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Computational Progress in Linear and Mixed Integer Programming

Gurobi_Progress_LP_MIP

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Example 3: A typical situation<br />

today – Supply-cha<strong>in</strong> schedul<strong>in</strong>g<br />

▸<br />

▸<br />

▸<br />

Model description:<br />

◦ Weekly model, daily buckets: Objective to m<strong>in</strong>imize<br />

end-of-day <strong>in</strong>ventory.<br />

◦ Production (s<strong>in</strong>gle facility), <strong>in</strong>ventory, shipp<strong>in</strong>g<br />

(trucks), wholesalers (dem<strong>and</strong> known)<br />

Initial model<strong>in</strong>g phase<br />

◦ Simplified prototype + complicat<strong>in</strong>g constra<strong>in</strong>ts<br />

(production run group<strong>in</strong>g req’t, m<strong>in</strong> truck<br />

constra<strong>in</strong>ts)<br />

◦ RESULT: Couldn’t get good feasible solutions.<br />

Decomposition approach<br />

◦ Talk to current schedul<strong>in</strong>g team: They first decide<br />

on “producibles” schedule. Simulate us<strong>in</strong>g heuristics.<br />

◦ Fixed model: Fix variables <strong>and</strong> run MIP<br />

© 2015 Gurobi Optimization<br />

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