Results 61 to 70 of about 4,377 (209)

Numerical modelling investigation of finite‐amplitude subaqueous dune saturation

Earth Surface Processes and Landforms, Volume 50, Issue 4, Page 1-19, 30 March 2025.
Our work demonstrates how finite amplitude dunes in limited depth flows reach a saturation state, preventing their growth. Saturation occurs when the intensity of the turbulent mixing reaches critical thresholds, enhanced by the confinement, reducing inertia and stirring large quantities of suspended sediment downstream of dune crests.
Arnaud Doré, Giovanni Coco
wiley   +1 more source

Improvements on the Leighton‐type oscillation criteria for impulsive differential equations and extension to non‐canonical case

Mathematical Methods in the Applied Sciences, Volume 48, Issue 4, Page 5315-5324, 15 March 2025.
We investigate the oscillatory behavior of solutions of second‐order linear differential equations with impulses. These equations can be categorized into two types: canonical and non‐canonical. This study examines the canonical and non‐canonical impulsive differential equations in connection with the famous Leighton‐type oscillation theorem.
A. Zafer, S. Doğru Akgöl
wiley   +1 more source

An Eulerian formulation for the computational modeling of phase‐contrast MRI

Magnetic Resonance in Medicine, Volume 93, Issue 2, Page 828-841, February 2025.
Abstract Purpose Computational simulation of phase‐contrast MRI (PC‐MRI) is an attractive way to physically interpret properties and errors in MRI‐reconstructed flow velocity fields. Recent studies have developed PC‐MRI simulators that solve the Bloch equation, with the magnetization transport being modeled using a Lagrangian approach.
Tomohiro Otani, Tetsuro Sekine, Yu Sato, Ellen Cavalcante Alves, Shigeo Wada   +4 more
wiley   +1 more source

Existence of nonoscillatory solutions tending to zero of third-order neutral dynamic equations on time scales

Advances in Difference Equations, 2020
We study the existence of nonoscillatory solutions tending to zero of a class of third-order nonlinear neutral dynamic equations on time scales by employing Krasnoselskii’s fixed point theorem. Two examples are given to illustrate the significance of the
Yang-Cong Qiu, Irena Jadlovská, Kuo-Shou Chiu, Tongxing Li   +3 more
doaj   +1 more source

Renormalization study of two-dimensional convergent solutions of the porous medium equation

, 1999
In the focusing problem we study a solution of the porous medium equation $u_t=\Delta (u^m)$ whose initial distribution is positive in the exterior of a closed non-circular two dimensional region, and zero inside.
Angenent, Angenent, Aronson, Barenblatt, Chen, D.G. Aronson, Diez, Diez, Gratton, Hupper, Osher, Osher, S.B. Angenent, S.I. Betelú, Shu   +14 more
core   +4 more sources

A Generalised Power Synchronisation Loop Design for Performance Enhancement of Grid‐Forming Converter

IET Smart Grid, Volume 8, Issue 1, January/December 2025.
A generalised power synchronisation loop (GPSL) is proposed to enable the adjustment of the inertia, the damping and stiffness characteristics of the GFM converter simultaneously. The flexibility and stability of GPSL in a single GFM converter system and multiple GFM converter system is analysed.
Yifeng Li, Wei Pei, Jiawang Xiong, Wei Deng   +3 more
wiley   +1 more source

Existence of nonoscillatory solutions for higher order nonlinear mixed neutral differential equations

Mathematical Modelling and Control
In this paper, the existence of nonoscillatory solutions for a class of higher-order nonlinear differential equations is investigated. Notably, the equations are of mixed neutral type with a forcing term, which distinguished the equations in this paper ...
Hui Li, Nana Jin, Yu Zhang
doaj   +1 more source

Relative Oscillation Theory, Weighted Zeros of the Wronskian, and the Spectral Shift Function

, 2008
We develop an analog of classical oscillation theory for Sturm-Liouville operators which, rather than measuring the spectrum of one single operator, measures the difference between the spectra of two different operators. This is done by replacing zeros
A. Kneser, A. Zettl, B. Simon, B. Simon, D.R. Yafaev, F. Gesztesy, F. Gesztesy, F. Gesztesy, F.S. Rofe-Beketov, F.S. Rofe-Beketov, F.S. Rofe-Beketov, F.S. Rofe-Beketov, G. Stolz, G. Teschl, G. Teschl, G. Teschl, G. Teschl, Gerald Teschl, H. Krüger, Helge Krüger, I. Gohberg, J. Weidmann, J. Weidmann, J. Weidmann, J.C.F. Sturm, K.M. Schmidt, K.M. Schmidt, K.M. Schmidt, M. Reed, M.G. Krein, M.S.P. Eastham, M.Sh. Birman, P. Hartman, P. Hartman, P. Hartman, S.V. Khryashchev, T. Kato, W. Leighton, W. Walter   +38 more
core   +8 more sources

NONOSCILLATORY SOLUTIONS OF DELAY DIFFERENCE EQUATIONS WITH OSCILLATING COEFFICIENTS

Demonstratio Mathematica, 2003
Using the analogy with differential equations with deviated argument the authors study non-oscillatory solutions of the scalar equation \[ \Delta y_k = P^o_ky_k + \sum_1^nP^i_ky_{k-K^i_k} \] with bounded coefficients satisfying an oscillation condition.
Bolat, Yaşar, Akin, Ömer
openaire   +2 more sources

A Review on High‐Speed Electromagnetic Flow Control and Applications Considering Numerical Methods, Simulations, and Experimental Research Data

International Journal of Aerospace Engineering, Volume 2025, Issue 1, 2025.
Background: Electromagnetic flow control is crucial in hypersonic gas dynamics, with key aspects of boundary layer electromagnetic flow control reviewed, focusing on numerical methods, simulations, and experimental research. Numerical Methods: Challenges such as numerical stiffness and instability arise from the coupling of electromagnetic fields with ...
Yang Du, Jun Liu, Hao Chen
wiley   +1 more source