| Article ID: | iaor19991657 |
| Country: | Netherlands |
| Volume: | 103 |
| Issue: | 1 |
| Start Page Number: | 113 |
| End Page Number: | 116 |
| Publication Date: | Nov 1997 |
| Journal: | European Journal of Operational Research |
| Authors: | Gladky A.A. |
This paper deals with a two-machine preemptive openshop system processing a set of jobs with different ready dates. The problem of minimizing the mean flow time is known to be strongly NP-complete. We re-prove this fact in an elementary way.