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This paper addresses the problem of large-scale image retrieval. We propose a two-layer fusion method which takes advantage of global and local cues and ranks database images from coarse to fine (C2F). Departing from the previous methods…

Multimedia · Computer Science 2016-07-05 Gaipeng Kong , Le Dong , Wenpu Dong , Liang Zheng , Qi Tian

We derive boundary conditions and estimates based on the energy and entropy analysis of systems of the nonlinear shallow water equations in two spatial dimensions. It is shown that the energy method provides more details, but is fully…

Analysis of PDEs · Mathematics 2022-04-25 Jan Nordström , Andrew R. Winters

Realistic ab-initio 3D, radiative-hydrodynamical convection simulations of the solar granulation have been applied to FeI and FeII line formation. In contrast to classical analyses based on hydrostatic 1D model atmospheres the procedure…

Astrophysics · Physics 2007-05-23 M. Asplund , AA. Nordlund , R. Trampedach , C. Allende Prieto , R. F. Stein

Despite the cheap availability of computing resources enabling faster Monte Carlo simulations, the potential benefits of particle filtering in revealing accurate statistical information on the imprecisely known model parameters or modeling…

Methodology · Statistics 2014-02-07 Saikat Sarkar , Debasish Roy

Large-eddy simulations (LES) are widely-used for computing high Reynolds number turbulent flows. Spatial filtering theory for LES is not without its shortcomings, including how to define filtering for wall-bounded flows, commutation errors…

Fluid Dynamics · Physics 2022-02-02 Perry L. Johnson

Numerical simulations of atmospheric circulation models are limited by their finite spatial resolution, and so large eddy simulation (LES) is the preferred approach to study these models. In LES a low-pass filter is applied to the flow…

Fluid Dynamics · Physics 2016-04-27 Leila N. Azadani , Anne E. Staples

We present a proof-of-principle implementation of the first fully covariant filtering scheme applied to relativistic fluid turbulence. The filtering is performed with respect to special observers, identified dynamically as moving with the…

High Energy Astrophysical Phenomena · Physics 2025-01-07 T. Celora , M. J. Hatton , I. Hawke , N. Andersson

We quantify the Fisher information content of the cosmic shear survey two-point function as a function of noise and resolution. The two point information of dark matter saturates at the trans-linear scale. We investigate the impact of…

Cosmology and Nongalactic Astrophysics · Physics 2009-05-06 Olivier Doré , Tingting Lu , Ue-Li Pen

We derive and analyze in the framework of the mild-slope approximation a new double-layer Boussinesq-type model which is linearly and nonlinearly accurate up to deep water. Assuming the flow to be irrotational, we formulate the problem in…

Atmospheric and Oceanic Physics · Physics 2009-07-01 Florent Chazel , Michel Benoit , Alexandre Ern , Serge Piperno

This paper puts forth a new large eddy simulation closure modeling strategy for two-dimensional turbulent geophysical flows. This closure modeling approach utilizes approximate deconvolution, which is based solely on mathematical…

Atmospheric and Oceanic Physics · Physics 2013-10-08 Omer San , Anne E. Staples , Zhu Wang , Traian Iliescu

Extensive studies have investigated the transition mechanism of boundary layers initiated by a single primary instability. In a real-world scenario, however, multiple primary instabilities of different physical nature would coexist and…

Fluid Dynamics · Physics 2026-03-18 Xiao-Bai Li , Yifeng Chen , Chihyung Wen , Peixu Guo

Nonlinear regression is a useful statistical tool, relating observed data and a nonlinear function of unknown parameters. When the parameter-dependent nonlinear function is computationally intensive, a straightforward regression analysis by…

Applications · Statistics 2009-01-26 Dorin Drignei , Chris E. Forest , Doug Nychka

General equations describing shear displacements in incompressible hyperelastic materials, holding for an arbitrary form of strain energy density function, are presented and applied to the description of nonlinear Love-type waves…

Exactly Solvable and Integrable Systems · Physics 2026-03-20 Shawn Samuel Carl McAdam , Samuel Opoku Agyemang , Alexei Cheviakov

This work develops a nonlinear multigrid method for diffusion problems discretized by cell-centered finite volume methods on general unstructured grids. The multigrid hierarchy is constructed algebraically using aggregation of degrees of…

Numerical Analysis · Mathematics 2020-10-29 Chak Shing Lee , François Hamon , Nicola Castelletto , Panayot S. Vassilevski , Joshua White

We investigate turbulence generated by cosmological structure formation by means of large eddy simulations using adaptive mesh refinement. In contrast to the widely used implicit large eddy simulations, which resolve a limited range of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 W. Schmidt , A. S. Almgren , H. Braun , J. F. Engels , J. C. Niemeyer , J. Schulz , R. R. Mekuria , A. J. Aspden , J. B. Bell

A system using a non-linear multi-swept sine wave system is described which employs a multi-channel, multi-swept orthogonal waves, to separate channels and make multiple, simultaneous online/offline CO2 measurements. An analytic expression…

Atmospheric and Oceanic Physics · Physics 2013-04-30 Joel F. Campbell

Deep neural networks have achieved remarkable breakthroughs by leveraging multiple layers of data processing to extract hidden representations, albeit at the cost of large electronic computing power. To enhance energy efficiency and speed,…

Gaussian mixture filters for nonlinear systems usually rely on severe approximations when calculating mixtures in the prediction and filtering step. Thus, offline approximations of noise densities by Gaussian mixture densities to reduce the…

Systems and Control · Electrical Eng. & Systems 2025-06-02 Ondŕej Straka , Uwe D. Hanebeck

Gaussian mixtures are a common density representation in nonlinear, non-Gaussian Bayesian state estimation. Selecting an appropriate number of Gaussian components, however, is difficult as one has to trade of computational complexity…

Systems and Control · Computer Science 2012-04-02 Marco F. Huber

The linear wave and geostrophic (vortex) solutions are shown to be a complete basis for physical variables $(u,v,w,\rho)$ in a rotating non-hydrostatic Boussinesq model with arbitrary stratification. As a consequence, the fluid can be…

Fluid Dynamics · Physics 2021-02-16 Jeffrey J. Early , M. Pascale Lelong , Miles A. Sundermeyer