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Useful information (UI) is an elusive concept in neural networks. A quantitative measurement of UI is absent, despite the variations of UI can be recognized by prior knowledge. The communication bandwidth of feature maps decreases after…

Computer Vision and Pattern Recognition · Computer Science 2024-10-28 Yunkai Yu , Yuyang You , Zhihong Yang , Guozheng Liu , Peiyao Li , Zhicheng Yang , Wenjing Shan

The feature based spatial verification method SAL is applied to cloud data, i.e. two-dimensional spatial fields of total cloud cover and spectral radiance. Model output is obtained from the COSMO-DE forward operator SynSat and compared to…

Atmospheric and Oceanic Physics · Physics 2016-03-08 Michael Weniger , Petra Friederichs

Unsupervised change detection techniques are generally constrained to two multi-band optical images acquired at different times through sensors sharing the same spatial and spectral resolution. This scenario is suitable for a straight…

Image and Video Processing · Electrical Eng. & Systems 2018-04-10 Vinicius Ferraris , Nicolas Dobigeon , Marie Chabert

High resolution imaging is achieved using increasingly larger apertures and successively shorter wavelengths. Optical aperture synthesis is an important high-resolution imaging technology used in astronomy. Conventional long baseline…

The effect of random surface roughness on hydrodynamics of viscous incompressible liquid is discussed. Roughness-driven contributions to hydrodynamic flows, energy dissipation, and friction force are calculated in a wide range of…

Soft Condensed Matter · Physics 2009-11-07 I. V. Ponomarev , A. E. Meyerovich

This paper presents a new numerical model based on the highly nonlinear potential flow theory for simulating the propagation of water waves in variable depth. A new set of equations for estimating the surface vertical velocity is derived…

Fluid Dynamics · Physics 2024-12-02 Jinghua Wang

Random surface deviations in a reflector antenna reduce the aperture efficiency. This communication presents a method for estimating the mean surface deviation of a parabolic reflector from a set of measured points. The proposed method…

Instrumentation and Methods for Astrophysics · Physics 2010-07-28 Nicolás A. Casco

This paper is concerned with inverse scattering of plane waves by a locally perturbed infinite plane (which is called a locally rough surface) with the modulus of the total-field data (also called the phaseless near-field data) at a fixed…

Numerical Analysis · Mathematics 2018-08-28 Xiaoxu Xu , Bo Zhang , Haiwen Zhang

In the present manuscript, we consider the practical problem of wave interaction with a vertical wall. However, the novelty here consists in the fact that the wall can move horizontally due to a system of springs. The water wave evolution…

Fluid Dynamics · Physics 2020-02-20 Gayaz Khakimzyanov , Denys Dutykh

This paper presents the analysis of metasurfaces, here called reconfigurable intelligent surface. The analysis is performed by numerical simulations that implement the finite-difference time-domain method. The metasurface has been modeled…

Applied Physics · Physics 2023-09-25 Emanuel Colella , Luca Bastianelli , Valter Mariani Primiani , Franco Moglie

All optical systems, which involve the collimation of a reflected, transmitted or scattered wave subsequent to tight focusing, are subject to two kinds of deviations. One is the wavefront curvature due to inaccurate focal placement of the…

Optics · Physics 2024-06-10 Nitish Kumar , Anirban Debnath , Nirmal K. Viswanathan

For more than 150 years, scientists have advanced aberration theory to describe, analyse, and eliminate imperfections that disturb the imaging quality of optical components and systems. Simultaneously, they have developed optical design…

Optics · Physics 2021-06-01 Fabian Duerr , Hugo Thienpont

Single-wavelength interferometry achieves high resolution for smooth surfaces but struggles with rough, industrially relevant ones due to limited unambiguous measuring range and speckle effects. Multi-wavelength interferometry addresses…

Observations of the solar surface reveal the presence of flows with length scales of around $35$ Mm, commonly referred to as supergranules. Inferring the sub-surface flow profile of supergranules from measurements of the surface and…

Solar and Stellar Astrophysics · Physics 2016-08-03 Jishnu Bhattacharya , Shravan M. Hanasoge

Understanding the contact between rough surfaces undergoing plastic deformation is crucial in many applications. We study the effect of plastic deformation on the surface separation between two solids with random roughness. Assuming a…

Soft Condensed Matter · Physics 2026-01-07 Andreas Almqvist , Bo N. J. Persson

Analytical contact mechanics theories depend on surface roughness through the surface roughness power spectrum. In the present study, we evaluated the usability of various experimental methods for studying surface roughness. Our findings…

Materials Science · Physics 2024-08-13 N. Rodriguez , L. Gontard , C. Ma , R. Xu , B. N. J. Persson

This paper explores optimal methods for obtaining one-dimensional (1D) powder pattern intensities from two-dimensional (2D) planar detectors with good estimates of their standard deviations. We describe methods to estimate uncertainties…

Materials Science · Physics 2014-09-12 Xiaohao Yang , Pavol Juhas , Simon J. L. Billinge

Randomly sampling points on surfaces is an essential operation in geometry processing. This sampling is computationally straightforward on explicit meshes, but it is much more difficult on other shape representations, such as widely-used…

Graphics · Computer Science 2025-06-16 Selena Ling , Abhishek Madan , Nicholas Sharp , Alec Jacobson

Wavefront estimation is an essential component of adaptive optics where the goal is to recover the underlying phase from its Fourier magnitude. While this may sound identical to classical phase retrieval, wavefront estimation faces more…

Signal Processing · Electrical Eng. & Systems 2025-04-15 Nicholas Chimitt , Ali Almuallem , Qi Guo , Stanley H. Chan

Four different applications of spectral proper orthogonal decomposition (SPOD): low-rank reconstruction, denoising, frequency-time analysis, and prewhitening are demonstrated on large-eddy simulation data of a turbulent jet. SPOD-based…

Fluid Dynamics · Physics 2021-09-22 Akhil Nekkanti , Oliver T. Schmidt