When demand varies over time and production capacity changes across periods, disaggregation requires rolling-horizon heuristics with periodic replanning. Safety stock and reorder points are introduced to buffer stochastic demand; discrete demand formulations replace continuous approximations. The approach estimates equivalent uniform demand over a planning window, sequences products via inventory ratios, applies linear programming for cycle optimization, then updates demand forecasts and inventory positions at each replanning point. Table of Contents: • Time-varying demand: demand differs both across time and compared to production capacity • Equivalent uniform demand: averaging demand over estimated cycle window for heuristic sequencing • Safety stock purpose: buffer against demand uncertainty and forecast errors • Reorder point (ROP) for discrete demand: threshold trigger for order placement • Planning window estimate: r + 1/r heuristic for cycle length approximation • Weighted demand calculation: time-proportional demands over multiple periods • Rolling horizon approach: solve first cycle, update inventory and forecasts, repeat • Lead time impact on inventory position and safety stock requirements • Deterministic assumption relaxation: handling demand variability through inventory buffers • Transient vs. steady-state models: practical simplified steady-state approach for rolling forecasts • Practical implementation: inventory position updates at cycle boundaries with demand revision
When demand varies over time and production capacity changes across periods, disaggregation requires rolling-horizon heuristics with periodic replanning. Safety stock and reorder points are introduce…