In this paper we address the scheduling problem in unpaced synchronous mixe
d-model production lines operated under a cyclic scheduling policy. We firs
t discuss operations of a production line with the synchronous transfer of
parts. We then present an integer programming formulation of the problem. T
he problem, however, is NP-hard, and for its exact solution we propose an i
mplicit enumeration scheme. We discuss a property of the scheduling problem
which allows us to effectively solve large size instances of the problem.
We also present an approximate solution procedure with very good average pe
rformance. Useful managerial insights are obtained as we search for ways to
improve the performance of synchronous lines. The relaxation of one of our
original assumptions in the scheduling problem formulation results in an e
asy problem whose solution generates the absolute best in throughput perfor
mance configuration of the production line. Implementation of this solution
, however, requires increasing the number of buffers in the line. We sugges
t other performance improvement ways to better balance the tradeoff between
throughput and average Work-In-Progress (WIP) inventory in the line.