoestimatethefunctionparametersaccuratelyinrealtime.WithCFAR(ConstantFalseAlarmRate)processingofthereverberationenvelopedata,whichattenuatestheheaviertailsdatavaluestotheestimatedbackgroundpowervalues,thedatareverberationistransformedfromnon-RayleighdistributiontoapproximatelyRayleighdistribution.Sinceitgetsridoftheinterferenceswhichaffecttheestimationofbackgroundpower,thedetectorcanestimatetheoceanicbackgroundpowerlevelmoreaccurately.Withtherationalestimationofbackgroundpowerlevel,theCFARdetectioncapabilityisbetterandrobust.Withprocessingofhighresolutionsonardata,itisshownthattheproposedalgorithmisefficient.

简介：Inthisstudy,aporousinsertedregenerativethermaloxidizer(PRTO)systemwasdevelopedfora125kWindustrialcopper-meltingfurnace,duetoitsadvantagesoflowNOxemissionsandhighradiantefficiency.Zirconiumdioxide(ZrO2)ceramicfoamswereplacedintothecombustionzoneofaregenerativethermaloxidizer(RTO).DifferentperformancecharacteristicsoftheRTOandPRTOsystems,includingpressuredrop,temperaturedistribution,emissions,andenergyefficiency,wereevaluatedtostudytheeffectsoftheporousinsertsonnon-premixedCH4combustion.ItwasfoundthatthePRTOsystemachievedasignificantreductionintheNOxemissionlevelandafuelsavingofapproximately30%comparedtotheRTOsystem.Itismostsuitableforaleancombustionprocessatanequivalenceratio<0.4withNOxandCOemissionlevelswithin0.002%-0.003%and0.001%-0.002%,respectively.

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简介：Asimulationforpistoneffectinsupercriticalcarbondioxidebyemployingasimplemodelisconducted.Inthefirstplace,thethermalpropertiesofcarbondioxidenearitsliquid-vaporcriticalpointarediscussed.Itiscalculatedthattheheatcapacityratioandisobaricexpansioncoefficientofsupercriticalfluidsareextremelyhigh.Furthermore,thesimulationforpistoneffectinsupercriticalcarbondioxidebetweentwoinfiniteverticalwallsispresented.Thenumericalresultsprovethatpistoneffecthasamuchfasterspeedofheattransferthanthermalconductionundermicrogravityconditions.Moreover,thepistoneffectturnsouttobestrongerwhenclosertothecriticalpoint.

简介：Thispaperdescribestheeffectsofnon-equilibriumairplasmageneratedbyadielectricbarrierdischarge（DBD）onthecombustionoflowheatingvaluefuels.TheexperimentalresultsindicatethatadditionofaverysmallamountofenergytotheairflowintheformofDBDsignificantlyimprovestheflamestability.Moreover,maincombustioncharacteristicssuchasflamepropagationspeed,combustionintensityandleanblow-offlimitsarealsoenhancedbytheeffectofplasma.SomeactiveradicalssuchasexcitedOatomandexcitedN2moleculeareobservedbyspectrographinthedischargearea.BasedontheresultsofnumericalinvestigationwecanconcludethattheseactiveradicalsgeneratedindischargeareacanacceleratetheproductionrateofactiveOHradicalwhichplaysakeyroleintheoxidationprocessoflowheatingvaluefuel,andthusthewholecombustionprocessisaccelerated.

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简介：Inthisarticle,byusingtheoryoflinearevolutionsystemandSchauderfixedpointtheorem,weestablishasufficientresultofexactnullcontrollabilityforanonautonomousfunctionalevolutionsystemwithnonlocalconditions.Inparticular,thecompactnesscondi-tionorLipschitzconditionforthefunctionginthenonlocalconditionsappearinginvariousliteraturesisnotrequiredhere.Anexampleisalsoprovidedtoshowanapplicationoftheobtainedresult.

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简介：Controlofsupersonicflowfieldswithshockwaveisimportantforsomeindustrialfields.Therearemanystudiesforcontrolofthesupersonicflowfieldsusingactiveorpassivecontrol.Whennon-equilibriumcondensationoccursinasupersonicflowfield,theflowisaffectedbylatentheatreleased.Manystudiesforthecondensationhavebeenconductedandthecharacteristicshavebeenalmostclarified.Further,itwasfoundthatnon-equilibriumcondensationcancontroltheflowfield.Inthesestudies,thecondensationoccursacrossthepassageoftheflowfieldanditcausesthetotalpressurelossintheflowfield.However,localoccurrenceofnon-equilibriumcondensationintheflowfieldmaychangethecharacteristicsoftotalpressurelosscomparedwiththatbythecondensationacrossthepassageofthenozzleandtherearefewforresearchesoflocallyoccurrednon-equilibriumcondensationinsupersonicflowfield.Thepurposeinthepresentstudyistoclarifytheeffectoflocaloccurrenceofnon-equilibriumcondensationonthetransonicflowfieldinanozzlewithacircularbump.Asaresult,localoccurrenceofnon-equilibriumcondensationreducedtheshockstrengthandtotalpressurelossinthetransonicflowfieldbyflowingthemoistairfromtrailingedgeofthecircularbumptothemainstream.

简介：Westudytheexistenceoftravelingwavesolutionsforanonlocalandnon-monotonedelayedreaction-difusionequation.Basedontheconstructionoftwoassociatedauxiliaryreactiondifusionequationswithmonotonicityandbyusingthetravelingwavefrontsoftheauxiliaryequations,theexistenceofthepositivetravelingwavesolutionsforc≥cisobtained.Also,theexponentialasymptoticbehaviorinthenegativeinfnitywasestablished.Moreover,weapplyourresultstosomereactiondifusionequationswithspatio-temporaldelaytoobtaintheexistenceoftravelingwaves.Theseresultscover,complementand/orimprovesomeexistingonesintheliterature.

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简介：Astudyispresentedformagnetohydrodynamics(MHD)flowandheattransfercharacteristicsofaviscousincompressibleelectricallyconductingmicropolarfluidinachannelwithstretchingwalls.ThemicropolarmodelintroducedbyEringenisusedtodescribetheworkingfluid.Thetransformedselfsimilarordinarydiferentialequationstogetherwiththeassociatedboundaryconditionsaresolvednumericallybyanalgorithmbasedonquasi-linearizationandmultileveldiscretization.Theefectsofsomephysicalparametersontheflowandheattransferarediscussedandpresentedthroughtablesandgraphs.Thepresentinvestigationsmaybebeneficialintheflowandthermalcontrolofpolymericprocessing.

简介：Non-commutativePoissonalgebrasarethealgebrashavingbothanassociativealgebrastructureandaLiealgebrastructuretogetherwiththeLeibnizlaw.Inthispaper,thenon-commutativepoissonalgebrastructuresontheLiealgebrassln(Cq)aredetermined.

简介：Inthispaper,theauthorsestablishtheboundednessofmultilinearcommutatorsgeneratedbyaMarcinkiewiczintegraloperatorandaRBMO(μ)functiononhomogeneousMorrey-Herzspaceswithnondoublingmeasures.

简介：Thispaperpresentsanewstrategyofusingtheradialintegrationboundaryelementmethod(RIBEM)tosolvenon-homogeneousheatconductionandthermoelasticityproblems.Inthemethod,theevaluationoftheradialin-tegralwhichisusedtotransformdomainintegralstoequivalentboundaryintegralsiscarriedoutonthebasisofelementalnodes.Asaresult,thecomputationaltimespentinevaluatingdomainintegralscanbesavedconsiderablyincomparisonwiththeconventionalRIBEM.Threenumericalexamplesaregiventodemonstratethecorrectnessandcomputationalefficiencyoftheproposedapproach.

简介：Thisarticleprovestheexistenceanduniquenessofsolutiontotwo-parameterstochasticVolterraequationwithnon-LipschitzcoefficientsanddrivenbyBrowniansheet,wherethemaintoolisBihari'sinequalityintheplane.Moreover,wealsodiscussthetimeregularitypropertyofthesolutionbyKolmogorov'scontinuitycriterion.

简介：Anumericalstudyofanon-Darcymixedconvectiveheatandmasstransferflowoveraverticalsurfaceembeddedinaporousmediumundertheefectsofdoubledispersion,melting,andthermalradiationisinvestigated.Thesetofgoverningboundarylayerequationsandtheboundaryconditionsistransformedintoasetofcouplednonlinearordinarydiferentialequationswiththerelevantboundaryconditions.ThetransformedequationsaresolvednumericallybyusingtheChebyshevpseudospectralmethod.Comparisonsofthepresentresultswiththeexistingresultsintheliteraturearemade,andgoodagreementisfound.Numericalresultsforthevelocity,temperature,concentrationprofiles,andlocalNusseltandSherwoodnumbersarediscussedforvariousvaluesofphysicalparameters.

简介：Theproblemsonthenon-uniquenessandstabilityofatwo-familyfiberreinforcedanisotropicincompressiblehyper-elasticsquaresheetunderequibiaxialtensiledeadloadingareexaminedwithintheframeworkoffiniteelasticity.Foratwo-familyfiber-reinforcedsquaresheet,whichisin-planesymmetricandsubjectedtothein-planesymmetrictensionindeadloadingontheedges,threesymmetricallydeformedconfigurationsandsixasymmetricallydeformedconfigurationsarepossibleforanyvaluesoftheloading.Moreover,anotherfourbifurcatedasymmetricallydeformedconfigurationsarepossiblefortheloadingbeyondacertaincriticalvalue.Thestabilityofallthesolutionsisdiscussedincomparisonwiththeenergyofthesheet.Itisshownthatonlyoneofthesymmetricsolutionsisstablewhentheloadingislessthanthecriticalvalue.However,thissymmetricsolutionwillbecomeunstablewhentheloadingislargerthanthecriticalvalue,whileoneofthefourbifurcatedasymmetricsolutionswillbestable.

简介：Uncertaintyisinherentandunavoidableinalmostallengineeringsystems.Itisofessentialsignificancetodealwithuncertaintiesbymeansofreliabilityapproachandtoachieveareasonablebalancebetweenreliabilityagainstuncertaintiesandsystemperformanceinthecontroldesignofuncertainsystems.Nevertheless,reliabilitymethodswhichcanbeuseddirectlyforanalysisandsynthesisofactivecontrolofstructuresinthepresenceofuncertaintiesremaintobedeveloped,especiallyinnon-probabilisticuncertaintysituations.Inthepresentpaper,theissueofvibrationcontrolofuncertainstructuresusinglinearquadraticregulator(LQR)approachisstudiedfromtheviewpointofreliability.Ane?cientnon-probabilisticrobustreliabilitymethodforLQR-basedstaticoutputfeedbackrobustcontrolofuncertainstructuresispresentedbytreatingboundeduncertainparametersasintervalvariables.Theoptimalvibrationcontrollerdesignforuncertainstructuresiscarriedoutbysolvingarobustreliability-basedoptimizationproblemwiththeobjectivetominimizethequadraticperformanceindex.Thecontrollerobtainedmaypossessoptimumperformanceundertheconditionthatthecontrolledstructureisrobustlyreliablewithrespecttoadmissibleuncertainties.Theproposedmethodprovidesanessentialbasisforachievingabalancebetweenrobustnessandperformanceincontrollerdesignofuncertainstructures.Thepresentedformulationsareintheframeworkoflinearmatrixinequalityandcanbecarriedoutconveniently.Twonumericalexamplesareprovidedtoillustratethee?ectivenessandfeasibilityofthepresentmethod.