IEOR PhD preparation: What are the essential courses?

Title says all. Personal research interests include stochastic modeling and applied dynamical systems(possibly machine learning) - all of which may be applicable for stat/ieor/applied math.  Could anyone please offer some suggestions as for the essential courses for potential IEOR PhD applicants? Are there big differences between IEOR prep work and stat prep work? Many thanks.

Sorry for typing English here - school computer has no Chinese input.

IEOR偏计算吧，你可以去找找计算数学的课，比如数值分析有限元，运筹学最优化啥的