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The reactivity of various 2-oxyallyl cations toward 2,2'-methylenedifuran (1b), 2,2'-(hydroxymethyl)difuran (1c), 2,2'-(trimethylsilylmethylene)difuran (1d), and di(2-furyl)methanone (1e) has been explored. Difuryl derivatives 1c, 1d, and le refused to und ...
We introduce a density-functional perturbational scheme based on ultrasoft pseudopotentials for calculating dielectric tensors of periodic systems. We obtain a variational functional for the second-order derivative of the energy with respect to an electric ...
A novel methodology for the analysis of derivatives pricing in incomplete markets is tested empirically. The methodology generates hedge ratios and derivatives prices. They are estimated from the correlation structure between the local co-movements of secu ...
We present a new family of two-dimensional and three-dimensional orthogonal wavelets which uses quincunx sampling. The orthogonal refinement filters have a simple analytical expression in the Fourier domain as a function of the order λ, which may be nonint ...
We propose to design the reduction operator of an image pyramid so as to minimize the approximation error in the lp-sense (not restricted to the usual p=2), where p can take non-integer values. The underlying image model is specified using shift- ...
We show that a multi-dimensional scaling function of order γ (possibly fractional) can always be represented as the convolution of a polyharmonic B-spline of order γ and a distribution with a bounded Fourier transform which has neither order nor smoothness ...
We describe a new family of scaling functions, the (α, τ)-fractional splines, which generate valid multiresolution analyses. These functions are characterized by two real parameters: α, which controls the width of the scaling functions; and τ, which specif ...
The purpose of this presentation is to describe a recent family of basis functions—the fractional B-splines—which appear to be intimately connected to fractional calculus. Among other properties, we show that they are the convolution kernels that link the ...
In this paper, we revisit wavelet theory starting from the representation of a scaling function as the convolution of a B-spline (the regular part of it) and a distribution (the irregular or residual part). This formulation leads to some new insights on wa ...
