Results 31 to 40 of about 240,126 (265)
PERIODIC AND ALMOST-PERIODIC SOLUTIONS OF RECURRENT MULTIPLICATIVE SECOND-ORDER EQUATIONS
Solutions of the recurrent multiplicative equation of a special kind are considered. The values of the parameters of the equation are defined, for which the solutions are periodic, almost periodic or combine properties of a geometric progression and ...
Victor Grigorievich Rudenko +2 more
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Putting the axonal periodic scaffold in order
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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From the Fibonacci Icosagrid to E8 (Part II): The Composite Mapping of the Cores
This 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
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). $$\begin{aligned} \textstyle\begin{cases} \ddot{x}+a(t) x=f(x),\\ x(0)=
Yunhai Wang, Yuanfang Ru
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From the Fibonacci Icosagrid to E8 (Part I): The Fibonacci Icosagrid, an H3 Quasicrystal
This paper introduces a new kind of quasicrystal by Fibonacci-spacing a multigrid of a certain symmetry, like H2, H3, T3, etc. Multigrids of a certain symmetry can be used to generate quasicrystals, but multigrid vertices are not a quasicrystal due to ...
Fang Fang, Klee Irwin
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Periodic Timetabling with Cyclic Order Constraints.
Periodic timetabling for highly utilized railway networks is a demanding challenge. We formulate an infrastructure-aware extension of the Periodic Event Scheduling Problem (PESP) by requiring that not only events, but also activities using the same infrastructure must be separated by a minimum headway time.
Enrico Bortoletto +2 more
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Periodic perturbations of reducible scalar second order functional differential equations
Using a topological approach we investigate the structure of the set of forced oscillations of a class of reducible second order functional retarded differential equations subject to periodic forcing.
Alessandro Calamai +2 more
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Periodic solutions of third order differential equations
In this paper, we study the existence of periodic solutions for the following piecewise third-order differential equation: $$ \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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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]
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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