| 초록 |
This work proposes a robust optimization approach for mid-term scheduling of a batch chemical plant which manufacture multiple products using multiple parallel units. Because a lot of tasks are processed during the mid-term scheduling horizon, the batch plant has the high uncertainty factors. Especially this work focuses on the uncertainty of processing times of tasks. To manage the uncertain events, it is a common method that each individual task is given a extra buffer duration. However, this method leads to the bloated schedule due to overestimate of the overall uncertainty. It is more efficient to consider the buffer on the chain of tasks rather than the individual tasks. In the mid-term scheduling, overall tasks can be decomposed to several subgroups by the final products, and the individual subgroups can be redefined by using complex tasks which consist of several consecutive tasks.The buffers for uncertainty are applied to these complex tasks. To demonstrate the proposed robust optimization, several examples are presented. |
