首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 554 毫秒
1.
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   

2.
Stability of a class of neural network models with delay   总被引:6,自引:0,他引:6  
IntroductionRecently,theoreticalandapliedstudiesofneuralnetworkmodelhavebenthenewfocusofstudiesintheworld.Itiswel_knownthatqu...  相似文献   

3.
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   

4.
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   

5.
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
(1)
At last, exact solutions for some Euler–Lagrange equations are presented. In particular, we consider the following equations
(2)
(3)
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   

6.
Let X be a uniformly smooth real Banach space. Let T:X → X be continuos and strongly accretive operator. For a given f ε X, define S: X → X by Sx =f−Tx+x, for all x ε X. Let {an} n=0 , {βn} n=0 be two real sequences in (0, 1) satisfying:
((i))
;
((ii))
Assume that {un} n=0 and {υn} n=0 are two sequences in X satisfying ‖un‖ = 0(αn) and ‖υn‖ → 0 as n → ∞. For arbitrary x0 ε X, the iteration sequence {xn} is defined by
(1)
Moreover, suppose that {Sxn} and {Syn} are bounded, then {xn} converges strongly to the unique fixed point of S.  相似文献   

7.
1IntroductionandPreliminariesLetXbearealBanachspacewithnormIJ'11andadualX'.ThenormalizeddualitymappingJ:X~ZxisdefinedbyJx={x'eX*I(x,x')=11x112=11x if'},where',')denotesthegeneralizeddualitypairing.Itiswell-knownthatifX isstrictlyconvex,Jissingle-valuedandJ(tx)=tjxforallt201xeX.IfX*isuniformlyconvex,thenJisuniformlycontinuousonanyboundedsubsetSofX(of.Browde,fljandBarbuL2]).AnoperatorTwithdomainD(T)andrangeR(T)inXissaidtobeaccretiveifforeveryx,y6D(T),thereexistsajeJ(x--y)suchthat(T…  相似文献   

8.
On nonlinear hyperbolic equation in unbounded domain   总被引:2,自引:0,他引:2  
The following nonlinear hyperbolic equation is discussed in this paper: where The model comes from the transverse deflection equation of an extensible beam. We prove that there exists a unique local solution of the above equation as M depends on x.  相似文献   

9.
In this paper, the solution of a 2-D weak singular integral equation of the first kind
  相似文献   

10.
I.IntroductionItiswell-knobal.nthatKorteweg-deVriesequationisacanonicalmodeltodescribethebalanceofthenonlineareffectandthedispersiveeffectofaphysicalsystem.Thisequationpossessestheso-called'soliton"solution,whichhasbeenfoundnumericallybyZabuskyandKruskall'].Ho-c'Jlever,sometimesthebalanceofnonlinearityanddispersionofasystemmayleadtoa,integroditTerentialequationinsteadofadifferentialequation.Forinstance,inthestudyofvortexbreakdownofanunboundedrotatingfluidLeibovich12]derivedfollowingnonline…  相似文献   

11.
1ProblemsandMainResultsInthispaper,westudythenonlinearvibrationsofinfiniterodswithviscoelasticity.Theconstitutionlawoftherods...  相似文献   

12.
IntroductionIntherecentyears,withalotofapplicationsofneuralnetworkmodels,manyauthors[1~3]areinterestedintheresearchofthestructureandperformanceforthesenetworks.BecauseHopfieldneuralnetworkwellsimulatetheecologicalsystem,manystudiesareconcentratedonth…  相似文献   

13.
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   

14.
We prove the following statement: Theorem 1. Let E and be an arbitrary infinite-dimensional Banach space and a continuous mapping, respectively. Then, for every and > 0, there exists a continuous mapping such that
and the Cauchy problem
does not have a solution for every > 0.  相似文献   

15.
Periodicity and strict oscillation for generalized lyness equations   总被引:1,自引:0,他引:1  
IntroductionConsiderthefollowingdelaydifferenceequationxn 1=xn(a bxn)xn- 1,  n=0 ,1 ,2 ,… ,(1 )wherea ,b∈ [0 ,∞ )witha b>0 (2 )andwheretheinitialvaluesx- 1andx0 arearbitrarypositivenumbers.Eq .(1 )isregardedasageneralizedLynessequationbyG .Ladasin [1 ] .Obviously ,undercondition (2 ) ,…  相似文献   

16.
IntroductionAtpresent,thereareonlyafewpapers[1~3]havingbenpublishedontheglobalexistenceofperiodicsolutionsforneutraldelaypopu...  相似文献   

17.
18.
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   

19.
Existence of a Solution “in the Large” for Ocean Dynamics Equations   总被引:1,自引:0,他引:1  
For the system of equations describing the large-scale ocean dynamics, an existence and uniqueness theorem is proved “in the large”. This system is obtained from the 3D Navier–Stokes equations by changing the equation for the vertical velocity component u 3 under the assumption of smallness of a domain in z-direction, and a nonlinear equation for the density function ρ is added. More precisely, it is proved that for an arbitrary time interval [0, T], any viscosity coefficients and any initial conditions
a weak solution exists and is unique and and the norms are continuous in t. The work was carried out under partial support of Russian Foundation for Basic Research (project 05-01-00864).  相似文献   

20.
We study the limit of the hyperbolic–parabolic approximation
The function is defined in such a way as to guarantee that the initial boundary value problem is well posed even if is not invertible. The data and are constant. When is invertible, the previous problem takes the simpler form
Again, the data and are constant. The conservative case is included in the previous formulations. Convergence of the , smallness of the total variation and other technical hypotheses are assumed, and a complete characterization of the limit is provided. The most interesting points are the following: First, the boundary characteristic case is considered, that is, one eigenvalue of can be 0. Second, as pointed out before, we take into account the possibility that is not invertible. To deal with this case, we take as hypotheses conditions that were introduced by Kawashima and Shizuta relying on physically meaningful examples. We also introduce a new condition of block linear degeneracy. We prove that, if this condition is not satisfied, then pathological behaviors may occur.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号