Real time oil quality monitoring techniques help to protect important industry assets, minimize downtime and reduce maintenance costs. The measurement of a lubricant's complex permittivity is an effective indicator of the oil degradation process and it can be useful in condition based maintenance (CBM) to select the most adequate oil replacement maintenance schedules. A discussion of the workin...

Novel replacement policies that are hybrids of inspection maintenance and block replacement are developed for an n component series system in which the component parts used at successive replacements arise from a heterogeneous population. The heterogeneous nature of components implies a mixed distribution for time to failure. In these circumstances, a hybrid policy comprising two phases, and ea...

Preventive maintenance is a planned activity to keep the manufacturing facilities in good condition. However, because of limited time and resources, not all the system components can be repaired/replaced during the planned opportunity. When the system is under maintenance, it is very conservative to take the maintenance decision on the components because of limited available time and resources,...

today according to the competitive conditions, companies try to reduce their inventory level to diminish the costs. in companies inventory management and control should establish a balance between inventory level of spare parts, cost and the risk that arising from absence of part when is needed. it is clear that this level of spare parts inventory affected by facility characteristics and its re...

A new replacement analysis methodology is developed to determine system-level component replacement schedules for radial electricity distribution configurations composed of sets of heterogeneous assets. The proposed model is an iterative combined dynamic programming and integer programming approach to obtain cost-efficient system-level component replacement schedules with the objective of minim...

This thesis deals with the reliability and maintenance of structures that are damaged by shocks arriving randomly in time. The degradation is modeled as a cumulative stochastic point process. Previous studies mostly adopted expected cost rate criterion for optimizing the maintenance policies, which ignores practical implications of discounting of maintenance cost over the life cycle of the syst...

This study tries to codify a proper mathematical model which can be predict the costs of repair and maintaining the tractors as precisely as possible for three common models of tractors in Shahid Beheshti cultivation firm in Andimeshk-Ahvaz road of Dezfoul. Studied tractors include: Newhland TM155 Tractor which is chosen from the most perfect file of 10 tractor machines and Jandier tractor-3140...

This study tries to codify a proper mathematical model which can be predict the costs of repair and maintaining the tractors as precisely as possible for three common models of tractors in Shahid Beheshti cultivation firm in Andimeshk-Ahvaz road of Dezfoul. Studied tractors include: Newhland TM155 Tractor which is chosen from the most perfect file of 10 tractor machines and Jandier tractor-3140...

In this paper, an optimal design of the renewable combustion plant has been investigated with the aim of ensuring the required load on the Gorgor station. The purpose of this study is to minimize the cost of the proposed hybrid unit during the period of operation of the designed system simultaneously. Information on the intensity of solar radiation and the intensity of wind blowing in the area ...

Neonatal purpura fulminans is a rare and life threatening disease that can be inherited or acquired in etiology. It manifests as DIC and extensive subcutaneous thrombosis. The condition is often fatal unless there is prompt diagnosis, and judicious therapy. The most important causes of this condition are infections and congenital deficiency of anticoagulant proteins C and S.In the case of PC (p...