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| Indices | |
| i, h, p, m | A task |
| k | A worker |
| j | A multimanned station |
| n | The total number of tasks |
| M: | A big number |
| Ct | The given cycle time |
| fstip | The forward setup time between task i and task p |
| bstip | The backward setup time between task i and task p |
| Wmax | The maximum allowed number of workers in one station |
| Smax | The upper bound of number of multimanned station |
| Nmax | The maximum allowed number of tasks for each worker |
| P(i) | Set of all immediate predecessors of task i |
| Pa(i) | Set of all predecessors of task i |
| S(i) | Set of all immediate successors of task i |
| Sa(i) | Set of all successors of task i |
| WSk | Set of tasks assigned to worker k |
| θ | A controlling parameter between 0 and 1 |
|
| Parameters | |
| I | Set of tasks I = 1, 2, 3, … n, m |
| K | Set of workers K = 1, 2, 3, … Wmax |
| J | Set of stations J = 1, 2, 3, … Smax |
| WS | Set of positions WS = 1, 2, 3, … Nmax |
| ti | The task time of task i |
|
| Decision variables | |
| xijks | 1, if task i is assigned to the position s of station (j, k); 0, otherwise |
| fti | The finish time of task i |
| 1, if at least one task is assigned to station (j, k); 0, otherwise |
| WSjk | 1, if k workers are used in station j; 0, otherwise |
|
| Indicator variables | |
| zipjk | 1, if task i is assigned to the immediately predecessor position of task p in station (j, k); 0, otherwise |
| ltijk | 1, if task i is assigned to the last position of station (j, k); 0, otherwise |
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