Abstract
Level of repair analysis (LORA) is an important method of maintenance decision for establishing system of operation and maintenance in the equipment development period. Currently, the researches of equipment of level of repair focus on economic analysis models which used to optimize costs, rarely consider the maintenance time required by the implementation of maintenance program. In fact, maintenance time is an important factor influencing the availability of equipment system. Considering the relationship between maintenance time and spares stocks level, it is obvious that there are contradictions between maintenance time and cost. In order to balance these two influencing factors, it is necessary to build an optimization LORA model. To this end, maintenance time representing performance characteristic is introduced in this article, and on the basis of spares stocks which is traditionally regarded as decision variable, we add a decision variable of repair level, and build a single-echelon, multi-indenture optimization LORA model which takes the best cost-effectiveness ratio as criterion, expected number of backorder (EBO) as objective function and is subject to a constraint on cost. Besides, the paper designs a convex programming algorithm of multi-variable for the optimization model, provides solution of the non-convex objective function and method of improving the efficiency of the algorithm. It is worth mentioning that the optimization model of level of repair designed in the paper is applicable to the engineering.
