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311.
对拟线性椭圆变分不等式的障碍最优控制问题(即以障碍为控制变量)进行了研究.指标泛函为Lagrange型,其中含有控制变量二阶导数的p次幂,这使得最优性条件的推导颇为不易.对所考虑的问题给出了最优控制的存在性定理以及必要条件. 相似文献
312.
313.
We identify a class of instances of the Koopmans–Beckmann form of the Quadratic Assignment Problem that are solvable in polynomial time. This class is characterized by a path structure in the flow data and a grid structure in the distance data. Chr18b, one of the test problems in the QAPLIB, is in this class even though this feature of it has not been noticed until now. 相似文献
314.
Bing Yong HSIE 《数学学报(英文版)》2006,22(2):507-514
This paper gives a p-adic analogue of the Mackey theory, which relates representations of a group of type G - H × t A to systems of imprimitivity. 相似文献
315.
316.
Igor Chueshov 《Journal of Differential Equations》2007,233(1):42-86
We study von Karman evolution equations with non-linear dissipation and with partially clamped and partially free boundary conditions. Two distinctive mechanisms of dissipation are considered: (i) internal dissipation generated by non-linear operator, and (ii) boundary dissipation generated by shear forces friction acting on a free part of the boundary. The main emphasis is given to the effects of boundary dissipation. Under suitable hypotheses we prove existence of a compact global attractor and finiteness of its fractal dimension. We also show that any solution is stabilized to an equilibrium and estimate the rate of the convergence which, in turn, depends on the behaviour at the origin of the functions describing the dissipation. 相似文献
317.
Differential inequality method, bounding function method and topological degree are applied to obtain the existence criterions of at least one solution for the general fourth-order differential equations under nonlinear boundary conditions, and many existing results are complemented. 相似文献
318.
Armen Shirikyan 《Journal of Functional Analysis》2007,249(2):284-306
The paper is devoted to studying the distribution of stationary solutions for 3D Navier-Stokes equations perturbed by a random force. Under a non-degeneracy assumption, we show that the support of such a distribution coincides with the entire phase space, and its finite-dimensional projections are minorised by a measure possessing an almost surely positive smooth density with respect to the Lebesgue measure. Similar assertions are true for weak solutions of the Cauchy problem with a regular initial function. The results of this paper were announced in the short note [A. Shirikyan, Controllability of three-dimensional Navier-Stokes equations and applications, in: Sémin. Équ. Dériv. Partielles, 2005-2006, École Polytech., Palaiseau, 2006]. 相似文献
319.
Kiyoshi Mochizuki 《Journal of Mathematical Analysis and Applications》2007,326(1):582-588
We show that the energy of solutions to the initial boundary value problem for the wave equation in exterior domains with a dissipation which is localized only near infinity tends to zero as the time goes to infinity. We do not make any geometrical condition like star-shapedness on the boundary. 相似文献
320.
The authors give a consistent affirmative response to a question of Juhász, Soukup and Szentmiklóssy: If GCH fails, there are (many) extraresolvable, not maximally resolvable Tychonoff spaces. They show also in ZFC that for ω<λ?κ, no maximal λ-independent family of λ-partitions of κ is ω-resolvable. In topological language, that theorem translates to this: A dense, ω-resolvable subset of a space of the form (DI(λ)) is λ-resolvable. 相似文献