共查询到20条相似文献,搜索用时 78 毫秒
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§0. IntroductionLetLbeacollectionofclosedsubspacesofaHilbertspaceHcontaining{0}andHwhichformsacompletesubspacelatticeundertheoperations∧(intersection)and∨(closedlinearspan).WedenotebyalgLthealgebraofallboundedlinearoperatorswhichleaveallsubspacesinLi… 相似文献
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§1. IntroductionIn[1,2],AronsonandWeinbergerhavestudiedsystematiclythescalarnonlineardiffu-sionequationinonespacevariableut=uxx+φ(u),(1.1)whereu=u(x,t)andφ(u)isanonlinearfunction.Equation(1.1)arisesinseveralapplica-tions;See[1,2]and[3]forinformationa… 相似文献
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A Property of Solutions for Elliptic Equation with Nonstandard Growth Conditions in Unbounded Domain
§0. IntroductionLetΩbeanunboundeddomaininthen-dimensionalEuclideanspaceEn(n3).Consider-ingthefollowingellipticequationwithnonstandardgrowthconditions:-divA(x,u,u)=B(x,u,u)(1)whereA(x,u,ξ)={Ai(x,u,ξ),i=1,2,…,n}andB(x,u,ξ)aredefinedonEn×E1×En,con-… 相似文献
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§1.IntroductionTheTeichmülerspacesdiscussedinthispaperareinfinitedimensionalTeichmülerspaceswithcomplexstructure.Thisimpliest... 相似文献
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AbstractLetMbearealhypersurfacewiththree.distinctconstantprincipalcur-vaturesintwodimensionalcomplexhyperbolicspaceCH,theneither(a)Mhastwoprincipalcurvatureswhosedifferenceislargethanzeroandlessthanone.(b)ThethreeprincipalcurvaturesofMformanequidifferencesequencewhosecommondifferenceisone;(c)Misholomorphiccongruenttoanopenpartofatubearoundrealtwodimentionalhyperbolicspace..Keywords.Realhypersurfacecomplexhyperbolicspacetubelequidifferencesequence 相似文献
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§0.IntroductionWewriteFP(n)forCP(n)(n-dimensionalcomplexprojectivespace)orHP(n)(n-di-mensionalquaternionicprojectivespace).Mn... 相似文献
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OntheOrderofBestApproximationbyPolynomialsinH■SpacesXingFuchong(邢富冲)(CentralUniversityforNationalities,Beijing,100081)Communi... 相似文献
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2-HarmonicTotallyRealSubmanifoldsinaComplex Projective SpaceSunHongan(孙弘安)(SouthernInstituteofMetallurgy)Abstract:Inthispaper... 相似文献
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LetfbealinearmappingfromaBanachspaceXtoaBanachspaceY.Thentheseparatingspaceoffis(f)={y∈Y:thereexistsasequence(xn)inXwithxn0a... 相似文献
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LetXbeaspace ,andQatopologicalproperty .Ifforeachx∈X ,thereexistsaneighborhoodUofxsuchthatUhaspropertyQ ,thenwecallXalocalQ space . Definition 1 AspaceXiscalledθ refinable,ifforeveryopencoverUofXthereexistsasequence {Un}ofopenrefinementsofUsuchthatforeachx∈X ,… 相似文献
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We study the behaviour of sequences \(U_2^n X U_1^{-n}\), where \(U_1, U_2\) are unitary operators, whose spectral measures are singular with respect to the Lebesgue measure, and the commutator \(XU_1-U_2X\) is small in a sense. The conjecture about the weak averaged convergence of the difference \(U_2^n X U_1^{-n}-U_2^{-n} X U_1^n\) to the zero operator is discussed and its connection with complex-symmetric operators is established in a general situation. For a model case where \(U_1=U_2\) is the unitary operator of multiplication by z on \(L^2(\mu )\), sufficient conditions for the convergence as in the Conjecture are given in terms of kernels of integral operators. 相似文献
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算子的拟相似与(Q)类算子 总被引:1,自引:2,他引:1
本文引进定义于L(H)上的集值函数β(S)和(Q)类算子(指本质谱含于其一切拟相似算子的本质谱的算子),用β(S)刻划 (Q)类算子的特征;证明(Q)类算子范围广泛,次可分解算子(包括次标量算子,M-亚正常算子,半亚正常算子等等)是其中的一部分;(Q)类算子在L(H)中稠密. 相似文献
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C. AparicioA.R. Villena 《Journal of Functional Analysis》2002,196(1):155-161
Let G be a locally compact abelian group, let μ be a bounded complex-valued Borel measure on G, and let Tμ be the corresponding convolution operator on L1(G). Let X be a Banach space and let S be a continuous linear operator on X. Then we show that every linear operator Φ: X→L1(G) such that ΦS=TμΦ is continuous if and only if the pair (S,Tμ) has no critical eigenvalue. 相似文献
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Related to a semigroup of operators on a metric measure space, we define and study pseudodifferential operators (including the setting of Riemannian manifolds, fractals, graphs etc.). Boundedness on L p for pseudodifferential operators of order 0 is proved. We mainly focus on symbols belonging to the class $S^{0}_{1,\delta}$ for δ∈[0,1). For the limit class $S^{0}_{1,1}$ , we describe some results by restricting our attention to the case of a sub-Laplacian operator on a Riemannian manifold. 相似文献
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Götz E. Pfander 《Journal of Fourier Analysis and Applications》2013,19(3):612-650
Sampling and reconstruction of functions is a fundamental tool in science. We develop an analogous sampling theory for operators whose Kohn-Nirenberg symbols are bandlimited. We prove sampling theorems for in this sense bandlimited operators and show that our results generalize both, the classical sampling theorem, and the fact that a time-invariant operator is fully determined by its impulse response. 相似文献
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Mediterranean Journal of Mathematics - We introduce a family of differential-reflection operators $${\Lambda_{A, \varepsilon}}$$ acting on smooth functions defined on $${{\mathbb R}}$$ . Here, A is... 相似文献
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Karim Nour 《Mathematical Logic Quarterly》1998,44(1):99-108
In 1990, J. L. Krivine introduced the notion of storage operator to simulate, for Church integers, the “call by value” in a context of a “call by name” strategy. In the present paper we define for every λ-term S which realizes the successor function on Church integers the notion of S-storage operator. We prove that every storage operator is an S-storage operator. But the converse is not always true. 相似文献
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We introduce the notion of spectralizable operators. A closed operator A in a Hilbert space is called spectralizable if there exists a non-constant polynomial p such that the operator p(A) is a scalar spectral operator in the sense of Dunford. We show that such operators belongs to the class of generalized spectral
operators and give some examples where spectralizable operators occur naturally.
Vladimir Strauss gratefully acknowledges support by DFG, Grant No. TR 903/3-1. 相似文献