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991.
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
992.
中立型抛物方程解的强迫振动性 总被引:2,自引:0,他引:2
本文讨论中立型抛物方程解的强迫振动,其中Ω是Rn中具有光滑边界Ω的有界区域, 相似文献
993.
Mingyu Xu 《Journal of Theoretical Probability》2007,20(4):1005-1039
In this paper, we prove the existence and uniqueness result of the reflected BSDE with two continuous barriers under monotonicity
and general increasing condition on y, with Lipschitz condition on z. 相似文献
994.
This paper deals with a class of equilibria which are based on the use of memory strategies in the context of continuous-time stochastic differential games. In order to get interpretable results, we will focus the study on a stochastic differential game model of the exploitation of one species of fish by two competing fisheries. We explore the possibility of defining a so-called cooperative equilibrium, which will implement a fishing agreement. In order to obtain that equilibrium, one defines a monitoring variable and an associated retaliation scheme. Depending on the value of the monitoring variable, which provides some evidence of a deviation from the agreement, the probability increases that the mode of a game will change from a cooperative to a punitive one. Both the monitoring variable and the parameters of this jump process are design elements of the cooperative equilibrium. A cooperative equilibrium designed in this way is a solution concept for a switching diffusion game. We solve that game using the sufficient conditions for a feedback equilibrium which are given by a set of coupled HJB equations. A numerical analysis, approximating the solution of the HJB equations through an associated Markov game, enables us to show that there exist cooperative equilibria which dominate the classical feedback Nash equilibrium of the original diffusion game model.This research was supported by FNRS-Switzerland, NSERC-Canada, FCAR-Quebec. 相似文献
995.
1IntroductionWeshalbeconcernedherewithrealfifthordervectordiferentialequationoftheform:X(5)+F(X..)X(4)+Φ(X..)+G(X..)+H(X.)+Ψ... 相似文献
996.
Logarithmic norms are often used to estimate stability and perturbation bounds in linear ODEs. Extensions to other classes of problems such as nonlinear dynamics, DAEs and PDEs require careful modifications of the logarithmic norm. With a conceptual focus, we combine the extension to nonlinear ODEs [15] with that of matrix pencils [10] in order to treat nonlinear DAEs with a view to cover certain unbounded operators, i.e. partial differential algebraic equations. Perturbation bounds are obtained from differential inequalities for any given norm by using the relation between Dini derivatives and semi-inner products. Simple discretizations are also considered. 相似文献
997.
998.
A theoretical model reproducing qualitative and quantitative characteristics of DSC traces for melting of eutectic enantiomeric
mixtures was proposed. The method for reconstruction of an idealized trace from a fragment of the real experimental melting
curve was developed. When studying a sample of intermediate enantiomeric composition, the reconstruction of the trace makes
it possible to avoid ambiguity in determination of the liquidus temperature, determine the melting temperature for an enantiopure
compound, and estimate the composition of the sample.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1288–1293, July, 2007. 相似文献
999.
二维轴对称图象高阶胡氏不变矩快速算法的改进 总被引:2,自引:2,他引:0
提出了基于二维轴对称性目标图象矩快速算法的实用化改进方案.算法实用化改进是通过两个命题的证明实现的.一是通过轴对称目标图象质心在对称轴上的命题证明,实现了将二维轴对称图象矩快速算法用于轴对称性图象中心矩的计算;二是通过目标图象以坐标系中任意两点为圆心,旋转相同角度,结果图象具有平移性的命题证明,实现了算法用于对旋转不同角度的对称目标图象的中心矩的计算改进.在此基础上,完成了二维轴对称目标图象高阶胡氏不变矩实用化快速算法的实现.实验证明,该算法具有较好的实时性能,且具有较小的引入误差. 相似文献
1000.