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101.
Periodic Solutions of Delay Differential Equations with a Small Parameter: Existence,Stability and Asymptotic Expansion 总被引:1,自引:0,他引:1
Chunhua?Ou Jianhong?WuEmail author 《Journal of Dynamics and Differential Equations》2004,16(3):605-628
We consider a scalar delay differential equation with a small parameter, and employ Walthers method to obtain a result on the existence and stability of a slowly oscillatory periodic solution that represents a refinement of the estimate for the Lipschitz constant of a returning map. We also develop a matching method and obtain asymptotic expansions of the slowly oscillatory periodic solution and its minimal period.Dedicated to Professor Shui-Nee Chow on the occasion of his 60th birthdayAMS subject classifications: 34K15; 34K20; 34C25. 相似文献
102.
张祥 《应用数学和力学(英文版)》1994,(3)
SINGULARPERTURBATIONOFINITIALBOUNDARYVALUEFROBLEMSOFREACTIONDIFFUSlONEQUATIONWITHDELAYZhangXiang(张祥)(AnhuiNormalUniversity)Wu... 相似文献
103.
定量开采条件下径向渗流的液固耦合问题 总被引:2,自引:0,他引:2
考虑到多孔介质渗透率随孔隙度变化的特点,建立了力学模型,研究定量抽放问题;对于广义平面应力状态下的非线性渗流耦合问题,提出了解的构造方法和解耦方法;求出了耦合条件下的孔隙压力,多孔介质总应力、总应变和总位移的解析解;进行了实例计算,并与Biot理论进行了对比,结果表明两种理论的差别很大。因此在渗透系数有较明显变化的场舍下不能采用Biot理论进行分析。 相似文献
104.
本文简述同伦分析方法基本思想、最新理论进展及其在流体力学、固体力学、一般力学、量子力学、应用数学、金融等科学和工程领域的应用.同伦分析方法不依赖物理小参数, 适用范围更广,而且提供了一种简单的途径确保级数解收敛, 适用于强非线性问题.同伦分析方法已被成功应用于求解一些具有挑战性的力学问题,并获得一些全新的、 从未见报道的解. 这些成功的应用,证明了同伦分析方法的普遍有效性和原创性. 相似文献
105.
The flow of a second-grade fluid past a porous plate subject to either suction or blowing at the plate has been studied. A
modified model of second-grade fluid that has shear-dependent viscosity and can predict the normal stress difference is used.
The differential equations governing the flow are solved using homotopy analysis method (HAM). Expressions for the velocity
have been constructed and discussed with the help of graphs. Analysis of the obtained results showed that the flow is appreciably
influenced by the material and normal stress coefficient. Several results of interest are deduced as the particular cases
of the presented analysis. 相似文献
106.
A. M. Zenkour 《Archive of Applied Mechanics (Ingenieur Archiv)》2004,74(3-4):262-276
Summary The static and dynamic responses of anisotropic spherical shells under a uniformly distributed transverse load are investigated.
Analytical solutions using the mixed variational formulation are presented for spherical shells subjected to various boundary
conditions. Numerical results of a refined mixed first-order shear deformation theory for natural frequencies, critical buckling,
center deflections and stresses are compared with those obtained using the classical shell theory. A variety of simply-supported
and clamped boundary conditions are considered and comparisons with the existing literature are made. The sample numerical
results presented herein for global structural behaviour of monoclinic spherical shells should serve as references for future
comparisons. 相似文献
107.
Noureddine Mehidi 《Meccanica》2007,42(4):403-407
We first approximate the solutions of the nonautonomous oscillating suspension point pendulum equation by the solutions of
a second order autonomous differential equation. Using the strict monotonicity of the periodic solutions of the approximating
equation, we prove the existence of a large number of subharmonic periodic solutions of the plane pendulum when its point
of suspension is excited parametrically. 相似文献
108.
Eiji Yanagida 《Journal of Dynamics and Differential Equations》2002,14(1):189-205
The purpose of this paper is to introduce a reaction-diffusion system with skew-gradient structure and discuss the stability of standing pulse solutions. In short, the skew-gradient system is a reaction-diffusion system which resembles a gradient system but has nonlinearities with different sign. We assume the existence of a standing pulse solution and define its orientation in some geometrical manner. Then we show that the stationary solution becomes unstable if time constants satisfy some inequality. The Evans function plays a crucial role for the stability analysis. 相似文献
109.
The quasi-parallel regime of a Darcy–Boussinesq boundary-layer flow over a permeable vertical flat plate adjacent to a fluid saturated porous medium is considered. Quasi-parallel means here a plane flow with a constant transversal velocity v=–v
0 directed perpendicularly towards the vertical surface, where a lateral suction with the same velocity –v
0 is applied. The plate is held at a constant temperature T
w which coincides with the ambient temperature T
of the fluid. The heat released by viscous dissipation induces a density gradient in the fluid. Thus, although T
w=T
, a thermal convection occurs. The steady regime of this self-sustaining buoyant flow has been examined in detail. Wall jet-like profiles with a continuous but finite spectrum of the momentum flow have been found. These self-sustaining buoyant jets show a universal behavior, that is, there exist certain length, velocity and temperature scales such that the flow characteristics become independent of the (constant) material properties of the fluid and the porous medium as well. 相似文献
110.
In this paper, a characteristic equation involving the stream function, already given by one of the authors in a previous work for classifying axisymmetric incompressible flows, is re-considered. Non-uniform nearly extensional flows are derived as particular solutions from this equation. Using experimental data in the literature for polymer solutions and melts, it is proved that particular solutions of the characteristic equation lead to kinematics very close to those encountered in the fiber-spinning process. The kinematic equations satisfactorily correlating the fiber-spinning data are used in order to determine the ability of constitutive equations to predict realistic stresses in the flow domain. The rheological parameters of the fluids, obtained from experiments, are used for computation of differential and integral constitutive equations in the spinning conditions. Comparisons with the stress response of adequate constitutive equations are given and discussed.Also affiliated to: Université Joseph Fourier Grenoble I and Institut National Polytechnique de Grenoble, Associé au CNRS (URA 1510) 相似文献