An improved approximation scheme for the Group Steiner Problem
β Scribed by C. S. Helvig; Gabriel Robins; Alexander Zelikovsky
- Publisher
- John Wiley and Sons
- Year
- 2000
- Tongue
- English
- Weight
- 322 KB
- Volume
- 37
- Category
- Article
- ISSN
- 0028-3045
No coin nor oath required. For personal study only.
β¦ Synopsis
the Group Steiner Problem asks for a minimumcost tree which contains at least one node from each group N i N i N i . In this paper, we give polynomial-time O O O(k k k )approximation algorithms for any fixed > > > 0. This result improves the previously known O O O(k k k)-approximation. We also apply our approximation algorithms to the Steiner problem in directed graphs, while guaranteeing the same performance ratio.
π SIMILAR VOLUMES
An improved projection scheme is proposed and applied to pseudospectral collocation-Chebyshev approximation for the incompressible Navier-Stokes equations. It consists of introducing a correct predictor for the pressure, one which is consistent with a divergence-free velocity field at each time step