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Related papers: Chordal Decomposition for Spectral Coarsening

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Graph coarsening is a widely used dimensionality reduction technique for approaching large-scale graph machine learning problems. Given a large graph, graph coarsening aims to learn a smaller-tractable graph while preserving the properties…

Machine Learning · Statistics 2022-10-04 Manoj Kumar , Anurag Sharma , Sandeep Kumar

This work investigates the empirical performance of the sparse synthesis versus sparse analysis regularization for the ill-posed inverse problem of audio declipping. We develop a versatile non-convex heuristics which can be readily used…

Sound · Computer Science 2015-06-10 Srđan Kitić , Nancy Bertin , Rémi Gribonval

This study presents band-ensemble Spectral Proper Orthogonal Decomposition (bSPOD). The approach is inspired by frequency smoothing, a method used to reduce estimator variance in power spectral density estimates, and is here extended to…

The signal demixing problem seeks to separate a superposition of multiple signals into its constituent components. This paper studies a two-stage approach that first decompresses and subsequently deconvolves the noisy and undersampled…

Information Retrieval · Computer Science 2022-05-25 Zhenan Fan , Halyun Jeong , Babhru Joshi , Michael P. Friedlander

In the context of next generation radio telescopes, like the Square Kilometre Array, the efficient processing of large-scale datasets is extremely important. Convex optimisation tasks under the compressive sensing framework have recently…

Instrumentation and Methods for Astrophysics · Physics 2016-08-10 Alexandru Onose , Rafael E. Carrillo , Audrey Repetti , Jason D. McEwen , Jean-Philippe Thiran , Jean-Christophe Pesquet , Yves Wiaux

In this paper we analyze several new methods for solving nonconvex optimization problems with the objective function formed as a sum of two terms: one is nonconvex and smooth, and another is convex but simple and its structure is known.…

Optimization and Control · Mathematics 2014-06-25 A. Patrascu , I. Necoara

Image optimization problems encompass many applications such as spectral fusion, deblurring, deconvolution, dehazing, matting, reflection removal and image interpolation, among others. With current image sizes in the order of megabytes, it…

Computer Vision and Pattern Recognition · Computer Science 2018-09-13 Majed El Helou , Frederike Dümbgen , Radhakrishna Achanta , Sabine Süsstrunk

Sparsity in the eigenvectors of signal covariance matrices is exploited in this paper for compression and denoising. Dimensionality reduction (DR) and quantization modules present in many practical compression schemes such as transform…

Applications · Statistics 2015-06-03 Ioannis D. Schizas , Georgios B. Giannakis

Compatible Discrete Operator schemes preserve basic properties of the continuous model at the discrete level. They combine discrete differential operators that discretize exactly topological laws and discrete Hodge operators that…

Numerical Analysis · Mathematics 2014-01-31 Jerome Bonelle , Alexandre Ern

Spectral discretizations of fractional derivative operators are examined, where the approximation basis is related to the set of Jacobi polynomials. The pseudo-spectral method is implemented by assuming that the grid, used to represent the…

Numerical Analysis · Mathematics 2018-03-29 Lorella Fatone , Daniele Funaro

This paper establishes optimal convergence rates for estimation of structured covariance operators of Gaussian processes. We study banded operators with kernels that decay rapidly off-the-diagonal and $L^q$-sparse operators with an…

Statistics Theory · Mathematics 2025-07-01 Omar Al-Ghattas , Jiaheng Chen , Daniel Sanz-Alonso , Nathan Waniorek

We propose a new method for generating semidefinite relaxations of optimal power flow problems. The method is based on chordal conversion techniques: by dropping some equality constraints in the conversion, we obtain semidefinite…

Optimization and Control · Mathematics 2013-12-09 Martin S. Andersen , Anders Hansson , Lieven Vandenberghe

We study the structure of the set of algebraic curvature operators satisfying a sectional curvature bound under the light of the emerging field of Convex Algebraic Geometry. More precisely, we determine in which dimensions $n$ this convex…

Differential Geometry · Mathematics 2021-05-14 Renato G. Bettiol , Mario Kummer , Ricardo A. E. Mendes

High-dimensional simulation optimization is notoriously challenging. We propose a new sampling algorithm that converges to a global optimal solution and suffers minimally from the curse of dimensionality. The algorithm consists of two…

Machine Learning · Statistics 2021-07-21 Liang Ding , Rui Tuo , Xiaowei Zhang

Diffractive lenses have recently been applied to the domain of multispectral imaging in the X-ray and UV regimes where they can achieve very high resolution as compared to reflective and refractive optics. Conventionally, spectral…

Image and Video Processing · Electrical Eng. & Systems 2020-05-26 Evan Widloski , Ulas Kamaci , Farzad Kamalabadi

Multi-sector capacity expansion models play a crucial role in energy planning by providing decision support for policymaking in technology development. To ensure reliable support, these models require high technological, spatial, and…

Optimization and Control · Mathematics 2025-04-14 Federico Parolin , Yu Weng , Paolo Colbertaldo , Ruaridh Macdonald

We propose and investigate a mesh deformation technique for PDE constrained shape optimization. Introducing a gradient penalization to the inner product for linearized shape spaces, mesh degeneration can be prevented within the optimization…

Optimization and Control · Mathematics 2021-06-09 Martin Siebenborn , Andreas Vogel

This paper proposes and analyzes a new operator splitting method for stochastic Maxwell equations driven by additive noise, which not only decomposes the original multi-dimensional system into some local one-dimensional subsystems, but also…

Numerical Analysis · Mathematics 2021-02-23 Chuchu Chen , Jialin Hong , Lihai Ji

We investigate the task of retrieving information from compositional distributed representations formed by Hyperdimensional Computing/Vector Symbolic Architectures and present novel techniques which achieve new information rate bounds.…

Neural and Evolutionary Computing · Computer Science 2023-05-29 Denis Kleyko , Connor Bybee , Ping-Chen Huang , Christopher J. Kymn , Bruno A. Olshausen , E. Paxon Frady , Friedrich T. Sommer

Signal decomposition and multiscale signal analysis provide many useful tools for time-frequency analysis. We proposed a random feature method for analyzing time-series data by constructing a sparse approximation to the spectrogram. The…

Signal Processing · Electrical Eng. & Systems 2023-03-17 Nicholas Richardson , Hayden Schaeffer , Giang Tran