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Unsupervised anomaly localization on industrial textured images has achieved remarkable results through reconstruction-based methods, yet existing approaches based on image reconstruction and feature reconstruc-tion each have their own…

Computer Vision and Pattern Recognition · Computer Science 2024-07-26 Shichen Qu , Xian Tao , Zhen Qu , Xinyi Gong , Zhengtao Zhang , Mukesh Prasad

Accurate flood water mapping is critical for disaster management, yet current methods struggle to fully exploit the potential of spaceborne imagery. Optical data offers high interpretability but is limited by environmental conditions,…

Computer Vision and Pattern Recognition · Computer Science 2026-05-05 Jagrati Talreja , Tewodros Syum Gebre , Leila Hashemi-Beni

We develop a prescription for characterizing the strengths of metal lines associated with Lyman-alpha forest absorbers (LYFAs) of a given neutral hydrogen column density N_HI and metallicity [Fe/H]. This Line Observability Index (LOX) is…

Astrophysics · Physics 2009-10-30 Uffe Hellsten , Lars Hernquist , Neal Katz , David Weinberg

Optical interferometers provide multiple wavelength measurements. In order to fully exploit the spectral and spatial resolution of these instruments, new algorithms for image reconstruction have to be developed. Early attempts to deal with…

Instrumentation and Methods for Astrophysics · Physics 2015-06-11 Éric Thiébaut , Ferréol Soulez , Loïc Denis

We calibrate here cosmological radiative transfer simulation with ATON/RAMSES with a range of measurements of the Lyman alpha opacity from QSO absorption spectra. We find the Lyman alpha opacity to be very sensitive to the exact timing of…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-23 Jonathan Chardin , Martin G. Haehnelt , Dominique Aubert , Ewald Puchwein

We present the first detection of a correlation between the Lyman-$\alpha$ forest and cosmic microwave background (CMB) lensing. For each Lyman-$\alpha$ forest in SDSS-III/BOSS DR12, we correlate the one-dimensional power spectrum with the…

Cosmology and Nongalactic Astrophysics · Physics 2016-11-15 Cyrille Doux , Emmanuel Schaan , Eric Aubourg , Ken Ganga , Khee-Gan Lee , David N. Spergel , Julien Tréguer

Accurate 3D reconstruction of colored objects with structured light (SL) is hindered by lateral chromatic aberration (LCA) in optical components and uneven noise characteristics across RGB channels. This paper introduces lateral chromatic…

Computer Vision and Pattern Recognition · Computer Science 2026-03-12 Wonbeen Oh , Jae-Sang Hyun

Estimates of Omega_baryon from primordial nucleosynthesis together with standard assumptions about the ionization state of low column density Lyman alpha forest clouds can be used to determine an upper limit for the cloud thickness along…

Astrophysics · Physics 2016-06-08 Michael Rauch , Martin G. Haehnelt

Lyman alpha absorber correlations contain information about the underlying density distribution associated with a particular class of absorbers. As such, they provide an opportunity to independently measure the "bias" of the Lyman alpha…

Astrophysics · Physics 2016-01-27 Romeel Davé , Neal Katz , David H. Weinberg

Recent numerical simulations have lead to a paradigm shift in our understanding of the intergalactic medium, and the loss of a physical justification for Voigt profile fitting of the Lyman-alpha forest. Many individual lines seen in…

Astrophysics · Physics 2009-10-31 P. J. Outram , R. F. Carswell , T. Theuns

The Lyman-$\alpha$ absorption spectrum associated with photons traversing the intergalactic medium allows us to probe the linear matter power spectrum down to relatively small distance scales. Finding ways of accurately evaluating…

Cosmology and Nongalactic Astrophysics · Physics 2023-01-04 Keith R. Dienes , Fei Huang , Jeff Kost , Brooks Thomas , Hai-Bo Yu

We measure the intergalactic medium (IGM) opacity in the Ly$\alpha$ as well as in the Ly$\beta$ forest along $19$ quasar sightlines between $5.5\lesssim z_{\rm abs}\lesssim 6.1$, probing the end stages of the reionization epoch. Owing to…

Astrophysics of Galaxies · Physics 2019-08-14 Anna-Christina Eilers , Joseph F. Hennawi , Frederick B. Davies , Jose Oñorbe

We report new measurements of the intergalactic medium (IGM) Ly$\alpha$ and Ly$\beta$ effective optical depth at $5.3<z<6.5$, using a new sample of quasar sightlines including 32 quasars at $6.308\le z\le7.00$. These quasars provide a large…

To enhance the resolution of a confocal laser scanning microscope the additional information of a pinhole plane image taken at every excitation scan position can be used [C. J. R. Sheppard, Super-resolution in confocal imaging, Optik 80,…

Optics · Physics 2013-06-27 Stephan Roth , Colin J. R. Sheppard , Kai Wicker , Rainer Heintzmann

In optical tomography a physical body is illuminated with near-infrared light and the resulting outward photon flux is measured at the object boundary. The goal is to reconstruct internal optical properties of the body, such as absorption…

Numerical Analysis · Mathematics 2016-01-20 Antti Hannukainen , Lauri Harhanen , Nuutti Hyvönen , Helle Majander

We present a model for the Lyman-alpha absorbers that treats all objects (from the low-density forest clouds to the dense damped systems) in a unified description. This approach is consistent with an earlier model of galaxies (luminosity…

Astrophysics · Physics 2007-05-23 P. Valageas , R. Schaeffer , J. Silk

Purpose: 3D Time-of-flight (TOF) MR Angiography (MRA) can accurately visualize the intracranial vasculature, but is limited by long acquisition times. Compressed sensing (CS) reconstruction can be used to substantially accelerate…

Medical Physics · Physics 2021-04-12 Matthijs H. S. de Buck , Peter Jezzard , Aaron T. Hess

The Lyman $\alpha$ (Ly$\alpha$) line from high-redshift galaxies is a powerful probe of the Epoch of Reionization (EoR). Neutral hydrogen in the intergalactic medium (IGM) can significantly attenuate the emergent Ly$\alpha$ line, even in…

Astrophysics of Galaxies · Physics 2026-02-17 Samuel Gagnon-Hartman , Andrei Mesinger , Ivan Nikolić , Eleonora Parlanti , Giacomo Venturi

Low-dose computed tomography (LDCT) aims to minimize the radiation exposure to patients while maintaining diagnostic image quality. However, traditional CT reconstruction algorithms often struggle with the ill-posed nature of the problem,…

Image and Video Processing · Electrical Eng. & Systems 2024-10-17 Daisy Chen

Likelihood-based deep generative models have been widely investigated for Image Anomaly Detection (IAD), particularly Normalizing Flows, yet their strict architectural invertibility needs often constrain scalability, particularly in…

Computer Vision and Pattern Recognition · Computer Science 2026-04-15 Liangwei Li , Lin Liu , Hanzhe Liang , Juanxiu Liu , Jing Zhang , Ruqian Hao , Xiaohui Du , Yong Liu , Pan Li
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