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31.
32.
Abstract. We propose a general approach to deal with nonlinear, nonconvex variational problems based on a reformulation of the problem
resulting in an optimization problem with linear cost functional and convex constraints. As a first step we explicitly explore
these ideas to some one-dimensional variational problems and obtain specific conclusions of an analytical and numerical nature. 相似文献
33.
The formation of thinning filaments is commonly observed previously to the break-up of a very viscous jet. This paper shows that a fluid under capillary forces cannot break-up through the uniform collapse of a filament. 相似文献
34.
富勒烯 (C60 /C70 )与N ,N ,N′ ,N′ 四 (对甲苯基 ) 4,4′ 二胺 1,1′ 二苯硒醚 (TPDASe)间在激光光诱导条件下 ,发生了分子间的电子转移过程 .在可见 -近红外区 ( 60 0~ 12 0 0nm) ,观测到了TPDASe阳离子自由基、富勒烯 (C60 /C70 )激发三线态和阴离子自由基 ,在苯腈溶液中 ,观测瞬态谱测定了电子从TPDASe转移到富勒烯 (C60 /C70 )激发三线态的量子转化产率(ΦTet)和电子转移常数 (Ket) . 相似文献
35.
The existence of an attractor for a 2D-Navier-Stokes system with delay is proved. The theory of pullback attractors is successfully applied to obtain the results since the abstract functional framework considered turns out to be nonautonomous. However, on some occasions, the attractors may attract not only in the pullback sense but in the forward one as well. Also, this formulation allows to treat, in a unified way, terms containing various classes of delay features (constant, variable, distributed delays, etc.). As a consequence, some results for the autonomous model are deduced as particular cases of our general formulation. 相似文献
36.
In this paper, the detailed asymptotic behaviour of the solutions of a kinetic equation for quantum particles is studied. It is shown that this behaviour is sensitive not only to the total mass of the initial data but also to its precise behaviour near the origin. In some cases, solutions develop a Dirac mass at the origin for long times in a self-similar manner that is analysed in detail. 相似文献
37.
M Gubinelli 《Journal of Functional Analysis》2004,216(1):86-140
We formulate indefinite integration with respect to an irregular function as an algebraic problem which has a unique solution under some analytic constraints. This allows us to define a good notion of integral with respect to irregular paths with Hölder exponent greater than 1/3 (e.g. samples of Brownian motion) and study the problem of the existence, uniqueness and continuity of solution of differential equations driven by such paths. We recover Young's theory of integration and the main results of Lyons’ theory of rough paths in Hölder topology. 相似文献
38.
András Vasy 《Journal of Functional Analysis》2004,209(2):468-492
We show the exponential decay of eigenfunctions of second-order geometric many-body type Hamiltonians at non-threshold energies. Moreover, in the case of first-order and small second-order perturbations we show that there are no eigenfunctions with positive energy. 相似文献
39.
Marco Biroli Silvia Mataloni Michele Matzeu 《NoDEA : Nonlinear Differential Equations and Applications》2005,12(3):295-321
Some stability results for Mountain Pass and Linking type solutions of semilinear problems involving a very general class
of Dirichlet forms are stated. The non linear terms are supposed to have a suitable superlinear growth and the family of Dirichlet
forms is required to be dominated from below and from above by a fixed diffusion type form. Some concrete examples are also
given. 相似文献
40.
Michael T. Anderson 《Advances in Mathematics》2003,179(2):205-249
This paper studies several aspects of asymptotically hyperbolic (AH) Einstein metrics, mostly on 4-manifolds. We prove boundary regularity (at infinity) for such metrics and establish uniqueness under natural conditions on the boundary data. By examination of explicit black hole metrics, it is shown that neither uniqueness nor finiteness holds in general for AH Einstein metrics with a prescribed conformal infinity. We then describe natural conditions which are sufficient to ensure finiteness. 相似文献