Results 41 to 50 of about 9,489,153 (244)
Putting the axonal periodic scaffold in order
Current Opinion in Neurobiology, 2021 Neurons rely on a unique organization of their cytoskeleton to build, maintain and transform their extraordinarily intricate shapes. After decades of research on the neuronal cytoskeleton, it is exciting that novel assemblies are still discovered thanks to progress in cellular imaging methods. Indeed, super-resolution microscopy has revealed that axons
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Periodic solutions of second-order nonautonomous dynamical systems
Boundary Value Problems, 2006 We study the existence of periodic solutions for second-order nonautonomous dynamical systems. We give four sets of hypotheses which guarantee the existence of solutions.
Schechter Martin
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From the Fibonacci Icosagrid to E8 (Part II): The Composite Mapping of the Cores
CrystalsThis paper is part of a series that describes the Fibonacci icosagrid quasicrystal (FIG) and its relation to the E8 root lattice. The FIG was originally constructed to represent the intersection points of an icosahedrally symmetric collection of planar ...
Richard Clawson, Fang Fang, Klee Irwin
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On positive periodic solutions of second order singular equations
Boundary Value Problems, 2018 Using the fixed point theorem, we study the existence and multiplicity of positive periodic solutions for the second order differential equations {x¨+a(t)x=f(x),x(0)=x(T),x˙(0)=x˙(T). $$\begin{aligned} \textstyle\begin{cases} \ddot{x}+a(t) x=f(x),\\ x(0)=
Yunhai Wang, Yuanfang Ru
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From the Fibonacci Icosagrid to E8 (Part I): The Fibonacci Icosagrid, an H3 Quasicrystal
CrystalsThis paper introduces a new kind of quasicrystal by Fibonacci-spacing a multigrid of a certain symmetry, like H2, H3, T3, etc. Multigrids of a certain symmetry can be used to generate quasicrystals, but multigrid vertices are not a quasicrystal due to ...
Fang Fang, Klee Irwin
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Periodic perturbations of reducible scalar second order functional differential equations
Electronic Journal of Qualitative Theory of Differential Equations, 2023 Using a topological approach we investigate the structure of the set of forced oscillations of a class of reducible second order functional retarded differential equations subject to periodic forcing.
Alessandro Calamai +2 more
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Periodic solutions of third order differential equations
Journal of Innovative Applied Mathematics and Computational SciencesIn this paper, we study the existence of periodic solutions for the following piecewise third-order differential equation: $$ \dddot{x}+\dot{x}-\varepsilon\sum\limits_{i=1}^{2}c_i|x|^i=0, $$ with $\varepsilon$ a real parameter sufficiently small, $c_1$
Nabil Rezaiki, Amel Boulfoul
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Abstract and Applied Analysis, 2012 In this paper, two classes of first-order neutral functional differential equations with periodic delays are considered. Some results on the existence of positive periodic solutions for the equations are obtained by using the Krasnoselskii fixed point ...
Zeqing Liu +3 more
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Periodic unique beta-expansions: the Sharkovskiĭ ordering [PDF]
Ergodic Theory and Dynamical Systems, 2009 AbstractLetβ∈(1,2). Eachx∈[0,1/(β−1)] can be represented in the formwhere εk∈{0,1} for allk(aβ-expansion ofx). If$\beta >{(1+\sqrt 5)}/{2}$, then, as is well known, there always existx∈(0,1/(β−1)) which have a uniqueβ-expansion. We study (purely) periodic uniqueβ-expansions and show that for eachn≥2 there exists$\beta _n\in [{(1+\sqrt 5)}/{2},2)$
Allouche, Jean Paul +2 more
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An overview of recent developments in computational methods for periodic systems [PDF]
, 2007 : At the First IFAC Workshop on Periodic Systems (Como, Italy, 2001), a state of the art survey of computational methods for periodic systems has been presented (Varga and Van Dooren, 2001).
Andras Varga, Varga, Andreas
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