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Probabilistic principal component analysis (PPCA) seeks a low dimensional representation of a data set in the presence of independent spherical Gaussian noise, Sigma = (sigma^2)*I. The maximum likelihood solution for the model is an…

Machine Learning · Statistics 2011-06-23 Alfredo A. Kalaitzis , Neil D. Lawrence

The ability to accurately measure the shapes of faint objects in images taken with the Advanced Camera for Surveys(ACS) on the Hubble Space Telescope (HST) depends upon detailed knowledge of the Point Spread Function (PSF). We show that…

We consider the problem of robustly recovering a $k$-sparse coefficient vector from the Fourier series that it generates, restricted to the interval $[- \Omega, \Omega]$. The difficulty of this problem is linked to the superresolution…

Information Theory · Computer Science 2015-02-06 Laurent Demanet , Nam Nguyen

Investigations of the point spread functions (PSFs) and flux calibrations for stacking analysis have been performed with the far-infrared (wavelengths range of 60 to 140 um all-sky maps taken by the Far-Infrared Surveyor (FIS) onboard the…

Instrumentation and Methods for Astrophysics · Physics 2015-06-19 Ko Arimatsu , Yasuo Doi , Takehiko Wada , Satoshi Takita , Mitsunobu Kawada , Shuji Matsuura , Takafumi Ootsubo , Hirokazu Kataza

In positron emission tomography (PET) imaging, statistical iterative reconstruction (IR) techniques appear particularly promising since they can provide accurate system model. The system model matrix which describes the relationship between…

Faint red galaxies in the Sloan Digital Sky Survey show a puzzling clustering pattern in previous measurements. In the two-point correlation function (2PCF), they appear to be strongly clustered on small-scales, indicating a tendency to…

Astrophysics of Galaxies · Physics 2016-06-06 Haojie Xu , Zheng Zheng , Hong Guo , Ju Zhu , Idit Zehavi

Thermal infrared (TIR) target tracking methods often adopt the correlation filter (CF) framework due to its computational efficiency. However, the low resolution of TIR images, along with tracking interference, significantly limits the…

Computer Vision and Pattern Recognition · Computer Science 2025-04-22 Shang Zhang , Xiaobo Ding , Huanbin Zhang , Ruoyan Xiong , Yue Zhang

Interferometers (e.g. ALMA and NOEMA) allow us to obtain the detailed brightness distribution of astronomical sources in 3 dimensions (R.A., Dec., frequency). However, the spatial correlation of the noise makes it difficult to evaluate the…

Instrumentation and Methods for Astrophysics · Physics 2023-02-21 Takafumi Tsukui , Satoru Iguchi , Ikki Mitsuhashi , Kenichi Tadaki

One way of imaging X-ray emission from solar flares is to measure Fourier components of the spatial X-ray source distribution. We present a new Compressed Sensing-based algorithm named VIS_CS, which reconstructs the spatial distribution…

Solar and Stellar Astrophysics · Physics 2017-11-01 Simon Felix , Roman Bolzern , Marina Battaglia

The desire for wide-field of view, large fractional bandwidth, high sensitivity, high spectral and temporal resolution has driven radio interferometry to the point of big data revolution where the data is represented in at least three…

Instrumentation and Methods for Astrophysics · Physics 2020-09-30 M. Atemkeng , O. Smirnov , C. Tasse , G. Foster , S. Makhathini

Principal Component Analysis (PCA) is a dimension reduction technique. It produces inconsistent estimators when the dimensionality is moderate to high, which is often the problem in modern large-scale applications where algorithm…

Computation · Statistics 2016-01-29 Qiaoya Zhang , Yiyuan She

In many atmospheric and earth sciences, it is of interest to identify dominant spatial patterns of variation based on data observed at $p$ locations and $n$ time points with the possibility that $p>n$. While principal component analysis…

Methodology · Statistics 2016-02-29 Wen-Ting Wang , Hsin-Cheng Huang

Synthetic aperture sonar (SAS) image resolution is constrained by waveform bandwidth and array geometry. Specifically, the waveform bandwidth determines a point spread function (PSF) that blurs the locations of point scatterers in the…

Computer Vision and Pattern Recognition · Computer Science 2021-12-17 Albert Reed , Thomas Blanford , Daniel C. Brown , Suren Jayasuriya

This paper describes a fast and accurate method for obtaining steerable principal components from a large dataset of images, assuming the images are well localized in space and frequency. The obtained steerable principal components are…

Computer Vision and Pattern Recognition · Computer Science 2018-08-10 Boris Landa , Yoel Shkolnisky

An undersampled point spread function may interact with the microstructure of a solid-state detector such that the total flux detected can depend sensitively on where the PSF center falls within a pixel. Such intra-pixel sensitivity…

Astrophysics · Physics 2009-10-31 Tod R. Lauer

Slow feature analysis (SFA) is a method for extracting slowly varying features from a quickly varying multidimensional signal. An open source Matlab-implementation sfa-tk makes SFA easily useable. We show here that under certain…

Machine Learning · Statistics 2009-12-08 Wolfgang Konen

We propose to measure the weak cosmic shear using the spatial derivatives of the galaxy surface brightness field. The measurement should be carried out in Fourier space, in which the point spread function (PSF) can be transformed to a…

Astrophysics · Physics 2009-11-11 Jun Zhang

A compressive sensing (CS) reconstruction method for polynomial phase signals is proposed in this paper. It relies on the Polynomial Fourier transform, which is used to establish a relationship between the observation and sparsity domain.…

Information Theory · Computer Science 2016-11-15 Srdjan Stankovic , Irena Orovic , Ljubisa Stankovic

Faraday tomography offers crucial information on the magnetized astronomical objects, such as quasars, galaxies, or galaxy clusters, by observing its magnetoionic media. The observed linear polarization spectrum is inverse Fourier…

Instrumentation and Methods for Astrophysics · Physics 2020-11-24 Suchetha Cooray , Tsutomu T. Takeuchi , Takuya Akahori , Yoshimitsu Miyashita , Shinsuke Ideguchi , Keitaro Takahashi , Kiyotomo Ichiki

This paper presents a new Bayesian collaborative sparse regression method for linear unmixing of hyperspectral images. Our contribution is twofold; first, we propose a new Bayesian model for structured sparse regression in which the…

Computation · Statistics 2023-07-19 Yoann Altmann , Marcelo Pereyra , Jose Bioucas-Dias
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