English
Related papers

Related papers: Constraint matrix factorization for space variant …

200 papers

Unsupervised feature selection (UFS) is widely applied in machine learning and pattern recognition. However, most of the existing methods only consider a single sparsity, which makes it difficult to select valuable and discriminative…

Optimization and Control · Mathematics 2025-01-03 Xianchao Xiu , Anning Yang , Chenyi Huang , Xinrong Li , Wanquan Liu

Images from adaptive optics systems are generally affected by significant distortions of the point spread function (PSF) across the field of view, depending on the position of natural and artificial guide stars. Image reduction techniques…

Instrumentation and Methods for Astrophysics · Physics 2015-06-24 Andrea La Camera , Laura Schreiber , Emiliano Diolaiti , Patrizia Boccacci , Mario Bertero , Michele Bellazzini , Paolo Ciliegi

The Point Spread Function (PSF) is a key figure of merit for specifying the angular resolution of optical systems and, as the demand for higher and higher angular resolution increases, the problem of surface finishing must be taken…

Instrumentation and Methods for Astrophysics · Physics 2016-10-04 K. Tayabaly , D. Spiga , G. Sironi , R. Canestrari , M. Lavagna , G. Pareschi

We propose a new method for Point Spread Function (PSF) correction in weak gravitational lensing shear analysis using an artificial image with the same ellipticity as the lensed image. This avoids the systematic error associated with the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-19 Yuki Okura , Toshifumi Futamase

A simple theoretical framework for the description and interpretation of spatially correlated modelling residuals is presented, and the resulting tools are found to provide a useful aid to model selection in the context of weak…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-11 Barnaby Rowe

We have developed a novel method for co-adding multiple under-sampled images that combines the iteratively reweighted least squares and divide-and-conquer algorithms. Our approach not only allows for the anti-aliasing of the images but also…

Instrumentation and Methods for Astrophysics · Physics 2024-02-29 Lei Wang , Huanyuan Shan , Lin Nie , Dezi Liu , Zhaojun Yan , Guoliang Li , Cheng Cheng , Yushan Xie , Han Qu , Wenwen Zheng , Xi Kang

Spatial frequency estimation from a mixture of noisy sinusoids finds applications in various fields. While subspace-based methods offer cost-effective super-resolution parameter estimation, they demand precise array calibration, posing…

Signal Processing · Electrical Eng. & Systems 2024-10-23 Tianyi Liu , Sai Pavan Deram , Khaled Ardah , Martin Haardt , Marc E. Pfetsch , Marius Pesavento

We have shown that the vector of the point spread function (PSF) lexicographical presentation belongs to the left side conjugated null space (NS) of the autoregression (AR) matrix operator on condition the AR parameters are common for…

Computer Vision and Pattern Recognition · Computer Science 2015-03-02 Yuriy A. Bunyak , Roman N. Kvetnyy , Olga Yu. Sofina

The point-spread function (PSF) of an adaptive optics (AO) system is often poorly known. This ignorance can lead to significant systematic errors in photometry. Since the degree of AO correction is sensitive to the observing conditions:…

Astrophysics · Physics 2010-11-11 Christopher D. Sheehy , Nate McCrady , James R. Graham

Robust Principal Component Analysis (RPCA) is a fundamental technique for decomposing data into low-rank and sparse components, which plays a critical role for applications such as image processing and anomaly detection. Traditional RPCA…

Machine Learning · Computer Science 2024-12-20 Kexin Li , You-wei Wen , Xu Xiao , Mingchao Zhao

The control of systematic effects when measuring galaxy shapes is one of the main challenges for cosmic shear analyses. In this context, we study the fundamental limitations on shear accuracy due to the measurement of the Point Spread…

Astrophysics · Physics 2009-11-13 S. Paulin-Henriksson , A. Amara , L. Voigt , A. Refregier , S. L. Bridle

The convolution of galaxy images by the point-spread function (PSF) is the dominant source of bias for weak gravitational lensing studies, and an accurate estimate of the PSF is required to obtain unbiased shape measurements. The PSF…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-16 Martin Eriksen , Henk Hoekstra

Pansharpening techniques aim at fusing low-resolution multispectral (MS) images and high-resolution panchromatic (PAN) images to produce high-resolution MS images. Despite significant progress in the field, spectral and spatial distortions…

Computer Vision and Pattern Recognition · Computer Science 2019-03-15 Joan Duran , Antoni Buades

This paper proposes a novel spatiotemporal (ST) fusion framework for satellite images, named Robust Optimization-based Spatiotemporal Fusion (ROSTF). ST fusion is a promising approach to resolve a trade-off between the temporal and spatial…

Image and Video Processing · Electrical Eng. & Systems 2024-07-01 Ryosuke Isono , Kazuki Naganuma , Shunsuke Ono

The ill-posed problem of phase retrieval in optics, using one or more intensity measurements, has a multitude of applications using electromagnetic or matter waves. Many phase retrieval algorithms are computed on pixel arrays using discrete…

Image and Video Processing · Electrical Eng. & Systems 2022-09-21 J. A. Pollock , K. S. Morgan , L. C. P. Croton , M. K. Croughan , G. Ruben , N. Yagi , H. Sekiguchi , M. J. Kitchen

Factor analysis (FA) or principal component analysis (PCA) models the covariance matrix of the observed data as R = SS' + {\Sigma}, where SS' is the low-rank covariance matrix of the factors (aka latent variables) and {\Sigma} is the…

Methodology · Statistics 2023-05-31 Petre Stoica , Prabhu Babu

Modern Giant Segmented Mirror Telescopes (GSMTs) like the Extremely Large Telescope, which is currently under construction, depend heavily on Adaptive Optics (AO) systems to correct for atmospheric distortions. However, a residual blur…

Instrumentation and Methods for Astrophysics · Physics 2023-07-05 Roland Wagner , Jenny Niebsch , Ronny Ramlau

We introduce the probabilistic sequential matrix factorization (PSMF) method for factorizing time-varying and non-stationary datasets consisting of high-dimensional time-series. In particular, we consider nonlinear Gaussian state-space…

Machine Learning · Statistics 2021-03-19 Ömer Deniz Akyildiz , Gerrit J. J. van den Burg , Theodoros Damoulas , Mark F. J. Steel

We examined the anisotropic point spread function (PSF) of Suprime-Cam data utilizing dense star field data. We decomposed the PSF ellipticities into three components, the optical aberration, atmospheric turbulence, and chip-misalignment in…

Instrumentation and Methods for Astrophysics · Physics 2015-06-15 Takashi Hamana , Satoshi Miyazaki , Yuki Okura , Tomohiro Okamura , Toshifumi Futamase

In the field of data mining, how to deal with high-dimensional data is an inevitable problem. Unsupervised feature selection has attracted more and more attention because it does not rely on labels. The performance of spectral-based…

Machine Learning · Computer Science 2021-01-01 Zhengxin Li , Feiping Nie , Jintang Bian , Xuelong Li
‹ Prev 1 3 4 5 6 7 10 Next ›