New Challenges in Scheduling Theory

October 21 - 27, 2012 --- Centre CNRS "La Villa Clythia", Frejus, France

Weighted Completion Time Minimization on a Single-Machine with a Fixed Non-Availability Interval: Differential Approximability

SpeakerImed Kacem

Coauthor: Vangelis Th. Paschos

This work is the first successful attempt on differential approximability study for a scheduling problem. Such a study considers the weighted completion time minimization on a single machine with a fixed non-availability interval. The analysis shows that the Weighted Shortest Processing Time (WSPT) rule cannot yield a differential approximation for the studied problem in the general case. Nevertheless, a slight modification of this rule provides an approximation with a differential ratio of (3-√5)/2 ≈ 0.38.