We consider a maintenance shop that is responsible for the availability of a
eet of assets,
e.g., trains. Unavailability of assets may be due to active maintenance time or unavailability
of spare parts. Both spare assets and spare components may be stocked in order to ensure
a certain percentage of
eet readiness (e.g., 95%), i.e., having sucient assets available for
the primary process (e.g., running a train schedule). This is dierent from guaranteeing a
certain average availability, as is typically done in the literature on spare parts inventories.
We analyse the corresponding system, assuming continuous review and base stock control.
We propose an algorithm, based on a marginal analysis approach, to solve the optimization
problem of minimizing holding costs for spare assets and spare parts. Since the problem is
not item separable, even marginal analysis is time consuming, but we show how to eciently
solve this. Using a numerical experiment, we show that our algorithm generally leads to a
solution that is close to optimal, and we show that our algorithm is much faster than an
existing algorithm for a closely related problem.
|Name||BETA publicatie : working papers|