简介:Thispaperdescribessomeinertialalgorithmsfortheapproximationofnonlincarevolutionequationsandstudiesaprioriestimatesoftheapproximatesolutiomandthestabilityoftheinertialalgorithms.
简介:PotentialenergysurfaceofHNOSsystemisinvestigatedbymeansofMP2methodwith6-311++G(d,p)basisset.TheenergyforeachminimumandsaddlepointonthepotentialenergysurfaceiscorrectedattheQCISD(T)/6-311++G(3df,2p)leveloftheorywithzero-pointvibrationalenergyincluded.Asaresult,eighteenisomersaretheoreticallypredictedandcis-HNSOisfoundtobeglobalminimumonthepotentialenergysurface,Wherein,fourteenisomersareconsideredaskineticallystablespecies,andshouldbeexperimentallyobserved.ComparisonsaremadeforHNOSsystemwithitsanalogues,HNO2andNHS2.Thenatureofbondingandisomers'stabilityofHNOSsystemaresimilartoHNS2.TheobvioussimilaritiesanddiscrepanciesamongHNOS,HNO2andHNS2areattributedtothehypervalentcapacityofsulfur,oxygenandnitrogenatoms.
简介:Thealmostsurestabilityofhomogeneousviscoelasticplatessubjectedtoarandomwide-bandstationaryin-planeloadisinvestigated.TheviscoelasticbehavioroftheplateisdescribedintermsoftheBo-ltzmannsuperpositionprinciple,therelaxationkernelsofwhicharerepresentedbythesumsofexponents.Ontheassumptionthatthein-planeloadisrandomwide-bandstationaryprocess,sufficientconditionsforal-mostsurestabilityofviscoelasticplatesareobtainedbytheapplicationsofLyapunov’sdirectmethod.
简介:Asingle-axisfluxdecaymodelincludinganexcitationcontrolmodelproposedin[12,14,16]isstudied.AsthebifurcationparameterPm(inputpowertothegenerator)varies,thesystemexhibitsdynamicsemergingfromstaticanddynamicbifurcationswhichlinkwithsystemcollapse.Weshowthattheequilibriumpointofthesystemundergoesthreebifurcations:onesaddle-nodebifurcationandtwoHopfbifurcations.Thestatevariablesdominatingsystemcollapsearedifferentfordifferentcriticalpoints,andtheexcitativecontrolmayplayanimportantroleindelayingsystemfromcollapsing.Simulationsarepresentedtoillustratethedynamicalbehaviorassociatedwiththepowersystemstabilityandcollapse.Moreover,bycomputingthelocalquadraticapproximationofthe5-dimensionalstablemanifoldatanorder5saddlepoint,ananalyticalexpressionfortheapproximatestabilityboundaryisworkedout.
简介:Thestabilityofthethinliquidfilminacapillaryisimportanttothephase-changeheattransferprocessinminiatureofmicrostructures.Fromthebasicequationsformotionandheattransferattheinterfaceofthefilm,itsstabilityistheoreticallystudied.Withevaluationoftheeffectsandrelativemagnitudesofvariousdrivingforcesandwiththeuseoflong-wavetheoryinadditiontolinearstabilityanalysis,thecontrollingequationsaresimplifiedandanevolutionequationforthefilm'sthicknessisobtained.Detailedanalysisontheevolutionequationshowsthatinstabilityoccursfirstinthemeniscusregionandtheinstabilityconditionvarieswithboundaryconditions,geometricalscalesandthermalproperties.Thenumericalresultsagreewellwithearlieroneswithsomefavorableextensionsandimprovements.
简介:Theimportanceofcosmologicalconstantforthecosmologicalmodelsisgiven.Thevariationsofthecosmologicalmodelforparametersλandkwerediscussedrespectively.Nearλ=0,thecosmologicalmodelisunstablewiththechangeofλ,andnearλ=β=0,thecosmologicalmodelisunstablewiththechangeofk.Sowhenweconsiderthestablecosmologicalmodel,wemustconsiderthenonzerocosmologicalconstant.
简介:LetT=(T(t))t≥0beaboundedC-regularizedsemigroupgeneratedbyAonaBanachspaceXandR(C)bedenseinX.WeshowthatifthereisadensesubspaceYofXsuchthatforeveryx∈Y,σu(A,Cx),thesetofallpointsλ∈iRtowhich(λ-A)^-1Cxcannotbeextendedholomorphically,isatmostcountableandσr(A)NiR=Ф,thenTisstable.AstabilityresultforthecaseofR(C)beingnon-denseisalsogiven.Ourresultsgeneralizetheworkonthestabilityofstronglycontinuoussenfigroups.
简介:ThethermalstabilityofNewZealandculturerabbitmusclealdolasewasinvestigatedbydifferentialscanningcalorimetryinthewatercontentrange0.23-3.70gwaterpergprotein.Theexperimentalresultsshowedthatatwatercontentsbelow0.47g/g,anendothermicpeakwasobservedandatwatercontentsabove0.57g/g,anendothermicandanexothermicpeakwerebothobservedonDSCthermogram.Thermaldenaturationresultoftheenzymeandtherelationshipbetweentwotransitiontemperaturesandwatercontentswerefirstreportedinthispaper.Uptonowwehavenotseenanysimilarreportsconcerningtheexothermictransition.
简介:InthispaertheinequalityofLemma1of[1]isextended.BymeansofourinequalityandthemethodofLyapunovfunctionwestudythestabilityoftwokindsoflargeseatedifferentialsystemswithtimelagandthestabilityofahigher-orderdifferentialequationwithtimelag.Thesufficientconditionsforthestability(S.),theasymptoticstability(A.S.),theuniformlyasymptoticstability(U.A.S)andtheexponentialasymptoticstability(E.A.S.)ofthezerosolutionsofthesystermsareobtainedrespectively.
简介:在这篇论文,我们将扩大严格的稳定性到冲动的微分方程。由使用Lyapunov功能,我们将为冲动的微分方程的严格的稳定性得到一些标准,并且我们能看到推动确实贡献系统的严格的稳定性行为。一个例子也在这篇论文被给说明获得的结果的效率。关键词冲动的微分方程-严格的稳定性-Lyapunov功能先生(2000)题目分类34A37-34D99这个工作被中国(60474008)的国家自然科学基础和上海城市(03ZR14095)的自然科学基础支持,中国
简介:ConsiderabackwardheatequationinaboundeddomainΩR2withthenoisydataintheinitialtimegeometry.Theaimistofindthetemperaturefor0<ε<t<T.Forthisill-posedproblem,theauthorsgiveacontinuousdependenceestimateofthesolution.Moreover,theconvergencerateoftheapproximatesolutionisalsogiven.
简介:Inthispaper,weconsidertheboundarystabilizationofthewaveequationwithvariablecoefficientsbyRiemmanniangeometrymethodsubjecttoadifferentgeometricconditionwhichismotivatedbythegeometricmultiplieridentities.Several(multiplier)identities(inequalities)whichhavebeenbuiltforconstantwaveequationbyKormornikandZuazuaaregeneralizedtothevariablecoefficientcasebysomecomputationaltechniquesinRiemmanniangeometry,sothatthepreciseestimatesontheexponentialdecayratearederivedfromthoseinequalitities.Also,theexponentialdecayforthesolutionsofsemilinearwaveequationwithvariablecoefficientsisobtainedundernaturalgrowthandsignassumptionsonthenonlinearity.Ourmethodisrathergeneralandcanbeadaptedtootherevolutionsystemswithvariablecoefficients(e.g.elasticityplates)aswell.
简介:AnSMIBmodelinthepowersystems,especiallythatconceringtheeffectsofhardlimitsonbifurcations,chaosandstabilityisstudied.Parameterconditionsforbifurcationsandchaosintheabsenceofhardlimitsarecomparedwiththoseinthepresenceofhardlimits.Ithasbeenprovedthathardlimitscanaffectsystemstability.Wefindthat(1)hardlimitscanchangeunstableequilibriumintostableone;(2)hardlimitscanchangestabilityoflimitcyclesinducedbyHopfbifurcation;(3)persistenceofhardlimitscanstabilizedivergenttrajectorytoastableequilibriumorlimitcycle;(4)HopfbifurcationoccursbeforeSNbifurcation,sothesystemcollapsecanbecontrolledbeforeHopfbifurcationoccurs.Wealsofindthatsuitablelimitingvaluesofhardlimitscanenlargethefeasibilityregion.Theseresultsarebasedontheoreticalanalysisandnumericalsimulations,suchasconditionforSNBandHopfbifurcation,bifurcationdiagram,trajectories,Lyapunovexponent,Floquetmultipliers,dimensionofattractorandsoon.
简介:ANALYSISOFSTABILITYONELASTICPLATESWITHINITIALIMPERFECTIONSXuKaiyu(徐凯宇)(ReceivedOct.5.1994;CommunicatedPaiLizhou)ANALYSISOFSTA...
简介:Basedonthelinearanalysisofstability,adispersionequationisdeducedwhichdelineatestheevolutionofageneral3-dimensionaldisturbanceonthefreesurfaceofanincompressibleviscousliquidjetinjectedintoagaswithswirl.Here,thedimensionlessparameterJ_eisagainintroduced,inthemeantime,anotherdimensionlessparameterEcalledascirculationisalsointroducedtorepresenttherelativeswirlingintensity.Withrespecttothespatialgrowingdisturbancemode,thenumericalresultsobtainedfromsolvingthedispersionequationrevealthefollowingfacts.First,atthesamevalueofE,inpacewiththechangingofJ_e,thevariationofdisturbanceandthecriticaldisturbancemodestillkeepthesamecharacters.Second,thepresentresultsarethesameasthatofS.P.LinwhenJ_e>1;butintherangeofJ_e<1,it’snomorethecase,theswirldecreasestheaxisymmetricdisturbance,yetincreasestheasymmetricdisturbance,furthermoretheswirlmaymakethecharacterofthemostunstabledisturbancemodechanged(axisymmetricorasymmetric);theaboveactionoftheswirlbecomesmuchstrongerwhenJ_e《1.