A major drawback in optimization problems and in particular in scheduling problems is that for every measure there may be a different optimal solution. In many cases the various measures are different lp norms. We address this problem by introducing the concept of an All-norm ρ-approximation algorithm, which supplies one solution that guarantees ρ-approximation to all lp norms simultaneously. S...

A common approach to deal with NP-hard problems is to deploy polynomial-time -approximation algorithms. These algorithms often resort to rounding and scaling to guarantee a solution that is within a factor (1 + ) of the optimal solution. Usually, researchers either only round up or only down. In this paper we will evaluate the gain in accuracy when rounding up and down. The main application of ...

This paper deals with the problem of broadcasting in minimum time in the telephone and message-passing models. Approximation algorithms are developed for arbitrary graphs, as well as for several restricted graph classes. In particular, an O(p n)-additive approximation algorithm is given for broadcasting in general graphs, and an O(log log n= log n) (multiplicative) ratio approximation is given ...