The authors also gratefully acknowledge the detailed comments of two anonymous referees regarding relationships with lot-sizing problems. ii Abstract This paper studies the polyhedral structure of dynamic fixed-charge problems that have nested relationships constraining the flow or activity variables. Constraints of this type might typically arise in hierarchical or multi-period models, but mig...

Problem statement: Lot-size is the clustering of items for transportation or manufacturing processes occurring at the same time. The issue in lot-size problem is to design production processes so that the feasible production quantities are equal to customer demand quantities and the timing of production is such that inventory positions are almost zero. Approach: In this study, we explore the mu...

The classical multi-level capacitated lot-sizing problem is often not suitable to correctly capture resource requirements and precedence relations. We tackle this issue by explicitly modeling these two aspects. Two models are presented; one considering batch production and the other one allowing lot-streaming. Comparisons with traditional models demonstrate the capability of the new approach to...

Stochastic capacitated lot sizing problem is considered in the presence of probabilistic processing times and demand in this paper. A two-step hierarchical methodology is developed. First, stochastic capacity requirements are determined with statistical analysis & Monte-Carlo simulation. Second, a stochastic nonlinear mixed integer mathematical model is developed to solve the problem.

The wellknown CLSP problem is generalized including sequence dependent setup times and overtimes and modeling it as a quadratic mixed 0-1 integer programming problem called Capacitated Lot Sizing Problem with Sequence Dependent Setups and Overtimes. We develop a heuristics based on Lagrangean relaxation and tabu search for solving the problem. At the end, some computational results are presented.