On Multi-product Lot-Sizing and Scheduling with Multi-machine Technologies
نویسندگان
چکیده
We consider a problem of multi-product lot-sizing and scheduling where each product can be produced by a family of alternative multi-machine technologies. Multi-machine technologies require one or more machine at the same time. A sequence dependent setup time is needed between different technologies. The criterion is to minimize the makespan. Preemptive and non-preemptive versions of the problem are studied. We formulate mixed integer linear programming models based on a continuous time representation for both versions of the problem. Using these models, the polynomially solvable cases of the problem are found. It is proved that the problem without setup times is strongly NPhard if there is only one product, and each technology occupies at most three machines. Besides that, problem cannot be approximated within a practically relevant factor of the optimum in polynomial time, if P6=NP.
منابع مشابه
Lot sizing with rework and different inspection costs
This paper deals with the single machine multi-product lot scheduling problem in which defective items are produced in any production run of each product. We have adopted the common cycle scheduling policy and assumed that the setup times for production of each product can be non-zero. Further, we have assumed that defective items will be reworked and the inspection costs during the normal prod...
متن کاملThe Finite Horizon Economic Lot Scheduling in Flexible Flow Lines
This paper addresses the common cycle multi-product lot-scheduling problem in flexible flow lines (FFL) where the product demands are deterministic and constant over a finite planning horizon. Objective is minimizing the sum of setup costs, work-in-process and final products inventory holding costs per time unite while satisfying the demands without backlogging. This problem consists of a combi...
متن کاملAn Extension of the Multi-machine Multi-level Proportional Lot Sizing and Scheduling Model for Product-Life-Cycle Demand
Often lot sizing and scheduling models have neglected the consideration of influence of product life cycles (PLCs). But, accordingly as desirable in a firm’s production strategy, decisions of lot sizing scheduling may have to respond to the stage changes in a product’s life cycle. In this paper, we propose an extension of the lot sizing scheduling, the multi-item, multi-level product-structure...
متن کاملSimultaneous Lot Sizing and Scheduling in a Flexible Flow Line
This paper breaks new ground by modelling lot sizing and scheduling in a flexible flow line (FFL) simultaneously instead of separately. This problem, called the ‘General Lot sizing and Scheduling Problem in a Flexible Flow Line’ (GLSP-FFL), optimizes the lot sizing and scheduling of multiple products at multiple stages, each stage having multiple machines in parallel. The objective is to satisf...
متن کاملOptimum Aggregate Inventory for Scheduling Multi-product Single Machine System with Zero Setup Time
In this paper we adopt the common cycle approach to economic lot scheduling problem and minimize the maximum aggregate inventory. We allow the occurrence of the idle times between any two consecutive products and consider limited capital for investment in inventory. We assume the setup times are negligible. To achieve the optimal investment in inventory we first find the idle times which minimi...
متن کامل