Results 71 to 80 of about 6,274 (271)

Homoclinic Solutions and Chaos in Ordinary Differential Equations with Singular Perturbations [PDF]

Transactions of the American Mathematical Society, 1998
Ordinary differential equations are considered which contain a singular perturbation. It is assumed that when the perturbation parameter is zero, the equation has a hyperbolic equilibrium and homoclinic solution. No restriction is placed on the dimension of the phase space or on the dimension of intersection of the stable and unstable manifolds.
openaire   +1 more source

Effects of Add‐On Icosapent Ethyl With Standard Treatment on Functional Outcomes and Inflammatory Biomarkers in Acute Ischemic Stroke: A Blinded Randomized Controlled Trial

Annals of Clinical and Translational Neurology, EarlyView.
ABSTRACT Background Ischemic stroke, a major cause of mortality and long‐term disability, results from the abrupt cessation of cerebral blood flow due to vascular occlusion or rupture. Icosapent Ethyl (EPA‐EE), approved for hypertriglyceridemia, has anti‐inflammatory and antithrombotic properties that may lessen ischemic damage.
Mitra Mahmoudi Meymand, Seyed Hossein Aghamiri, Saeed Mohmammad Soleymani, Shadiyeh Bararpoor Poshkohi, Samaneh Masoudi, Hadi Esmaily   +5 more
wiley   +1 more source

Nonlinear Perturbations and Weak Shock Waves in Isentropic Atmospheres

The Astrophysical Journal
Acoustic perturbations to stellar envelopes can lead to the formation of weak shock waves via nonlinear wave steepening. Close to the stellar surface, the weak shock wave increases in strength and can potentially lead to the expulsion of part of the ...
Tamar Faran, Christopher D. Matzner, Eliot Quataert   +2 more
doaj   +1 more source

Algebraic analysis of singular perturbation theory

, 2005
The topic of this book is the study of singular perturbations of ordinary differential equations, i.e., perturbations that represent solutions as asymptotic series rather than as analytic functions in a perturbation parameter.
Takei, Yoshitsugu, Kawai, Takahiro
core  

Differential Item Functioning on the Patient Health Questionnaire 8 by Disease Subtype, Language, Sex, and Age Among People With Systemic Sclerosis: A Scleroderma Patient‐Centered Intervention Network Cohort Study

Arthritis Care &Research, EarlyView.
Objective Somatic items used in depression assessments can potentially overlap with symptoms related to physical illness, including systemic sclerosis (SSc). No studies have looked at whether somatic depression items may be influenced by diffuse versus limited SSc disease subtypes, which are associated with varying degrees of symptom presentation.
Sophie Hu, Marie‐Eve Carrier, Marie‐Claude Geoffroy, Meira Golberg, Linda Kwakkenbos, Susan J. Bartlett, Catherine Fortuné, Amy Gietzen, Karen Gottesman, Geneviève Guillot, Laura K. Hummers, Amanda Lawrie‐Jones, Vanessa L. Malcarne, Michelle Richard, Maureen Sauvé, Luc Mouthon, Andrea Benedetti, Brett D. Thombs, on behalf of the SPIN Investigators, Claire E. Adams, Marie Hudson, Maureen D. Mayes, James Stempel, Robyn K. Wojeck, Christian Agard, Laurent Alric, Marc André, Floryan Beaslay, Elana J. Bernstein, Sabine Berthier, Lyne Bissonnette, Sophie Blaise, Eva Bories, Alessandra Bruns, Carlotta Cacciatore, Patricia Carreira, Marion Casadevall, Benjamin Chaigne, Lorinda Chung, Benjamin Crichi, Thylbert Deltombe, Christopher P. Denton, Tannvir Desroche, Robyn Domsic, James V. Dunne, Bertrand Dunogue, Regina Fare, Dominique Farge‐Bancel, Paul R. Fortin, Tracy Frech, Loraine Gauzère, Anne Gerber, Jessica K. Gordon, Brigitte Granel‐Rey, Aurélien Guffroy, Geneviève Gyger, Eric Hachulla, Daphna Harel, Monique Hinchcliff, Sabrina Hoa, Michael Hugues, Alena Ikic, Sindhu R. Johnson, Nader Khalidi, Kimberly S. Lakin, Marc Lambert, Maggie Larche, David Launay, Yvonne C. Lee, Paul Legendre, Catarina Leite, Hélène Maillard, Nancy Maltez, Joanne Manning, Isabelle Marie, Maria Martin Lopez, Thierry Martin, Ariel Masetto, Arsène Mekinian, Sheila Melchor Díaz, Morgane Mourguet, Christelle Nguyen, Karen Nielsen, Mandana Nikpour, Louis Olagne, Vincent Poindron, Janet Pope, Susanna Proudman, Grégory Pugnet, Loïc Raffray, François Rannou, Alexis Régent, Frederic Renou, Sébastien Rivière, David Robinson, Esther Rodríguez Almazar, Tatiana Sofia Rodríguez‐Reyna, Sophie Roux, Perrine Smets, Vincent Sobanski, Robert F. Spiera, Virginia Steen, Evelyn Sutton, Carter Thorne, Damien Vagner, John Varga, Pearce Wilcox, Vanessa Cook, Cassidy Dal Santo, Monica D'Onofrio, Elsa‐Lynn Nassar   +110 more
wiley   +1 more source

Perturbations of nonlinear systems of ordinary differential equations

Journal of Mathematical Analysis and Applications, 1984
Along with the n dimensional system (1) \(y'=f(t,y)\) the perturbed system (2) \(x'=f(t,x)+g(t,x)\) is considered. Certain refined assumptions are made about estimates of the fundamental matrix solution of the variational system with respect to a solution of system (1), and about g. (The function g need not be ''small'', it may be sublinear or linear.)
openaire   +2 more sources

Adaptive Observer for Coupled Wave PDE and Infinite ODE With Sampled Data and Unknown Input: Application to Brain Hemodynamics Estimation

International Journal of Adaptive Control and Signal Processing, EarlyView.
This article proposes a convergent adaptive observer for a damped wave PDE and an infinite‐dimensional ODE coupled in cascade using sampled‐in‐space ODE state measurements. The proposed observer estimates the distributed states of the PDE and ODE along with unknown PDE parameters and spatial input.
Zehor Belkhatir, Sarah Mechhoud, Taous‐Meriem Laleg‐Kirati   +2 more
wiley   +1 more source

Sound wave propagation problems new perturbation methodology

Archives of Acoustics, 2014
The aim of the paper is to present applications of the new algebraic system theory in acoustic problems. Elements of new types of perturbed ordinary and partial differential equations are discussed.
Jerzy Skrzypczyk, A. Winkler-Skalna
doaj  

Spacetime perspective of gravitational lensing in perturbed cosmologies

Scientific Reports
We develop the spacetime approach to gravitational lensing by spherically symmetric perturbations of flat, cosmological constant-dominated Friedman-Robertson-Walker metrics.
Thomas P. Kling, Sophia MacQueen Pooler
doaj   +1 more source

Observer‐Based Adaptive Event‐Triggered Tracking Control for Fuzzy TS Systems With Premise Mismatch

International Journal of Adaptive Control and Signal Processing, EarlyView.
This paper presents an adaptive logistic event‐triggered observer‐based tracking controller for Takagi‐Sugeno fuzzy systems under constrained inputs and network delays. Leveraging a hybrid LMI and Secretary Bird Optimization approach, this strategy significantly minimizes communication overhead and computational burden while ensuring optimal reference ...
Oussama Djadane, Salama Makni, Mourad Kchaou, Ahmed El Hajjaji   +3 more
wiley   +1 more source