Details

Autor(en) / Beteiligte

• Zhang, Minjiao
• Küçükyavuz, Simge
• Yaman, Hande

Titel

A Polyhedral Study of Multiechelon Lot Sizing with Intermediate Demands

Ist Teil von

• Operations research, 2012-07, Vol.60 (4), p.918-935

Ort / Verlag

Hanover, MD: INFORMS

Erscheinungsjahr

2012

Quelle

BSC - Ebsco (Business Source Ultimate)

Beschreibungen/Notizen

• In this paper, we study a multiechelon uncapacitated lot-sizing problem in series ( m -ULS), where the output of the intermediate echelons has its own external demand and is also an input to the next echelon. We propose a polynomial-time dynamic programming algorithm, which gives a tight, compact extended formulation for the two-echelon case (2-ULS). Next, we present a family of valid inequalities for m -ULS, show its strength, and give a polynomial-time separation algorithm. We establish a hierarchy between the alternative formulations for 2-ULS. In particular, we show that our valid inequalities can be obtained from the projection of the multicommodity formulation. Our computational results show that this extended formulation is very effective in solving our uncapacitated multi-item two-echelon test problems. In addition, for capacitated multi-item, multiechelon problems, we demonstrate the effectiveness of a branch-and-cut algorithm using the proposed inequalities.