简介:考虑动态输出反馈控制下Euler-Bernoulli梁的振动抑制问题,证明了系统算子生成的C0-半群,不指数稳定但渐近稳定.且当初值充分光滑时,利用Riesz基方法估计出系统能量多项式衰减.
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简介:利用Bernoulli多项式和Bernoulli函数,给出了连续可微函数的Bernoulli表示,并用这种表示来解决一类差分方程的通解问题。
简介:Basedonthetheoryofcalculusofvariation,somesuffcientconditionsaregivenforsomeEuler-LagrangcequationstobeequivalentlyrepresentedbyfiniteoreveninfinitemanyHamiltoniancanonicalequations.Meanwhile,somefurtherapplicationsforequationssuchastheKdVequation,MKdVequation,thegenerallinearEulerLagrangeequationandthecylindricshellequationsaregiven.
简介:TheregularsolutionsoftheisentropicEulerequationswithdegeneratelineardampingforaperfectgasarestudiedinthispaper.Andacriticaldegeneratelineardampingcoefficientisfound,suchthatifthedegeneratelineardampingcoefficientislargerthanitandthegasliesinacompactdomaininitially,thentheregularsolutionwillblowupinfinitetime;ifthedegeneratelineardampingcoefficientislessthanit,thenundersomehypothesesontheinitialdata,theregularsolutionexistsglobally.
简介:Inthispaper,theuniquenessofstationarysolutionswithvacuumofEulerPoissonequationsisconsidered.Throughanonlineartransformationwhichisafunctionofdensityandentropy,thecorrespondingproblemcanbereducedtoasemilinearellipticequationwithanonlinearsourcetermconsistingofapowerfunction,forwhichtheclassicaltheory[4]'[9]oftheellipticequationsleadstheauthorstotheuniquenessresultundersomeassumptionsontheentropyfunctionS(x).Asanexample,theauthorsgettheuniquenessofstationarysolutionswithvacuumofEuler-PoissonequationsforS(x)=|x|θandθ∈{0}∪[2(N-2),+∞).
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简介:TheauthorsconsidertheEulerequationsforacompressiblefluidinonespacedimensionwhentheequationofstateofthefluiddoesnotfulfillstandardconvexityassumptionsandviscosityandcapillarityeffectsaretakenintoaccount.Atypicalexampleofnonconvexcon-stitutiveequationforfluidsisVanderWaals'equation.Thefirstordertermsofthesepartialdifferentialequationsformanonlinearsystemofmixed(hyperbolic-elliptic)type.Foraclassofnonconvexequationsofstate,anexistencetheoremoftravelingwavessolutionswitharbitrarylargeamplitudeisestablishedhere.Theauthorsdistinguishbetweenclassical(compressive)andnonclassical(undercompressive)travelingwaves.ThelatterdonotfulfillLaxshockinequali-ties,andarecharacterizedbytheso-calledkineticrelation,whosepropertiesareinvestigatedinthispaper.
简介:Thewell-posednessoftheinitialvalueproblemoftheEulerequationswasmainlydiscussedbasedonthestratificationtheory,andthenecessaryandsufficientconditionsofwell-posednessarepresentedforsomerepresentativeinitialorboundaryvalueproblem,thusthestructureofsolutionspaceforlocal(exact)solutionoftheEulerequationsisdetermined.Moreoverthecomputationformulasoftheanalyticalsolutionofthewell-posedproblemarealsogiven.