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Related papers: Fourier transforms on Cantor sets: A study in non-…

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We present a general theory of fractal transformations and show how it leads to a new type of method for filtering and transforming digital images. This work substantially generalizes earlier work on fractal tops. The approach involves…

Geometric Topology · Mathematics 2011-02-17 Michael F. Barnsley , Brendan Harding , Konstantin Igudesman

Recently, there has been an increasing interest in the study of hypercomplex signals and their Fourier transforms. This paper aims to study such integral transforms from general principles, using 4 different yet equivalent definitions of…

Classical Analysis and ODEs · Mathematics 2011-01-11 H. De Bie , N. De Schepper , F. Sommen

The Fourier transform is typically seen as closely related to the additive group of real numbers, its characters and its Haar measure. In this paper, we propose an alternative viewpoint; the Fourier transform can be uniquely characterized…

Functional Analysis · Mathematics 2024-06-11 Cameron L. Williams , Bernhard G. Bodmann , Donald J. Kouri

This paper determines how to define a discretely implemented Fourier transform when analysing an observed spatial point process. To develop this transform we answer four questions; first what is the natural definition of a Fourier…

Methodology · Statistics 2023-06-08 Tuomas A. Rajala , Sofia C. Olhede , Jake P. Grainger , David J. Murrell

In this note, we study the convergence from the discrete to the continuous non-linear Fourier transform. Relations between spectral problems and questions in complex function theory provide a new approach to the study of scattering problems…

Classical Analysis and ODEs · Mathematics 2024-08-16 Ashley R. Zhang

In this paper, we give a review of fractal calculus which is an expansion of standard calculus. Fractal calculus is applied for functions which are not differentiable or integrable on totally disconnected fractal sets such as middle-$\mu$…

Dynamical Systems · Mathematics 2019-11-05 Cemil Tunc , Alireza Khalili Golmankhaneh

We consider an optical diffraction grating in which the spatial distribution of open slits forms a fractal set. The Fraunhofer diffraction patterns through the fractal grating are obtained analytically for the simplest triad Cantor type and…

Optics · Physics 2007-05-23 Dongsu Bak , Sang Pyo Kim , Sung Ku Kim , Kwang-Sup Soh , Jae Hyung Yee

In this paper, we prove some new thickness theorems with partial derivatives. We give some applications. First, we give a simple criterion that can judge whether two scaled Cantor sets have non-empty intersection. Second, we prove under…

Dynamical Systems · Mathematics 2022-12-02 Kan Jiang

In this contribution we generalize the classical Fourier Mellin transform [S. Dorrode and F. Ghorbel, Robust and efficient Fourier-Mellin transform approximations for gray-level image reconstruction and complete invariant description,…

Rings and Algebras · Mathematics 2013-06-10 Eckhard Hitzer

As a generalization of the Fourier transform, the fractional Fourier transform was introduced and has been further investigated both in theory and in applications of signal processing. We obtain a sampling theorem on shift-invariant spaces…

Functional Analysis · Mathematics 2013-02-12 Sinuk Kang

This report will explore and answer fundamental questions about taking Fourier Transforms and tying it with recent advances in AI and neural architecture. One interpretation of the Fourier Transform is decomposing a signal into its…

Sound · Computer Science 2023-08-22 Prateek Verma

We revisit the Fourier transform of a Hankel function, of considerable importance in the theory of knife edge diffraction. Our approach is based directly upon the underlying Bessel equation, which admits manipulation into an alternate…

General Mathematics · Mathematics 2021-12-21 J. A. Grzesik

The quaternion Fourier transform (QFT), a generalization of the classical 2D Fourier transform, plays an increasingly active role in particular signal and colour image processing. There tends to be an inordinate degree of interest placed on…

Classical Analysis and ODEs · Mathematics 2019-03-04 Dong Cheng , Kit Ian Kou

An experiment to demonstrate the Fourier transform of an electric signal using the Kundt's tube is described. The results of finding the component frequencies and an approximation to the amplitudes of two sinusoidal signals which compose an…

Physics Education · Physics 2016-03-31 Srijit Paul , Mahesh Gandikota

The classical Fourier transform is, in essence, a way to take data and extract components (in the form of complex exponentials) which are invariant under cyclic shifts. We consider a case in which the components must instead be invariant…

Representation Theory · Mathematics 2014-06-26 Nathaniel Eldredge

We introduce the notion of boundary representation for fractal Fourier expansions, starting with a familiar notion of spectral pairs for affine fractal measures. Specializing to one dimension, we establish boundary representations for these…

Functional Analysis · Mathematics 2010-08-24 Dorin Ervin Dutkay , Palle E. T. Jorgensen

We propose a discrete fractional random transform based on a generalization of the discrete fractional Fourier transform with an intrinsic randomness. Such discrete fractional random transform inheres excellent mathematical properties of…

Mathematical Physics · Physics 2007-05-23 Zhengjun Liu , Haifa Zhao , Shutian Liu

The nonlinear Fourier transform (NFT), a powerful tool in soliton theory and exactly solvable models, is a method for solving integrable partial differential equations governing wave propagation in certain nonlinear media. The NFT…

Information Theory · Computer Science 2014-10-09 Mansoor I. Yousefi , Frank R. Kschischang

We establish properties of a new type of fractal which has partial self similarity at all scales. For any collection of iterated functions systems with an associated probability distribution and any positive integer V there is a…

Dynamical Systems · Mathematics 2008-02-04 Michael Barnsley , John E. Hutchinson , Örjan Stenflo

A set of semi-analytical techniques based on Fourier analysis is used to solve wave scattering problems in variously shaped waveguides with varying normal admittance boundary conditions. Key components are newly developed conformal mapping…

Mathematical Physics · Physics 2015-06-02 Anders Andersson , Borje Nilsson , Thomas Biro