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1.
51.IntroductionConsideralinearintegrodifferentialsystemswithtime-variedconfficientswherex6R",A(t)isanXnrealmatrixfunctioncontinuousforoO.ManyscholarshavecontributedtheirpaPers[1-4]todiscussstabilityofzerosolutionofsystem(1.l).Inthispaper,weassumethatsystem(1.1)canbedecomPOsedintotheform=n,A,j(t)isaniXnjrealmatrixfunctioncontinuousforo相似文献   

2.
61.IntroductionConsiderthesecondordersuperlinearequationx'(t) p(t)X'(t) q(t)1x(t)l"sgnx(t)=o,t>to,(1)wherea>l,pandq:[t,'co)-R=(-co,oo)arecontinuous.Weconsideronlysuchsolutionsxofequation(l)whichexistonsomeinterval[t.,oo),t.>t,>o.Asolutionofequation(l)issaidtobeoscillatoryifithasarbitrarilylargezerosandotherwise,itissaidtobenonoscillatory.Equation(l)iscalledoscillatoryifallofitssolutionsareoscilllatory.Forthespecialcasewherep(t)=Oli.e.,forthedifferentialequationx'(t) q(t)lx(t)l"sgnx(t)=o,a>1-…  相似文献   

3.
1IntroductionInthispaper,wediscussthecompletesolutionoftheLinearNon-HomogeneousMatrixDifferentialEquations(LNHMDEs)describedbyA(p)PNH(t)=B(p)U(t),t2o,(1)wherepgd/dtthedifferentialoperator,A(p)=A,,Pq' A,,-1Pq1-' ' A1p AoERfa],",,rankR(.)A(p)=rlAieR",,i=O,1,2,',qi,qi>1,B(p)=Blpl BI-,P,-' -.' B1p BOeR[P],'",BjER'",j=o,1,2,...,l,l2o,PNH(t):[o, oc)-R'isthepseudostateoftheLNHMDE,u(f):[o, oo)-R"isanitimespiecewisecontinuouslydifferentiablefunctioncalledtheinputoftheLNHMDE…  相似文献   

4.
二阶非线性微分议程解的平方可积性与有界性(英文)   总被引:2,自引:0,他引:2  
1 IntroductionIn this paPer, we consider the second order nonlinear differential equationwhere r(t) > 0 fOr t E [a, oo) and r(t) is absolutely continuous on [a, oc), p, q1and q2 are real functions defined on [a, oo) and f is a real function defined on[a, oo) x (--oc, oo) which satisfieswhere 0 S cr S 1, g(t) 2 0 and h(t) 2 0 for t E [a, oo).The behaviors of quadratic integrability and boundedness fOr some moreparticular forms of equation (l) such as have been studied (see [1--4]). And many …  相似文献   

5.
1 IntroductionConsider the red blood ceels growth model with several delayswhere r(t) E C([0, oo), (0, oo)), Pil ri) n e (0, oo), and r1 2 r2 2'' 2 rm.Eq.(l) was used first by Wazewska-Czyzewska and Lasota [l] as a model forthe survival of the red blood ceels in an animal, see also Arino and Kimmel[2]. There are a lot of activities concerning the asymptotic behavior of (1),see for examp1e [3] and the references cited therein. The following results wasobtained in [l, 3, 4].N'(t) = --pN(t)…  相似文献   

6.
周勇 《数学季刊》1997,12(1):38-42
51iIntroductionConsidertheneutralequationwithvariablecoefficientsInrecentyears,thedscillatotytheoryforneutralequathaiswelldeveloped.Inparticular,manydifferentsuffitientconditionsfortheoscillationofallsolutionsofEq.(l)areobtainedin[l-7j.Allthepapersmentionedexcept[6],however,alwaysassumeP(t)isinoneofthefOllowingranges:OSP(t)SlorP(t)2l.Ouraiminthispapertoeatablishnewsufficientcon-ditionsfortheoscillationofallsolutiOnsofEq.(l)underlessrestrictivehypothesesonP(t).Letm=max{Y,d}.Byasolutionof…  相似文献   

7.
1IntroductionConsidertheneutraldifferentialequationswherepiERfori=l,2,...,m;o相似文献   

8.
郝涌 《数学季刊》1997,12(3):20-23
61.IntroductionLetXbeaBanachspace,B(X)thealgebraofallboundedlinearoPeratoronXandC(t),t6R,thestronglycontinuouscosineoperatorfunctionsonXwithinfinitesimalgeneratorA,TheFavard(orSaturation)classorgeneralizedFav(A)ofcosineoperatorfuctionC(t)withgeneratorAisdefinedbyFav(A)={x:supl,1<,Il2t~'(C(t)-I)xllX oo}.Theestimater'P,llC(t)x-xIl=IlAJoJoC(p)xdedsIl相似文献   

9.
傅希林 《数学季刊》1991,6(1):109-110
本文研究具有变滞量的一阶刀夕刀E共[二(,)一。(,)二(,一,)〕+,(,)二〔,一:(,)〕=。,,),。Q了(1)的振动性.文中始终假设::,c,P:[t0,sup:(,)些。<,co,lim[t一r(t)]=+oo,瞪r氏叮睁甘阵卜少E.A.Grove,M.R.S.Kulenovi亡和G.+co),R+连续,r>0,0(c(t)(1(t》t。);存在常数K>o,使得。(K《p(t)(t)t。).Ladas[i]研究了方程(1)中了(t)三eonst.>0的情形,而本文考虑变滞量的情形,给出了方程(1)当。0且y‘(t)(0. …  相似文献   

10.
1IntroductionInthispaper,weintendtostudytheexistenceoftheglobalattractorforthefollowinginitialvalueproblemofGinzburgLandauequationcoupledwithBBMequationinanunboundeddomainR=(-oo,oo)wheree(x,f)isacomplexfunction,n(x,t)isarealscalarfunction,pty,6,T,cr1,a2,P1,P2arerealcoustants,andg1(x),g2(x)aregivenrealfunctions.ThisproblemdescribesthenonlinearinteractionsbetweentheLangnluirwaveandtheionacousticwaveinplasmaphysics,E(z,t)denoteselectricfield,n(x,t)betheperturbationofdensity(see[2,12,6l).In[7]…  相似文献   

11.
It is well known that a scalar differential equation , where f(t,x) is continuous, T-periodic in t and weakly convex or concave in x has no, one or two T-periodic solutions or a connected band of T-periodic solutions. The last possibility can be excluded if f(t,x) is strictly convex or concave for some t in the period interval. In this paper we investigate how the actual number of T-periodic solutions for a given equation of this type in principle can be determined, if f(t,x) is also assumed to have a continuous derivative . It turns out that there are three cases. In each of these cases we indicate the monotonicity properties and the domain of values for the function P(ξ)=S(ξ)−ξ, where S(ξ) is the Poincaré successor function. From these informations the actual number of periodic solutions can be determined, since a zero of P(ξ) represents a periodic solution.  相似文献   

12.
13.
In this paper, we study solution structures of the following generalized Lennard-Jones system in R~n,x=(-α/|x|~(α+2)+β/|x|~(β+2))x,with 0 α β. Considering periodic solutions with zero angular momentum, we prove that the corresponding problem degenerates to 1-dimensional and possesses infinitely many periodic solutions which must be oscillating line solutions or constant solutions. Considering solutions with non-zero angular momentum, we compute Morse indices of the circular solutions first, and then apply the mountain pass theorem to show the existence of non-circular solutions with non-zero topological degrees. We further prove that besides circular solutions the system possesses in fact countably many periodic solutions with arbitrarily large topological degree, infinitely many quasi-periodic solutions, and infinitely many asymptotic solutions.  相似文献   

14.
This paper presents necessary and sufficient conditions for an n ‐th order differential equation to have a non‐continuable solution with finite limits of its derivatives up to the order l at the right‐hand end point of the interval of its definition, ln – 2 (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

15.
In this paper, we give a new proof for the fact that the distributional weak solutions and the viscosity solutions of the p-Laplace equation ?div(|Du| p?2 Du) = 0 coincide. Our proof is more direct and transparent than the original proof of Juutinen et al. [8 Juutinen , P. , Lindqvist , P. , Manfredi , J.J. ( 2001 ). On the equivalence of viscosity solutions and weak solutions for a quasi-linear equation . SIAM J. Math. Anal. 33 : 699717 .[Crossref], [Web of Science ®] [Google Scholar]], which relied on the full uniqueness machinery of the theory of viscosity solutions. We establish a similar result also for the solutions of the non-homogeneous version of the p-Laplace equation.  相似文献   

16.
对任意自然数n≥1,著名的Euler函数ψ(n)定义为不大于n且与n互素的正整数的个数.本文的主要目的是研究方程ψ(ψ(ψ(n)))=2ω(n)的可解性,其中ω(n)表示n的所有不同素因子的个数,并给出了该方程的所有正整数解.  相似文献   

17.
In this paper, we study the asymptotic behaviour as p→∞ of the radial solution of the problem
  相似文献   

18.
Some new results are given concerning the behavior of the oscillatory solutions of first or second order delay differential equations. These results establish that all oscillatory solutions x of a first or second order delay differential equation satisfy x(t)=O(v(t)) as t→∞, where v is a nonoscillatory solution of a corresponding first or second order linear delay differential equation. Some applications of the results obtained are also presented.  相似文献   

19.
The (2+1)-dimensional nonlocal nonlinear Schrödinger–Maxwell–Bloch system with PT-symmetric potentials will be investigated in this paper. The (2+1)-dimensional Darboux transformation will be constructed, some explicit solutions including periodic waves solutions, soliton solutions and complexiton solutions will be obtained under different backgrounds, and the interaction behaviors of those solutions will be discussed through some figures.  相似文献   

20.
两个数论函数及其方程   总被引:4,自引:0,他引:4  
对于任意给定的自然数n,著名的Eu ler函数φ(n)定义为不大于n且与n互素的正整数的个数.ω(n)表示n的所有不同素因子的个数.本文研究了方程φ(n)=2ω(n)的可解性,并给出了该方程的所有正整数解.  相似文献   

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