Results 1 to 10 of about 42 (41)
Structure of the tree component in an area of riparian forest in the Piratini River Basin, Rio Grande do Sul, Brazil [PDF]
Biotemas, 2009 The vegetation studied belongs to the Pampa biome. The vegetation of this region is described as Open Arboreal Savanna because it presents a herb stratum and an arboreal stratum with a gallery forest.
Luciano Rodrigues Soares +1 more
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Global Perturbation of Nonlinear Eigenvalues
Advanced Nonlinear Studies, 2021 This paper generalizes the classical theory of perturbation of eigenvalues up to cover the most general setting where the operator surface 𝔏:[a,b]×[c,d]→Φ0(U,V){\mathfrak{L}:[a,b]\times[c,d]\to\Phi_{0}(U,V)}, (λ,μ)↦𝔏(λ,μ){(\lambda,\mu)\mapsto\mathfrak ...
López-Gómez Julián +1 more
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Generalized lower characteristic involving measures of non-strict singularity
Topological Algebra and its Applications, 2023 This work establishes a connection between the class of generalized lower characteristic operators and [⋅]a{\left[\cdot ]}_{a} acting on a Banach space involving measures of non-strict singularity.
Baraket Sami +2 more
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On (m, P)-expansive operators: products, perturbation by nilpotents, Drazin invertibility
Concrete Operators, 2021 A generalisation of m-expansive Hilbert space operators T ∈ B(ℋ) [18, 20] to Banach space operators T ∈ B(𝒳) is obtained by defining that a pair of operators A, B ∈ B(𝒳) is (m, P)-expansive for some operator P ∈ B(𝒳) if Δ A,Bm(P)= (I-LARB)m(P)=∑j=0m(-1)j(
Duggal B.P.
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Structure of n-quasi left m-invertible and related classes of operators
Demonstratio Mathematica, 2020 Given Hilbert space operators T,S∈B(ℋ)T,S\in B( {\mathcal H} ), let Δ\text{Δ} and δ∈B(B(ℋ))\delta \in B(B( {\mathcal H} )) denote the elementary operators ΔT,S(X)=(LTRS−I)(X)=TXS−X{\text{Δ}}_{T,S}(X)=({L}_{T}{R}_{S}-I)(X)=TXS-X and δT,S(X)=(
Duggal Bhagwati Prashad, Kim In Hyun
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Spectrum perturbations of compact operators in a Banach space
Open Mathematics, 2019 For an integer p ≥ 1, let Γp be an approximative quasi-normed ideal of compact operators in a Banach space with a quasi-norm NΓp(.) and the ...
Gil’ Michael
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Pairs of closed geodesics in metric graphs
Demonstratio MathematicaIn this paper we study the counting pairs of closed geodesics on metric graphs. We obtain an asymptotic for the number of pairs of closed geodesics ordered by their word lengths on the metric graph, such that the difference of their geometric lengths ...
Saif Al Abri Al Jalila
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Demonstratio MathematicaIf T1{{\mathbb{T}}}_{1} and T2{{\mathbb{T}}}_{2} are commuting dd-tuples of Hilbert space operators in B(ℋ)dB{\left({\mathcal{ {\mathcal H} }})}^{d} such that (T1*⊗I+I⊗T2*,T1⊗I+I⊗T2)\left({{\mathbb{T}}}_{1}^{* }\otimes I+I\otimes {{\mathbb{T}}}_{2}^{* },{
Duggal Bhagwati Prashad, Kim In Hyoun
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Approximation of eigenvalues for unbounded Jacobi matrices using finite submatrices
Open Mathematics, 2014 Monvel Anne, Zielinski Lech
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