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The Enhanced Resolution Imager and Spectrograph (ERIS) is the new near-infrared instrument at the VLT-UT4. ERIS replaces and extends the observational capabilities formerly provided by SINFONI and NACO: integral field spectroscopy at 1 -…

Symmetry detection and morphological classification of anatomical structures play pivotal roles in medical image analysis. The application of kinematic surface fitting, a method for characterizing shapes through parametric stationary…

Computer Vision and Pattern Recognition · Computer Science 2024-01-30 Wilhelm Wimmer , Hervé Delingette

The baseline contrast floor from the Roman Coronagraph's High-Order Wavefront Sensing and Control strategy likely degrades over the course of time, requiring periodic recalibration of the dark hole. Here, we propose to consider spatial…

Instrumentation and Methods for Astrophysics · Physics 2025-09-12 Thayne Currie , Olivier Guyon , Ruslan Belikov , Dan Sirbu , Mona El Morsy

This work presents an algorithmic scheme for solving the infinite-time constrained linear quadratic regulation problem. We employ an accelerated version of a popular proximal gradient scheme, commonly known as the Forward-Backward Splitting…

Optimization and Control · Mathematics 2015-01-20 Giorgos Stathopoulos , Milan Korda , Colin N. Jones

Except for a few specific types, cardiac arrhythmias are not immediately life-threatening. However, if not treated appropriately, they can cause serious complications. In particular, atrial fibrillation, which is characterized by fast and…

Machine Learning · Computer Science 2020-10-08 Jérôme Van Zaen , Ricard Delgado-Gonzalo , Damien Ferrario Mathieu Lemay

Direct imaging and spectral characterization of exoplanets using extreme adaptive optics (ExAO) is a key science goal of future extremely large telescopes and space observatories. However, quasi-static wavefront errors will limit the…

Instrumentation and Methods for Astrophysics · Physics 2018-08-29 Benjamin L. Gerard , Christian Marois , Raphaël Galicher

Diffeomorphic image registration is a commonly used method to deform one image to resemble another. While warping a single image to another is useful, it can be advantageous to warp multiple images simultaneously, such as in tracking the…

Computer Vision and Pattern Recognition · Computer Science 2024-03-26 Sean Rendell , Jinming Duan

High-precision ground-based observations of the inner corona (1.05-2.0 R_sun) are fundamentally constrained by instrumental stray light, particularly the additive background from dynamic dust accumulation on the objective lens. To address…

Solar and Stellar Astrophysics · Physics 2026-05-14 Xiande Liu , Xuefei Zhang , Yu Liu , Tengfei Song , Mingyu Zhao , Mingzhe Sun , Feiyang Sha , Jun Fang

Direct imaging of exoplanet systems requires the use of coronagraphs to reach high contrast levels (10^-8 to 10^-11) at small angular separations (0.1"). However, the performance of these devices is drastically limited by aberrations (in…

Instrumentation and Methods for Astrophysics · Physics 2017-10-11 Johan Mazoyer , Raphaël Galicher , Pierre Baudoz , Patrick Lanzoni , Frédéric Zamkotsian , Gérard Rousset

The problem of maneuvering a vehicle through a race course in minimum time requires computation of both longitudinal (brake and throttle) and lateral (steering wheel) control inputs. Unfortunately, solving the resulting nonlinear optimal…

Robotics · Computer Science 2019-02-05 Nitin R. Kapania , John Subosits , J Christian Gerdes

Feature tracking Cardiac Magnetic Resonance (CMR) has recently emerged as an area of interest for quantification of regional cardiac function from balanced, steady state free precession (SSFP) cine sequences. However, currently available…

Computer Vision and Pattern Recognition · Computer Science 2017-04-13 Davis M. Vigneault , Weidi Xie , David A. Bluemke , J. Alison Noble

Direct exoplanet imaging via coronagraphy requires maintenance of high contrast in a dark hole for lengthy integration periods. Wavefront errors that change slowly over that time accumulate and cause systematic errors in the star's Point…

Instrumentation and Methods for Astrophysics · Physics 2019-03-08 Leonid Pogorelyuk , N. Jeremy Kasdin

Three-photon (3P) microscopy is getting traction due to its superior performance in deep tissues. Yet, aberrations and light scattering still pose one of the main limitations in the attainable depth ranges for high-resolution imaging. Here,…

Second-generation exoplanet imagers using extreme adaptive optics and coronagraphy have demonstrated their great potential for studying close circumstellar environments and for detecting new companions and helping to understand their…

Instrumentation and Methods for Astrophysics · Physics 2019-08-28 A. Vigan , M. N'Diaye , K. Dohlen , J. -F. Sauvage , J. Milli , G. Zins , C. Petit , Z. Wahhaj , F. Cantalloube , A. Caillat , A. Costille , J. Le Merrer , A. Carlotti , J. -L. Beuzit , D. Mouillet

We propose a high-contrast coronagraph for direct imaging of young Jupiter-like planets orbiting nearby bright stars. The coronagraph employs a step-transmission filter in which the intensity is apodized with a finite number of steps of…

Instrumentation and Methods for Astrophysics · Physics 2015-05-14 Jiangpei Dou , Deqing Ren , Yongtian Zhu

A low out-degree orientation directs each edge of an undirected graph with the goal of minimizing the maximum out-degree of a vertex. In the parallel batch-dynamic setting, one can insert or delete batches of edges, and the goal is to…

Distributed, Parallel, and Cluster Computing · Computer Science 2026-02-23 Guy Blelloch , Andrew Brady , Laxman Dhulipala , Jeremy Fineman , Kishen Gowda , Chase Hutton

A new wavefront sensing approach, derived from the successful curvature wavefront sensing concept but using a non-linear phase retrieval wavefront reconstruction scheme, is described. The non-linear curvature wavefront sensor (nlCWFS)…

Instrumentation and Methods for Astrophysics · Physics 2015-05-14 Olivier Guyon

Generally, wave field reconstructions obtained by phase-retrieval algorithms are noisy, blurred and corrupted by various artifacts such as irregular waves, spots, etc. These disturbances, arising due to many factors such as non-idealities…

Optics · Physics 2012-07-24 Artem Migukin , Mostafa Agour , Vladimir Katkovnik

Exoplanet detection and characterization through extreme adaptive optics (ExAO) is a key science goal of future extremely large telescopes. This achievement, however, will be limited in sensitivity by both quasi-static wavefront errors and…

Earth and Planetary Astrophysics · Physics 2018-07-18 Benjamin L. Gerard , Christian Marois , Raphaël Galicher , Jean-Pierre Véran

Phase aberration is an inherent side effect of ultrasound imaging due to the speed of sound inhomogeneity nature of human tissues, resulting in focusing error and reduced image contrast. This work introduces a phase aberration correction…

Signal Processing · Electrical Eng. & Systems 2023-08-29 Wei-Hsiang Shen , Yu-An Lin , Pai-Chi Li , Meng-Lin Li
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