Dynamic lot sizing with product returns

摘要: We address the dynamic lot sizing problem for systems with product returns. The demand and return amounts are deterministic over finite planning horizon. Demands can be satisfied by manufactured new items, but also remanufactured returned items. objective is to determine those sizes manufacturing remanufacturing that minimize total cost composed of holding returns (re)manufactured products set-up costs. Two different schemes considered; there either a joint (single production line) or separate costs (dedicated lines). For case, we present an exact, polynomial time programming algorithm. both cases, suggest modifications well-known Silver Meal (SM), Least Unit Cost (LUC) Part Period Balancing (PPB) heuristics. An extensive numerical study reveals number insights. key ones under schemes: (1) SM LUC heuristics perform much better than PPB, (2) increased variation in lead reduced cost, showing predictability more important variation, (3) periods should, if possible, avoided ’matching’ return.