Results 61 to 70 of about 371,472 (295)
Limit cycles for fourth-order autonomous differential equations
Electronic Journal of Differential Equations, 2012 We provide sufficient conditions for the existence of periodic solutions of the fourth-order differential equation $$ ddddot x -(lambda+mu) dddot x +(1+lambda mu)ddot x -(lambda+mu)dot x+lambda mu x = varepsilon F(x, dot x, ddot x, dddot x ...
Jaume Llibre, Amar Makhlouf
doaj
Oscillation of Fourth-Order Functional Differential Equations with Distributed Delay
Axioms, 2019 In this paper, the authors obtain some new sufficient conditions for the oscillation of all solutions of the fourth order delay differential equations.
Clemente Cesarano, Omar Bazighifan
doaj +1 more source
Arthritis Care &Research, EarlyView.Objective Foot orthoses are thought to improve pain by potentially modifying internal mechanical forces. To test this, we explored whether foot orthoses can modify patterns of bone marrow lesions (BMLs) in people with midfoot pain. Methods Forty‐two people were recruited with midfoot pain, and magnetic resonance imaging–confirmed midfoot BMLs ...
Jill Halstead +4 more
wiley +1 more source
On the asymptotic behavior of fourth-order functional differential equations
Advances in Difference Equations, 2017 The aim of this work is to study asymptotic properties of a class of fourth-order delay differential equations. Our results in this paper not only generalize some previous results, but also improve the earlier ones.
Osama Moaaz +2 more
doaj +1 more source
Some spectral properties of fourth order differential operator equation [PDF]
Operators and Matrices, 2018 Consider in the separable Hilbert space \(H\) the eigenvalue problem \[ \begin{gathered} y^{(4)}(x)+ Ay(x)+ q(x) y(x)= \lambda y(x),\qquad ...
Aslanova, Nigar M. +2 more
openaire +1 more source
Arthritis Care &Research, EarlyView.Objective Relapsing polychondritis (RP) is a rare disease defined by recurrent cartilaginous inflammation. Anti–collagen II (Col2) antibodies have been proposed as a diagnostic biomarker for RP, but their performance characteristics are not well defined.
Karyssa Stonick +6 more
wiley +1 more source
Multiscaling in passive scalar advection as stochastic shape dynamics
, 1997 The Kraichnan rapid advection model is recast as the stochastic dynamics of tracer trajectories. This framework replaces the random fields with a small set of stochastic ordinary differential equations.
B. Derrida +11 more
core +1 more source
Retractions in Rheumatology: Trends, Causes, and Implications for Research Integrity
Arthritis Care &Research, EarlyView.Objective We aimed to describe the trends and main reasons for study retraction in rheumatology literature. Methods We reviewed the Retraction Watch database to identify retracted articles in rheumatology. We recorded the main study characteristics, authors’ countries, reasons for retraction, time from publication to retraction, and trends over time ...
Anna Maria Vettori, Michele Iudici
wiley +1 more source
Correction to: “Periodic solutions of fourth-order differential equations” [PDF]
Proceedings of the American Mathematical Society, 1967 1. M. Abramowitz and I. A. Stegun, Handbook of mathematical functions with formulas, graphs, and mathematical tables, National Bureau of Standards, Applied Mathematics Series 55, 3rd printing, with corrections, March, 1965. 2. P. F. Hsieh and Y. Sibuya, On the asymptotic integration of second order linear ordinary differential equations with polynomial
openaire +2 more sources
A Q‐Learning Algorithm to Solve the Two‐Player Zero‐Sum Game Problem for Nonlinear Systems
International Journal of Adaptive Control and Signal Processing, Volume 39, Issue 3, Page 566-581, March 2025.A Q‐learning algorithm to solve the two‐player zero‐sum game problem for nonlinear systems. ABSTRACT This paper deals with the two‐player zero‐sum game problem, which is a bounded L2$$ {L}_2 $$‐gain robust control problem. Finding an analytical solution to the complex Hamilton‐Jacobi‐Issacs (HJI) equation is a challenging task.
Afreen Islam +2 more
wiley +1 more source