Results 21 to 30 of about 21,050 (203)
Some New Notions of Bases for the Range of Operators in Hilbert Spaces [PDF]
Sahand Communications in Mathematical AnalysisThis paper is devoted to introduce a new concept of bases for the range of the operator $K$. Actually, we consider controlled $K$-orthonormal and controlled $K$-Riesz bases which are a generalization of ordinary bases in Hilbert spaces. In the sequel, we
Hessam Hosseinnezhad
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On the Basis Property of the Root Functions of Some Class of Non-self-adjoint Sturm--Liouville Operators [PDF]
, 2013 We obtain the asymptotic formulas for the eigenvalues and eigenfunctions of the Sturm-Liouville operators with some regular boundary conditions. Using these formulas, we find sufficient conditions on the potential q such that the root functions of these ...
Nur, Cemile, Veliev, O. A.
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Riesz Basicity for General Systems of Functions
Journal of Function Spaces, 2014 In this paper we find the general conditions for a complete biorthogonal conjugate system to form a Riesz basis. We show that if a complete biorthogonal conjugate system is uniformly bounded and its coefficient space is solid, then the system forms a ...
A. M. Sarsenbi, P. A. Terekhin
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A New Approach to Continuous Riesz Bases [PDF]
Journal of Sciences, Islamic Republic of Iran, 2013 This paper deals with continuous frames and continuous Riesz bases. We introduce continuous Riesz bases and give some equivalent conditions for a continuous frame to be a continuous Riesz basis.
A.A. Arefijamaal +3 more
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Comment on “Continuous g-Frame in Hilbert -Modules”
Abstract and Applied Analysis, 2013 The continuous g-frames in Hilbert -modules were introduced and investigated by Kouchi and Nazari (2011). They also studied the continuous g-Riesz basis and a characterization for it was presented by using the synthesis operator. However, we found that
Zhong-Qi Xiang
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Riesz bases and positive operators on Hilbert space
International Journal of Mathematics and Mathematical Sciences, 2003 It is shown that a normalized Riesz basis for a Hilbert space H (i.e., the isomorphic image of an orthonormal basis in H) induces in a natural way a new, but equivalent, inner product on H in which it is an orthonormal basis, thereby extending the sense ...
James R. Holub
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Uniform Convergence of the Spectral Expansion for a Differential Operator with Periodic Matrix Coefficients [PDF]
, 2007 In this paper, we obtain asymptotic formulas for eigenvalues and eigenfunctions of the operator generated by a system of ordinary differential equations with summable coefficients and the quasiperiodic boundary conditions. Using these asymptotic formulas,
Veliev, O. A.
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Adaptive Riesz Basis Decomposition For Image Search
, 2009 Publication in the conference proceedings of EUSIPCO, Glasgow, Scotland ...
Capodiferro L +4 more
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Journal of Applied Mathematics, 2013 We introduce the modular continuous g-Riesz basis to improve one existing result for continuous g-Riesz basis in Hilbert -modules, and then we study the equivalency relations between continuous g-frames in Hilbert -modules, and, in particular, we obtain ...
Zhong-Qi Xiang
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Three problems on exponential bases
, 2018 We consider three special and significant cases of the following problem. Let D be a (possibly unbounded) set of finite Lebesgue measure in R^d. Find conditions on D for which the standard exponential basis on the unit cube of R^d is a frame, a Riesz ...
De Carli, Laura +2 more
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