783 search results - page 86 / 157 » Improved approximation algorithms for the freeze-tag problem |
STOC
2012
ACM
11 years 11 months ago
2012
ACM
We consider the problem of computing the k-sparse approximation to the discrete Fourier transform of an ndimensional signal. We show: • An O(k log n)-time randomized algorithm f...
ESA
2009
Springer
14 years 3 months ago
2009
Springer
Dial-a-Ride problems consist of a set V of n vertices in a metric space (denoting travel time between vertices) and a set of m objects represented as source-destination pairs {(si,...
ESA
2009
Springer
14 years 3 months ago
2009
Springer
We consider the problem of representing, in a space-efficient way, a function f : S → Σ such that any function value can be computed in constant time on a RAM. Specifically, ou...
KDD
2003
ACM
14 years 9 months ago
2003
ACM
Several important time series data mining problems reduce to the core task of finding approximately repeated subsequences in a longer time series. In an earlier work, we formalize...
CORR
2010
Springer
13 years 8 months ago
2010
Springer
We consider the problem of maximizing a nonnegative (possibly non-monotone) submodular set function with or without constraints. Feige et al. [9] showed a 2/5-approximation for th...