Publicada By  jpgarcia - complexity theory, Corsari
 This paper addresses a mixed integer linear programming model for operations lot-sizing
and scheduling (assignment and sequencing) in the supply network of a European company which 
assembles customized machine tools through several geographically distributed factories and delivers 
them to the customers’ factory. The results from the model propose a schedule to purchase raw 
material from different suppliers to the various  factories considered, lateral stock transshipments, 
shipments to customers and various operations required for product assembly. Different alternative 
operations (product substitution, alternative procurement and transport operations), considering lead 
times, are contemplated. Specific constraints, such  as space availability in each plant and the two 
backlog types, are considered. A novel approach based on the stroke concept is applied to the MILP 
model to consider alternatives. Since the latest MILP optimizers are not always available, a specific 
procedure to solve the case study based on the graph theory is proposed. Moreover, thanks to this 
concept, the algorithm proposed determines all the feasible solution
21 marzo, 2012