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Related papers: Using fractional differentiation in astronomy

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With an exponentially increasing amount of astronomical data, the complexity and dimension of astronomical data are likewise growing rapidly. Extracting information from such data becomes a critical and challenging problem. For example,…

Astrophysics · Physics 2011-04-11 H. Zheng , Y. Zhang

In this article we would like to consider some approaches to non-integer integro-differentiations and its implementation in computer algebra system Wolfram Mathematics.

History and Overview · Mathematics 2024-08-29 O. I. Marichev , E. L. Shishkina

In many astrophysical systems, smoothly-varying large-scale variations coexist with small-scale fluctuations. For example, a large-scale velocity or density gradient can exist in molecular clouds that exhibit small-scale turbulence. In…

Instrumentation and Methods for Astrophysics · Physics 2017-10-20 Jungyeon Cho

The shapelets method for image analysis is based upon the decomposition of localised objects into a series of orthogonal components with convenient mathematical properties. We extend the "Cartesian shapelet" formalism from earlier work, and…

Astrophysics · Physics 2009-11-10 Richard Massey , Alexandre Refregier

I introduce a straightforward technique for the filtering of extended astronomical images into components of different spatial scales. For a positive original image, each component is positive definite, and the sum of all components equals…

Astrophysics · Physics 2009-10-31 Lawrence Rudnick

We describe our ongoing work on, and future plans for, searches in bulk matter for fractional charge elementary particles and very massive elementary particles. Our primary interest is in searching for such particles that may have been…

High Energy Physics - Experiment · Physics 2007-05-23 Martin L. Perl , Valerie Halyo , Peter C. Kim , Eric R. Lee , Irwin T. Lee , Dinesh Loomba

We present a generic algorithm for performing astronomical image registration and pointing refinement. The method is based on matching the positions and fluxes of available point sources in image overlap regions. This information is used to…

Astrophysics · Physics 2009-11-10 Frank J. Masci , David Makovoz , Mehrdad Moshir

The theory of fractional calculus in the complex plane was not built with a specific application in mind. The main obstacle to application was the difficulty with obtaining analytic continuations of fractional derivatives and integrals. It…

Classical Analysis and ODEs · Mathematics 2015-10-01 V. P. Gurarii

Astronomical images suffer a constant presence of multiple defects that are consequences of the intrinsic properties of the acquisition equipments, and atmospheric conditions. One of the most frequent defects in astronomical imaging is the…

Instrumentation and Methods for Astrophysics · Physics 2015-06-15 Simon Beckouche , Jean-Luc Starck , Jalal Fadili

Astronomical images often have regions with missing or unwanted information, such as bad pixels, bad columns, cosmic rays, masked objects, or residuals from imperfect model subtractions. In certain situations it can be essential, or…

Instrumentation and Methods for Astrophysics · Physics 2024-02-06 Pieter van Dokkum , Imad Pasha

It is demonstrated that non-constant kernel solution, that can fit the spatial variations of the kernel can be obtained with minimum computing time. The CPU cost required with this new extension of the image subtraction method is almost the…

Astrophysics · Physics 2007-05-23 C. Alard

Astrophysics and cosmology are rich with data. The advent of wide-area digital cameras on large aperture telescopes has led to ever more ambitious surveys of the sky. Data volumes of entire surveys a decade ago can now be acquired in a…

Instrumentation and Methods for Astrophysics · Physics 2017-04-18 Jan Kremer , Kristoffer Stensbo-Smidt , Fabian Gieseke , Kim Steenstrup Pedersen , Christian Igel

We discuss the use of galaxies to trace the large-scale structure of the universe and thereby to make cosmological inferences. We put special emphasis on our lack of knowledge about the relative distribution of galaxies and the dynamically…

Astrophysics · Physics 2007-05-23 Michael A. Strauss , Michael Blanton

Plasma fractals is a technique to generate random and realistic clouds, textures and terrains~-- traditionally using recursive subdivision. We demonstrate a new approach, based on iterative expansion. It gives a family of algorithms that…

Graphics · Computer Science 2022-12-26 Oleg Kiselyov , Toshihiro Nakayama

Semantic segmentation is a critical task in computer vision aiming to identify and classify individual pixels in an image, with numerous applications in for example autonomous driving and medical image analysis. However, semantic…

Computer Vision and Pattern Recognition · Computer Science 2024-11-18 Halil Ibrahim Aysel , Xiaohao Cai , Adam Prügel-Bennett

Photometric redshifts play an important role as a measure of distance for various cosmological topics. Spectroscopic redshifts are only available for a very limited number of objects but can be used for creating statistical models. A broad…

Instrumentation and Methods for Astrophysics · Physics 2016-08-30 Kai Lars Polsterer , Antonio D'Isanto , Fabian Gieseke

I discuss recent progress in dark matter searches, focusing in particular on how rigorous modeling the dark matter distribution in the Galaxy and in its satellite galaxies improves our interpretation of the limits on the annihilation and…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 Louis E. Strigari

Fourier transforms are ubiquitous mathematical tools in basic and applied sciences. We here report classical and quantum optical realizations of the discrete fractional Fourier transform, a generalization of the Fourier transform. In the…

We present an algorithm implemented in the astroalign Python module for image registration in astronomy. Our module does not rely on WCS information and instead matches 3-point asterisms (triangles) on the images to find the most accurate…

Instrumentation and Methods for Astrophysics · Physics 2020-05-25 Martin Beroiz , Juan B. Cabral , Bruno Sanchez

The fractional calculus of variations and fractional optimal control are generalizations of the corresponding classical theories, that allow problem modeling and formulations with arbitrary order derivatives and integrals. Because of the…

Optimization and Control · Mathematics 2013-12-17 Shakoor Pooseh
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