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Related papers: Clustered Radio Interferometric Calibration

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We study a clustering problem where the goal is to maximize the coverage of the input points by $k$ chosen centers. Specifically, given a set of $n$ points $P \subseteq \mathbb{R}^d$, the goal is to pick $k$ centers $C \subseteq…

Computational Geometry · Computer Science 2020-04-14 Arturs Backurs , Sariel Har-Peled

Calibration of instrumental polarization is critical for measuring polarized radio emissions from astrophysical sources to extract the magnetic field information in astrophysical, heliospheric, and terrestrial plasmas. At meter wavelengths,…

Instrumentation and Methods for Astrophysics · Physics 2025-05-08 Devojyoti Kansabanik , Angelos Vourlidas , Soham Dey , Surajit Mondal , Divya Oberoi

Mode clustering is a nonparametric method for clustering that defines clusters using the basins of attraction of a density estimator's modes. We provide several enhancements to mode clustering: (i) a soft variant of cluster assignment, (ii)…

Methodology · Statistics 2015-12-23 Yen-Chi Chen , Christopher R. Genovese , Larry Wasserman

Many studies in data mining have proposed a new learning called semi-Supervised. Such type of learning combines unlabeled and labeled data which are hard to obtain. However, in unsupervised methods, the only unlabeled data are used. The…

Machine Learning · Computer Science 2013-04-16 Badreddine Meftahi , Ourida Ben Boubaker Saidi

In this paper, we aim to design robust estimation techniques based on the compound-Gaussian (CG) process and adapted for calibration of radio interferometers. The motivation beyond this is due to the presence of outliers leading to an…

Applications · Statistics 2018-07-31 Virginie Ollier , Mohammed Nabil El Korso , André Ferrari , Rémy Boyer , Pascal Larzabal

We present a catalog of 321 compact radio sources in the declination range 0deg > delta > -30deg. The positions of these sources have been measured with a two-dimensional rms accuracy of 35 milliarcseconds using the NRAO Very Large Array.…

Astrophysics · Physics 2009-11-07 Joshua N. Winn , Alok R. Patnaik , J. M. Wrobel

We aim to evaluate the possibility of improving the ICRS realization starting from the ICRF2 catalogue by investigating the coordinate time series of radio sources observed by VLBI between 1979 and 2016. Sources with long observational…

Astrophysics of Galaxies · Physics 2017-02-14 N. Liu , J. -C. Liu , Z. Zhu

There has been much interest recently in developing fair clustering algorithms that seek to do justice to the representation of groups defined along sensitive attributes such as race and gender. We observe that clustering algorithms could…

Machine Learning · Computer Science 2023-01-02 Stanley Simoes , Deepak P , Muiris MacCarthaigh

The problem of clustering noisy and incompletely observed high-dimensional data points into a union of low-dimensional subspaces and a set of outliers is considered. The number of subspaces, their dimensions, and their orientations are…

Machine Learning · Statistics 2015-08-24 Reinhard Heckel , Helmut Bölcskei

Clustering is an unsupervised machine learning methodology where unlabeled elements/objects are grouped together aiming to the construction of well-established clusters that their elements are classified according to their similarity. The…

Machine Learning · Statistics 2023-10-20 Dimitrios Saligkaras , Vasileios E. Papageorgiou

We consider a multiterminal source coding problem in which a source is estimated at a central processing unit from lossy-compressed remote observations. Each lossy-encoded observation is produced by a remote sensor which obtains a noisy…

Information Theory · Computer Science 2016-05-13 Ruiyang Song , Stefano Rini , Alon Kipnis , Andrea J. Goldsmith

The area of constrained clustering has been extensively explored by researchers and used by practitioners. Constrained clustering formulations exist for popular algorithms such as k-means, mixture models, and spectral clustering but have…

Machine Learning · Computer Science 2021-01-11 Hongjing Zhang , Tianyang Zhan , Sugato Basu , Ian Davidson

Interference coordination improves data rates and reduces outages in cellular networks. Accurately evaluating the gains of coordination, however, is contingent upon using a network topology that models realistic cellular deployments. In…

Information Theory · Computer Science 2015-06-11 Salam Akoum , Robert W. Heath

The calibration of sensors comprising inertial measurement units is crucial for reliable and accurate navigation. Such calibration is usually performed with specialized expensive rotary tables or requires sophisticated signal processing…

Signal Processing · Electrical Eng. & Systems 2024-06-04 Marek W. Rupniewski

Superclusters and galaxy clusters offer a wide range of astrophysical science topics with regards to studying the evolution and distribution of galaxies, intra-cluster magnetization mediums, cosmic ray accelerations and large scale diffuse…

Instrumentation and Methods for Astrophysics · Physics 2021-11-04 V. Parekh , R. Kincaid , B. Hugo , A. Ramaila , N. Oozeer

An important form of prior information in clustering comes in form of cannot-link and must-link constraints. We present a generalization of the popular spectral clustering technique which integrates such constraints. Motivated by the…

Machine Learning · Statistics 2015-05-26 Syama Sundar Rangapuram , Matthias Hein

The relationship between the clustering of dark matter and that of luminous matter is often described using the bias parameter. Here, we provide a new method to probe the bias of intermediate to high-redshift radio continuum sources for…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Sean Passmoor , Catherine Cress , Andreas Faltenbacher , Russell Johnston , Mathew Smith , Ando Ratsimbazafy , Ben Hoyle

We discuss a method aiming to use photometric redshifts in lensing clusters to access the population of distant background sources. The amplification provided by gravitational lensing allows to calibrate photometric redshifts 1 to 3…

Astrophysics · Physics 2007-05-23 Roser Pello , Jean-Paul Kneib , Micol Bolzonella , Joan-Marc Miralles

Calibration of a sensor array is more involved if the antennas have direction dependent gains and multiple calibrator sources are simultaneously present. We study this case for a sensor array with arbitrary geometry but identical elements,…

Instrumentation and Methods for Astrophysics · Physics 2010-03-10 Stefan J. Wijnholds , Alle-Jan van der Veen

Image clustering is a very useful technique that is widely applied to various areas, including remote sensing. Recently, visual representations by self-supervised learning have greatly improved the performance of image clustering. To…

Computer Vision and Pattern Recognition · Computer Science 2022-09-27 Qinglin Li , Guoping Qiu
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