944 resultados para upwind compact difference schemes on non-uniform meshes
Resumo:
Refractive smoothing of weak non-uniformities in the illumination of laser targets is analyzed, assuming absorption at the critical density and restricting conduction to a thin layer, and using results from thermal smoothing, which is uncoupled from the refraction. Magnetic effects are included. Non-uniformity wavelengths comparable to the thickness of the conduction layer are considered; efficient smoothing exists at both short and long wavelengths in this range. Thermal focusing could make the ablated plasma unstable.
Resumo:
We develop general closed-form expressions for the mutual gravitational potential, resultant and torque acting upon a rigid tethered system moving in a non-uniform gravity field produced by an attracting body with revolution symmetry, such that an arbitrary number of zonal harmonics is considered. The final expressions are series expansion in two small parameters related to the reference radius of the primary and the length of the tether, respectively, each of which are scaled by the mutual distance between their centers of mass. A few numerical experiments are performed to study the convergence behavior of the final expressions, and conclude that for high precision applications it might be necessary to take into account additional perturbation terms, which come from the mutual Two-Body interaction.
Resumo:
In the context of real-valued functions defined on metric spaces, it is known that the locally Lipschitz functions are uniformly dense in the continuous functions and that the Lipschitz in the small functions - the locally Lipschitz functions where both the local Lipschitz constant and the size of the neighborhood can be chosen independent of the point - are uniformly dense in the uniformly continuous functions. Between these two basic classes of continuous functions lies the class of Cauchy continuous functions, i.e., the functions that map Cauchy sequences in the domain to Cauchy sequences in the target space. Here, we exhibit an intermediate class of Cauchy continuous locally Lipschitz functions that is uniformly dense in the real-valued Cauchy continuous functions. In fact, our result is valid when our target space is an arbitrary Banach space.
Resumo:
This paper aims to estimate the crowding-out effect of the Danish mandatory labour market pension reforms begun in 1993 on the level of total household savings for renters. The effect is identified via a large panel of individual administrative records utilising the differences in speed, timing and sectoral coverage of the implementation of the reform in the period 1997 to 2005. Little substitutability was found between current mandatory labour market pension savings and private voluntary savings. Each euro paid into mandatory labour market pension accounts results in a reduction in private savings of approximately 0 to 30 cents, depending on age. This low rate of substitution is only, to a minor extent, explained by liquidity constraints. The results point to mandatory pension savings having a large effect on total household savings. Thus, pension reforms that introduce mandatory savings have macroeconomic implications.