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Related papers: Wavelet methods in multi-conjugate adaptive optics

200 papers

Many-objective evolutionary algorithms (MOEAs), especially the decomposition-based MOEAs, have attracted wide attention in recent years. Recent studies show that a well designed combination of the decomposition method and the domination…

Neural and Evolutionary Computing · Computer Science 2019-09-05 Yingyu Zhang , Yuanzhen Li , Quan-Ke Panb , P. N. Suganthan

In order to increase the corrected field of view of an adaptive optics (AO) system, several deformable mirrors (DM) have to be placed in the conjugate planes of the dominant turbulent layers (multi-conjugate adaptive optics, MCAO [Beckers…

Astrophysics · Physics 2022-04-20 T. Berkefeld , A. Glindemann , S. Hippler

This paper considers the reconstruction problem in Acousto-Electrical Tomography, i.e., the problem of estimating a spatially varying conductivity in a bounded domain from measurements of the internal power densities resulting from…

Numerical Analysis · Mathematics 2020-01-13 Simon Hubmer , Kim Knudsen , Changyou Li , Ekaterina Sherina

Real-time satellite imaging has a central role in monitoring, detecting and estimating the intensity of key natural phenomena such as floods, earthquakes, etc. One important constraint of satellite imaging is the trade-off between…

Image and Video Processing · Electrical Eng. & Systems 2023-01-09 Haoqing Li , Bhavya Duvvuri , Ricardo Borsoi , Tales Imbiriba , Edward Beighley , Deniz Erdogmus , Pau Closas

We analyze the mathematical model of multiwave tomography with a variable speed with integrating measurements on planes tangent to a sphere surrounding the source. We prove sharp uniqueness and stability estimates with full and partial data…

Analysis of PDEs · Mathematics 2016-05-04 Plamen Stefanov , Yang Yang

Multi-conjugate adaptive optics (MCAO) will assist a new era of ground-based astronomical observations with the extremely large telescopes and the Very Large Telescope. High precision relative astrometry is among the main science drivers of…

Instrumentation and Methods for Astrophysics · Physics 2022-09-05 Giulia Carlà , Cédric Plantet , Lorenzo Busoni , Guido Agapito

Ray optics is an intuitive and computationally efficient model for wave propagation through nonuniform media. However, the underlying geometrical-optics (GO) approximation of ray optics breaks down at caustics, erroneously predicting the…

Optics · Physics 2022-10-10 Nicolas A. Lopez

In the framework of a 4m class Solar Telescope we studied the performance of the MCAO using the LOST simulation package. In particular, in this work we focus on two different methods to reduce the time delay error which is particularly…

Instrumentation and Methods for Astrophysics · Physics 2015-05-19 Marco Stangalini , Francesco Berrilli , Dario Del Moro , Roberto Piazzesi

The Multiconjugate Adaptive Optics RelaY (MAORY) is and Adaptive Optics module to be mounted on the ESO European-Extremely Large Telescope (E-ELT). It is a hybrid Natural and Laser Guide System that will perform the correction of the…

In this paper, we consider the classical wave equation with time-dependent, spatially multiscale coefficients. We propose a fully discrete computational multiscale method in the spirit of the localized orthogonal decomposition in space with…

Numerical Analysis · Mathematics 2021-07-30 Bernhard Maier , Barbara Verfürth

The conjugate gradient method is a widely used algorithm for the numerical solution of a system of linear equations. It is particularly attractive because it allows one to take advantage of sparse matrices and produces (in case of infinite…

Numerical Analysis · Mathematics 2017-11-27 Sergey Voronin , Christophe Zaroli , Naresh P. Cuntoor

In this work we develop and analyze an adaptive finite element method for efficiently solving electrical impedance tomography -- a severely ill-posed nonlinear inverse problem for recovering the conductivity from boundary voltage…

Numerical Analysis · Mathematics 2019-05-16 Bangti Jin , Yifeng Xu , Jun Zou

The direct imaging of potentially habitable Exoplanets is one prime science case for the next generation of high contrast imaging instruments on ground-based extremely large telescopes. To reach this demanding science goal, the instruments…

MAVIS (the MCAO-Assisted Visible Imager and Spectrograph), planned for the VLT Adaptive Optics Facility, represents an innovative step in Multi-Conjugate Adaptive Optics (MCAO) systems, particularly in its operation at visible wavelengths…

Collimated beam ultrasound systems are a novel technology for imaging inside multi-layered structures such as geothermal wells. Such systems include a transmitter and multiple receivers to capture reflected signals. Common algorithms for…

Image and Video Processing · Electrical Eng. & Systems 2022-02-22 Abdulrahman Alanazi , Singanallur Venkatakrishnan , Hector Santos-Villalobos , Gregery Buzzard , Charles Bouman

Modern image-based object detection models, such as YOLOv7, primarily process individual frames independently, thus ignoring valuable temporal context naturally present in videos. Meanwhile, existing video-based detection methods often…

Computer Vision and Pattern Recognition · Computer Science 2025-06-26 Yitong Quan , Benjamin Kiefer , Martin Messmer , Andreas Zell

Adaptive optics is a technique mostly used on large telescopes. It turns out to be challenging for smaller telescopes (0.5~2m) due to the small isoplanatic angle, small subapertures and high correction speeds needed at visible wavelengths,…

Instrumentation and Methods for Astrophysics · Physics 2023-10-12 Olivier Lai , Mark Chun , Stefan Kuiper , Niek Doelman , Marcel Carbillet , Mamadou N'Diaye , Frantz Martinache , Lyu Abe , Jean-Pierre Rivet , Dirk Schmidt

This paper focuses on the acousto-electromagnetic tomography, a recently introduced hybrid imaging technique. In a previous work, the reconstruction of the electric permittivity of the medium from internal data was achieved under the Born…

Analysis of PDEs · Mathematics 2019-04-04 Giovanni S. Alberti , Habib Ammari , Kaixi Ruan

We propose a novel compressed sensing method to improve the depth reconstruction accuracy and multi-target separation capability of indirect Time-of-Flight (iToF) systems. Unlike traditional approaches that rely on hardware modifications,…

Signal Processing · Electrical Eng. & Systems 2025-07-29 Yansong Du , Yutong Deng , Yuting Zhou , Feiyu Jiao , Bangyao Wang , Zhancong Xu , Zhaoxiang Jiang , Xun Guan

We derive computed tomography (CT) of a time-varying volumetric translucent object, using a small number of moving cameras. We particularly focus on passive scattering tomography, which is a non-linear problem. We demonstrate the approach…

Computer Vision and Pattern Recognition · Computer Science 2020-12-08 Roi Ronen , Yoav Y. Schechner , Eshkol Eytan