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

2.
We consider the initial boundary-value problem for a system of quasilinear partial functional differential equations of the first order
$ {*{20}{c}} {{\partial_t}{z_i}\left( {t,x} \right) + \sum\limits_{j = 1}^n {{\rho_{ij}}\left( {t,x,V\left( {z;t,x} \right)} \right){\partial_{{x_j}}}{z_i}\left( {t,x} \right) = {G_i}\left( {t,x,V\left( {z;t,x} \right)} \right),} } \hfill & {1 \leq i \leq m,} \hfill \\ $ \begin{array}{*{20}{c}} {{\partial_t}{z_i}\left( {t,x} \right) + \sum\limits_{j = 1}^n {{\rho_{ij}}\left( {t,x,V\left( {z;t,x} \right)} \right){\partial_{{x_j}}}{z_i}\left( {t,x} \right) = {G_i}\left( {t,x,V\left( {z;t,x} \right)} \right),} } \hfill & {1 \leq i \leq m,} \hfill \\ \end{array}  相似文献   

3.
1ProblemsandMainResultsInthispaper,westudythenonlinearvibrationsofinfiniterodswithviscoelasticity.Theconstitutionlawoftherods...  相似文献   

4.
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   

5.
Ref. [1] discussed the existence of positive solutions of quasilinear two-point boundary problems: but it restricts O相似文献   

6.
In recent years,there is a wide interest in Sarkovskii’s theorem and related study.According to Sarkovskii’s theorem,if the continuous self-map f of the closed interval has a3-periodic orbit,then f must has an n-periodic orbit for any positive integer n.But f can nothave all n-periodic orbits for some n.Example.LetEvidently f has only one kind of3-periodic orbit in the two kinds of3-periodic orbits,whichexplains that it isn’t far enough to uncover the relation between periodic orbits by theinformation which Sarkovskii’s theorem has offered.In this paper,we raise the concept oftype of periodic orbits,and give a feasible algorithm which decldes the relation ofimplication between the two kinds of periodic orbits.  相似文献   

7.
IntroductionOwingtotheextensiveapplicationofneutralequations,moreandmorestudieshavebenmadeonthebehaviorofthesolutions[1,2].Fo...  相似文献   

8.
IntroductionIntherecentyears,withalotofapplicationsofneuralnetworkmodels,manyauthors[1~3]areinterestedintheresearchofthestructureandperformanceforthesenetworks.BecauseHopfieldneuralnetworkwellsimulatetheecologicalsystem,manystudiesareconcentratedonth…  相似文献   

9.
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   

10.
D. Woiki  P. Roth 《Shock Waves》1994,4(2):95-99
The thermal decomposition of CS2 highly diluted in Ar was studied behind reflected shock waves by monitoring time-dependent absorption profiles of S(3P) and S(1D) using atomic resonance absorption spectroscopy (ARAS). The rate coefficient of the reaction:
  相似文献   

11.
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   

12.
Let u, p be a weak solution of the stationary Navier-Stokes equations in a bounded domain N, 5N . If u, p satisfy the additional conditions
  相似文献   

13.
I.IntroductionItiswell-knobal.nthatKorteweg-deVriesequationisacanonicalmodeltodescribethebalanceofthenonlineareffectandthedispersiveeffectofaphysicalsystem.Thisequationpossessestheso-called'soliton"solution,whichhasbeenfoundnumericallybyZabuskyandKruskall'].Ho-c'Jlever,sometimesthebalanceofnonlinearityanddispersionofasystemmayleadtoa,integroditTerentialequationinsteadofadifferentialequation.Forinstance,inthestudyofvortexbreakdownofanunboundedrotatingfluidLeibovich12]derivedfollowingnonline…  相似文献   

14.
Introductionp_Laplaceequationsariseinavarietyofinterestingapplications,theyappearasmodelsofgasdiffusionthroughporousmedia,alsointhetheoryofthermalself_ignitionofachemicallyactivemixtureofgases(see [1 ]anditsreferences) ,recently ,WANGJun_yu (Ref.[1 ] )studiedth…  相似文献   

15.
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   

16.
We prove that the solution semigroup $$S_t \left[ {u_0 ,v_0 } \right] = \left[ {u(t),u_t (t)} \right]$$ generated by the evolutionary problem $$\left\{ P \right\}\left\{ \begin{gathered} u_{tt} + g(u_t ) + Lu + f(u) = 0, t \geqslant 0 \hfill \\ u(0) = u_0 , u_t (0) = \upsilon _0 \hfill \\ \end{gathered} \right.$$ possesses a global attractorA in the energy spaceE o=V×L 2(Ω). Moreover,A is contained in a finite-dimensional inertial setA attracting bounded subsets ofE 1=D(LV exponentially with growing time.  相似文献   

17.
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   

18.
Asymptotic solutions of linear systems of ordinary differential equations are employed to discuss the relationship of the solution of a certain “complete” boundary problem.
$$\begin{gathered} \left\{ \begin{gathered} {\text{ }}\frac{{d{\text{ }}x_1 }}{{d{\text{ }}t}} = A_{11} (t,\varepsilon ){\text{ }}x_1 (t,\varepsilon ){\text{ }} + \cdots + A_{1p} (t,\varepsilon ){\text{ }}x_p (t,\varepsilon ) \hfill \\ \varepsilon ^{h_2 } \frac{{d{\text{ }}x_2 }}{{d{\text{ }}t}} = A_{21} (t,\varepsilon ){\text{ }}x_1 (t,\varepsilon ){\text{ }} + \cdots + A_{2p} (t,\varepsilon ){\text{ }}x_p (t,\varepsilon ) \hfill \\ {\text{ }} \vdots {\text{ }} \vdots {\text{ }} \vdots \hfill \\ \varepsilon ^{h_p } \frac{{d{\text{ }}x_2 }}{{d{\text{ }}t}} = A_{p1} (t,\varepsilon ){\text{ }}x_1 (t,\varepsilon ){\text{ }} + \cdots + A_{pp} (t,\varepsilon ){\text{ }}x_p (t,\varepsilon ) \hfill \\ \end{gathered} \right\} \hfill \\ {\text{ }}R(\varepsilon ){\text{ }}x(a,{\text{ }}\varepsilon ){\text{ }} + {\text{ }}S(\varepsilon ){\text{ }}x(b,{\text{ }}\varepsilon ) = c(\varepsilon ){\text{ }} \hfill \\ \end{gathered}$$  相似文献   

19.
In order to capture the complexities of two-phase flow in heterogeneous porous media, we have used the method of large-scale averaging and spatially periodic models of the local heterogeneities. The analysis leads to the large-scale form of the momentum equations for the two immiscible fluids, a theoretical representation for the large-scale permeability tensor, and a dynamic, large-scale capillary pressure. The prediction of the permeability tensor and the dynamic capillary pressure requires the solution of a large-scale closure problem. In our initial study (Quintard and Whitaker, 1988), the solution to the closure problem was restricted to the quasi-steady condition and small spatial gradients. In this work, we have relaxed the constraint of small spatial gradients and developed a dynamic solution to the closure problem that takes into account some, but not all, of the transient effects that occur at the closure level. The analysis leads to continuity and momentum equations for the-phase that are given by
  相似文献   

20.
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   

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