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In this paper we address the uncertainty issues involved in the low-level vision task of image segmentation. Researchers in computer vision have worked extensively on this problem, in which the goal is to partition (or segment) an image…

Artificial Intelligence · Computer Science 2013-03-08 Steven M. LaValle , Seth A. Hutchinson

Rapid growth in the field of quantitative digital image analysis is paving the way for researchers to make precise measurements about objects in an image. To compute quantities from the image such as the density of compressed materials or…

Computer Vision and Pattern Recognition · Computer Science 2017-07-31 Marylesa Howard , Margaret C. Hock , B. T. Meehan , Leora Dresselhaus-Cooper

X-ray parametric down-conversion is a fundamental nonlinear effect that promises a wide range of possible applications. Nevertheless, it has been scarcely investigated and unequivocal evidence of the effect is still missing for certain…

The often debated issue of `ratios of small numbers of events' is approached from a probabilistic perspective, making a clear distinction between the predictive problem (forecasting numbers of events we might count under well stated…

Methodology · Statistics 2020-12-09 Giulio D'Agostini

Photon branching ratios are critical input data for activities such as nuclear materials protection and accounting because they allow material compositions to be extracted from measurements of gamma-ray intensities. Uncertainties in these…

A new method of the phase determination in X-ray crystallography is proposed. The method is based on the so-called "minimum charge" principle, recently suggested by Elser. The electron density function $\rho$ is sought in the form…

Condensed Matter · Physics 2018-09-28 P. Kalugin

A framework for the interpretation of the spectral states of black hole X-ray transients based on the diversity of accretion disk models is introduced. Depending on the mass accretion rate, it is proposed that the accretion disk is…

Astrophysics · Physics 2009-10-28 Xingming Chen , Ronald E. Taam

Quantum state tomography aims to determine the state of a quantum system as represented by a density matrix. It is a fundamental task in modern scientific studies involving quantum systems. In this paper, we study estimation of…

Statistics Theory · Mathematics 2016-03-25 Tony Cai , Donggyu Kim , Yazhen Wang , Ming Yuan , Harrison H. Zhou

The power-law emission and reflection component provide valuable insights into the accretion process around a black hole. In this work, thanks to the broadband spectra coverage of \emph{the Nuclear Spectroscopic Telescope Array}, we study…

High Energy Astrophysical Phenomena · Physics 2023-03-15 Bei You , Yanting Dong , Zhen Yan , Zhu Liu , Youli Tuo , Yuanle Yao , Xinwu Cao

We describe how the coherence function, a Fourier frequency-dependent measure of the linear correlation between time series measured simultaneously in two energy channels, can be used in conjunction with energy spectra, power spectra, and…

Astrophysics · Physics 2009-10-28 Brian A. Vaughan , Michael A. Nowak

Absorption spectroscopy is routinely used to characterise chemical and biological samples. For the state-of-the-art in absorption spectroscopy, precision is theoretically limited by shot-noise due to the fundamental Poisson-distribution of…

X-ray emission spectroscopy is a well-established technique used to study continuum lowering in dense plasmas. It relies on accurate atomic physics models to robustly reproduce high-resolution emission spectra, and depends on our ability to…

Plasma Physics · Physics 2020-01-22 M. F. Kasim , J. S. Wark , S. M. Vinko

Measuring low light absorption with combined uncertainty < 1 permille is crucial in a wide range of applications. Popular cavity ring-down spectroscopy can provide ultra-high precision, below 0.01 permille, but its accuracy is strongly…

Estimating the quality of a single-photon source is crucial for its use in quantum technologies. The standard test for semiconductor sources is a value of the second-order correlation function of the emitted field below $1/2$ at zero…

Quantum Physics · Physics 2020-05-12 Jorge Rolando Chavez-Mackay , Peter Grünwald , Blas Manuel Rodríguez-Lara

Density ratio estimation in high dimensions can be reframed as integrating a certain quantity, the time score, over probability paths which interpolate between the two densities. In practice, the time score has to be estimated based on…

Machine Learning · Computer Science 2025-06-13 Hanlin Yu , Arto Klami , Aapo Hyvärinen , Anna Korba , Omar Chehab

Spot density is commonly used as an indication of shower energy in emulsion chambers. In a system originally developed for JACEE analysis, the optical density of a spot on x-ray film is estimated from macroscopic digital images. The spot's…

Astrophysics · Physics 2007-05-23 E. L. Zager , R. J. Wilkes , J. J. Lord

We revisit here how Raman spectroscopy can be used to estimate the H content in hard hydrogenated amorphous carbon layers. The H content was varied from 2 at.% to 30 at.%, using heat treatments of a a-C:H, from room temperature to 1300 K…

Materials Science · Physics 2013-08-22 Cedric Pardanaud , C. Martin , P. Roubin , G. Giacometti , C. Hopf , T. Schwarz-Selinger , W. Jacob

As a general rule of thumb the resolution of a light microscope (i.e. the ability to discern objects) is predominantly described by the full width at half maximum (FWHM) of its point spread function (psf)---the diameter of the blurring…

Statistics Theory · Mathematics 2020-10-23 Gytis Kulaitis , Axel Munk , Frank Werner

In a macroscopic realm, in which photons are too many for being counted by any photon counting detector, photon statistics can be measured by using detectors simply endowed with linear response. We insert one of such detectors in a…

Quantum Physics · Physics 2009-06-16 Alessandra Andreoni , Maria Bondani

Progress in high-resolution x-ray microtomography has provided us with a practical approach to determining three-dimensional (3D) structures of opaque samples at micrometer to submicrometer resolution. In this review, we give an…

Biological Physics · Physics 2016-09-09 Ryuta Mizutani , Yoshio Suzuki