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We describe a method for spectral cleaning and timing calibration of short voltage time series data from individual radio interferometer receivers. It makes use of the phase differences in Fast Fourier Transform (FFT) spectra across antenna…

Instrumentation and Methods for Astrophysics · Physics 2016-05-04 A. Corstanje , S. Buitink , J. E. Enriquez , H. Falcke , J. R. Hörandel , M. Krause , A. Nelles , J. P. Rachen , P. Schellart , O. Scholten , S. ter Veen , S. Thoudam , T. N. G. Trinh

Interference alignment (IA) is known to significantly increase sum-throughput at high SNR in the presence of multiple interfering nodes, however, the reliability of IA is little known, which is the subject of this paper. We study the error…

Information Theory · Computer Science 2012-11-28 Baile Xie , Yang Li , Hlaing Minn , Aria Nosratinia

The matrix element technique provides a superior statistical sensitivity for precision measurements of important parameters at hadron colliders, such as the mass of the top quark or the cross section for the production of Higgs bosons. The…

High Energy Physics - Experiment · Physics 2014-11-20 Oleg Brandt , Gaston Gutierrez , Michael H. L. S. Wang , Zhenyu Ye

We report on a broader evaluation of statistical bootstrap resampling methods as a tool for pixel-level calibration and imaging fidelity assessment in radio interferometry. Pixel-level imaging fidelity assessment is a challenging problem,…

Instrumentation and Methods for Astrophysics · Physics 2015-05-14 Athol Kemball , Adam Martinsek , Modhurita Mitra , Hsin-Fang Chiang

This paper studies the convergence difficulty of cohesive zone models in static analysis. It is shown that an inappropriate starting point of iterations in the Newton-Raphson method is responsible for the convergence difficulty. A simple,…

Computational Physics · Physics 2020-05-07 Reza Sepasdar , Maryam Shakiba

High fidelity radio interferometric data calibration that minimises spurious spectral structure in the calibrated data is essential in astrophysical applications, such as 21 cm cosmology, which rely on knowledge of the relative spectral…

Instrumentation and Methods for Astrophysics · Physics 2022-10-26 Peter H. Sims , Jonathan C. Pober , Jonathan L. Sievers

Speckle interferometry is an established optical metrology tool for the characterization of rough objects. The raw phase, however, is impaired by the presence of phase singularities, making the unwrapping procedure ambiguous. In a Michelson…

Instrumentation and Detectors · Physics 2016-11-11 Klaus Mantel , Vanusch Nercissian

Modern deep neural networks can produce badly calibrated predictions, especially when train and test distributions are mismatched. Training an ensemble of models and averaging their predictions can help alleviate these issues. We propose a…

Machine Learning · Computer Science 2020-07-09 Asa Cooper Stickland , Iain Murray

NP-hard optimization problems scale very rapidly with problem size, becoming unsolvable with brute force methods, even with supercomputing resources. Typically, such problems have been approximated with heuristics. However, these methods…

Quantum Physics · Physics 2018-03-21 Gideon Bass , Casey Tomlin , Vaibhaw Kumar , Pete Rihaczek , Joseph Dulny

We propose an eigenvector-based formalism for the calibration of radio interferometer arrays. In the presence of a strong dominant point source, the complex gains of the array can be obtained by taking the first eigenvector of the…

Instrumentation and Methods for Astrophysics · Physics 2019-06-14 Shifan Zuo , Ue-Li Pen , Fengquan Wu , Jixia Li , Albert Stebbins , Yougang Wang , Xuelei Chen

We present a new calibration scheme based on a non-linear version of Kalman filter that aims at estimating the physical terms appearing in the Radio Interferometry Measurement Equation (RIME). We enrich the filter's structure with a tunable…

Instrumentation and Methods for Astrophysics · Physics 2015-06-19 Cyril Tasse

Techniques like speckle holography and shearography are rarely applied due to the complexity of instrument setup and lack of automated result analysis, despite their potential. By simulating speckle interferometric outcomes, we seek to…

Optics · Physics 2025-11-25 Jessica Plassmann , Michael Schuth , Georg von Freymann

This manual is intended to help ALMA and other interferometer users improve images by recognising limitations and how to overcome them and deciding when and how to use self-calibration. The images provided by the ALMA Science Archive are…

Instrumentation and Methods for Astrophysics · Physics 2022-07-13 A. M. S. Richards , E. Moravec , S. Etoka , E. B. Fomalont , A. F. Pérez-Sánchez , M. C. Toribio , R. A. Laing

LineStacker is a new open access and open source tool for stacking of spectral lines in interferometric data. LineStacker is an ensemble of CASA tasks, and can stack both 3D cubes or already extracted spectra. The algorithm is tested on…

Astrophysics of Galaxies · Physics 2020-09-30 Jean-Baptiste Jolly , Kirsten K. Knudsen , Flora Stanley

Nonconvex and nonsmooth optimization problems are frequently encountered in much of statistics, business, science and engineering, but they are not yet widely recognized as a technology in the sense of scalability. A reason for this…

Optimization and Control · Mathematics 2018-01-19 Bo Jiang , Tianyi Lin , Shiqian Ma , Shuzhong Zhang

For interpreting the behavior of a probabilistic model, it is useful to measure a model's calibration--the extent to which it produces reliable confidence scores. We address the open problem of calibration for tagging models with sparse…

Computation and Language · Computer Science 2023-05-18 Michael Kranzlein , Nelson F. Liu , Nathan Schneider

We find that the EPE evaluation metrics of RAFT-stereo converge inconsistently in the low and high frequency regions, resulting high frequency degradation (e.g., edges and thin objects) during the iterative process. The underlying reason…

Computer Vision and Pattern Recognition · Computer Science 2025-05-26 Xiaobao Wei , Jiawei Liu , Dongbo Yang , Junda Cheng , Changyong Shu , Wei Wang

In the new perspective of spatial quantization, this article systematically studies the advantages of reconfigurable reflectarray (RRA) designed with closely spaced elements in terms of sidelobe level (SLL), scanning accuracy and scan loss,…

Applied Physics · Physics 2025-02-03 Xiaocun Zong , Fan Yang , Shenheng Xu , Maokun Li

This paper proposes low-complexity robust adaptive beamforming (RAB) techniques based on shrinkage methods. We firstly briefly review a Low-Complexity Shrinkage-Based Mismatch Estimation (LOCSME) batch algorithm to estimate the desired…

Information Theory · Computer Science 2015-12-08 H. Ruan , R. C. de Lamare

We propose a penalized likelihood framework for estimating multiple precision matrices from different classes. Most existing methods either incorporate no information on relationships between the precision matrices, or require this…

Machine Learning · Statistics 2020-03-03 Bradley S. Price , Aaron J. Molstad , Ben Sherwood
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