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CBCT images suffer from acute shading artifacts primarily due to scatter. Numerous image-domain correction algorithms have been proposed in the literature that use patient-specific planning CT images to estimate shading contributions in…

Computer Vision and Pattern Recognition · Computer Science 2018-01-18 Awais Ashfaq , Jonas Adler

We introduce the Bayesian Global Sky Model (B-GSM), a novel data-driven Bayesian approach to modelling radio foregrounds at frequencies <400~MHz. B-GSM aims to address the limitations of previous models by incorporating robust error…

Instrumentation and Methods for Astrophysics · Physics 2025-11-12 George Carter , Will Handley , Mark Ashdown , Nima Razavi-Ghods

A method is developed for fitting theoretically predicted astronomical spectra to an observed spectrum. Using a hierarchical Bayesian principle, the method takes both systematic and statistical measurement errors into account, which has not…

Astrophysics · Physics 2008-11-26 Z. Shkedy , L. Decin , G. Molenberghs , C. Aerts

Spectroscopy requires high-precision wavelength discrimination but typically requires bulky, alignment-sensitive instrumentation. To address this, we present a compact computational spectrometer built from a single germanium PN photodiode.…

We present a Bayesian framework to establish a power-spectrum space decomposition of frequency tomographic (PSDFT) data for future intensity mapping (IM) experiments. Different from most traditional component-separation methods which work…

Instrumentation and Methods for Astrophysics · Physics 2023-08-30 Chang Feng , Filipe B. Abdalla

Bayesian causal inference offers a principled approach to policy evaluation of proposed interventions on mediators or time-varying exposures. We outline a general approach to the estimation of causal quantities for settings with…

Methodology · Statistics 2019-02-28 Leah Comment , Brent A. Coull , Corwin Zigler , Linda Valeri

The precise measurement of the sky-averaged HI absorption signal between 50 and 200 MHz is the primary goal of global 21-cm cosmology. This measurement has the potential to unravel the underlying physics of cosmic structure formation and…

Cosmology and Nongalactic Astrophysics · Physics 2024-12-04 Emma Shen , Dominic Anstey , Marta Spinelli , Eloy de Lera Acedo , Anastasia Fialkov

Scatter signals can degrade the contrast and resolution of computed tomography (CT) images and induce artifacts. How to effectively correct scatter signals in CT has always been a focal point of research for researchers. This work presents…

Medical Physics · Physics 2025-01-10 Guiyuan Lin , Shiwo Deng , Xiaoqun Wang , Xing Zhao

Broadband receiver data need colour corrections applying to correct for the different source spectra across their wide bandwidths. The full integration over a receiver bandpass may be computationally expensive and redundant when repeated…

Bayesian parametric analytic continuation (BPAC) is proposed for the analytic continuation of noisy imaginary-time Green's function data as, e.g., obtained by continuous-time quantum Monte Carlo simulations (CTQMC). Within BPAC, the…

Strongly Correlated Electrons · Physics 2019-08-27 Michael Rumetshofer , Daniel Bauernfeind , Wolfgang von der Linden

One approach to extracting the global 21-cm signal from total-power measurements at low radio frequencies is to parametrize the different contributions to the data and then fit for these parameters. We examine parametrizations of the 21-cm…

Cosmology and Nongalactic Astrophysics · Physics 2015-12-04 Geraint J. A. Harker , Jordan Mirocha , Jack O. Burns , Jonathan R. Pritchard

We present a data-driven method - heteroscedastic matrix factorization, a kind of probabilistic factor analysis - for modeling or performing dimensionality reduction on observed spectra or other high-dimensional data with known but…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 P. Tsalmantza , David W. Hogg

Cone-beam CT (CBCT) is installed in the treatment room to facilitate online clinical applications, including image guidance in radiation and surgery. Half-fan and short-can are the commonly used modes in clinical applications to expand the…

Medical Physics · Physics 2022-05-24 Junbo Peng

I describe an approach to fitting and comparison of radio spectra based on Bayesian analysis and realised using a new implementation of the nested sampling algorithm. Such an approach improves on the commonly used maximum-likelihood fitting…

Instrumentation and Methods for Astrophysics · Physics 2009-12-14 Bojan Nikolic

Fine-grained visual categorization (FGVC), which aims at classifying objects with small inter-class variances, has been significantly advanced in recent years. However, ultra-fine-grained visual categorization (ultra-FGVC), which targets at…

Computer Vision and Pattern Recognition · Computer Science 2021-10-28 Yajie Sun , Miaohua Zhang , Xiaohan Yu , Yi Liao , Yongsheng Gao

Edge-coloured directed graphs provide an essential structure for modelling and analysis of complex systems arising in many scientific disciplines (e.g. feature-oriented systems, gene regulatory networks, etc.). One of the fundamental…

Data Structures and Algorithms · Computer Science 2023-06-22 Nikola Beneš , Luboš Brim , Samuel Pastva , David Šafránek

Analyses of the cosmic 21-cm signal are hampered by astrophysical foregrounds that are far stronger than the signal itself. These foregrounds, typically confined to a wedge-shaped region in Fourier space, often necessitate the removal of a…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-02 Nashwan Sabti , Ram Reddy , Julian B. Muñoz , Siddharth Mishra-Sharma , Taewook Youn

We present the Bayesian Global Sky Model (B-GSM), a new absolutely calibrated model of the diffuse Galactic foreground at frequencies below 408 MHz. We assemble a dataset of publicly available diffuse emission maps at frequencies between 45…

Instrumentation and Methods for Astrophysics · Physics 2025-04-08 George Carter , Will Handley , Mark Ashdown , Nima Razavi-Ghods

We apply two Bayesian hierarchical inference schemes to infer shear power spectra, shear maps and cosmological parameters from the CFHTLenS weak lensing survey - the first application of this method to data. In the first approach, we sample…

Cosmology and Nongalactic Astrophysics · Physics 2017-05-10 Justin Alsing , Alan F. Heavens , Andrew H. Jaffe

The characterization of a binary function by partial frequency information is considered. We show that it is possible to reconstruct binary signals from incomplete frequency measurements via the solution of a simple linear optimization…

Information Theory · Computer Science 2012-04-19 Yu Mao