English abstract
Maintenance costs represent a significant and high percentage of the overall operating
and rectification processes in different industries. Applications of Reliability Centred
Maintenance (RCM) and Risk Analysis (RA) are considered key factors that protect the
sustainability of industries. In this study, a concept of RCM has been explored in a
maritime operation, especially in the maintenance of ship in the sultanate of Oman and a
procedure to improve maintenance management plan and policies in such operations are
recommended. For the purpose of the study, at first, two screening phases for marine ship
systems have been commenced by creating fishbone diagrams for the main system and
subsystem on-board ship in parallel with identifying the maintenance significant items
(MSI) by implementing two factors Risk Matrix (RM) analysis.
Subsequently, traditional classic Failure Mode and Effects Analysis (FMEA)
techniques have been utilised for RA by calculating the Risk Priority Number (RPN) for
each item on the system based on the historical data of failures, causes of failure modes
and effects on the three risk factors i.e., severity, occurrence and detectability. Towards
the novelty of the study and to improve traditional FMEA, an Analytic Hierarchy Process
(AHP) is introduced in the traditional FMEA (AHP FMEA) to provide different weights
for the risk factors. Moreover, in the direction of model-based design innovations, a novel
fuzzy logic system is introduced in FMEA (Fuzzy-FMEA), by building fuzzy linguistics
rules applicable to the maritime operation and implementing them in fuzzy toolbox
offered in MATLAB. The model reflects the relationships between risk factors inputs for
the fuzzification of the system items and output of Risk Priority Number (RPN) in the
form of defuzzification of these items. Such a model improves the automation in
maintenance management and effectiveness of FMEA to identify the criticality analysis
of the system and reduce the risk of failure through effective and efficient maintenance
policy towards reliability on the ships system.
Finally, the aforementioned three methods were implemented to a ship Power
Managements System (PMS) to show their applicability and compare the results. The
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results show an improvement in the traditional FMEA with the implementing AHP and
Fuzzy methods. The study also recommended maintenance policy and strategy for each
item of the studied system. The outcome of this study can be used to improve the
reliability of maritime operations in the Sultanate of Oman and move towards the
direction of a value added strategy to enhance the optimal operational mission of the
maritime system.
