Decision Sciences Journal
Volume 30, Number 3
Summer 1999
Replanning the Master Production Schedule for a Capacity-Constrained
Job Shop
Kum Khiong Yang
Department of Decision Sciences, Faculty of Business Administration,
National
University of Singapore, Kent Ridge, Singapore 119260, email:
fbaykk@nus.edu.sg
F. Robert Jacobs
Operations and Decision Technology, Kelley School of Business,
Indiana University, Bloomington, IN 47405, email: jacobs@indiana.edu
ABSTRACT. This research examines the use of both frozen
and replanning intervals for planning the master production schedule
(MPS) for a capacity-constrained job shop. The results show that
forecast error, demand lumpiness, setup time, planned lead time,
and order size have a greater impact on the mean total backlog,
total inventory, and number of setups than the frozen and replanning
intervals. The study also shows that a repetitive lot dispatching
rule reduces the importance of lot sizing, and a combination
of repetitive lot dispatching rule and single-period order size
consistently produces the lowest mean total backlog and total
inventory. The results also indicate that rescheduling the open
orders every period produces a lower mean total backlog and total
inventory when the forecast errors are large relative to the
order sizes. This result suggests that the due date of an open
order should be updated only when a significant portion of the
order is actually needed on the new due date.
Subject Areas: Job Shop Scheduling, Master Production
Scheduling, Repetitive Manufacturing, and Simulation. |