CONVERGENCE RATES FOR THE COMPRESSIBLE NAVIER-STOKES EQUATIONS WITH GENERAL FORCES

For the viscous and heat-conductive fluids governed by the compressible Navier- Stokes equations with external force of general form in R^3, there exist nontrivial stationary solutions provided the external forces are small in suitable norms, which was studied in article [15], and there we also proved the global in time stability of the stationary solutions with respect to initial data in H^3-framework. In this article, the authors investigate the rates of convergence of nonstationary solutions to the corresponding stationary solutions when the initial data are small in H^3 and bounded in L6/5.     

非平稳NA序列中心极限定理的一些结果

本文讨论了非平稳同分布ＮＡ序列的渐近正态问题，给出了两个中心极限定理，以往的文献在讨论ＮＡ序列的这些问题时，多加有强平稳的限制；但是大量问题所出现的ＮＡ序列却多为非平稳的，因此有开展研究的必要。本文在寻求摆脱平稳性限制的途径方面作了有益的尝试，所得的定理不仅可解决一大类非平稳ＮＡ序列的渐近正态问题，而且将以往的强平稳场合的结果包含为特例，具有一定的理论意义与应用价值。     

Asymptotic stability of the spectrum of a parametric family of homogenization problems associated with a perforated waveguide

In this paper, we provide uniform bounds for convergence rates of the low frequencies of a parametric family of problems for the Laplace operator posed on a rectangular perforated domain of the plane of height H. The perforations are periodically placed along the ordinate axis at a distance $O(\epsilon )$ between them, where ε is a parameter that converges toward zero. Another parameter η, the Floquet-parameter, ranges in the interval $[-\pi ,\pi ]$. The boundary conditions are quasi-periodicity conditions on the lateral sides of the rectangle and Neumann over the rest. We obtain precise bounds for convergence rates which are uniform on both parameters ε and η and strongly depend on H. As a model problem associated with a waveguide, one of the main difficulties in our analysis comes near the nodes of the limit dispersion curves.