Criteria of strong type two-weighted inequalities for fractional maximal functions.
Criteria of weighted inequalities in Orlicz classes for maximal functions defined on homogeneous type spaces.
Criterion on Lp-boundedness for a class of oscillatory singular integrals with rough kernels.
Critical imbeddings with multivariate rearrangements
We are concerned with imbeddings of general spaces of Besov and Lizorkin-Triebel type with dominating mixed derivatives in the first critical case. We employ multivariate exponential Orlicz and Lorentz-Orlicz spaces as targets. We study basic properties of the target spaces, in particular, we compare them with usual exponential spaces, showing that in this case the multivariate clones are in fact better adapted to the character of smoothness of the imbedded spaces. Then we prove sharp limiting imbedding...
Critical length for a Beurling type theorem
In a recent paper [3] C. Baiocchi, V. Komornik and P. Loreti obtained a generalisation of Parseval's identity by means of divided differences. We give here a proof of the optimality of that theorem.
Curriculum vita of Prof. Vasil Atanasov Popov
Our primary goal in this preamble is to highlight the best of Vasil Popov’s mathematical achievements and ideas. V. Popov showed his extraordinary talent for mathematics in his early papers in the (typically Bulgarian) area of approximation in the Hausdorff metric. His results in this area are very well presented in the monograph of his advisor Bl. Sendov, “Hausdorff Approximation”.
Cyclic subspaces for unitary representations of LCA groups; generalized Zak transform
We just published a paper showing that the properties of the shift invariant spaces, ⟨f⟩, generated by the translates by ℤⁿ of an f in L²(ℝⁿ) correspond to the properties of the spaces L²(𝕋ⁿ,p), where the weight p equals [f̂,f̂]. This correspondence helps us produce many new properties of the spaces ⟨f⟩. In this paper we extend this method to the case where the role of ℤⁿ is taken over by locally compact abelian groups G, L²(ℝⁿ) is replaced by a separable Hilbert space on which a unitary representation...
Damping oscillatory integrals.
Damping oscillatory integrals with polynomial phase.
Darstellung temperierter vektorwertiger Distributionen durch holomorphe Funktionen II.
Das Verhalten der Greenschen Matrix und der Entwicklungen nach Eigenfunktionen N-regulärer Eigenwertprobleme.
Daubechies wavelets on intervals with application to BVPs
In this paper, Daubechies wavelets on intervals are investigated. An analytic technique for evaluating various types of integrals containing the scaling functions is proposed; they are compared with classical techniques. Finally, these results are applied to two-point boundary value problems.
De l'analyse de Fourier à l'analyse harmonique
Decay of Fourier transforms and summability of eigenfunction expansions
Decomposition systems for function spaces
Let be a decomposition system for indexed over D, the set of dyadic cubes in , and a finite set E, and let be the corresponding dual functionals. That is, for every , . We study sufficient conditions on Θ,Θ̃ so that they constitute a decomposition system for Triebel-Lizorkin and Besov spaces. Moreover, these conditions allow us to characterize the membership of a distribution f in these spaces by the size of the coefficients , e ∈ E, I ∈ D. Typical examples of such decomposition systems...
Decreasing Rearranged Fourier Series.
Degree of approximation of conjugate of a function belonging to Lip class by matrix summability means of conjugate Fourier series.
Degree of Best Approximation by Trigonometric Blending Functions.
Démonstration probabiliste de certaines inégalités de Littlewood-Paley. Exposé I : les inégalités classiques
Démonstration probabiliste de certaines inégalités de Littlewood-Paley. Exposé II : l'opérateur carré du champ