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Structured-light 3D scanners create 3D models with high accuracy, but controlling the accuracy and repeatability of the scanner is essential. The objective of this paper is to analyze the repeatability and accuracy of two structured-light…

Image and Video Processing · Electrical Eng. & Systems 2019-10-30 María-Eugenia Polo , Aurora Cuartero , Ángel M. Felicísimo

Purpose: The purpose of this work is to develop a new approach for high spatial resolution dosimetry based on Raman micro-spectroscopy scanning of radiochromic film (RCF). We generate dose calibration curves over an extended dose range from…

Medical Physics · Physics 2021-09-15 Connor Mcnairn , Iymad Mansour , Bryan Muir , Rowan M. Thomson , Sangeeta Murugkar

Encoding information about continuous variables using noisy computational units is a challenge; nonetheless, asymptotic theory shows that combining multiple periodic scales for coding can be highly precise despite the corrupting influence…

Neurons and Cognition · Quantitative Biology 2013-08-22 Alexander Mathis , Andreas V. M. Herz , Martin B. Stemmler

We derive general equations for non-linearity corrections and statistical uncertainty (variance) estimates for data acquired with near-infrared detectors employing correlated double sampling, multiple correlated double sampling (Fowler…

Astrophysics · Physics 2009-11-10 W. D. Vacca , M. C. Cushing , J. T. Rayner

The purpose of this study was to find the most accurate model for radiochromic film dosimetry by comparing different channel independent perturbation models. A model selection approach based on (algorithmic) information theory was followed,…

Medical Physics · Physics 2015-05-05 Ignasi Méndez

Gravitational lens modeling of spatially resolved sources is a challenging inverse problem with many observational constraints and model parameters. We examine established pixel-based source reconstruction algorithms for de-lensing the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 Amitpal Tagore , Charles Keeton

Context. The scattering polarization signal observed in the photospheric Sr i 4607 {\AA} line is expected to vary at granular spatial scales. This variation can be due to changes in the magnetic field intensity and orientation (Hanle…

Solar and Stellar Astrophysics · Physics 2018-06-20 M. Bianda , S. Berdyugina , D. Gisler , R. Ramelli , L. Belluzzi , E. S. Carlin , J. O. Stenflo , T. Berkefeld

We present a quantitative study of coherent array imaging of remote sources in randomly perturbed waveguides with bounded cross-section. We study how long range cumulative scattering by perturbations of the boundary and the medium impedes…

Numerical Analysis · Mathematics 2013-06-10 Liliana Borcea , Josselin Garnier , Chrysoula Tsogka

This work analyzes the RAID dataset to evaluate human responses to affine image distortions, including rotation, translation, scaling, and Gaussian noise. Using Mean Squared Error (MSE), the study establishes human detection thresholds for…

Background: The aim of this study was to assess the robustness of cardiac SPECT radiomics features against changes in imaging settings including acquisition and reconstruction settings. Methods: Four scanners were used to acquire SPECT…

We study the noise of the intensity variance and of the intensity correlation and structure functions measured in light scattering from a random medium in the case when these quantities are obtained by averaging over a finite number N of…

What spatial frequency information do humans and neural networks use to recognize objects? In neuroscience, critical band masking is an established tool that can reveal the frequency-selective filters used for object recognition. Critical…

Machine Learning · Computer Science 2023-11-07 Ajay Subramanian , Elena Sizikova , Najib J. Majaj , Denis G. Pelli

Photometric redshift uncertainties are a major source of systematic error for ongoing and future photometric surveys. We study different sources of redshift error caused by choosing a suboptimal redshift histogram bin width and propose…

Cosmology and Nongalactic Astrophysics · Physics 2017-05-02 Markus Michael Rau , Ben Hoyle , Kerstin Paech , Stella Seitz

The main objective of multichannel radiochromic film dosimetry methods is to correct, or at least mitigate, spatial heterogeneities in the film-scanner response, especially variations in the active layer thickness. To this end, films can…

Medical Physics · Physics 2018-09-20 I. Méndez , A. Polšak , R. Hudej , B. Casar

Random telegraph noise (RTN) is a major contributor to read noise in many CMOS image sensors considered for astronomical use. While scientific CMOS image sensors deliver lower read noise than traditional charge-coupled devices, mitigating…

Instrumentation and Methods for Astrophysics · Physics 2026-05-20 Christopher Layden , Daniel-Rolf Harbeck , Tejus Deo-Dixit , Nathan Lourie , Gabor Furesz , Kevin Burdge

The paper presents an alternative way to classical stereocorrelation. First, 2D image processing of random patterns is described. Sub-pixel displacements are determined using phase analysis. Then distortion evaluation is presented. The…

Classical Physics · Physics 2013-11-18 Jérôme Molimard , Gaetan Boyer , Hassan Zahouani

Some aspects of the systematic and statistical errors affecting grid-based estimation of stellar masses and radii have still not been investigated well. We study the impact on mass and radius determination of the uncertainty in the input…

Solar and Stellar Astrophysics · Physics 2015-06-18 G. Valle , M. Dell'Omodarme , P. G. Prada Moroni , S. Degl'Innocenti

Reverberation chambers (RCs) were recently reported as a low-cost alternative to anechoic chambers (ACs) to perform radar cross-section (RCS) pattern measurements. The method consists of using transmitting and receiving antennas pointing…

Graphical analysis methods are widely used in positron emission tomography quantification because of their simplicity and model independence. But they may, particularly for reversible kinetics, lead to bias in the estimated parameters. The…

Quantitative Methods · Quantitative Biology 2009-04-20 Hongbin Guo , Rosemary A Renaut , Kewei Chen , Eric M Reiman

We study array imaging of a sparse scene of point-like sources or scatterers in a homogeneous medium. For source imaging the sensors in the array are receivers that collect measurements of the wave field. For imaging scatterers the array…

Numerical Analysis · Mathematics 2015-07-03 Liliana Borcea , Ilker Kocyigit
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