Search Results - "Valentin Keyantuo"

Fractional integration of imaginary order in vector-valued Hölder spaces by El-Mennaoui, Omar, Keyantuo, Valentin, Sani, Ahmed

“…We prove that the Riemann–Liouville semigroup of fractional integration in the little Hölder space lip 0 α ( [ 0 , 1 ] , X ) admits a boundary value on the…”
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Lp-Maximal Regularity for a Class of Degenerate Integro-differential Equations with Infinite Delay in Banach Spaces by Aparicio, Rafael, Keyantuo, Valentin

“…Using the theory of operator-valued Fourier multipliers, we establish characterizations for well-posedness of a large class of degenerate integro-differential…”
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Well-posedness of degenerate integro-differential equations in function spaces by Rafael Aparicio, Valentin Keyantuo

“…We use operator-valued Fourier multipliers to obtain characterizations for well-posedness of a large class of degenerate integro-differential equations of…”
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Asymptotic behavior of mild solutions for a class of abstract nonlinear difference equations of convolution type by Keyantuo, Valentin, Lizama, Carlos, Rueda, Silvia, Warma, Mahamadi

“…We prove the existence and uniqueness of a weighted pseudo asymptotically mild solution to the following class of abstract semilinear difference equations: u (…”
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Approximate and Mean Approximate Controllability Properties for Hilfer Time-Fractional Differential Equations by Aragones, Ernest, Keyantuo, Valentin, Warma, Mahamadi

“…We study the approximate and mean approximate controllability properties of fractional partial differential equations associated with the so-called Hilfer type…”
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Existence, regularity and representation of solutions of time fractional wave equations by Valentin Keyantuo, Carlos Lizama, Mahamadi Warma

“…We study the solvability of the fractional order inhomogeneous Cauchy problem $$ \mathbb{D}_t^\alpha u(t)=Au(t)+f(t), \quad t>0,\;1<\alpha\le 2, $$ where A is…”
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Spectral Criteria for Solvability of Boundary Value Problems and Positivity of Solutions of Time-Fractional Differential Equations by Keyantuo, Valentin, Lizama, Carlos, Warma, Mahamadi

“…We investigate mild solutions of the fractional order nonhomogeneous Cauchy problem Dtαu(t)=Au(t)+f(t),  t>0, where 0<α<1. When A is the generator of a…”
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L^p$$-Maximal Regularity for a Class of Degenerate Integro-differential Equations with Infinite Delay in Banach Spaces by Aparicio, Rafael, Keyantuo, Valentin

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Besov maximal regularity for a class of degenerate integro‐differential equations with infinite delay in Banach spaces by Aparicio, Rafael, Keyantuo, Valentin

“…The theory of operator‐valued Fourier multipliers is used to obtain characterizations for well‐posedness of a large class of degenerate integro‐differential…”
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Maximal Regularity for a Class of Degenerate Integro-differential Equations with Infinite Delay in Banach Spaces by Aparicio, Rafael, Keyantuo, Valentin

“…Using the theory of operator-valued Fourier multipliers, we establish characterizations for well-posedness of a large class of degenerate integro-differential…”
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Cyclic sequences of periodic sums in βN by Keyantuo, Valentin, Zelenyuk, Yevhen, Zelenyuk, Yuliya

“…Let m≥2 and n≥2 and define ν:ω→{0,…,m−1} by ν(k)≡k(modm). We show that there is a sequence p0,…,pm−1 in βN such that all sums ∑j=ikpν(j), where i∈{0,…,m−1} and…”
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A Characterization of Uniform Well Posedness for Degenerate Second-Order Abstract Differential Equations by Aparicio, Rafael, Keyantuo, Valentin, Lizama, Carlos

“…We completely characterize the uniform well-posedness of the Dirichlet boundary value problem for degenerate second order abstract differential equations in…”
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The Wave Equation in Lp-Spaces by Keyantuo, Valentin, Warma, Mahamadi

“…In the first part of the paper, Gaussian estimates are used to study $L^p$-summability of the solution of the wave equation in $L^p(\Omega)$ associated with a…”
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Lattice Dynamical Systems Associated with a Fractional Laplacian by Keyantuo, Valentin, Lizama, Carlos, Warma, Mahamadi

“…We derive optimal well-posedness results and explicit representations of solutions in terms of special functions for the linearized version of the equation for…”
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Right ideal decompositions of G by Keyantuo, Valentin, Zelenyuk, Yevhen

“…Let G be an infinite discrete group, let βG be the Stone–Čech compactification of G, and let G⁎=βG∖G. We show that if G can be embedded algebraically in a…”
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Entire regularizations of strongly continuous groups and products of analytic generators by Cioranescu, Ioana, Keyantuo, Valentin

“…Using entire regularizations of C_0-groups, we give a characterization of their analytic generators which we apply to the study of products of such generators…”
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Fractional Gaussian estimates and holomorphy of semigroups by Keyantuo, Valentin, Seoanes, Fabian, Warma, Mahamadi

“…Let Ω ⊂ R N be an arbitrary open set, 0 < s < 1 and denote by ( e - t ( - Δ ) R N s ) t ≥ 0 the semigroup on L 2 ( R N ) generated by the fractional Laplace…”
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A characterization of periodic solutions for time-fractional differential equations in UMD spaces and applications by Keyantuo, Valentin, Lizama, Carlos

“…We study the fractional differential equation (*) Dαu(t) + BDβu(t) + Au(t) = f(t),  0 ⩽ t ⩽ 2π (0 ⩽ β < α ⩽ 2) in periodic Lebesgue spaces Lp(0,  2π; X) where…”
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Well-posedness results for a class of semi-linear super-diffusive equations 24 by Alvarez, Edgardo, Gal, Ciprian G, Keyantuo, Valentin, Warma, Mahamadi

“…In this paper we investigate the following fractional order in time Cauchy problem ... The fractional in time derivative is taken in the classical Caputo…”
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Discrete subsets and convergent sequences in topological groups by Keyantuo, Valentin, Zelenyuk, Yevhen

“…We show that (1) assuming there is no rapid ultrafilter, every countable nondiscrete maximally almost periodic topological group contains a discrete nonclosed…”
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