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An image or volume of interest in positron emission tomography (PET) is reconstructed from pairs of gamma rays emitted from a radioactive substance. Many image reconstruction methods are based on estimation of pixels or voxels on some…

Signal Processing · Electrical Eng. & Systems 2019-06-18 Azra Tafro , Damir Seršić , Ana Sović Kržić

In this paper, a methodology is investigated for signal recovery in the presence of non-Gaussian noise. In contrast with regularized minimization approaches often adopted in the literature, in our algorithm the regularization parameter is…

Optimization and Control · Mathematics 2017-01-23 Yosra Marnissi , Yuling Zheng , Emilie Chouzenoux , Jean-Christophe Pesquet

Schlieren imaging is an optical technique to observe the flow of transparent media, such as air or water, without any particle seeding. However, conventional frame-based techniques require both high spatial and temporal resolution cameras,…

Computer Vision and Pattern Recognition · Computer Science 2024-03-05 Shintaro Shiba , Friedhelm Hamann , Yoshimitsu Aoki , Guillermo Gallego

Complex blur such as the mixup of space-variant and space-invariant blur, which is hard to model mathematically, widely exists in real images. In this paper, we propose a novel image deblurring method that does not need to estimate blur…

Computer Vision and Pattern Recognition · Computer Science 2020-11-17 Chunzhi Gu , Xuequan Lu , Ying He , Chao Zhang

Approximate Bayesian inference on the basis of summary statistics is well-suited to complex problems for which the likelihood is either mathematically or computationally intractable. However the methods that use rejection suffer from the…

Computation · Statistics 2010-05-04 M. G. B. Blum , O. Francois

We reconsider a nonparametric density model based on Gaussian processes. By augmenting the model with latent P\'olya--Gamma random variables and a latent marked Poisson process we obtain a new likelihood which is conjugate to the model's…

Machine Learning · Statistics 2018-05-30 Christian Donner , Manfred Opper

Constraints on cosmological parameters from large-scale structure have traditionally been obtained from two-point statistics. However, non-linear structure formation renders these statistics insufficient in capturing the full information…

Cosmology and Nongalactic Astrophysics · Physics 2017-11-22 Alex Hall , Alexander Mead

A range of nonlinear image reconstruction procedures based on extremizing the generalized Shannon entropy, Kullback-Leibler cross-entropy and Renyi information measures and proposed by the author in early papers is presented. The…

Astrophysics · Physics 2007-05-23 Anisa T. Bajkova

We develop Bayesian models for density regression with emphasis on discrete outcomes. The problem of density regression is approached by considering methods for multivariate density estimation of mixed scale variables, and obtaining…

Methodology · Statistics 2019-08-14 Georgios Papageorgiou

We present a new method for extracting the true 3-d velocity and density fields from the nonlinear redshift--space projected density field. The method is based on the nonlinear, nonlocal transformation of the density field. We assume a…

Astrophysics · Physics 2015-06-24 A. N. Taylor , M. Rowan-Robinson

Schlieren imaging is a powerful, non-intrusive method widely used to visualize refractive index gradients in fluid dynamics and heat transfer studies, essential in fields like aerospace engineering, combustion analysis, and supersonic flow…

Optics · Physics 2025-04-09 Shubham Saxena , Xu Wang

We explain how effective automatic probability density function estimates can be constructed using contemporary Bayesian inference engines such as those based on no-U-turn sampling and expectation propagation. Extensive simulation studies…

Machine Learning · Statistics 2021-09-28 M. P. Wand , J. C. F. Yu

In this paper, a new probability density function (pdf) is proposed to model the statistics of wavelet coefficients, and a simple Kalman's filter is derived from the new pdf using Bayesian estimation theory. Specifically, we decompose the…

Computer Vision and Pattern Recognition · Computer Science 2016-08-03 Mario Mastriani , Alberto E. Giraldez

It is now practically the norm for data to be very high dimensional in areas such as genetics, machine vision, image analysis and many others. When analyzing such data, parametric models are often too inflexible while nonparametric…

Methodology · Statistics 2011-05-31 Abhishek Bhattacharya , Garritt Page , David Dunson

Tomographic reconstruction, despite its revolutionary impact on a wide range of applications, suffers from its ill-posed nature in that there is no unique solution because of limited and noisy measurements. Therefore, in the absence of…

Applications · Statistics 2023-04-10 Agnimitra Dasgupta , Carlo Graziani , Zichao Wendy Di

Hyperspectral X-rays imaging holds promise for three-dimensional (3D) chemical analysis but remains limited in simultaneously capturing phase and absorption information due to complex setups and data burdens. We introduce quantitative X-ray…

Optics · Physics 2025-04-30 Herve Hugonne , KyeoReh Lee , Sugeun Jo , Jun Lim , YongKeun Park

In this work we present the first non-linear, non-Gaussian full Bayesian large scale structure analysis of the cosmic density field conducted so far. The density inference is based on the Sloan Digital Sky Survey data release 7, which…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 J. Jasche , F. S. Kitaura , C. Li , T. A. Ensslin

Thin films or sheets subjected to external forces often undergo mechanical instability, leading to regular patterns of wrinkles, folds, and creases. As can be anticipated from the difficulty of flattening a curved globe, any natural…

Pattern Formation and Solitons · Physics 2025-02-13 Megha Emerse , Lucas Goehring

This work presents a new procedure to extract features of grey-level texture images based on the discrete Schroedinger transform. This is a non-linear transform where the image is mapped as the initial probability distribution of a wave…

Computer Vision and Pattern Recognition · Computer Science 2016-12-09 João B. Florindo , Odemir M. Bruno

Using Kalman techniques, it is possible to perform optimal estimation in linear Gaussian state-space models. We address here the case where the noise probability density functions are of unknown functional form. A flexible Bayesian…

Statistics Theory · Mathematics 2009-11-13 François Caron , Manuel Davy , Arnaud Doucet , Emmanuel Duflos , Philippe Vanheeghe