Lot sizing and furnace scheduling in small foundries |
| |
Authors: | Silvio A. de Araujo Marcos N. Arenales Alistair R. Clark |
| |
Affiliation: | 1. Instituto de Biociências, Letras e Ciências Exatas, Departamento de Ciências da Computação e Estatística, Universidade Estadual Paulista, São José do Rio Preto, SP 15054-000, Brazil;2. Instituto de Ciências Matemáticas e de Computação, Departamento de Matemática Aplicada e Estatística, Universidade de São Paulo, Caixa Postal 668, São Carlos, SP 13560-970, Brazil;3. Faculty of Computing, Engineering and Mathematical Sciences, University of the West of England, Bristol BS16 1QY, UK |
| |
Abstract: | A lot sizing and scheduling problem prevalent in small market-driven foundries is studied. There are two related decision levels: (1) the furnace scheduling of metal alloy production, and (2) moulding machine planning which specifies the type and size of production lots. A mixed integer programming (MIP) formulation of the problem is proposed, but is impractical to solve in reasonable computing time for non-small instances. As a result, a faster relax-and-fix (RF) approach is developed that can also be used on a rolling horizon basis where only immediate-term schedules are implemented. As well as a MIP method to solve the basic RF approach, three variants of a local search method are also developed and tested using instances based on the literature. Finally, foundry-based tests with a real-order book resulted in a very substantial reduction of delivery delays and finished inventory, better use of capacity, and much faster schedule definition compared to the foundry's own practice. |
| |
Keywords: | Lot sizing and scheduling Meta-heuristics Mixed integer programming |
本文献已被 ScienceDirect 等数据库收录! |
|