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Related papers: Exploring the Spectral Space of Low Redshift QSOs

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We explore the utility of Karhunen Loeve (KL) analysis in solving practical problems in the analysis of gravitational shear surveys. Shear catalogs from large-field weak lensing surveys will be subject to many systematic limitations,…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Jake Vanderplas , Andrew Connolly , Bhuvnesh Jain , Mike Jarvis

Precision measurements of the galaxy power spectrum P(k) require a data analysis pipeline that is both fast enough to be computationally feasible and accurate enough to take full advantage of high-quality data. We present a rigorous…

Astrophysics · Physics 2009-10-07 Max Tegmark , Andrew Hamilton , Michael Strauss , Michael Vogeley , Alexander Szalay

The Karhunen-Lo\`eve transform (KLT) stands as a well-established discrete transform, demonstrating optimal characteristics in data decorrelation and dimensionality reduction. Its ability to condense energy compression into a select few…

Signal Processing · Electrical Eng. & Systems 2024-10-15 A. P. Radünz , D. F. G. Coelho , F. M. Bayer , R. J. Cintra , A. Madanayake

The Karhunen-Lo\`eve transform (KLT) is often used for data decorrelation and dimensionality reduction. The KLT is able to optimally retain the signal energy in only few transform components, being mathematically suitable for image and…

Image and Video Processing · Electrical Eng. & Systems 2024-10-15 A. P. Radünz , T. L. T. da Silveira , F. M. Bayer , R. J. Cintra

We perform an objective classification of 170,000 galaxy spectra in the Sloan Digital Sky Survey (SDSS) using the Karhunen-Lo\`eve (KL) transform. With about one-sixth of the total set of galaxy spectra which will be obtained by the survey,…

3D data compression techniques can be used to determine the natural basis of radial eigenmodes that encode the maximum amount of information in a tomographic large-scale structure survey. We explore the potential of the Karhunen-Lo\`eve…

Cosmology and Nongalactic Astrophysics · Physics 2019-12-16 Emilio Bellini , David Alonso , Shahab Joudaki , Ludovic van Waerbeke

The Karhunen-Lo\`eve transform (KLT) is often used for data decorrelation and dimensionality reduction. Because its computation depends on the matrix of covariances of the input signal, the use of the KLT in real-time applications is…

Image and Video Processing · Electrical Eng. & Systems 2021-11-30 A. P. Radünz , F. M. Bayer , R. J. Cintra

We obtain a sample of 87 radio-loud QSOs in the redshift range 3.6<z<4.4 by cross-correlating sources in the FIRST radio survey S{1.4GHz} > 1 mJy with star-like objects having r <20.2 in SDSS Data Release 7. Of these 87 QSOs, 80 are…

Astrophysics of Galaxies · Physics 2015-06-23 D. Tuccillo , J. I. Gonzalez-Serrano , C. R. Benn

Particle picking is currently a critical step in the cryo-EM single particle reconstruction pipeline. Despite extensive work on this problem, for many data sets it is still challenging, especially for low SNR micrographs. We present the KLT…

Data Analysis, Statistics and Probability · Physics 2019-12-16 Amitay Eldar , Boris Landa , Yoel Shkolnisky

The Largest Cluster Statistics\,(LCS) analysis of the redshifted 21\,cm maps has been demonstrated to be an efficient and robust method for following the time evolution of the largest ionized regions\,(LIRs) during the Epoch of…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-28 Samit Kumar Pal , Saswata Dasgupta , Abhirup Datta , Suman Majumdar , Satadru Bag , Prakash Sarkar

This paper introduces a technique called NKL, which cleans both polarized and unpolarized foregrounds from HI intensity maps by applying a Karhunen-Lo\`eve transform on the needlet coefficients. In NKL, one takes advantage of correlations…

Cosmology and Nongalactic Astrophysics · Physics 2023-11-03 John Podczerwinski , Peter Timbie

The Karhunen-Lo\'{e}ve (KL) eigenvectors and eigenvalues of the sample correlation matrix are used to analyse the spatial fluctuations of the REFLEX clusters of galaxies. The method avoids the disturbing effects of correlated power spectral…

Astrophysics · Physics 2011-07-19 Peter Schuecker , Luigi Guzzo , Chris A. Collins , Hans Boehringer

Signals obtained in land seismic surveys are usually contaminated with coherent noise, among which the ground roll (Rayleigh surface waves) is of major concern for it can severely degrade the quality of the information obtained from the…

Pattern Formation and Solitons · Physics 2009-11-11 Raul Montagne , Giovani L. Vasconcelos

We show that the first 10 eigencomponents of the Karhunen-Lo\`eve expansion or Principal Component Analysis (PCA) provide a robust classification scheme for the identification of stars, galaxies and quasi-stellar objects from multi-band…

Astrophysics · Physics 2009-11-07 Remi A. Cabanac , Valerie de Lapparent , Paul Hickson

Being motivated by the multilayer RECOS (REctified-COrrelations on a Sphere) transform, we develop a data-driven Saak (Subspace approximation with augmented kernels) transform in this work. The Saak transform consists of three steps: 1)…

Computer Vision and Pattern Recognition · Computer Science 2017-10-17 C. -C. Jay Kuo , Yueru Chen

The scientific value of the next generation of large continuum surveys would be greatly increased if the redshifts of the newly detected sources could be rapidly and reliably estimated. Given the observational expense of obtaining…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-03 S. J. Curran , J. P. Moss , Y. C. Perrott

Application of Karhunen-Loeve decomposition (KLD, or singular value decomposition) is presented for analysis of the spatio-temporal dynamics of wide-aperture vertical cavity surface emitting laser (VCSEL), considered as a thin-layer system.…

Optics · Physics 2007-05-23 M. U. Karelin , P. V. Paulau , I. V. Babushkin

In the near future, new surveys promise a significant increase in the number of quasars (QSO) at large redshifts. This will help to constrain the dark energy models using quasars. The Large Synoptic Survey Telescope (LSST) will cover over…

Astrophysics of Galaxies · Physics 2019-10-08 Mary Loli Martínez-Aldama , Swayamtrupta Panda , Bożena Czerny , Michal Zajaček

Fluid antenna systems (FAS) achieve spatial diversity by dynamically switching among $N$ densely packed ports, but the resulting spatially correlated Rayleigh channels render exact outage analysis intractable. Existing block-correlation…

Signal Processing · Electrical Eng. & Systems 2026-03-24 Tuo Wu

The discovery of outsiders in the form of unusual, rare, or even unknown object types is important as they can provide useful information about otherwise hidden physical phenomena and processes. The present study takes advantage of the fact…

Astrophysics of Galaxies · Physics 2026-01-14 Helmut Meusinger
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