No abstract

Given the importance of national identity in a country

No abstract

An important issue in maintaining the industrial equipment is to introduce an appropriate maintenance policy to monitor the conditions of the equipment. In this research, an investigation on the concurrent effects of erosion and random shocks during the useful life of the equipment is studied. In this regard a model is introduced to optimize the total cost including logistic, complete repair and incomplete repair costs. The proposed model determines the optimal number of the incomplete repairs, the time duration between inspections and the probability of equipment to be failed. A numerical example is solved by means of computer simulation. The results indicate that the proposed model performs well for minimizing the costs of maintenance and repair.

This article proposes a preventive maintenance policy for equipment that -by their very nature -can cause some forms of contamination and destruction in the environment. The purpose is to reduce overhead costs related to environmental degradation and pollution as well as other costs (e.g., inspection and replacement) by minimizing the function of the average total cost. The condition of equipment should be determined through inspection, and its operating cycle just ends in the event of a failure or precautionary repair. Maintenance services include complete repair or replacement. However, equipment conditions can cause environmental pollution, as the variables for such monitoring go beyond warning limit. After an item has been inspected in unfavorable operating conditions, complete preventive maintenance tasks should be included, in which preparation times and logistics are random variables. A mathematical model and a genetic algorithm are developed to find the optimal inspection strategy for the defined sets of parameters. Moreover, a numerical example is presented and the results are discussed.