754 research outputs found
Hierarchical Routing over Dynamic Wireless Networks
Wireless network topologies change over time and maintaining routes requires
frequent updates. Updates are costly in terms of consuming throughput available
for data transmission, which is precious in wireless networks. In this paper,
we ask whether there exist low-overhead schemes that produce low-stretch
routes. This is studied by using the underlying geometric properties of the
connectivity graph in wireless networks.Comment: 29 pages, 19 figures, a shorter version was published in the
proceedings of the 2008 ACM Sigmetrics conferenc
Hitting probabilities for non-linear systems of stochastic waves
We consider a -dimensional random field that solves a
non-linear system of stochastic wave equations in spatial dimensions , driven by a spatially homogeneous Gaussian noise that is white in
time. We mainly consider the case where the spatial covariance is given by a
Riesz kernel with exponent . Using Malliavin calculus, we establish
upper and lower bounds on the probabilities that the random field visits a
deterministic subset of \IR^d, in terms, respectively, of Hausdorff measure
and Newtonian capacity of this set. The dimension that appears in the Hausdorff
measure is close to optimal, and shows that when , points
are polar for . Conversely, in low dimensions , points are not polar.
There is however an interval in which the question of polarity of points
remains open.Comment: 85 page
Recommended from our members
Cold Nuclear Matter effects on J/psi production at RHIC: comparing shadowing models
We present a wide study on the comparison of different shadowing models and their influence on J/{psi} production. We have taken into account the possibility of different partonic processes for the c{bar c}-pair production. We notice that the effect of shadowing corrections on J/{psi} production clearly depends on the partonic process considered. Our results are compared to the available data on dAu collisions at RHIC energies. We try different break up cross section for each of the studied shadowing models
- âŠ