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Related papers: Extracting the Spectrum by Spatial Filtering

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We put forward a new type of spectral method for the direct numerical simulation of flows where anisotropy or very fine boundary layers are present. The mean idea is to take advantage of the fact that such structures are dissipative and…

Fluid Dynamics · Physics 2014-03-18 Kacper Kornet , Alban Pothérat

Accessing the electric field of light with petahertz bandwidths in ambient air is a rapidly advancing frontier, essential for probing ultrafast dynamics driven by classical or quantum ultrashort pulses. Near-petahertz fieldoscopy has…

The time-dependent surface flux (t-SURFF) method is introduced for computing of strong-field infrared photo-ionization spectra of atoms by numerically solving the time-dependent Schr\"odinger equation on minimal simulation volumes. The…

Computational Physics · Physics 2015-05-30 Liang Tao , Armin Scrinzi

Real time, singleshot multispectral imaging systems are crucial for environment monitoring and biomedical imaging. Most singleshot multispectral imagers rely on complex computational backends, which precludes real time operations. In this…

Optics · Physics 2025-02-27 Romil Audhkhasi , Ningzhi Xie , Johannes E. Fröch , Arka Majumdar

The phase of the electronic wave function is not directly measurable but, quite remarkably, it becomes accessible in pairs of isospectral shapes, as recently proposed in the experiment of Christopher R. Moon {\it et al.}, Science {\bf 319},…

Mesoscale and Nanoscale Physics · Physics 2015-06-04 Mugurel Ţolea , Bogdan Ostahie , Marian Niţă , Felicia Ţolea , Alexandru Aldea

Recovering the wavelength from disordered speckle patterns has become an exciting prospect as a wavelength measurement method due to its high resolution and simple design. In previous studies, panel cameras have been used to detect the…

Instrumentation and Detectors · Physics 2023-08-14 Tianliang Wang , Yi Li , Xinyu Gao , Jinchao Tao , Xu Wang , Qin Liang , Yanqing Qiu , Bangning Mao , Yanlong Meng

We propose a simple method to deconvolute NMR spectra of quadrupolar nuclei in order to separate the distribution of local magnetic hyperfine field from the quadrupole splitting. It is based on an iterative procedure which allows to express…

Strongly Correlated Electrons · Physics 2013-07-09 Mila Frederic , Takigawa Masashi

We present a novel diffusion-based framework for synthesizing 2D vector fields from sparse, coherent inputs (i.e., streamlines) while maintaining physical plausibility. Our method employs a conditional denoising diffusion probabilistic…

Computer Vision and Pattern Recognition · Computer Science 2026-04-14 Nguyen K. Phan , Ricardo Morales , Sebastian D. Espriella , Guoning Chen

Accurate spatio-temporal and spatio-spectral metrology is critical to the characterization and use of ultra-short, high-power lasers. The emergence of few cycle pulses, with bandwidths of tens or hundreds of nanometers, poses a significant…

Linear shear flow bounded by a plane wall is an idealization that occurs in microfluidic devices and many other applications. Perfect plane approximation neglects surface irregularities and discrete particles adsorbed at the surface. Here…

Fluid Dynamics · Physics 2024-05-28 Itzhak Fouxon , Alexander M. Leshansky

Image subtraction is essential for transient detection in time-domain astronomy. The point spread function (PSF), photometric scaling, and sky background generally vary with time and across the field-of-view for imaging data taken with…

Instrumentation and Methods for Astrophysics · Physics 2022-09-14 Lei Hu , Lifan Wang , Xingzhuo Chen , Jiawen Yang

The paper studies properties of continuous time processes with spectrum degeneracy at a single point where their Fourier transforms vanish with a certain rate. It appears that these processes are linearly predictable in some weak sense,…

Information Theory · Computer Science 2020-01-10 Nikolai Dokuchaev

Hyperspectral imaging is a powerful technology that is plagued by large dimensionality. Herein, we explore a way to combat that hindrance via non-contiguous and contiguous (simpler to realize sensor) band grouping for dimensionality…

Image and Video Processing · Electrical Eng. & Systems 2019-05-31 Muhammad Aminul Islam , Derek T. Anderson , John E. Ball , Nicolas H. Younan

We introduce a continuous domain framework for the recovery of points on a surface in high dimensional space, represented as the zero-level set of a bandlimited function. We show that the exponential maps of the points on the surface…

Computer Vision and Pattern Recognition · Computer Science 2018-03-21 Sunrita Poddar , Mathews Jacob

Spectrum sensing and analysis is crucial for a variety of reasons, including regulatory compliance, interference detection and mitigation, and spectrum resource planning and optimization. Effective, real-time spectrum analysis remains a…

Signal Processing · Electrical Eng. & Systems 2026-01-21 Rahil Gandotra , Ruoyu Sun , Mark Poletti , Jiayu Mao , Hao Guo

Median filtering is a cornerstone of computational image processing. It provides an effective means of image smoothing, with minimal blurring or softening of edges, invariance to monotonic transformations such as gamma adjustment, and…

Computer Vision and Pattern Recognition · Computer Science 2025-05-30 Ben Weiss

In this work, we extract the optical flow field corresponding to moving objects from an image sequence of a scene impacted by atmospheric turbulence \emph{and} captured from a moving camera. Our procedure first computes the optical flow…

Computer Vision and Pattern Recognition · Computer Science 2024-10-30 Nicholas Ferrante , Jerome Gilles , Shibin Parameswaran

We have developed a new method that uses wavelet analysis to remove interference fringe patterns from images. This method is particularly useful for flat fields in the common case where fringes vary between the calibration and object data.…

Astrophysics · Physics 2008-11-26 Patricio Rojo , Joseph Harrington

It is well-known that spatial averaging can be realized (in space or frequency domain) using algorithms whose complexity does not depend on the size or shape of the filter. These fast algorithms are generally referred to as constant-time or…

Computer Vision and Pattern Recognition · Computer Science 2013-07-23 Kunal Narayan Chaudhury , Daniel Sage , Michael Unser

For many of the physical phenomena around us, we have developed sophisticated models explaining their behavior. Nevertheless, inferring specifics from visual observations is challenging due to the high number of causally underlying physical…

Computer Vision and Pattern Recognition · Computer Science 2019-10-18 Tom F. H. Runia , Kirill Gavrilyuk , Cees G. M. Snoek , Arnold W. M. Smeulders