An integrated cutting stock and lot sizing problem

Şanan, Ayşe Burcu
In this thesis, we consider an integrated two dimensional cutting stock and lot sizing problem arising in an aircraft manufacturing plant. The items are to be cut from steel panels of identical size to satisfy all periodic demands over a specified planning horizon. Two objectives, minimizing the number of panels cut and total inventory carrying cost of the items, are defined and all nondominated objective vectors with respect to the defined objectives are generated. To generate each nondominated objective vector, we propose a mixed integer linear programming model whose efficiency is improved by optimality properties and bounding mechanisms. We propose a decomposition-based heuristic algorithm to solve the instances having the smallest number of panels. The results of our experiments based on real data and data taken from the literature have revealed that the instances with few items can be solved for up to 14 periods and the instances with more items can be solved for up to 7 periods, within our termination limit of two hours.


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This study considers the serial lot sizing problem with backlogging in two-level supply chains to determine when and how much to order at a warehouse and ship to a retailer over a T-period planning horizon so that the external known demand occurring at the retailer is satisfied and the total cost at all levels is minimized. In particular, the uncapacitated two-level serial lot sizing problem with backlogging and the two-level serial lot sizing problem with cargo capacity and backlogging are formulated using...
Citation Formats
A. B. Şanan, “An integrated cutting stock and lot sizing problem,” M.S. - Master of Science, Middle East Technical University, 2021.