简介:Inthispaper,weintroduceaconditionweakerthantheLpdifferentiability,whichwecallCpcondition.Weprovethatifafunctionsatisfiesthisconditionatapoint,thenthereexiststhebestlocalapproximationatthatpoint.WealsogiveanecessaryandsufficientconditionforthatafunctionbeLpdifferentiable.Inaddition,westudytheconvexityofthesetofclusterpointsofthenetofbestappoximationsoff,{Pe(f)}ase→0.
简介:TheHelmholtzequationissometimessupplementedbyconditionsthatincludethespecificationoftheboundaryvalueofthedivergenceoftheunknown.Inthispaper,westudythevectorHelmholtzproblemindomainsofbothC~(1,1)andLipschitz.Wees-tablisharigorousvariationalanalysissuchasequivalence,existenceanduniqueness.Andweproposefiniteelementapproximationsbasedontheuncoupledsolutions.Fi-nallywepresentaconvergenceanalysisanderrorestimates.
简介:1.IntroductionLetRbethecollectionofallrealnumbers,andZthecollectionofallintegers.Iff1(x)andf2(x)aretwofunctionsinL2(R),theinnerproduct
简介:ThispaperproposestheRiceconditionnumbersforinvariantsubspace,singularsubspacesofamatrixanddeflatingsubspacesofaregularmatrixpair.Thefirst-orderperturbationestimationsforthesesubspacesarederivedbyapplyingperturbationexpansionsoforthogonalprojectionoperators.
简介:WeconsiderthenumericalsolutionfortheHelmholtzequationinR~2withmixedboundaryconditions.Thesolvabilityofthismixedboundaryvalueproblemisestab-lishedbytheboundaryintegralequationmethod.BasedontheGreenformula,weexpressthesolutionintermsoftheboundarydata.Thekeytothenumericalreal-izationofthismethodisthecomputationofweaklysingularintegrals.Numericalperformancesshowthevalidityandfeasibilityofourmethod.Thenumericalschemesproposedinthispaperhavebeenappliedintherealizationofprobemethodforinversescatteringproblems.
简介:在这篇论文,包含的微分方程未知函数重申,与一个复杂参数一,在复杂的域ℂ被调查为分析答案的存在。首先,我们在参数上讨论存在和连续依赖一of上述方程的分析答案,由使用,Banach修理了点定理。然后,以及在许多以前的工作,我们与Schröder转变x(z)=y减少方程(αy−1(z))到下列另外一个没有被调用一个辅助方程的未知函数的重复的功能的微分方程。由构造辅助方程的本地可颠倒的分析答案,表格y的分析答案(为原来的反复的微分方程的αy−1(z))被获得。我们讨论在夸张案例中在Schröder转变给的这些α不仅0<|α|<1并且回声,即,在回声附近的统一,而且那些α的一条根(即,接近统一的一条根)在Brjuno状况下面。最后,我们借助于一个周期性的公式为原来的反复的微分方程介绍明确的分析解决方案,并且给在力量函数形式的一些特别解决方案什么时候=0。
简介:ThispaperdealswiththeexistenceandmultiplicityofperiodicsolutionsofDuffingequationsx+g(x)=p(t),TheauthorprovesaninfinityofperiodicsolutionstotheperiodicallyforcednonlinearDuffingequationsprovidedthatg(z)satisfiesthegloballylipschitzianconditionandthetime-mappingsatisfiestheweakeroscillatingproperty.
简介:ONEXCHANGEALGORITHMFORNONLINEARBESTCHEBYSHEVAPPROXIMATIONWITH LGHCONDITIONXiongGuijing(熊规景);WeiDan(韦旦)(Inst.ofMath.Sci.,Chin....
简介:<正>BytheuseofMoseriterationandCampanatospaceestimate,theL~∞andC~αregularitygradientofsolutionsofnonlinearparabolicsystem(u~2)/(t)-▽(g|▽u|▽u~2)=0withnonstandardgrowthconditionsareobtainedunderthenaturalstructureconstraints.
简介:我们在三或四个尺寸空格与nonpositiveanisotropy常数为Landau-Lifshitz方程的非零Neumann起始边界的值问题建立存在和部分整齐的扩展结果。部分整齐被证明直到边界,这结果是对为Dirichlet问题或同类的Neumann问题的那些的重要补充。
简介:Inthispaper,westudyanddiscusstheexistenceofmultiplesolutionsofaclassofnon-linearellipticequationswithNeumannboundarycondition,andobtainatleastsevennon-trivialsolutionsinwhichtwoarepositive,twoarenegativeandthreearesign-changing.Thestudyofproblem(1.1):{-△u+αu=f(u),x∈Ω,x∈Ω,δu/δr=0,x∈δΩ,isbasedonthevariationalmethodsandcriticalpointtheory.Weformourconclusionbyusingthesub-supsolutionmethod,MountainPassTheoreminorderintervals,Leray-Schauderdegreetheoryandtheinvarianceofdecreasingflow.