Ph. Liu, A comparative study of three tool replacement/operation sequencing strategies in a flexible manufacturing system, NAV RES LOG, 47(6), 2000, pp. 479-499
This paper studies three tool replacement/operation sequencing strategies f
or a flexible manufacturing system over a finite time horizon: (1) failure
replacement-replace the tool only upon failure, (2) optimal preventive tool
replacement for a fixed sequence of operations, and (3) joint scheduling o
f the optimal preventive tool replacement times and the optimal sequence of
operations. Stochastic dynamic decision models are used for strategies 2 a
nd 3. The optimization criterion for strategies 2 and 3 is the minimization
of the total expected cost over the finite time horizon, We will show thro
ugh numerical studies that, with the same amount of information, the total
expected costs can be reduced considerably by choosing an optimal strategy.
Our conclusion is that in flexible manufacturing, optimal tool replacement
and optimal operations sequencing are not separate issues. They should be
considered jointly to minimize the expected total cost. (C) 2000 John Wiley
& Sons, Inc.