Weyl Fractional Operator Research Articles

Fractional calculus for distributions

AbstractFractional derivatives and integrals for measures and distributions are reviewed. The focus is on domains and co-domains for translation invariant fractional operators. Fractional derivatives and integrals interpreted as "Equation missing"-convolution operators with power law kernels are found to have the largest domains of definition. As a result, extending domains from functions to distributions via convolution operators contributes to far reaching unifications of many previously existing definitions of fractional integrals and derivatives. Weyl fractional operators are thereby extended to distributions using the method of adjoints. In addition, discretized fractional calculus and fractional calculus of periodic distributions can both be formulated and understood in terms of "Equation missing"-convolution.

The periodic response of a fractional oscillator with a spring-pot and an inerter-pot

Abstract The fractional oscillation system with two Weyl-type fractional derivative terms $_{ - \infty }D_t^\beta x$ (0 < β < 1) and $_{ - \infty }D_t^\alpha x$ (1 < α < 2), which portray a “spring-pot” and an “inerter-pot” and contribute to viscoelasticity and viscous inertia, respectively, was considered. At first, it was proved that the fractional system with constant coefficients under harmonic excitation is equivalent to a second-order differential system with frequency-dependent coefficients by applying the Fourier transform. The effect of the fractional orders β (0 < β < 1) and α (1 < α < 2) on inertia, stiffness and damping was investigated. Then, the harmonic response of the fractional oscillation system and the corresponding amplitude–frequency and phase–frequency characteristics were deduced. Finally, the steady-state response to a general periodic incentive was obtained by utilizing the Fourier series and the principle of superposition, and the numerical examples were exhibited to verify the method. The results show that the Weyl fractional operator is extremely applicable for researching the steady-state problem, and the fractional derivative is capable of describing viscoelasticity and portraying a “spring-pot”, and also describing viscous inertia and serving as an “inerter-pot”.

The best constants for multidimensional modular inequalities over spherical cones

In this paper, we establish the Muckenhoupt-type estimation for the best constant associated with the following multidimensional modular inequality over a spherical cone:where and . Similar results are also derived for the complementary integral operator. Our results provide the -dimensional modular forms of the works of Andersen and Heinig. As consequences of our results, we give the -dimensional weighted extensions of Levinson modular inequality, extensions of Stepanov and Heinig results, generalizations of the Hardy–Knopp-type inequalities, and those for the Riemann–Liouville operator and the Weyl fractional operator. We also point out that our estimates are better than those given in the works of Drabek, Heinig, Kunfer, and Sinnamon.

A note on the multidimensional Weyl fractional operator

The purpose of the present paper is to establish a connection theorem involving the multidimensional Weyl fractional operator and the classical multidimensional Laplace transform. This provides an extension of a result due to Raina and Koul [6].