Search Results - "Constantin Buse"

Hyers–Ulam stability and discrete dichotomy by Barbu, Dorel, Buşe, Constantin, Tabassum, Afshan

“…Let m be a given positive integer and let A be an m×m complex matrix. We prove that the discrete systemXn+1=AXn,n∈Z+ is Hyers–Ulam stable if and only if the…”
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Hyers–Ulam stability and discrete dichotomy for difference periodic systems by Buşe, Constantin, O'Regan, Donal, Saierli, Olivia, Tabassum, Afshan

“…Denote by Z+ the set of all nonnegative integer numbers. Let An be an m×m invertible q-periodic complex matrix, for all n∈Z+ and some positive integers m and…”
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Hyers-Ulam Stability for Linear Differences with Time Dependent and Periodic Coefficients by Buşe, Constantin, O’Regan, Donal, Saierli, Olivia

“…Let q ≥ 2 be a positive integer and let ( a j ) , ( b j ) , and ( c j ) (with j a non-negative integer) be three given C -valued and q-periodic sequences. Let…”
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Hyers-Ulam Stability for Linear Differences with Time Dependent and Periodic Coefficients: The Case When the Monodromy Matrix Has Simple Eigenvalues by Buşe, Constantin, O’Regan, Donal, Saierli, Olivia

“…Let q ≥ 2 be a positive integer and let ( a j ) , ( b j ) and ( c j ) (with j nonnegative integer) be three given C -valued and q-periodic sequences. Let A ( q…”
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Global and local versions for a Phong Vu theorem for periodic evolution families in Hilbert spaces by Constantin Buse, Lan Thanh Nguyen, Donal O'Regan

“…A theorem of Gearhart concerning strongly continuous semigroups in Hilbert spaces is extremely useful for stability analysis of concrete equations; see e.g…”
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A surjection problem leading to the Ax-Grothendieck theorem by Buşe, Constantin, O'Regan, Donal, Saierli, Olivia

“…We give a complete functional calculus for matrices of order two. The key tools are two simple Lemmas (Lemma 2.1 and Lemma 2.2, below), which are elementary…”
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Exponential stability for solutions of continuous and discrete abstract Cauchy problems in Banach spaces by Constantin Buse, Toka Diagana, Lan Thanh Nguyen, Donal O'Regan

“…Let T be a strongly continuous semigroup acting on a complex Banach space X and let A be its infinitesimal generator. It is well-known [29,33] that the uniform…”
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An inequality concerning the growth bound of a discrete evolution family on a complex Banach space by Buşe, Constantin, O'Regan, Donal, Saierli, Olivia

“…We prove that the uniform growth bound of a discrete evolution family of bounded linear operators acting on a complex Banach space X satisfies the inequality…”
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Hyers-Ulam stability and exponential dichotomy of linear differential periodic systems are equivalent by Buşe, Constantin, Barbu, Dorel, Tabassum, Afshan

“…Let $m$ be a positive integer and $q$ be a positive real number. We prove that the $m$-dimensional and $q$-periodic system \begin{equation}\tag{$\ast$} \dot…”
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Connections between exponential stability and boundedness of solutions of a couple of differential time depending and periodic systems by Arshad, Sadia, Buse, Constantin, Saierli, Olivia

“…Among others, we prove that the vectorial time dependent $q$-periodic differential system $$\dot x(t)=A(t)x(t),\quad t\in\mathbb{R}, \quad…”
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An inequality concerning the growth bound of an evolution family and the norm of a convolution operator by Buşe, Constantin, O’Regan, Donal, Saierli, Olivia

“…Let U = { U ( t , s ) } t ≥ s ≥ 0 be a strongly continuous and exponentially bounded evolution family acting on a complex Banach space X and let X be a certain…”
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Asymptotic stability and uniform boundedness with respect to parameters for discrete non-autonomous periodic systems by Barbu, Dorel, Buşe, Constantin

“…Let X be a complex Banach space and q ≥ 2 be a fixed integer number. Let be a q-periodic discrete evolution family generated by the ℒ(X)-valued, q-periodic…”
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Spectral characterizations for Hyers-Ulam stability by Buse, Constantin, Saierli, Olivia, Tabassum, Afshan

“…First we prove that an $n\times n$ complex linear system is Hyers-Ulam stable if and only if it is dichotomic (i.e. its associated matrix has no eigenvalues on…”
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Weak Rolewicz's theorem in Hilbert spaces by Constantin Buse, Gul Rahmat

“…Let $phi:mathbb{R}_+:=[0, infty)o mathbb{R}_+$ be a nondecreasing function which is positive on $(0, infty)$ and let $mathcal{U} ={U(t, s)}_{tge sge 0}$ be a…”
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Weak real integral characterizations for exponential stability of semigroups in reflexive spaces by Buşe, Constantin, Khan, Aftab, Rahmat, Gul, Saierli, Olivia

“…Let ( t n ) be a sequence of nonnegative real numbers tending to ∞, such that 1≤ t n +1 − t n ≤ α for all natural numbers n and some positive α . We prove that…”
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Asymptotic behavior of discrete evolution families in Banach spaces by Buşe, Constantin, Khan, Aftab, Nguyen, Lan T., O'Regan, Donal, Rahmat, Gul

“…Let X be a Banach space, be an operator-valued sequence and let be the discrete evolution family associated to In this paper we prove that the family is…”
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Uniform exponential stability for discrete non-autonomous systems via discrete evolution semigroups by Buşe, Constantin, Khan, Aftab, Rahmat, Gul, Tabassum, Afshan

“…We prove that a discrete evolution family U = {U(m i n)}m≥n∊ℤ+ of bounded linear operators acting on a complex Banach space X is uniformly exponentially stable…”
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Stability for trajectories of periodic evolution families in Hilbert spaces by Dorel Barbu, Joel Blot, Constantin Buse, Olivia Saierli

“…Let $q$ be a positive real number and let $A(\cdot)$ be a $q$-periodic linear operator valued function on a complex Hilbert space $H$, and let $D$ be a dense…”
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Norm inequalities of Čebyšev type for power series in Banach algebras by Dragomir, Silvestru S, Boldea, Marius V, Buşe, Constantin, Megan, Mihail

“…Let f ( λ ) = ∑ n = 0 ∞ α n λ n be a function defined by power series with complex coefficients and convergent on the open disk D ( 0 , R ) ⊂ C , R > 0 and x ,…”
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Exponential Stability and Uniform Boundedness of Solutions for Nonautonomous Periodic Abstract Cauchy Problems. An Evolution Semigroup Approach by Buşe, Constantin, Lassoued, Dhaou, Nguyen, Thanh Lan, Saierli, Olivia

“…Let u μ, x , s (., 0) be the solution of the following well-posed inhomogeneous Cauchy Problem on a complex Banach space X Here, x is a vector in X ,  μ is a…”
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