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Related papers: Sampling in Thermoacoustic Tomography

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We study the mathematical model of thermoacoustic tomography in media with a variable speed for a fixed time interval, greater than the diameter of the domain. In case of measurements on the whole boundary, we give an explicit solution in…

Analysis of PDEs · Mathematics 2010-09-10 Plamen Stefanov , Gunther Uhlmann

The time reversal method in thermoacoustic tomography is used for approximating the initial pressure inside a biological object using measurements of the pressure wave made on a surface surrounding the object. This article presents error…

Analysis of PDEs · Mathematics 2009-03-18 Yulia Hristova

The vast majority of sampling systems operate in a standard way: at each tick of a fixed-frequency master clock a digitizer reads out a voltage that corresponds to the value of some physical quantity and translates it into a bit pattern…

Data Analysis, Statistics and Probability · Physics 2009-11-13 Edoardo Milotti

Pixel-wise predictions are required in a wide variety of tasks such as image restoration, image segmentation, or disparity estimation. Common models involve several stages of data resampling, in which the resolution of feature maps is first…

Computer Vision and Pattern Recognition · Computer Science 2024-07-16 Shashank Agnihotri , Julia Grabinski , Margret Keuper

Microelectromechanical systems (MEMS) gyroscopes are widely used, e.g. in modern automotive and consumer applications, and require signal stability and accuracy in rather harsh environmental conditions. In many use cases, device reliability…

Mesoscale and Nanoscale Physics · Physics 2024-01-29 Daniel Schiwietz , Eva M. Weig , Peter Degenfeld-Schonburg

Sampling is a pivotal element in the design of metasurfaces, enabling a broad spectrum of applications. Despite its flexibility, sampling can result in reduced efficiency and unintended diffractions, which are more pronounced at high…

Optics · Physics 2024-06-18 Seokwoo Kim , Joohoon Kim , Kyungtae Kim , Minsu Jeong , Junsuk Rho

The frequency at which a large space telescope's (e.g. NGST's) detector chips are read, or the sample rate, is tightly coupled to many hardware and operational aspects of the telescope's instrument and data handling elements. In this paper…

Astrophysics · Physics 2009-11-07 D. J. Fixsen , R. H. Cornett

Sampling a signal below the Shannon-Nyquist rate causes aliasing, meaning different frequencies to become indistinguishable. It is also well-known that recovering spectral information from a signal using a parametric method can be ill-posed…

Numerical Analysis · Mathematics 2018-10-09 Annie Cuyt , Wen-shin Lee

Advances in techniques for thermal sampling in classical and quantum systems would deepen understanding of the underlying physics. Unfortunately, one often has to rely solely on inexact numerical simulation, due to the intractability of…

Quantum Physics · Physics 2020-04-10 Jeffrey Marshall , Andrea Di Gioacchino , Eleanor G. Rieffel

A practical constraint that comes in the way of spectrum estimation of a continuous time stationary stochastic process is the minimum separation between successively observed samples of the process. When the underlying process is not…

Statistics Theory · Mathematics 2011-06-23 Radhendushka Srivastava , Debasis Sengupta

We consider the problem of reconstructing a wide sense stationary band-limited process from its local averages taken either at the Nyquist rate or above. As a result, we obtain a sufficient condition under which average sampling expansions…

Information Theory · Computer Science 2012-11-29 Gilles Faÿ , Sinuk Kang

In many applications of frequency estimation, the frequencies of the signals are so high that the data sampled at Nyquist rate are hard to acquire due to hardware limitation. In this paper, we propose a novel method based on subspace…

Information Theory · Computer Science 2015-08-27 Shan Huang , Hong Sun , Lei Yu , Haijian Zhang

We study the mathematical model of thermoacoustic and photoacoustic tomography when the sound speed has a jump across a smooth surface. This models the change of the sound speed in the skull when trying to image the human brain. We derive…

Analysis of PDEs · Mathematics 2015-05-19 Plamen Stefanov , Gunther Uhlmann

The sampling rate of input and output signals is known to play a critical role in the identification and control of dynamical systems. For slow-sampled continuous-time systems that do not satisfy the Nyquist-Shannon sampling condition for…

Systems and Control · Electrical Eng. & Systems 2024-10-28 Rodrigo A. González , Max van Haren , Tom Oomen , Cristian R. Rojas

The article starts with new aliasing-truncation error upper bounds in the sampling theorem for non-bandlimited stochastic signals. Then, it investigates $L_p([0,T])$ approximations of sub-Gaussian random signals. Explicit truncation error…

Information Theory · Computer Science 2016-08-15 Yuriy Kozachenko , Andriy Olenko

Imaging devices exploit the Nyquist-Shannon sampling theorem to avoid both aliasing and redundant oversampling by design. Conversely, in medical image resampling, images are considered as continuous functions, are warped by a spatial…

Image and Video Processing · Electrical Eng. & Systems 2021-01-19 M. Jorge Cardoso , Marc Modat , Tom Vercauteren , Sebastien Ourselin

This paper concerns thermoacoustic tomography and photoacoustic tomography, two couple-physics imaging modalities that attempt to combine the high resolution of ultrasound and the high contrast capabilities of electromagnetic waves. We give…

Analysis of PDEs · Mathematics 2015-09-30 Hongyu Liu , Gunther Uhlmann

Stochastic texture filtering (STF) has re-emerged as a technique that can bring down the cost of texture filtering of advanced texture compression methods, e.g., neural texture compression. However, during texture magnification, the swapped…

Graphics · Computer Science 2025-04-09 Bartlomiej Wronski , Matt Pharr , Tomas Akenine-Möller

This article studies the convergence rate of the sample mean for $\varphi$-mixing dependent random variables with finite means and infinite variances. Dividing the sample mean into sum of the average of the main parts and the average of the…

Probability · Mathematics 2022-09-20 F. Q. Tang , D. Han

Upsampling artifacts are caused by problematic upsampling layers and due to spectral replicas that emerge while upsampling. Also, depending on the used upsampling layer, such artifacts can either be tonal artifacts (additive high-frequency…

Sound · Computer Science 2021-11-24 Jordi Pons , Joan Serrà , Santiago Pascual , Giulio Cengarle , Daniel Arteaga , Davide Scaini
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