Results 131 to 140 of about 262,580 (281)
From Stability to Chaos: A Complete Classification of the Damped Klein‐Gordon Dynamics
Mathematical Methods in the Applied Sciences, EarlyView.ABSTRACT We investigate the transition between stability and chaos in the damped Klein‐Gordon equation, a fundamental model for wave propagation and energy dissipation. Using semigroup methods and spectral criteria, we derive explicit thresholds that determine when the system exhibits asymptotic stability and when it displays strong chaotic dynamics ...
Carlos Lizama +2 more
wiley +1 more source
Hölder Regularity of the Solutions of Fredholm Integral Equations on Upper Ahlfors Regular Sets
Mathematical Methods in the Applied Sciences, EarlyView.ABSTRACT We extend to the context of metric measured spaces, with a measure that satisfies upper Ahlfors growth conditions, the validity of (generalized) Hölder continuity results for the solution of a Fredholm integral equation of the second kind. Here we note that upper Ahlfors growth conditions include also cases of nondoubling measures.
Massimo Lanza de Cristoforis +1 more
wiley +1 more source
Subspace-Based Holistic Registration for Low-Resolution Facial Images
EURASIP Journal on Advances in Signal Processing, 2010 Subspace-based holistic registration is introduced as an alternative to landmark-based face registration, which has a poor performance on low-resolution images, as obtained in camera surveillance applications.
Boom BJ, Spreeuwers LJ, Veldhuis RNJ
doaj
Mathematical Methods in the Applied Sciences, EarlyView.ABSTRACT This paper proves the existence of nontrivial solution for two classes of quasilinear systems of the type −ΔΦ1u=Fu(x,u,v)+λRu(x,u,v)inΩ−ΔΦ2v=−Fv(x,u,v)−λRv(x,u,v)inΩu=v=0on∂Ω$$ \left\{\begin{array}{l}\hfill -{\Delta}_{\Phi_1}u={F}_u\left(x,u,v\right)+\lambda {R}_u\left(x,u,v\right)\kern0.1832424242424242em \mathrm{in}\kern0.3em \Omega ...
Lucas da Silva, Marco Souto
wiley +1 more source
Exploring Asymptotic Normality in Multinomial Models
Mathematical Methods in the Applied Sciences, EarlyView.ABSTRACT Among the methods for analyzing categorical outcomes, the multinomial model offers a robust framework for examining the dependence between a multi‐category response variable and a set of explanatory variables. Its flexibility, versatility, and broad applicability across diverse fields make it a valuable tool, as it does not impose strict ...
Célia Nunes +3 more
wiley +1 more source
A Numerical Alternative to MR Thermometry for Safety Validation of Multi‐Channel RF Transmit Coils
Magnetic Resonance in Medicine, EarlyView.ABSTRACT Purpose This study proposes a numerical technique to estimate peak local specific absorption rate (SAR) uncertainty of multi‐channel RF coils during the process of safety validation as an alternative to experimental temperature and electric‐field measurements, and demonstrates its use to enable human studies at 10.5 T.
Alireza Sadeghi‐Tarakameh +14 more
wiley +1 more source
Phase‐Pole‐Free Images and Smooth Coil Sensitivity Maps by Regularized Nonlinear Inversion
Magnetic Resonance in Medicine, EarlyView.ABSTRACT Purpose Phase singularities are a common problem in image reconstruction with auto‐calibrated sensitivities due to an inherent ambiguity of the estimation problem. The purpose of this work is to develop a method for detecting and correcting phase poles in non‐linear inverse (NLINV) reconstruction of MR images and coil sensitivity maps ...
Moritz Blumenthal, Martin Uecker
wiley +1 more source
Maximum-entropy and subspace methods for high-resolution relaxation-diffusion distribution estimation. [PDF]
Imaging Neurosci (Camb)Ning L.
europepmc +1 more source
Magnetic Resonance in Medicine, EarlyView.ABSTRACT Purpose Echo‐planar time‐resolved imaging (EPTI) provides distortion‐ and T2/T2* blurring‐free multi‐echo/multi‐contrast imaging with fast speed, making it an efficient acquisition method for various MRI applications. Here, we aim to achieve water–fat separation for EPTI to improve fat signal removal for brain/body imaging applications. Theory
Zhangxuan Hu +5 more
wiley +1 more source
The detection and correction of silent errors in pipelined Krylov subspace methods. [PDF]
Numer AlgorithmsCarson EC, Hercík J.
europepmc +1 more source