English
Related papers

Related papers: Sparse reconstruction in spin systems I: iid spins

200 papers

In this paper, we derive a new reconstruction method for real non-harmonic Fourier sums, i.e., real signals which can be represented as sparse exponential sums of the form $f(t) = \sum_{j=1}^{K} \gamma_{j} \, \cos(2\pi a_{j} t + b_{j})$,…

Numerical Analysis · Mathematics 2020-11-30 Markus Petz , Gerlind Plonka , Nadiia Derevianko

This paper introduces an elasticity reconstruction method based on local displacement observations of elastic bodies. Sparse reconstruction theory is applied to formulate the underdetermined inverse problems of elasticity reconstruction…

Machine Learning · Computer Science 2019-02-26 Megumi Nakao , Mitsuki Morita , Tetsuya Matsuda

In this thesis we discuss machine learning methods performing automated variable selection for learning sparse predictive models. There are multiple reasons for promoting sparsity in the predictive models. By relying on a limited set of…

Machine Learning · Computer Science 2019-03-27 Magda Gregorova

Even though image signals are typically defined on a regular two-dimensional grid, there also exist many scenarios where this is not the case and the amplitude of the image signal only is available for a non-regular subset of pixel…

Image and Video Processing · Electrical Eng. & Systems 2022-04-28 Jürgen Seiler , Markus Jonscher , Michael Schöberl , André Kaup

We present a novel method for the classification and reconstruction of time dependent, high-dimensional data using sparse measurements, and apply it to the flow around a cylinder. Assuming the data lies near a low dimensional manifold…

Dynamical Systems · Mathematics 2015-06-03 Ido Bright , Guang Lin , J. Nathan Kutz

Functional time series analysis, whether based on time of frequency domain methodology, has traditionally been carried out under the assumption of complete observation of the constituent series of curves, assumed stationary. Nevertheless,…

Methodology · Statistics 2020-04-02 Tomáš Rubín , Victor M. Panaretos

The paper observes the Hermite and the Fourier Transform domains in terms of Frequency Hopping Spread Spectrum signals sparsification. Sparse signals can be recovered from a reduced set of samples by using the Compressive Sensing approach.…

Signal Processing · Electrical Eng. & Systems 2018-02-15 Valentina Konatar , Maja Vesovic

We present a data-driven model to reconstruct nonlinear dynamics from a very sparse times series data, which relies on the strength of the echo state network (ESN) in learning nonlinear representation of data. With an assumption of the…

Neural and Evolutionary Computing · Computer Science 2019-07-24 Kyongmin Yeo

A robust algorithm is proposed to reconstruct the spatial support and the Lam\'e parameters of multiple inclusions in a homogeneous background elastic material using a few measurements of the displacement field over a finite collection of…

Numerical Analysis · Mathematics 2017-02-27 Jaejun Yoo , Younghoon Jung , Mikyoung Lim , Jong Chul Ye , Abdul Wahab

We propose an algorithm for rotational sparse coding along with an efficient implementation using steerability. Sparse coding (also called dictionary learning) is an important technique in image processing, useful in inverse problems,…

Image and Video Processing · Electrical Eng. & Systems 2020-01-31 Michael T. McCann , Vincent Andrearczyk , Michael Unser , Adrien Depeursinge

This paper introduces a novel framework and corresponding methods for sampling and reconstruction of sparse signals in shift-invariant (SI) spaces. We reinterpret the random demodulator, a system that acquires sparse bandlimited signals, as…

Signal Processing · Electrical Eng. & Systems 2022-01-24 Tin Vlašić , Damir Seršić

Bottleneck autoencoders have been actively researched as a solution to image compression tasks. However, we observed that bottleneck autoencoders produce subjectively low quality reconstructed images. In this work, we explore the ability of…

Computer Vision and Pattern Recognition · Computer Science 2018-01-25 Yijing Watkins , Mohammad Sayeh , Oleksandr Iaroshenko , Garrett Kenyon

Converting an n-dimensional vector to a probability distribution over n objects is a commonly used component in many machine learning tasks like multiclass classification, multilabel classification, attention mechanisms etc. For this,…

We study high-dimensional sparse estimation under three natural constraints: communication constraints, local privacy constraints, and linear measurements (compressive sensing). Without sparsity assumptions, it has been established that…

Data Structures and Algorithms · Computer Science 2022-03-15 Jayadev Acharya , Clément L. Canonne , Ziteng Sun , Himanshu Tyagi

Trajectory reconstruction is the process of inferring the path of a moving object between successive observations. In this paper, we propose a smoothing spline -- which we name the V-spline -- that incorporates position and velocity…

Methodology · Statistics 2022-06-20 Zhanglong Cao , David Bryant , Tim Molteno , Colin Fox , Matthew Parry

We study reconstruction operators on a Hilbert space that are exact on a given reconstruction subspace. Among those the reconstruction operator obtained by the least squares fit has the smallest operator norm, and therefore is most stable…

Numerical Analysis · Mathematics 2019-09-18 Peter Berger , Karlheinz Gröchenig , Gerald Matz

In this paper, we study the issue of estimating a structured signal $x_0 \in \mathbb{R}^n$ from non-linear and noisy Gaussian observations. Supposing that $x_0$ is contained in a certain convex subset $K \subset \mathbb{R}^n$, we prove that…

Statistics Theory · Mathematics 2017-02-21 Martin Genzel

In many real-world inverse problems, only incomplete measurement data are available for training which can pose a problem for learning a reconstruction function. Indeed, unsupervised learning using a fixed incomplete measurement process is…

Machine Learning · Statistics 2022-09-30 Julián Tachella , Dongdong Chen , Mike Davies

Inversion codes are numerical tools used for the inference of physical properties from the observations. Despite their success, the quality of current spectropolarimetric observations and those expected in the near future presents a…

Solar and Stellar Astrophysics · Physics 2015-05-27 A. Asensio Ramos , J. de la Cruz Rodriguez

We propose a systematic method for constructing a sparse data reconstruction algorithm in compressed sensing at a relatively low computational cost for general observation matrix. It is known that the cost of l1-norm minimization using a…

Information Theory · Computer Science 2014-04-10 Koujin Takeda , Yoshiyuki Kabashima