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Related papers: Tailoring 3D Speckle Statistics

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While optical and quantum efficiency are on the rise, and spectrographs becoming massively multiplexed, measuring spectral energy distributions of astronomical sources with accuracy remains a challenge. In addition to atmospheric…

Solar and Stellar Astrophysics · Physics 2019-03-19 Carlos Allende Prieto

Products between phase-type distributed random variables and any independent, positive and continuous random variable are studied. Their asymptotic properties are established, and an expectation-maximization algorithm for their effective…

Probability · Mathematics 2021-11-25 Hansjoerg Albrecher , Martin Bladt , Mogens Bladt , Jorge Yslas

Line-by-line calculations are becoming the standard procedure for carrying spectral simulations. However, it is important to insure the accuracy of such spectral simulations through the choice of adapted models for the simulation of key…

Optics · Physics 2007-05-23 M. Lino da Silva

We propose a semi-analytical modeling of smoothed laser beams deviation induced by plasma flows. Based on a Gaussian description of speckles, the model includes spatial, temporal and polarization smoothing techniques,through fits issued…

Plasma Physics · Physics 2022-09-05 C. Ruyer , P. Loiseau , G. Riazuelo , R. Riquier , A. Debayle , P. E. Masson-Laborde

Statistical processing of speckle data enables observation of speed of processes. In intensity-based pointwise dynamic speckle analysis, a map related to speed's spatial distribution is extracted from a sequence of speckle patterns formed…

Image and Video Processing · Electrical Eng. & Systems 2023-03-15 Elena Stoykova , Blaga Blagoeva , Natalya Berberova-Buhova , Mikhail Levchenko , Dimana Nazarova , Lian Nedelchev , Joongki Park

The propagation of high-power femtosecond laser pulses in air under conditions of superposed spatial phase modulation is considered theoretically. The numerical simulations are carried out on the basis of the reduced form of nonlinear…

Optics · Physics 2022-01-14 Yury Geints , Olga Minina , Alexander Zemlyanov

We use a simple setup based on an infinite planar slab gain medium with no mirrors to explore the possibility of realizing a recently discovered resonance effect related to the mathematical concept of spectral singularity. In particular we…

Optics · Physics 2010-07-13 Ali Mostafazadeh

The predictability of extreme intensity pulses emitted by an optically injected semiconductor laser is studied numerically, by using a well-known rate equation model. We show that symbolic ordinal time-series analysis allows to identify the…

Data Analysis, Statistics and Probability · Physics 2017-07-03 Nuria Martinez Alvarez , Saurabh Borkar , Cristina Masoller

An imaging refractrometer can be used to describe the properties of a high-energy density plasma by analyzing the transverse intensity distribution of a laser beam that has passed through the plasma. The output of the refractrometer can be…

Plasma Physics · Physics 2025-02-18 A. Rososhek , B. R. Kusse , W. M. Potter , N. J. Wilson , E. S. Lavine , D. A. Hammer

Spectral dimensionality reduction methods enable linear separations of complex data with high-dimensional features in a reduced space. However, these methods do not always give the desired results due to irregularities or uncertainties of…

Machine Learning · Statistics 2018-05-21 Momo Matsuda , Keiichi Morikuni , Tetsuya Sakurai

This paper proposes the design of decision models based on Computational Intelligence techniques applied to image sequences of dynamic laser speckle. These models aim to identify image regions of biological specimens illuminated by a…

In recent years there has been a resurgence of interest in our community in the shape analysis of 3D objects represented by surface meshes, their voxelized interiors, or surface point clouds. In part, this interest has been stimulated by…

Computer Vision and Pattern Recognition · Computer Science 2021-12-01 Morteza Rezanejad , Mohammad Khodadad , Hamidreza Mahyar , Herve Lombaert , Michael Gruninger , Dirk B. Walther , Kaleem Siddiqi

The use of neural networks to directly predict three-dimensional dose distributions for automatic planning is becoming popular. However, the existing methods only use patient anatomy as input and assume consistent beam configuration for all…

Stimulated Emission Depletion (STED) microscopy has emerged as a powerful technique providing visualization of biological structures at the molecular level in living samples. In this technique, the diffraction limit is broken by selectively…

Machine Learning and Deep Learning are computational tools that fall within the domain of artificial intelligence. In recent years, numerous research works have advanced the application of machine and deep learning in various fields,…

In this Chapter we review the challenges of, and opportunities for, 3D spectroscopy, and how these have lead to new and different approaches to sampling astronomical information. We describe and categorize existing instruments on 4m and 10m…

Instrumentation and Methods for Astrophysics · Physics 2009-10-02 Matthew A. Bershady

This paper presents a new approach for filter design based on stochastic distances and tests between distributions. A window is defined around each pixel, overlapping samples are compared and only those which pass a goodness-of-fit test are…

Information Theory · Computer Science 2013-08-30 Leonardo Torres , Tamer Cavalcante , Alejandro C. Frery

Speckle patterns are inherent features of coherent light propagation through complex media. As a result of interference, they are sensitive to multiple experimental parameters such as the configuration of disorder or the propagating…

Current observations stimulate the production of fully three-dimensional explosion models, which in turn motivates three-dimensional spectrum synthesis for supernova atmospheres. We briefly discuss techniques adapted to address the latter…

Astrophysics · Physics 2007-05-23 R. C. Thomas

Nonlinear optical methods are becoming ubiquitous in many areas of modern photonics. They are, however, often limited to a certain range of input parameters, such as pulse energy and average power, since restrictions arise from, for…