共查询到20条相似文献,搜索用时 46 毫秒
1.
Mei-Yue Jiang 《Journal of Dynamics and Differential Equations》2006,18(4):1043-1067
We consider the periodic solutions of
with f being periodic in t and discontinuous in x. Some results of periodic solutions for continuous nonlinearities are generalized via the critical point theorems for locally Lipschitz functionals. 相似文献
2.
彭奇林 《应用数学和力学(英文版)》2001,22(7):842-845
Uptonow ,thequalitativebehaviorofthesecond_ordernonlineardifferentialequationsandtheirapplicationshavebeendiscussedextensivelyinliterature.WerefertotheRefs .[1 -8] .Conversely ,thediscussionforthequalitativebehaviorofthedelaysystemisless .Inthispaper,westudyt… 相似文献
3.
On the existence of periodic solutions to higher dimensional periodic system with delay 总被引:1,自引:0,他引:1
Consideringthehigherdimensionalperiodicsystemswithdelayoftheformx′(t)=A(t,x(t))x(t)+f(t,x(t-τ)),(1)x′(t)=gradG(x(t))+f(t,x(t-... 相似文献
4.
黄先开 《应用数学和力学(英文版)》1999,20(10):1116-1120
IntroductionIntherecentyears,withalotofapplicationsofneuralnetworkmodels,manyauthors[1~3]areinterestedintheresearchofthestructureandperformanceforthesenetworks.BecauseHopfieldneuralnetworkwellsimulatetheecologicalsystem,manystudiesareconcentratedonth… 相似文献
5.
By using the Z
p
geometrical index theory, some sufficient conditions on the multiplicity results of periodic solutions to the second-order difference equations
are obtained. By two examples, we show that our results are the best possible in the sense that the lower bound of the number of periodic solutions cannot be improved. 相似文献
6.
We consider the Cauchy problem for a strictly hyperbolic, N × N quasilinear system in one-space dimension
where , is a smooth matrix-valued map and the initial data is assumed to have small total variation. We present a front tracking algorithm that generates piecewise constant approximate
solutions converging in to the vanishing viscosity solution of (1), which, by the results in [6], is the unique limit of solutions to the (artificial)
viscous parabolic approximation
as . In the conservative case where A(u) is the Jacobian matrix of some flux function F(u) with values in , the limit of front tracking approximations provides a weak solution of the system of conservation laws u
t
+ F(u)
x
= 0, satisfying the Liu admissibility conditions.
These results are achieved under the only assumption of strict hyperbolicity of the matrices A(u), . In particular, our construction applies to general, strictly hyperbolic systems of conservation laws with characteristic
fields that do not satisfy the standard conditions of genuine nonlinearity or of linear degeneracy in the sense of Lax[17], or in the generalized sense of Liu[23].
Dedicated to Prof. Tai Ping Liu on the occasion of his 60
th
birthday 相似文献
7.
David N. Cheban 《Journal of Dynamics and Differential Equations》2008,20(3):669-697
In the present article we consider a special class of equations
when the function (E is a strictly convex Banach space) is V-monotone with respect to (w.r.t.) , i.e. there exists a continuous non-negative function , which equals to zero only on the diagonal, so that the numerical function α(t):= V(x
1(t), x
2(t)) is non-increasing w.r.t. , where x
1(t) and x
2(t) are two arbitrary solutions of (1) defined on . The main result of this article states that every V-monotone Levitan almost periodic (almost automorphic, Bohr almost periodic) Eq. (1) with bounded solutions admits at least
one Levitan almost periodic (almost automorphic, Bohr almost periodic) solution. In particulary, we obtain some new criterions
of existence of almost recurrent (Levitan almost periodic, almost automophic, recurrent in the sense of Birkgoff) solutions
of forced vectorial Liénard equations.
相似文献
8.
This paper considers the second-order differential difference equation
with the constant delay > 0 and the piecewise constant function
with
Differential equations of this type occur in control systems, e.g., in heating systems and the pupil light reflex, if the controlling function is determined by a constant delay > 0 and the switch recognizes only the positions on [f(>) = a] and off [f(>) = b], depending on a constant threshold value . By the nonsmooth nonlinearity the differential equation allows detailed analysis. It turns out that there is a rich solution structure. For a fixed set of parameters a, b, , , infinitely many different periodic orbits of different minimal periods exist. There may be coexistence of three asymptotically stable periodic orbits (multistability of limit cycles). Stability or instability of orbits can be proven. 相似文献
9.
李永昆 《应用数学和力学(英文版)》2000,21(7):849-854
IntroductionConsiderthenonlinearautonomousdelaydifferentialequationx′(t) ∑mi=1pifi(x(t-τi) ) =0 (1 )andthelinearequationx′(t) ∑mi=1pix(t-τi) =0 ,(2 )where ,pi ∈ (0 ,∞ ) ,τi ∈ [0 ,∞ )andfi ∈C(R ,R)fori =1 ,… ,m .InRef.[1 ] ,thelinearizedoscillationsofEq .(1 )wasstudiedanditwasprovedthatift… 相似文献
10.
In this paper, first a class of fractional differential equations are obtained by using the fractional variational principles.
We find a fractional Lagrangian L(x(t), where
a
c
D
t
α
x(t)) and 0<α<1, such that the following is the corresponding Euler–Lagrange
At last, exact solutions for some Euler–Lagrange equations are presented. In particular, we consider the following equations
where g(t) and f(t) are suitable functions.
D. Baleanu is on leave of absence from Institute of Space Sciences, P.O. BOX MG-23, 76900 Magurele-Bucharest, Romania. e-mail:
baleanu@venus.nipne.ro. 相似文献
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(2) |
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11.
The delay differential equation
with >0 and smooth real functions f, r satisfying f(0)=0, f<0, and r(0)=1 models a system governed by state-dependent delayed negative feedback and instantaneous damping. For a suitable R1 the solutions generate a semiflow F on a compact subset LK of C([–R, 0], ). F leaves invariant the subset S of LK with at most one sign change on all subintervals of [–R, 0] of length one. The induced semiflow on S has a global attractor
\{0} coincides with the set of segments of bounded globally defined slowly oscillating solutions. If
{0}, then
is homeomorphic to the closed unit disk, and the unit circle corresponds to a periodic orbit. 相似文献
12.
IntroductionandProblemintheResearchofToroidThispaperdealswiththeexistenceof2π_periodicsolutionstothenonlinearsystemoffirst_orderdifferentialequationswithadeviatingargument x(t) =Bx(t) F(x(t-τ) ) p(t) ,( 1 )wherex(t)∈R2 , x(t) =ddtx(t) ,τ∈R ,B∈R2×2 ,F :R2 →R2 isboundedandp∈C(… 相似文献
13.
Under certain assumptions on f and g we prove that positive, global and bounded solutions u of the non-autonomous heat equation
in
(N ≥ 3) converge to a steady state.
Dedicated to Prof. Pavol Brunovsky on the occasion of his 70th birthday. 相似文献
14.
By using comparison theorem and constructing suitable Lyapunov functional, we study the following periodic Lotka–Volterra model with M-predators and N-preys by pure-delay type
A set of easily verifiable sufficient conditions are obtained for the existence and global attractivity of a unique positive almost periodic solution of the above model, which improve and generalize some known results. 相似文献
15.
Let E be a Banach space. We prove the instability of the trivial solution of the differential equation
where f: [0, +∞) × E → ℝ is a continuous mapping for which
__________
Translated from Neliniini Kolyvannya, Vol. 8, No. 3, pp. 404–414, July–September, 2005. 相似文献
16.
We investigate the dynamics of the semiflow φ induced on H01(Ω) by the Cauchy problem of the semilinear parabolic equation
on Ω. Here
is a bounded smooth domain, and
has subcritical growth in u and satisfies
. In particular we are interested in the case when f is definite superlinear in u. The set
of attraction of 0 contains a decreasing family of invariant sets
distinguished by the rate of convergence
. We prove that the Wk’s are global submanifolds of
, and we find equilibria in the boundaries
. We also obtain results on nodal and comparison properties of these equilibria. In addition the paper contains a detailed exposition of the semigroup approach for semilinear equations, improving earlier results on stable manifolds and asymptotic behavior near an equilibrium.Supported by DFG Grant BA 1009/15-1. 相似文献
17.
We study the stationary Dirac equation
where M(x) is a matrix potential describing the external field, and R(x, u) stands for an asymptotically quadratic nonlinearity modeling various types of interaction without any periodicity assumption.
For ħ fixed our discussion includes the Coulomb potential as a special case, and for the semiclassical situation (ħ → 0), we handle the scalar fields. We obtain existence and multiplicity results of stationary solutions via critical point
theory. 相似文献
18.
In this paper we begin a study of the differential-delay equation
相似文献
19.
王培光 《应用数学和力学(英文版)》1999,20(6):698-704
IntroductionOwingtotheextensiveapplicationofneutralequations,moreandmorestudieshavebenmadeonthebehaviorofthesolutions[1,2].Fo... 相似文献
20.
Some Results on the <Emphasis Type="BoldItalic">m</Emphasis>-Laplace Equations with Two Growth Terms
We prove the existence of positive radial solutions of the following equation:
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