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Related papers: Inversions in astronomy and the SOLA method

200 papers

The main goal of this paper is to estimate the regional acoustic and geoacoustic shallow-water environment from data collected by a vertical hydrophone array and transmitted by distant time-harmonic point sources. We aim at estimating the…

Analysis of PDEs · Mathematics 2019-09-04 Laure Dumaz , Josselin Garnier , Guilhem Lepoultier

Ultrasound modulated optical tomography, also called acousto-optics tomography, is a hybrid imaging modality that aims to combine the high contrast of optical waves with the high resolution of ultrasound. We follow the model of the…

Analysis of PDEs · Mathematics 2015-06-15 Guillaume Bal , Shari Moskow

In this paper, an unrolling algorithm of the iterative subspace-based optimization method (SOM) is proposed for solving full-wave inverse scattering problems (ISPs). The unrolling network, named SOM-Net, inherently embeds the Lippmann-…

Signal Processing · Electrical Eng. & Systems 2022-12-07 Yu Liu , Hao Zhao , Rencheng Song , Xudong Chen , Chang Li , Xun Chen

Ultrasound modulated bioluminescence tomography (UMBLT) is an imaging method which can be formulated as a hybrid inverse source problem. In the regime where light propagation is modeled by a radiative transfer equation, previous approaches…

Analysis of PDEs · Mathematics 2020-08-14 Francis Chung , Tianyu Yang , Yang Yang

In this paper, we propose novel methods to increase total luminosity and decrease error propagation during subluminal or luminal interstellar transits by navigation with star maps. We demonstrate with theoretical and simulation models in…

General Physics · Physics 2023-02-03 Nghi C. Nguyen

In helioseismology, there is a well-known offset between observed and computed oscillation frequencies. This offset is known to arise from improper modeling of the near-surface layers of the Sun, and a similar effect must occur for models…

Astrophysics · Physics 2009-11-13 Hans Kjeldsen , Timothy R. Bedding , Joergen Christensen-Dalsgaard

Inversion of operators is a fundamental concept in data processing. Inversion of linear operators is well studied, supported by established theory. When an inverse either does not exist or is not unique, generalized inverses are used. Most…

Statistics Theory · Mathematics 2024-04-02 Eyal Gofer , Guy Gilboa

Photon transport through a diffusing slab can be described by the radiative transfer equation (RTE). When the slab is highly scattering and weakly absorbing, the RTE simplifies to the diffusion equation. In this paper, an inverse diffusion…

In this paper we propose accelerated gradient descent schemes for convex optimization problems in Hilbert space. We consider inexact oracle case.

Optimization and Control · Mathematics 2019-10-16 Alexander Gasnikov , Sergey Kabanikhin , Ahmed Mohammed , Maxim Shishlenin

Although the standard cosmological model is capable of explaining most current observational data, it faces some theoretical and observational issues. This is the main motivation for exploring alternative cosmological models. In this paper,…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-05 Matías Leizerovich , Luisa G. Jaime , Susana J. Landau , Gustavo Arciniega

The ELM method has become widely used for classification and regressions problems as a result of its accuracy, simplicity and ease of use. The solution of the hidden layer weights by means of a matrix pseudoinverse operation is a…

Neural and Evolutionary Computing · Computer Science 2014-06-02 André van Schaik , Jonathan Tapson

A common problem in the sciences is that a signal of interest is observed only indirectly, through smooth functionals of the signal whose values are then obscured by noise. In such inverse problems, the functionals dampen or entirely…

Methodology · Statistics 2012-07-04 Darren Homrighausen , Christopher R. Genovese

Inverse problems are ubiquitous in the sciences and engineering. Two categories of inverse problems concerning a physical system are (1) estimate parameters in a model of the system from observed input-output pairs and (2) given a model of…

Methodology · Statistics 2023-12-05 Faaiq G. Waqar , Swati Patel , Cory M. Simon

After extensively explored, broad agreement between observations and theories has been reached that satellites are preferentially aligned with major axes of their host centrals. There are still some issues unsolved on this topic. In this…

Astrophysics of Galaxies · Physics 2020-04-29 Lin Tang , Weipeng Lin , Yang Wang

This paper addresses the inverse scattering problem in the domain Omega. The input data, measured outside Omega, involve the waves generated by the interaction of plane waves with various directions and unknown scatterers fully occluded…

Numerical Analysis · Mathematics 2024-06-25 Phuong M. Nguyen , Loc H. Nguyen , Huong T. T. Vu

Helioseismic inversions reveal a major discrepancy in sound speed between the Sun and the standard solar model just below the base of solar convection zone. We demonstrate that this discrepancy is caused by the inherent shortcomings of the…

Solar and Stellar Astrophysics · Physics 2012-10-17 Chunguang Zhang , Licai Deng , Darun Xiong , Jørgen Christensen-Dalsgaard

We present, using a novel technique, a study of the angular distribution of satellite galaxies around a sample of isolated, blue host galaxies selected from the sixth data release of the Sloan Digital Sky Survey. As a complement to previous…

Astrophysics · Physics 2008-11-26 Jason H. Steffen , Octavio Valenzuela

This paper analyses the relativistic stellar aberration requirements for the Space Interferometry Mission (SIM). We address the issue of general relativistic deflection of light by the massive self-gravitating bodies. Specifically, we…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Slava G. Turyshev

This review provides an introduction to - and overview of - the current state of the art in neural-network based regularization methods for inverse problems in imaging. It aims to introduce readers with a solid knowledge in applied…

Optimization and Control · Mathematics 2023-12-25 Andreas Habring , Martin Holler

Images from adaptive optics systems are generally affected by significant distortions of the point spread function (PSF) across the field of view, depending on the position of natural and artificial guide stars. Image reduction techniques…

Instrumentation and Methods for Astrophysics · Physics 2015-06-24 Andrea La Camera , Laura Schreiber , Emiliano Diolaiti , Patrizia Boccacci , Mario Bertero , Michele Bellazzini , Paolo Ciliegi