v Description of the tasks involved and how much time is required;
vi Lists of all required replacement parts and their locations;
vii Forecast on the spare parts, tools and their costs;
viii Re-order level of the machine parts and other accessories; and ix
An estimate of the maintenance priorities and their impact.
The most prominent objective of the various techniques in maintenance DSS is to supply vital data and evidence, to derive better strategies to minimize machine
downtime and maintenance cost.
1.5.1 Holonic System
The Holonic concept is based on a theory developed by Koestler 1989. He defined the word holon as a combination of the Greek word holos, which means
whole, and on suggesting a particle or part. The complex adaptive systems will evolve from simple systems much more rapidly if there are stable intermediate forms than if
there are not. Whereas, the resulting complex system in the former case being hierarchical.
Koestler 1989 analysed hierarchy and stable intermediate forms in living organisms and social organizations. Then, he noticed that although it is easy to
identify sub-wholes or parts, wholes and parts in an absolute sense do not exist anywhere. This made Koestler 1989 propose the word holon to describe the hybrid
nature of sub-wholes or parts in real-life systems. Holons are simultaneously self- contained wholes with respect to their subordinated parts, and are dependent parts
when regarded from the inverse direction. The sub-wholes or holons are autonomous, self-reliant units, which have a degree of independence and handle contingencies
without asking higher authorities for instructions.
Simultaneously, holons are subject to control from higher authorities. The first property provided by Christensen 1994 ensures that the holons are stable forms that
can survive disturbances. The latter property signifies that they are intermediate forms, which provide the proper functionality for the bigger whole. Holonic control
architecture can be used in SMI to comply with the concept of hierarchy in distributed systems. In order to have an efficient function in the complex system, every holon has
to behave according to fixed rules and flexible strategies. The fixed rules form a pattern of rules governing behaviour, which lend stability and cohesion between
holons in the group complex system, while flexible strategies allow the holon to be autonomous in a framework of fixed rules. These flexible strategies enable the holon
to determine how it operates and, particularly, how it interacts with other holons in that environment Bongaerts et al., 2000.
In terms of maintenance concerns in SMI, holonic systems can be used to answer questions like “Which machine should be improved and how?”, “What kind
of maintenance strategies are to be used for this machine?”, and “How can this machine be operated more efficiently?”. Then, it is better to simplify the study by
dividing the problems into sub-criteria or parts. After that, a systematic analysis with the DMG model is able to identify the worst production machines and determine
important maintenance strategies. Consequently, the AHP model has to be used to estimate all available alternatives for more efficient decision-making. As a result, by
using the proposed models, maintenance managers have the flexibility to implement the strategies with consideration of other industrial constraints.
1.5.2 Decision-Making Grid
