English
Related papers

Related papers: Sparse Modeling analysis of Extended X-ray Absorpt…

200 papers

We model the absorption of X-rays by gas obscuring the source and photoionized by it. We consider a broad range of column densities, including both Thomson-thin and Thomson-thick media. For the Thomson thin regime, we derive a simple…

High Energy Astrophysical Phenomena · Physics 2026-04-08 Taya Govreen-Segal , Ehud Nakar , Eliot Quataert

Compressed sensing is designed to measure sparse signals directly in a compressed form. However, most signals of interest are only "approximately sparse", i.e. even though the signal contains only a small fraction of relevant (large)…

Information Theory · Computer Science 2013-04-04 Jean Barbier , Florent Krzakala , Marc Mézard , Lenka Zdeborová

Approximate message-passing (AMP) method is a simple and efficient framework for the linear inverse problems. In this letter, we propose a faster AMP to solve the \emph{$L_1$-Split-Analysis} for the 2D sparsity separation, which is referred…

Information Theory · Computer Science 2015-07-13 Jaewook Kang , Hyoyoung Jung , Kiseon Kim

The characterization of nanostructured surfaces with sensitivity in the sub-nm range is of high importance for the development of current and next generation integrated electronic circuits. Modern transistor architectures for e.g. FinFETs…

This paper provides a mathematical analysis of ultrafast ultrasound imaging. This newly emerging modality for biomedical imaging uses plane waves instead of focused waves in order to achieve very high frame rates. We derive the point spread…

Numerical Analysis · Mathematics 2017-01-09 Giovanni S. Alberti , Habib Ammari , Francisco Romero , Timothée Wintz

Consider a regression model with fixed design and Gaussian noise where the regression function can potentially be well approximated by a function that admits a sparse representation in a given dictionary. This paper resorts to exponential…

Statistics Theory · Mathematics 2013-01-08 Philippe Rigollet , Alexandre B. Tsybakov

Electron and scanning probe microscopy produce vast amounts of data in the form of images or hyperspectral data, such as EELS or 4D STEM, that contain information on a wide range of structural, physical, and chemical properties of…

Machine Learning · Computer Science 2023-06-09 Arpan Biswas , Maxim Ziatdinov , Sergei V. Kalinin

In this paper, we derive an effective model for transport processes in periodically perforated elastic media, taking into account, e.g., cyclic elastic deformations as they occur in lung tissue due to respiratory movement. The underlying…

Analysis of PDEs · Mathematics 2022-06-15 Jonas Knoch , Markus Gahn , Maria Neuss-Radu , Nicolas Neuß

We propose a high signal-to-noise extended depth-range three-dimensional (3D) profilometer projecting two linear-fringes with close phase-sensitivity. We use temporal phase-shifting algorithms (PSAs) to phase-demodulate the two close…

Optics · Physics 2018-04-04 Manuel Servin , Moises Padilla , Guillermo Garnica

We describe an approach based on compressive-sampling which allows for a considerable reduction in the acquisition time in Fourier-transform spectroscopy. In this approach, an N-point Fourier spectrum is resolved from much less than N…

Optics · Physics 2010-06-15 Ori Katz , Jonathan M. Levitt , Yaron Silberberg

We study the propagation of waves in a set of absorbing subwavelength scatterers positioned on a stealth hyperuniform point pattern. We show that spatial correlations in the disorder substantially enhance absorption compared to a fully…

Optics · Physics 2019-03-27 Florian Bigourdan , Romain Pierrat , Rémi Carminati

In the quantitative analysis of Dynamic Contrast-Enhanced Magnetic Resonance Imaging (DCE-MRI) compartment models allow to describe the uptake of contrast medium with biological meaningful kinetic parameters. As simple models often fail to…

Methodology · Statistics 2020-05-04 Julia C. Sommer , Volker J. Schmid

Shape-constrained functional data encompass a wide array of application fields, such as activity profiling, growth curves, healthcare and mortality. Most existing methods for general functional data analysis often ignore that such data are…

Methodology · Statistics 2024-08-13 Poorbita Kundu , Hans-Georg Müller

Ultrasound imaging is widely used in noninvasive medical diagnostics due to its efficiency, portability, and avoidance of ionizing radiation. However, its utility is limited by the quality of the signal. Signal-dependent speckle noise,…

Image and Video Processing · Electrical Eng. & Systems 2026-02-10 Soumee Guha , Scott T. Acton

In an ultrasonic array system, increasing the aperture size to achieve a high resolution requires more transmit and receive channels, thus making it essential to have an analysis technique that can reconstruct the shape and physical…

Optics · Physics 2025-08-21 Kai Yabumoto , Takayoshi Yumii , Kenjiro Kimura

High real-space resolution atomic pair distribution functions (PDF)s from the alloy series Ga_1-xIn_xAs have been obtained using high-energy x-ray diffraction. The first peak in the PDF is resolved as a doublet due to the presence of two…

Materials Science · Physics 2012-03-28 V. Petkov , I-K. Jeong , J. S. Chung , M. F. Thorpe , S. Kycia , S. J. L. Billinge

We consider the compressive sensing of a sparse or compressible signal ${\bf x} \in {\mathbb R}^M$. We explicitly construct a class of measurement matrices, referred to as the low density frames, and develop decoding algorithms that produce…

Information Theory · Computer Science 2009-03-05 Mehmet Akçakaya , Jinsoo Park , Vahid Tarokh

In this second part of a series we attempt to construct an empirical model that can mimick all experimental observations made regarding the role of an alternative interleaved scan pattern in STEM imaging on the beam damage in a specific…

Materials Science · Physics 2021-05-03 D. Jannis , A. Velazco , A. Béché , J. Verbeeck

Biological soft tissues encountered in clinical and pre-clinical imaging mainly consist of light element atoms, and their composition is nearly uniform with little density variation. Thus, x-ray attenuation imaging suffers from low image…

Medical Physics · Physics 2011-06-28 Wenxiang Cong , Atsushi Momose , Ge Wang

The unprecedented X-ray flux density provided by modern X-ray sources offers new spatiotemporal possibilities for X-ray imaging of fast dynamic processes. Approaches to exploit such possibilities often result in either i) a limited number…

Image and Video Processing · Electrical Eng. & Systems 2025-04-07 Zisheng Yao , Yuhe Zhang , Zhe Hu , Robert Klöfkorn , Tobias Ritschel , Pablo Villanueva-Perez