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We update the search for features, due to transient reductions in inflaton's speed of sound, in the Cosmic Microwave Background (CMB) angular power spectrum using Planck 2018 temperature, polarization and lensing data. We develop a new…

Cosmology and Nongalactic Astrophysics · Physics 2021-06-23 Guadalupe Cañas-Herrera , Jesús Torrado , Ana Achúcarro

Consider a set of n images of a scene with dynamic objects captured with a static or a handheld camera. Let the temporal order in which these images are captured be unknown. There can be n! possibilities for the temporal order in which…

Computer Vision and Pattern Recognition · Computer Science 2020-10-23 Gagan Kanojia , Shanmuganathan Raman

We have presented a new and alternative algorithm for noise reduction using the methods of discrete wavelet transform and numerical differentiation of the data. In our method the threshold for reducing noise comes out automatically. The…

Sparse representation systems that encode signal architecture have had a profound impact on sampling and compression paradigms. Remarkable examples are multi-scale directional systems, which, similar to our vision system, encode the…

Fluid Dynamics · Physics 2026-02-05 Elias Zea , Marco Laudato , Joakim Andén

This method solves the dual problem of blind deconvolution and estimation of the time waveform of noisy second-order cyclo-stationary (CS2) signals that traverse a Transfer Function (TF) en route to a sensor. We have proven that the…

Machine Learning · Computer Science 2024-03-07 Igor Makienko , Michael Grebshtein , Eli Gildish

We present predictions on the angular power spectrum of CMB fluctuations due to extragalactic point sources (EPS) by using a method for simulating realistic 2D distributions of clustered EPS. Both radio and far--IR selected source…

Astrophysics · Physics 2009-11-10 J. González-Nuevo , L. Toffolatti , F. Argüeso

The largest uncollapsed inhomogeneity in the observable Universe is statistically represented in the quadrupole signal of the cosmic microwave background (CMB) sky maps as observed by the Wilkinson Microwave Anisotropy Probe (WMAP). The…

Cosmology and Nongalactic Astrophysics · Physics 2010-08-09 Boudewijn F. Roukema

This paper provides central limit theorems for the wavelet packet decomposition of stationary band-limited random processes. The asymptotic analysis is performed for the sequences of the wavelet packet coefficients returned at the nodes of…

Information Theory · Computer Science 2009-10-26 Abdourrahmane Atto , Dominique Pastor

In exploration seismology, seismic inversion refers to the process of inferring physical properties of the subsurface from seismic data. Knowledge of physical properties can prove helpful in identifying key structures in the subsurface for…

Signal Processing · Electrical Eng. & Systems 2019-06-07 Ahmad Mustafa , Motaz Alfarraj , Ghassan AlRegib

Though widely used in image classification, convolutional neural networks (CNNs) are prone to noise interruptions, i.e. the CNN output can be drastically changed by small image noise. To improve the noise robustness, we try to integrate…

Computer Vision and Pattern Recognition · Computer Science 2021-09-01 Qiufu Li , Linlin Shen , Sheng Guo , Zhihui Lai

The identification of non-Gaussian signatures in cosmic microwave background (CMB) temperature maps is one of the main cosmological challenges today. We propose and investigate altenative methods to analyse CMB maps. Using the technique of…

Astrophysics · Physics 2009-11-07 C. Raeth , P. Schuecker

We study the possibility for constraining the topology of the Universe by means of the matched circles statistic applied to polarised cosmic microwave background (CMB) anisotropy maps. The advantages of using the CMB polarisation maps in…

Cosmology and Nongalactic Astrophysics · Physics 2018-02-09 P. Bielewicz , A. J. Banday , K. M. Gorski

Our objective is to discover and localize monotonic temporal changes in a sequence of images. To achieve this, we exploit a simple proxy task of ordering a shuffled image sequence, with `time' serving as a supervisory signal, since only…

Computer Vision and Pattern Recognition · Computer Science 2024-08-14 Charig Yang , Weidi Xie , Andrew Zisserman

We use wavelet and curvelet transforms to extract signals of cosmic strings from cosmic microwave background (CMB) temperature anisotropy maps, and to study the limits on the cosmic string tension which various ongoing CMB temperature…

Cosmology and Nongalactic Astrophysics · Physics 2017-06-21 Lukas Hergt , Adam Amara , Robert Brandenberger , Tomasz Kacprzak , Alexandre Refregier

Key graph-based problems play a central role in understanding network topology and uncovering patterns of similarity in homogeneous and temporal data. Such patterns can be revealed by analyzing communities formed by nodes, which in turn can…

Distributed, Parallel, and Cluster Computing · Computer Science 2025-10-02 Davide Rucci , Emanuele Carlini , Patrizio Dazzi , Hanna Kavalionak , Matteo Mordacchini

E to B mixing or "leakage" due to time-ordered data (TOD) filtering has become an important source of sensitivity loss that ground-based cosmic microwave background polarization experiments must address. However, it is a difficult problem…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-20 Yuyang Zhou , Adrian Lee , Yuji Chinone

In the context of Cosmic Microwave Background data analysis, we study the solution to the equation that transforms scanning data into a map. As originally suggested in "messenger" methods for solving linear systems, we split the noise…

Cosmology and Nongalactic Astrophysics · Physics 2021-12-08 Bai-Chiang Chiang , Kevin M. Huffenberger

The statistical characterization of the diffuse magnetized ISM and Galactic foregrounds to the CMB poses a major challenge. To account for their non-Gaussian statistics, we need a data analysis approach capable of efficiently quantifying…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-28 Bruno Regaldo-Saint Blancard , François Levrier , Erwan Allys , Elena Bellomi , François Boulanger

One of the hallmarks of active galactic nuclei are that they are highly variable with time. In watching the spectra vary it has been observed that the emission-lines often appear to "reverberate" -- that is they vary in response to…

Astrophysics of Galaxies · Physics 2026-05-28 Kirk Long , Keith Horne , Jason Dexter , Benoit Tremblay

In this contribution, we consider the problem of blind source separation in a Bayesian estimation framework. The wavelet representation allows us to assign an adequate prior distribution to the wavelet coefficients of the sources. MCMC…

Data Analysis, Statistics and Probability · Physics 2009-11-10 Mahieddine M. Ichir , Ali Mohammad-Djafari